A comparison of the boomerang wire vascular access management system versus manual compression alone during percutaneous diagnostic and interventional cardiovascular procedures.

PubMed

Echeverria, Angela; Krajcer, Zvonimir

2016-01-01

Vascular closure devices allow for early sheath removal, allowing for earlier patient mobilization The Boomerang vascular access management system does not alter arterial integrity for future interventions Access site complications provide significant morbidity in diagnostic and therapeutic interventions. © 2016 Wiley Periodicals, Inc.

Evaluation of ultrasound-guided vascular access in dogs.

PubMed

Chamberlin, Scott C; Sullivan, Lauren A; Morley, Paul S; Boscan, Pedro

2013-01-01

To describe the technique and determine the feasibility, success rate, perceived difficulty, and time to vascular access using ultrasound guidance for jugular vein catheterization in a cardiac arrest dog model. Prospective descriptive study. University teaching hospital. Nine Walker hounds. A total of 27 jugular catheterizations were performed postcardiac arrest using ultrasound guidance. Catheterizations were recorded based on the order in which they were performed and presence/absence of a hematoma around the vein. Time (minutes) until successful vascular access and perceived difficulty in achieving vascular access (scale of 1 = easy to 10 = difficult) were recorded for each catheterization. Mean time to vascular access was 1.9 minutes (95% confidence interval, 1.1-3.4 min) for catheterizations without hematoma, versus 4.3 minutes (1.8-10.1 min) for catheterizations with hematoma (P = 0.1). Median perceived difficulty was 2 of 10 (range 1-7) for catheterizations without hematoma, versus 2 of 10 (range 1-8) for catheterizations with hematoma (P = 0.3). A learning curve was evaluated by comparing mean time to vascular access and perceived difficulty in initial versus subsequent catheterizations. Mean time to vascular access was 2.5 minutes (1.0-6.4 min) in the initial 13 catheterizations versus 3.3 minutes (1.5-7.5 min) in the subsequent 14 catheterizations (P = 0.6). Median perceived difficulty in the first 13 catheterizations (3, range 1-8) was significantly greater (P = 0.049) than median perceived difficulty in the subsequent 14 catheterizations (2, range 1-6). Ultrasound-guided jugular catheterization is associated with a learning curve but is successful in obtaining rapid vascular access in dogs. Further prospective studies are warranted to confirm the utility of this technique in a clinical setting. © Veterinary Emergency and Critical Care Society 2013.

Value of doppler ultrasonography in the study of hemodialysis peripheral vascular access dysfunction.

PubMed

Moreno Sánchez, T; Martín Hervás, C; Sola Martínez, E; Moreno Rodríguez, F

2014-01-01

The main objectives of this study were to evaluate the sensitivity and specificity of duplex Doppler ultrasonography in the study of hemodialysis peripheral vascular access dysfunction and to analyze the resistance index and flow in the afferent artery. We prospectively studied 178 patients with 178 peripheral vascular accesses that were dysfunctional in at least three consecutive hemodialysis sessions. Patients underwent duplex Doppler ultrasonography and clinical and laboratory follow-up for three months (provided angiography findings were negative). We calculated the sensitivity, specificity, predictive values, and coefficients of probability. We studied the morphology of the afferent artery, the arteriovenous anastomosis, and the efferent vein, and we measured the resistance index and the flow of the afferent artery, the diameter of the anastomosis, and the flow and peak systolic velocity in the efferent vein. The final sample consisted of 159 patients. The sensitivity, specificity, positive and negative predictive values, and positive and negative coefficients of probability were 0,98 (95% CI: 0,88-1.00), 0,74 (95% CI: 0,66-0,81), 0,96, 0,82, 3.7, and 0,03, respectively. The resistance index was less than 0,5 in 78.5% of the peripheral vascular accesses with normal function and greater than 0,5 in 86.1% of the dysfunctional peripheral vascular accesses. We found aneurysms in 19 of the native peripheral vascular accesses and pseudoaneurysms in 7 of the prosthetic grafts. Inverted flow was seen in 57 peripheral vascular accesses. Duplex Doppler ultrasonography is an efficacious method for detecting and characterizing stenosis and thrombosis in peripheral vascular accesses, and it provides information about the morphology and hemodynamics. Copyright © 2012 SERAM. Published by Elsevier Espana. All rights reserved.

Association between vascular access failure and microparticles in hemodialysis patients

PubMed Central

Ryu, Jung-Hwa; Lim, Su-Young; Ryu, Dong-Ryeol; Kang, Duk-Hee; Choi, Kyu Bok; Kim, Seung-Jung

2012-01-01

Background Vascular access failure, a major cause of morbidity in hemodialysis (HD) patients, occurs mainly at stenotic endothelium following an acute thrombotic event. Microparticles (MPs) are fragments derived from injured cell membrane and are closely associated with coagulation and vascular inflammatory responses. Methods We investigated the relationship between levels of circulating MPs and vascular access patency in HD patients. A total of 82 HD patients and 28 healthy patients were enrolled. We used flow cytometry to measure endothelial MPs (EMPs) identified by CD31+CD42− or CD51+ and platelet-derived MPs (PMPs) identified by CD31+CD42+ in plasma samples of participants. Vascular access patency was defined as an interval from the time of access formation to the time of first access stenosis in each patient. MP counts were compared according to access patent duration. Results The levels of EMP (both CD31+CD42− and CD51+) and CD31+CD42+PMP were significantly higher in patients than in healthy participants. Levels of CD31+CD42−EMP and CD31+CD42+PMP showed a positive correlation. In non-diabetic HD patients, CD31+CD42−EMPs and CD31+CD42+PMPs were more elevated in the shorter access survival group (access survival <1 year) than in the longer survival group (access survival ≥ 4 years). Conclusion Elevated circulating EMP or PMP counts are influenced by end-stage renal disease and increased levels of EMP and PMP may be associated with vascular access failure in HD patients. PMID:26889407

Disruptive technological advances in vascular access for dialysis: an overview.

PubMed

Yeo, Wee-Song; Ng, Qin Xiang

2017-11-29

End-stage kidney disease (ESKD), one of the most prevalent diseases in the world and with increasing incidence, is associated with significant morbidity and mortality. Current available modes of renal replacement therapy (RRT) include dialysis and renal transplantation. Though renal transplantation is the preferred and ideal mode of RRT, this modality may not be available to all patients with ESKD. Moreover, renal transplant recipients are constantly at risk of complications associated with immunosuppression and immunosuppressant use, and posttransplant lymphoproliferative disorder. Dialysis may be the only available modality in certain patients. However, dialysis has its limitations, which include issues associated with lack of vascular access, risks of infections and vascular thrombosis, decreased quality of life, and absence of biosynthetic functions of the kidney. In particular, the creation and maintenance of hemodialysis vascular access in children poses a unique set of challenges to the pediatric nephrologist owing to the smaller vessel diameters and vascular hyperreactivity compared with adult patients. Vascular access issues continue to be one of the major limiting factors prohibiting the delivery of adequate dialysis in ESKD patients and is the Achilles' heel of hemodialysis. This review aims to provide a critical overview of disruptive technological advances and innovations for vascular access. Novel strategies in preventing neointimal hyperplasia, novel bioengineered products, grafts and devices for vascular access will be discussed. The potential impact of these solutions on improving the morbidity encountered by dialysis patients will also be examined.

Right line, right patient, right time: every choice matters.

PubMed

Jackson, Tim; Hallam, Carole; Corner, Tracey; Hill, Steve

The field of vascular access has developed significantly over recent decades. It has been adapted to provide a range of techniques for a range of patients much faster than a full appreciation of the risks involved has developed. Improved governance of vascular access procedures in the UK is needed. This is driven by a deeper understanding of risks such as infectious and thrombotic complications, repeated failures of peripheral intravenous (IV) access leading to poor patient experience and treatment inadequacy, and the increasing emphasis on avoiding healthcare-associated infections. The Vessel Health and Preservation (VHP) protocol, which is used to standardise vascular access practice in the US is being evaluated for adoption in the UK. A comprehensive and inclusive approach should be taken to the vascular access needs of all patients.

Blood Flow in Idealized Vascular Access for Hemodialysis: A Review of Computational Studies.

PubMed

Ene-Iordache, Bogdan; Remuzzi, Andrea

2017-09-01

Although our understanding of the failure mechanism of vascular access for hemodialysis has increased substantially, this knowledge has not translated into successful therapies. Despite advances in technology, it is recognized that vascular access is difficult to maintain, due to complications such as intimal hyperplasia. Computational studies have been used to estimate hemodynamic changes induced by vascular access creation. Due to the heterogeneity of patient-specific geometries, and difficulties with obtaining reliable models of access vessels, idealized models were often employed. In this review we analyze the knowledge gained with the use of computational such simplified models. A review of the literature was conducted, considering studies employing a computational fluid dynamics approach to gain insights into the flow field phenotype that develops in idealized models of vascular access. Several important discoveries have originated from idealized model studies, including the detrimental role of disturbed flow and turbulent flow, and the beneficial role of spiral flow in intimal hyperplasia. The general flow phenotype was consistent among studies, but findings were not treated homogeneously since they paralleled achievements in cardiovascular biomechanics which spanned over the last two decades. Computational studies in idealized models are important for studying local blood flow features and evaluating new concepts that may improve the patency of vascular access for hemodialysis. For future studies we strongly recommend numerical modelling targeted at accurately characterizing turbulent flows and multidirectional wall shear disturbances.

Peripheral arteriovenous fistula as vascular access for long-term chemotherapy.

PubMed

Kovalyov, Oleksiy O; Kostyuk, Oleksandr G; Tkachuk, Tetyana V

To provide long-term vascular access in clinical oncology peripheral forearm veins (up to 95% of patients in Ukraine), central venous access and "complete implanted vascular systems" are used most often. Many oncology patients have contraindications to catheterization of superior vena cava. Besides, exploitation of central veins is associated with potential technical and infectious complications. The aim - to study short-term and long-term results of arteriovenous fistula exploitation as vascular access for continuous anticancer therapy. Peripheral venous bed status in 41 oncology patients taking long-term chemotherapy treatment is analyzed in the article. Doppler sonography, morphologic and immune histochemical analyses were used in the study. Doppler sonography found qualitative and quantitative changes in forearm veins at different time periods after initiation of chemotherapy in the majority of patients. The major morphologic manifestations of venous wall damage were chemical phlebitis, local or extended hardening of venous wall, venous thrombosis and extravasations with necrosis and subsequent paravasal tissue sclerosis. Alternative vascular access created in 12 patients completely met the adequacy criteria (safety, multiple use, longevity, realization of the designed therapy program). The conclusion was made about inapplicability of forearm veins for long-term administration of cytostatic agents. If it is impossible to use central veins, arteriovenous fistula can become an alternative vascular access.

Vascular access type, health-related quality of life, and depression in hemodialysis patients: a preliminary report.

PubMed

Afsar, Baris; Elsurer, Rengin; Covic, Adrian; Kanbay, Mehmet

2012-01-01

Arteriovenous fistulas (AVF) are the vascular access of choice for hemodialysis (HD) compared with arteriovenous grafts (AVG) and central venous catheters (CVC). In spite of increasing recognition of importance of a patient's perception of health-related quality of life (HRQOL) and depression, few studies have assessed the association of vascular access type with HRQOL and depression. The purpose of our study was to examine HRQOL and depression among patients with different vascular access. Severity of symptoms of depression and HRQOL were assessed by Beck Depression Inventory (BDI) and Short Form-36 (SF-36), respectively. Vascular access was reported as one of three options; AVF, AVG, and CVC. In total, 136 patients were included; 104 had AVF, 15 had AVG, and 17 had CVC. BDI and HRQOL parameters differed among patients with different vascular access types. In post hoc analysis, BDI and HRQOL subscales were not different between patients with AVF and AVG. Patients with CVC had lower physical functioning (P:.001), role-physical limitation (P:.015), general health perception (P:.017), vitality (P:.010), social functioning (P:.004), role-emotional (P:.008), mental health (P:.001), physical component summary score (P:.017), and mental component summary score (P:.006) when compared to patients with AVF. Patients with CVC had lower physical functioning (P:.044), role-emotional (P:.044) and mental health scores (P:.04) when compared to patients with AVG. Having a CVC may negatively influence HRQOL in HD patients. Vascular access type does not seem to be related to depressed mood in HD.

The Use of the 'Preclosure' Technique for Antegrade Aspiration Thrombectomy with Large Catheters in Acute Limb Ischemia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Funke, C., E-mail: claas_funke@hotmail.com; Pfiffner, R.; Husmann, M.

2013-04-15

This study was designed to assess retrospectively short- and mid-term outcomes of the use of a suture-mediated closure device to close the antegrade access in patients undergoing percutaneous aspiration thrombectomy with large catheters for acute leg ischemia. Between November 2005 and February 2010, a suture-mediated active closure system (ProGlide{sup Registered-Sign} 6F, Abbott) was placed before arterial sheath (mean 9 F, range 6-12 F) introduction in 101 patients (74 men, 73 %, mean age 70.1 {+-} 12.6 years standard deviation). Data regarding mortality, complications, and factors contributing to vascular complications at the access site was collected for 6 month after themore » intervention to detect device-related problems. As a coincidence, 77 patients had follow-up visits for a duplex ultrasound. There were a total of 19 vascular complications (19 %) at the puncture site, all of which were of hemorrhagic nature and none of which consisted of vessel occlusion. Two major outcome complications (2 %) occurred. A retroperitoneal hematoma and a serious inguinal bleeding required additive treatment and did not result in permanent sequelae. Nine cases involved death of which eight were not attributable to the closure and one remained unclear. Successful closure was achieved in 95 patients (94 %); additional manual compression was sufficient in the majority of the remaining patients. Numerous factors contributing to vascular complications were encountered. With acceptable short- and mid-term outcomes, the 'preclose' technique can be a reliable option for the closure of a large antegrade femoral access even for patients at a high risk of vascular complications, such as those undergoing aspiration thrombectomy.« less

Feasibility of Human Skin Grafts on an Isolated But Accessible Vascular Supply on Athymic Rats as a System to Study Percutaneous Penetration and Cutaneous Injury.

DTIC Science & Technology

1986-04-01

Ai87 466 FEASIBILITY OF HUMAN SKIN GRAFTS ON AN ISOLATED BUT / ACCESSIBLE VASCULAR 5 (U) UTAH UNIV SALT LAKE CITY SCHOOL OF MEDICINE 6 G KRUEGER APR...GOVT ACCESSION NO . RrCIPIcNTrS CATALOG NUMIER Feasibility of Human Skin Grafts on an Isolated 9 but Accessible Vascular Supply on Athymic Rats as...of the Skin Sandwich Flap....... . . . . . . . 35 Figure 15. Photograph of Hair Growth in a Human Split-Thickness Skin Graft on a Nude Rat

Features and selection of vascular access devices.

PubMed

Sansivero, Gail Egan

2010-05-01

To review venous anatomy and physiology, discuss assessment parameters before vascular access device (VAD) placement, and review VAD options. Journal articles, personal experience. A number of VAD options are available in clinical practice. Access planning should include comprehensive assessment, with attention to patient participation in the planning and selection process. Careful consideration should be given to long-term access needs and preservation of access sites. Oncology nurses are uniquely suited to perform a key role in VAD planning and placement. With knowledge of infusion therapy, anatomy and physiology, device options, and community resources, nurses can be key leaders in preserving vascular access and improving the safety and comfort of infusion therapy. Copyright 2010 Elsevier Inc. All rights reserved.

Vascular access in lipoprotein apheresis: a retrospective analysis from the UK's largest lipoprotein apheresis centre.

PubMed

Doherty, Daniel J; Pottle, Alison; Malietzis, George; Hakim, Nadey; Barbir, Mahmoud; Crane, Jeremy S

2018-01-01

Lipoprotein apheresis (LA) has proven to be an effective, safe and life-saving therapy. Vascular access is needed to facilitate this treatment but has recognised complications. Despite consistency in treatment indication and duration there are no guidelines in place. The aim of this study is to characterise vascular access practice at the UK's largest LA centre and forward suggestions for future approaches. A retrospective analysis of vascular access strategies was undertaken in all patients who received LA treatment in the low-density lipoprotein (LDL) Apheresis Unit at Harefield Hospital (Middlesex, UK) from November 2000 to March 2016. Fifty-three former and current patients underwent 4260 LA treatments. Peripheral vein cannulation represented 79% of initial vascular access strategies with arteriovenous (AV) fistula use accounting for 15%. Last used method of vascular access was peripheral vein cannulation in 57% versus AV fistula in 32%. Total AV fistula failure rate was 37%. Peripheral vein cannulation remains the most common method to facilitate LA. Practice trends indicate a move towards AV fistula creation; the favoured approach receiving support from the expert body in this area. AV fistula failure rate is high and of great concern, therefore we suggest the implementation of upper limb ultrasound vascular mapping in all patients who meet treatment eligibility criteria. We encourage close ties between apheresis units and specialist surgical centres to facilitate patient counselling and monitoring. Further prospective data regarding fistula failure is needed in this expanding treatment field.

Common Femoral Artery Access on YouTube: What Practices are Being Shown and Who is Delivering the Message?

PubMed

Pitcher, Grayson S; Newton, Daniel H; Amendola, Michael F

Novice learners are increasingly turning to YouTube as a learning resource for surgical procedures. One example of such a procedure is common femoral artery puncture and sheath placement. Practitioners in several specialties perform this procedure to access the arterial system for angiography and intervention. We set forth to compare the techniques demonstrated on YouTube by the various specialists, as well as compare each specialty׳s prevalence on this website. YouTube (www.youtube.com) was accessed in December 2015 at multiple time points with a cleared-cache web browser for the keyword search categories: "femoral artery access," "femoral access," and "angiography access." The top 500 videos from each of these keyword searches were analyzed. Videos were categorized by practitioner specialty, technique, duration of video, age of video, and total views. Videos with clear demonstration of femoral artery access were included in the analysis. All industry videos were excluded from the analysis. Categorical variables were compared using Fisher׳s exact test, and continuous variables were compared with the Student׳s t-test. A total of 2460, 4680 and 1800 videos were found for each keyword search, respectively. Of these, 33 videos clearly demonstrated femoral artery access technique. Vascular specialists, compared to interventional cardiology and radiology, had fewer videos (n = 4 vs. 14) and older videos (3.5 ± 2.1y vs. 2.25 ± 0.5y, p < 0.05). The vascular specialists demonstrated ultrasound-guided access, while interventional cardiology predominantly demonstrated landmark-guided access (p < 0.05). Although YouTube and other online resources are being used by novice learners, vascular specialists are underrepresented for femoral artery access, a foundational vascular procedure. Other practitioners demonstrate videos with landmark-guided access and rarely demonstrate ultrasound use. As recognized vascular experts, vascular surgeons should improve their visibility in online learning resources. Copyright © 2017 Association of Program Directors in Surgery. All rights reserved.

Outcomes of Elderly Patients after Predialysis Vascular Access Creation

PubMed Central

Lee, Timmy; Thamer, Mae; Zhang, Yi; Zhang, Qian

2015-01-01

Uniform vascular access guidelines for elderly patients may be inappropriate because of the competing risk of death, high rate of arteriovenous fistula (AVF) maturation failure, and poor vascular access outcomes in this population. However, the outcomes in elderly patients with advanced CKD who receive permanent vascular access before dialysis initiation are unclear. We identified a large nationally representative cohort of 3418 elderly patients (aged ≥70 years) with CKD undergoing predialysis AVF or arteriovenous graft (AVG) creation from 2004 to 2009, and assessed the frequencies of dialysis initiation, death before dialysis initiation, and dialysis-free survival for 2 years after vascular access creation. In all, 67% of patients with predialysis AVF and 71% of patients with predialysis AVG creation initiated dialysis within 2 years of access placement, but the overall risk of dialysis initiation was modified by patient age and race. Only one half of patients initiated dialysis with a functioning AVF or AVG; 46.8% of AVFs were created <90 days before dialysis initiation. Catheter dependence at dialysis initiation was more common in patients receiving predialysis AVF than in patients receiving AVG (46.0% versus 28.5%; P<0.001). In conclusion, most elderly patients with advanced CKD who received predialysis vascular access creation initiated dialysis within 2 years. As a consequence of late predialysis placement or maturation failure, almost one half of patients receiving AVFs initiated dialysis with a catheter. Insertion of an AVG closer to dialysis initiation may serve as a “catheter-sparing” approach and allow delay of permanent access placement in selected elderly patients with CKD. PMID:25855782

Outcomes of Elderly Patients after Predialysis Vascular Access Creation.

PubMed

Lee, Timmy; Thamer, Mae; Zhang, Yi; Zhang, Qian; Allon, Michael

2015-12-01

Uniform vascular access guidelines for elderly patients may be inappropriate because of the competing risk of death, high rate of arteriovenous fistula (AVF) maturation failure, and poor vascular access outcomes in this population. However, the outcomes in elderly patients with advanced CKD who receive permanent vascular access before dialysis initiation are unclear. We identified a large nationally representative cohort of 3418 elderly patients (aged ≥ 70 years) with CKD undergoing predialysis AVF or arteriovenous graft (AVG) creation from 2004 to 2009, and assessed the frequencies of dialysis initiation, death before dialysis initiation, and dialysis-free survival for 2 years after vascular access creation. In all, 67% of patients with predialysis AVF and 71% of patients with predialysis AVG creation initiated dialysis within 2 years of access placement, but the overall risk of dialysis initiation was modified by patient age and race. Only one half of patients initiated dialysis with a functioning AVF or AVG; 46.8% of AVFs were created <90 days before dialysis initiation. Catheter dependence at dialysis initiation was more common in patients receiving predialysis AVF than in patients receiving AVG (46.0% versus 28.5%; P<0.001). In conclusion, most elderly patients with advanced CKD who received predialysis vascular access creation initiated dialysis within 2 years. As a consequence of late predialysis placement or maturation failure, almost one half of patients receiving AVFs initiated dialysis with a catheter. Insertion of an AVG closer to dialysis initiation may serve as a "catheter-sparing" approach and allow delay of permanent access placement in selected elderly patients with CKD. Copyright © 2015 by the American Society of Nephrology.

[Thrombosis in vascular accesses for haemodialysis: rescue treatment using invasive vascular radiological techniques].

PubMed

García Medina, J; Lacasa Pérez, N; Muray Cases, S; Pérez Garrido, I; García Medina, V

2009-01-01

The purpose of this paper is to communicate our experience in the salvage of thrombosed haemodialysis vascular accesses using interventional radiology techniques. In the last four years, we have treated, by radiological means, 101 thrombosed haemodialysis vascular accesses. There were 44 autologous arteriovenous fistulas (43.56%) and 57 PTFE grafts (56.44%). There were 69 men (68.3%) and 32 women (31.7%). The mean age was 67.73 years (range 33-84). The mean vascular access age was 23.79 months (range 1-132). Manual catheter-directed aspiration was used. Fragmented, triturated or pushed the thrombus against the pulmonary circulation was avoided in all cases. 78 accesses were salvaged (77.2%). Autologous fistulas average and PTFE grafts success rate were 84.44% and 71.42% respectively. Angioplasty in one or more lesions after thromboaspiration was performed in all accesses, except six (5.9%). Metallic endoprostheses were implanted in 14 accesses (13.9%). Mean follow-up was 9 months (range 0-44). Primary patency was 42.3% +/- 5 at 6 months and 32% +/- 4 at one year. Autologous fistulas patency was better than PTFE grafts patency (p < or =0,05). Our results suggest thrombosed autologous arteriovenous fistulas salvage is better than PTFE grafts. This justifies interventional radiology techniques in these situations.

Spanish Clinical Guidelines on Vascular Access for Haemodialysis.

PubMed

Ibeas, José; Roca-Tey, Ramon; Vallespín, Joaquín; Moreno, Teresa; Moñux, Guillermo; Martí-Monrós, Anna; Del Pozo, José Luis; Gruss, Enrique; Ramírez de Arellano, Manel; Fontseré, Néstor; Arenas, María Dolores; Merino, José Luis; García-Revillo, José; Caro, Pilar; López-Espada, Cristina; Giménez-Gaibar, Antonio; Fernández-Lucas, Milagros; Valdés, Pablo; Fernández-Quesada, Fidel; de la Fuente, Natalia; Hernán, David; Arribas, Patricia; Sánchez de la Nieta, María Dolores; Martínez, María Teresa; Barba, Ángel

2017-11-01

Vascular access for haemodialysis is key in renal patients both due to its associated morbidity and mortality and due to its impact on quality of life. The process, from the creation and maintenance of vascular access to the treatment of its complications, represents a challenge when it comes to decision-making, due to the complexity of the existing disease and the diversity of the specialities involved. With a view to finding a common approach, the Spanish Multidisciplinary Group on Vascular Access (GEMAV), which includes experts from the five scientific societies involved (nephrology [S.E.N.], vascular surgery [SEACV], vascular and interventional radiology [SERAM-SERVEI], infectious diseases [SEIMC] and nephrology nursing [SEDEN]), along with the methodological support of the Cochrane Center, has updated the Guidelines on Vascular Access for Haemodialysis, published in 2005. These guidelines maintain a similar structure, in that they review the evidence without compromising the educational aspects. However, on one hand, they provide an update to methodology development following the guidelines of the GRADE system in order to translate this systematic review of evidence into recommendations that facilitate decision-making in routine clinical practice, and, on the other hand, the guidelines establish quality indicators which make it possible to monitor the quality of healthcare. Copyright © 2017 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

Patients with chronic kidney disease: safety aspects in the preoperative management.

PubMed

Malovrh, Marko

2015-01-01

Chronic kidney disease (CKD) is a major public health problem worldwide. Early detection and treatment of CKD can often prevent or delay some of the negative outcomes of CKD. This chapter shows how treatment of hypertension, proteinuria and metabolic disorders slow down the deterioration of renal function. Irrespective of the mode of renal replacement therapy, maintaining the veins in the upper extremities is of vital importance. Below are suggestions on how to protect blood vessels of the upper limbs and when to start preparing for the construction of vascular access. In this chapter, it is also shown how necessary it is to conduct a clinical evaluation of the blood vessels, which is required before the start of vascular access management. The methodology of noninvasive evaluation of vessels by duplex sonography is also presented. This method is very useful, especially if the vessels are not clinically visible, as well as the information concerning the morphological and functional properties of blood vessels. © 2015 S. Karger AG, Basel

Airway management and vascular access simulation during a medical student rotation.

PubMed

Sakawi, Yasser; Vetter, Thomas R

2011-03-01

Medical students electing to spend a month in anaesthesiology during their third or fourth year often experience airway management and vascular access for the first time on an actual patient. An airway management and vascular access simulation course for medical students was developed and implemented at our institution. The purpose of this study was to assess the subjective comfort level after implementing this teaching tool in medical students. A brief didactic course on airway management and vascular access was provided to medical students on the first day of their anaesthesiology rotation. A survey was presented to the students immediately after a focused 1-hour lecture and prior to a simulation session. The pre-simulation survey was comprised of eight questions asking the medical students to rate their level of comfort with both types of procedures. The lecture was followed by a 1-hour simulation course on manikins. The medical students were asked to complete a post-simulation survey, which was comprised of the same initial eight questions. After participating in the didactic course and manikin simulation, the self-perceived comfort level of medical students with airway management (p < 0.0005), vascular access (p < 0.0005) and interpretation of the vascular pressure waveforms (p < 0.0005) demonstrated significant improvement. The results of this study suggest that providing medical students with a brief didactic session on airway and vascular access, including simulation on manikins, prior to the start of their encounter with actual surgical patients, can improve their comfort level in performing both procedures. © Blackwell Publishing Ltd 2011.

Emergency intraosseous access in a helicopter emergency medical service: a retrospective study.

PubMed

Sunde, Geir A; Heradstveit, Bård E; Vikenes, Bjarne H; Heltne, Jon K

2010-10-07

Intraosseous access (IO) is a method for providing vascular access in out-of-hospital resuscitation of critically ill and injured patients when traditional intravenous access is difficult or impossible. Different intraosseous techniques have been used by our Helicopter Emergency Medical Services (HEMS) since 2003. Few articles document IO use by HEMS physicians. The aim of this study was to evaluate the use of intraosseous access in pre-hospital emergency situations handled by our HEMS. We reviewed all medical records from the period May 2003 to April 2010, and compared three different techniques: Bone Injection Gun (B.I.G® - Waismed), manual bone marrow aspiration needle (Inter V - Medical Device Technologies) and EZ-IO® (Vidacare), used on both adults and paediatric patients. During this seven-year period, 78 insertion attempts were made on 70 patients. Overall success rates were 50% using the manual needle, 55% using the Bone Injection Gun, and 96% using the EZ-IO®. Rates of success on first attempt were significantly higher using the EZ-IO® compared to the manual needle/Bone Injection Gun (p < 0.01/p < 0.001). Fifteen failures were due to insertion-related problems (19.2%), with four technical problems (5.1%) and three extravasations (3.8%) being the most frequent causes. Intraosseous access was primarily used in connection with 53 patients in cardiac arrest (75.7%), including traumatic arrest, drowning and SIDS. Other diagnoses were seven patients with multi-trauma (10.0%), five with seizures/epilepsy (7.1%), three with respiratory failure (4.3%) and two others (2.9%). Nearly one third of all insertions (n = 22) were made in patients younger than two years. No cases of osteomyelitis or other serious complications were documented on the follow-up. Newer intraosseous techniques may enable faster and more reliable vascular access, and this can lower the threshold for intraosseous access on both adult and paediatric patients in critical situations. We believe that all emergency services that handle critically ill or injured paediatric and adult patients should be familiar with intraosseous techniques.

Emergency intraosseous access in a helicopter emergency medical service: a retrospective study

PubMed Central

2010-01-01

Background Intraosseous access (IO) is a method for providing vascular access in out-of-hospital resuscitation of critically ill and injured patients when traditional intravenous access is difficult or impossible. Different intraosseous techniques have been used by our Helicopter Emergency Medical Services (HEMS) since 2003. Few articles document IO use by HEMS physicians. The aim of this study was to evaluate the use of intraosseous access in pre-hospital emergency situations handled by our HEMS. Methods We reviewed all medical records from the period May 2003 to April 2010, and compared three different techniques: Bone Injection Gun (B.I.G® - Waismed), manual bone marrow aspiration needle (Inter V - Medical Device Technologies) and EZ-IO® (Vidacare), used on both adults and paediatric patients. Results During this seven-year period, 78 insertion attempts were made on 70 patients. Overall success rates were 50% using the manual needle, 55% using the Bone Injection Gun, and 96% using the EZ-IO®. Rates of success on first attempt were significantly higher using the EZ-IO® compared to the manual needle/Bone Injection Gun (p < 0.01/p < 0.001). Fifteen failures were due to insertion-related problems (19.2%), with four technical problems (5.1%) and three extravasations (3.8%) being the most frequent causes. Intraosseous access was primarily used in connection with 53 patients in cardiac arrest (75.7%), including traumatic arrest, drowning and SIDS. Other diagnoses were seven patients with multi-trauma (10.0%), five with seizures/epilepsy (7.1%), three with respiratory failure (4.3%) and two others (2.9%). Nearly one third of all insertions (n = 22) were made in patients younger than two years. No cases of osteomyelitis or other serious complications were documented on the follow-up. Conclusions Newer intraosseous techniques may enable faster and more reliable vascular access, and this can lower the threshold for intraosseous access on both adult and paediatric patients in critical situations. We believe that all emergency services that handle critically ill or injured paediatric and adult patients should be familiar with intraosseous techniques. PMID:20929544

Prophylactic antibiotic therapy prior to dental treatment for patients with end-stage renal disease.

PubMed

Werner, C W; Saad, T F

1999-01-01

In the United States, there is a large and growing population of patients undergoing dialysis because of end-stage renal disease (ESRD). These patients present special management considerations for dentists, including antibiotic prophylaxis for the prevention of bacterial endocarditis (BE). ESRD patients, particularly those with an arteriovenous shunt for hemodialysis access, are predisposed to valvular endocarditis. Thus, BE prevention is the primary goal of antibiotic prophylaxis prior to dental or other invasive procedures in these patients. Bacteremia may predispose to infection of synthetic vascular access grafts, although this form of endovascular infection in ESRD patients has not been as well-characterized as BE. Antibiotic prophylaxis may be of some benefit for prevention of synthetic graft infections as well as BE. Poor dentist and physician compliance with BE prophylaxis regimens, as well as errors in dosing, timing, or duration of prophylaxis, have been reported. These problems are of particular concern in the treatment of chronically ill patients. In this article, we review the rationale for prophylactic antibiotic therapy prior to dental procedures in ESRD patients with vascular access. We also elaborate on the current American Heart Association guidelines for BE prophylaxis, and address special considerations for ESRD patients.

Long-term central venous access device selection.

PubMed

Gabriel, Janice

Infusion therapy is often viewed as a means to an end - a way to administer medications and fluids. It is one of the few specialties that affect almost all areas of healthcare. Safe, effective and reliable vascular access should be the goal of every health professional who is starting a patient on a prescribed course of intravenous therapy, especially if that patient is undergoing a prolonged course. This article aims to refresh and update nurses' clinical knowledge of the detailed patient assessment required before choosing a central venous access device, as well as supporting a reduction in complications and earlier recognition of potential problems. It discusses clinical indications for devices, the range of long-term intravenous therapies that can be used, and patient assessment.

Reinforced aneurysmorrhaphy for true aneurysmal haemodialysis vascular access.

PubMed

Rokošný, S; Baláž, P; Wohlfahrt, P; Palouš, D; Janoušek, L

2014-04-01

In 2008, a new technique of reinforced aneurysmorrhaphy with a polyester mesh tube for salvaging true aneurysmal arteriovenous (AV) haemodialysis access was described by us. In this study, the long-term patency and complication rates associated with this procedure were analysed, and the effect of reinforced aneurysmorrhaphy on high-flow vascular access was assessed. This was a retrospective non-randomised study with prospectively collected data performed at a single centre. Patients with true aneurysmal haemodialysis AV access who underwent aneurysmorrhaphy with external mesh prosthesis between March 2007 and October 2012 were included. Clinical assessment and duplex ultrasound were performed preoperatively, 1, 3, and 12 months postoperatively, and annually thereafter. Data from 62 patients (median age 60 years, range 28-81 years; 63% men) were analysed. The commonest indication was high-flow vascular access associated with the risk of high output cardiac failure (24 patients, 39%). The mean follow-up time was 14.66 ± 12.80 months. Primary patency rates at 6 and 12 months were 86% and 79% respectively. Assisted primary patency rates at 6 and 12 months were 89% and 80% respectively. In 23 patients (96%) operated on for high-flow vascular access, decreased vascular access flow was observed after the procedure. The average flow reduction after aneurysmorrhaphy was 2,197 mL/minute. Postoperative bleeding and infection necessitating surgical revision occurred in three (4.8%) and three (4.8%) patients respectively. Reinforced aneurysmorrhaphy with an external mesh prosthesis is an effective method for treating true aneurysmal haemodialysis AV access, with excellent long-term patency and minimal complications due to infection. Copyright © 2014 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Prevention of extravasation injuries secondary to doxorubicin.

PubMed

Linder, R M; Upton, J

1985-03-01

Intravenously administered drugs with potentially devastating consequences should be given only by personnel highly knowledgeable regarding the side effects and skilled in intravenous cannulation. A strict protocol should be followed. The earliest signs heralding extravasation should be recognized and infusion discontinued immediately. If extravasation occurs, prompt surgical consultation is necessary. Injection into the volar wrist, dorsum of the hand, and antecubital fossa should always be avoided. Polyethylene catheters are preferable to butterfly needles for administering chemotherapeutic agents. A careful history of the venous problems of patients who require long-term therapy should be maintained in their chart. Ideally, vascular access should avoid these problems.

Vascular Access Outcomes Reported in Maintenance Hemodialysis Trials: A Systematic Review.

PubMed

Viecelli, Andrea K; O'Lone, Emma; Sautenet, Benedicte; Craig, Jonathan C; Tong, Allison; Chemla, Eric; Hooi, Lai-Seong; Lee, Timmy; Lok, Charmaine; Polkinghorne, Kevan R; Quinn, Robert R; Vachharajani, Tushar; Vanholder, Raymond; Zuo, Li; Irish, Ashley B; Mori, Trevor A; Pascoe, Elaine M; Johnson, David W; Hawley, Carmel M

2018-03-01

Many randomized controlled trials have been performed with the goal of improving outcomes related to hemodialysis vascular access. If the reported outcomes are relevant and measured consistently to allow comparison of interventions across trials, such trials can inform decision making. This study aimed to assess the scope and consistency of vascular access outcomes reported in contemporary hemodialysis trials. Systematic review. Adults requiring maintenance hemodialysis. All randomized controlled trials and trial protocols reporting vascular access outcomes identified from ClinicalTrials.gov, Embase, MEDLINE, and the Cochrane Kidney and Transplant Specialized Register from January 2011 to June 2016. Any hemodialysis-related intervention. The frequency and characteristics of vascular access outcome measures were analyzed and classified. From 168 relevant trials, 1,426 access-related outcome measures were extracted and classified into 23 different outcomes. The 3 most common outcomes were function (136 [81%] trials), infection (63 [38%]), and maturation (31 [18%]). Function was measured in 489 different ways, but most frequently reported as "mean access blood flow (mL/min)" (37 [27%] trials) and "number of thromboses" (30 [22%]). Infection was assessed in 136 different ways, with "number of access-related infections" being the most common measure. Maturation was assessed in 44 different ways at 15 different time points and most commonly characterized by vein diameter and blood flow. Patient-reported outcomes, including pain (19 [11%]) and quality of life (5 [3%]), were reported infrequently. Only a minority of trials used previously standardized outcome definitions. Restricted sampling frame for feasibility and focus on contemporary trials. The reporting of access outcomes in hemodialysis trials is very heterogeneous, with limited patient-reported outcomes and infrequent use of standardized outcome measures. Efforts to standardize outcome reporting for vascular access are critical to optimizing the comparability, reliability, and value of trial evidence to improve outcomes for patients requiring hemodialysis. Copyright © 2017 National Kidney Foundation, Inc. All rights reserved.

Prospective Durability Testing of a Vascular Access Phantom

DTIC Science & Technology

2010-09-01

ultrasound guidance when obtaining central venous access.19,20 The increasing use of ultrasound guidance for vascular access has created an educational...with difficult intravenous access. Ann Emerg Med. 2005;46:456-61. 7. Gallieni M, Cozzolino M. Uncomplicated central vein catheterization of high risk...al. Randomized, controlled clinical trial of point-of-care limited ultrasonography assistance of central venous cannulation: The third sonography

64-slice MDCT angiography of upper extremity in assessment of native hemodialysis access.

PubMed

Wasinrat, Jitladda; Siriapisith, Thanongchai; Thamtorawat, Somrach; Tongdee, Trongtum

2011-01-01

To compare multidetector row computed tomographic (MDCT) angiography with conventional digital subtraction angiography (DSA) in the evaluation of vascular access stenoses in hemodialysis patients. Twenty-one consecutive patients were imaged with MDCT angiography and subsequent DSA. The superficial vein of leg was used as the route for intravenous administration. The vascular stenosis was assessed in not significant (<50% stenosis), moderate stenosis (50%-74% stenosis), severe stenosis (75%-99%), and total occlusion (100%). The accuracy, sensitivity, specificity, positive, and negative predictive values were calculated for significant vascular stenosis using DSA as the standard reference. The sensitivity and specificity of MDCT angiography for the detection of significant hemodialysis vascular access were 100% (95% CI, 89.3%-100%) and 94.8% (95% CI, 89.1%-97.6%), respectively. The positive and negative predictive values were 84.2% (95% CI, 68.1%-93.4%) and 100% (95% CI, 95.8%-100%), respectively. The accuracy of MDCT angiography for detection of significant stenoses was 95.9% (95% CI, 91.4%-97.0%). MDCT angiography provides excellent correlation in vascular stenosis as compared with DSA in hemodialysis access. Complete assessment of entire vascular segments could be performing with MDCT angiography in planning before endovascular intervention or surgical correction.

Regionalization of services improves access to emergency vascular surgical care.

PubMed

Roche-Nagle, G; Bachynski, K; Nathens, A B; Angoulvant, D; Rubin, B B

2013-04-01

Management of vascular surgical emergencies requires rapid access to a vascular surgeon and hospital with the infrastructure necessary to manage vascular emergencies. The purpose of this study was to assess the impact of regionalization of vascular surgery services in Toronto to University Health Network (UHN) and St Michael's Hospital (SMH) on the ability of CritiCall Ontario to transfer patients with life- and limb-threatening vascular emergencies for definitive care. A retrospective review of the CritiCall Ontario database was used to assess the outcome of all calls to CritiCall regarding patients with vascular disease from April 2003 to March 2010. The number of patients with vascular emergencies referred via CritiCall and accepted in transfer by the vascular centers at UHN or SMH increased 500% between 1 April 2003-31 December 2005 and 1 January 2006-31 March 2010. Together, the vascular centers at UHN and SMH accepted 94.8% of the 1002 vascular surgery patients referred via CritiCall from other hospitals between 1 January 2006 and 31 March 2010, and 72% of these patients originated in hospitals outside of the Toronto Central Local Health Integration Network. Across Ontario, the number of physicians contacted before a patient was accepted in transfer fell from 2.9 ± 0.4 before to 1.7 ± 0.3 after the vascular centers opened. In conclusion, the vascular surgery centers at UHN and SMH have become provincial resources that enable the efficient transfer of patients with vascular surgical emergencies from across Ontario. Regionalization of services is a viable model to increase access to emergent care.

Percutaneous management of vascular access in transfemoral transcatheter aortic valve implantation

PubMed Central

Dato, Ilaria; Burzotta, Francesco; Trani, Carlo; Crea, Filippo; Ussia, Gian Paolo

2014-01-01

Transcatheter aortic valve implantation (TAVI) using stent-based bioprostheses has recently emerged as a promising alternative to surgical valve replacement in selected patients. The main route for TAVI is retrograde access from the femoral artery using large sheaths (16-24 F). Vascular access complications are a clinically relevant issue in TAVI procedures since they are reported to occur in up to one fourth of patients and are strongly associated with adverse outcomes. In the present paper, we review the different types of vascular access site complications associated with transfemoral TAVI. Moreover, we discuss the possible optimal management strategies with particular attention to the relevance of early diagnosis and prompt treatment using endovascular techniques. PMID:25228962

[A Project to Reduce the Occlusion Rate in Hemodialysis Arteriovenous Access].

PubMed

Huang, Jia-Ling; Jang, Jeng-Fong; Lee, Kun-Feng; Shie, Yu-Ting; Jin, Mei-Hua

2015-06-01

Vascular occlusions in patients frequently necessitate that duty nurses work overtime to manage related vascular problems. For patients, vascular occlusions require invasive treatments that are painful, take time to heal, and increase anxiety. Furthermore, vascular occlusions seriously influence the effectiveness of hemodialysis. This project worked to reduce the rates of occlusion from 18.6% to < 15% for hemodialysis arteriovenous grafts (AVGs) and from 5.2% to < 2.6% for arteriovenous fistulas (AVFs). This project was conducted between September 1st, 2012 and July 31th, 2013. Our approach used a retrospective study, literature review, meeting discussions, and data compilation. The four main problems identified as associated with occlusion were: (1) low blood pressure during hemodialysis; (2) successive fistula puncture sites were located too close to one another; (3) abnormal blood flow; and (4) poor moisture control. Our solutions included: 1) adjusting and creating forms; 2) adjusting related nursing procedures; and 3) organizing a related lecture for our department. The occlusion rates of AVG and AVF decreased from 18.6% to 7.4% and 5.2% to 0.9%, respectively. We significantly reduced AVG and AVF occlusion rates by using simple methods such as using a tourniquet ruler, designing big-print, illustrated patient instruction sheets on preventing low blood pressure, creating a simplified fistula puncture site series chart, creating a moisture control card, and scheduling follow-up visits for patients with abnormal blood flow at the OPD. This project provides a reference for other hemodialysis departments.

Adoption and application in Italy of the principal guidelines and international recommendations on venous access.

PubMed

Spina, Rosario; Mussa, Baudolino; Tollapi, Lara; Conti, Fabio; Cortesi, Enrico; Verna, Roberto

2018-06-01

Vascular access is the commonest invasive procedure in secondary care. Vascular access is understood as being access to the bloodstream of acute and chronic patients for diagnostic and therapeutic purposes such as blood sampling, vessel pressure monitoring, fluid infusions (blood transfusions, parenteral nutrition), pharmacological treatments (e.g. antibiotic therapies, chemotherapy, analgesic therapies) or apheresis/dialysis through catheters that may remain in the vessels for weeks or months. There is a wide variety of options available for venous access. Device selection for venous access must be adapted to the patient's needs, and to the type, duration and frequency of the infusion. The scenario is rapidly evolving and hence treatments such as cancer chemotherapy, total parenteral nutrition, long-term parenteral antimicrobial therapies are increasing not only in hospitalized patients, but also in contexts other than traditional ones, such as local care, in response to needs related to healthcare expenditure or patients' needs. This paper originates from the idea of a multidisciplinary group of experts to analyze the main, most recent international guidelines and recommendations on vascular access and to evaluate its implementation in Italy. It often happens that documents acquired in different contexts, however extraordinarily effective and exhaustive, are difficult to apply in contexts where the healthcare organization, professional resources, communication dynamics and regulations are different. The consequence is a progressive departure from international standards and evidence-based medicine, which is particularly burdensome in sectors (such as vascular access and devices used for access) where technological innovation requires constant updating, alignment and method sharing. The work motivation of this group of authors, which sees its final finding in the welfare standards and criteria of appropriateness contained in this document, lies in the particular ongoing and future Italian epidemiological scenario and in the assessments of health economics that demand conscious and appropriate decisions in the interest of the citizen and the healthcare system. The vascular access field is undergoing a veritable revolution; once upon a time the leading lights were those who possessed the best technical skills, the best manual skills, whereas nowadays vascular access decisions are strategic decisions involving specially trained health professionals, able to assess complex interactions and work in teams. There is a strong cultural need, not only with regard to technical aspects, but also for the execution of procedures in daily clinical practice that comply with the recommendations set out in the guidelines published and elaborated by public and private bodies and institutions, as well as by scientific societies and recognized technical and scientific associations. This document is not a manual on vascular access for consultation by all those who intend to go deeper into operating aspects (selection of the device, implantation and management), but a reflection on the most recent pointers in the field of vascular access within Italy's complex healthcare situation.

Primary patency rate of native AV fistula: long term follow up

PubMed Central

GH, Kazemzadeh; MHS, Modaghegh; H, Ravari; M, Daliri; L, Hoseini; M, Nateghi

2012-01-01

The number of end stage of renal disease patients that need dialysis or renal transplantation increased in the world. Insertion and maintenance functional vascular access remain the challenging problem. Arteriovenous fistula is the common access for dialysis but complication and its failure is the main problem. The aim of this study is to evaluate patients with arteriovenous fistula during 4 years and describe the probable influenced factors on fistula patency. In this analytical descriptive study, we fallowed 245 patients during 4 years and evaluated them for primary failures and effective factors on vascular patency. The patients were asked about demographic data, how to caring condition arteriovenous fistula, dialysis and complications. The mean age of the patients was 47.77 years. The underline diseases were hypertension (43.3%), hypertension and diabetes mellitus (21.2%) and diabetes mellitus (4.5%). According Log rank test there were meaningful results between arteriovenous patency with sex and dialysis (P < 0.05). Our result of primary patency at 6 months, 1, 2, 3 and 4 years for all patients were 79.5%, 70%, 65%, 60.5% and 48%. Our study showed dialysis could increase the fistula patency rate. Other factors were not associated with primary patency. It seems ESRD patients undergoing dialysis have better fistula patency, may be due to homeostasis abnormalities induced by their particular conditions. PMID:22567178

Vascular Access System for Continuous Arterial Infusion of a Protease Inhibitor in Acute Necrotizing Pancreatitis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ganaha, Fumikiyo; Yamada, Tetsuhisa; Yorozu, Naoya

1999-09-15

We used a vascular access system (VAS) for continuous arterial infusion (CAI) of a protease inhibitor in two patients with acute necrotizing pancreatitis. The infusion catheter was placed into the dorsal pancreatic artery in the first patient and into the gastroduodenal artery in the second, via a femoral artery approach. An implantable port was then connected to the catheter and was secured in a subcutaneous pocket prepared in the right lower abdomen. No complications related to the VAS were encountered. This system provided safe and uncontaminated vascular access for successful CAI for acute pancreatitis.

Vascular closure devices in stroke patients receiving tissue plasminogen activator: A retrospective analysis from an academic tertiary medical center and a teaching community hospital stroke database.

PubMed

Patil, Mangaladevi S; Jayaraman, Mahesh V; Ahn, Sun H

2017-06-01

To determine the safety and effectiveness of vascular closure devices in prevention of access site complications in acute stroke patient receiving intravenous (IV) and/or intra-arterial (IA) IV tissue plasminogen activator (tPA). All patients with acute stroke onset treated with IV and/or IA tPA closed with vascular closure device and adult age (>18 years) were identified from an academic tertiary medical center and a teaching community hospital stroke database for 9 years (from March 2005 to June 2014). A total of 69 patients were included in the study. The mean age was 68.86±16.70 years and 49.2% female. All accesses were under fluoroscopic guidance into the right common femoral artery. We observed a 5.8% complication rate in patients receiving IV and/or IA tPA closed with vascular closure device. Access site complications included 3 cases of hematoma and 1 case of residual oozing. One patient required transfusion due to access site hematoma. Three patients were on aspirin and heparin and 1 was on no prior anticoagulation. Vascular closure device access site hemorrhagic complication rate in those receiving IV and/or IA tPA is low and similar to reported rates in those not receiving thrombolytic therapy. Vascular closure device use in patients receiving thrombolytic therapy is safe and effectively achieves hemostasis. Copyright © 2017 Elsevier B.V. All rights reserved.

Vascular access complications in patients undergoing percutaneous procedures in hemodynamics: a scoping review.

PubMed

Reich, Rejane; Rabelo-Silva, Eneida Rejane; Santos, Simone Marques Dos; Almeida, Miriam de Abreu

2018-06-07

To map the production of knowledge on vascular access complications in patients undergoing percutaneous procedures in hemodynamic laboratories. Scoping review study. The search strategy was developed in three stages, considering the period from July 2005 to July 2015 in the PubMed, CINAHL, Scopus, and LILACS databases. The collected data were analyzed and summarized in a narrative form. One-hundred twenty-eight publications that made it possible to map the contexts of study of complications, occurrence according to access routes, as well as an understanding of diagnosis and clinical management, were included. Three theme categories were identified: complications; predictive factors; and diagnosis/treatment. Vascular access site complications range according to the access route used. Knowledge of factors that permeate the occurrence of these events may contribute to early detection, planning, and monitoring of the care implemented.

[Value of preserved saphenous vein graft for the creation of access ports in hemodialyzed patients: report of 309 cases].

PubMed

Schneider, Marc; Barrou, Benoît; Cluzel, Philippe; Hamani, Aziz; Bitker, Marc-Olivier; Richard, François

2003-09-01

Biological grafts are rarely used for the creation of vascular access, despite their many advantages. Our group prefers to use distal vascular accesses with interposition of a biological graft when direct access cannot be achieved. The objective of this study was to determine the long-term patency and the complication rate of a series of 309 vascular access procedures using a preserved saphenous (PS) vein homograft. 410 (27%) of the 1,500 vascular access procedures performed by our group required the use of a graft, including 376 PS vein homografts (25%). This retrospective study comprised complete data collection for 309 arteriovenous fistulas (AVF) using preserved saphenous (PS) vein graft in the forearm performed in 267 patients between 1985 and 2000. Primary patency was defined as the interval between creation of the vascular access and the first complication requiring surgical or radiological correction; secondary patency was defined as the interval between creation and loss of the graft, with or without revision of the fistula. Survival rates were calculated according to the Kaplan-Meier method. Inter-group comparison was performed by the Logrank test and analysis of variance was performed by logistic regression. Primary patency rates were 77%, 40% and 27% at 1,2 and 5 years, respectively. Secondary patency rates were 79% and 47% at 1 year and 5 years, respectively. The thrombosis rate was 42%. Two episodes of thrombosis occurred in 25% of grafts and 3 episodes were observed in 10% of cases. Infection rates were 1.9% postoperatively and 5% after dialysis, respectively. An aneurysm occurred on 10% of grafts. The operator's experience (RR = 1.58; p < 0.05) and diabetic nephropathy (RR = 1.89; p = 0.059) significantly influenced graft patency. In contrast, the position of the graft, the fact that it crossed the elbow joint, and the site of the arterial anastomosis did not have any negative impact on graft patency. Preservation of the patient's vascular capital is an essential objective in patients with chronic renal insufficiency, which is sometimes difficult to reconcile with the need to create vascular accesses with a long life span. The strategic choice between a distal access requiring a graft and a direct proximal access depends on the clinical context: cardiac function, waiting list for renal transplantation. Our preferred material in the case of bypass graft is the PS graft, as it presents the same resistance and the same patency rates as synthetic grafts, without the associated septic complications. The PS vein graft is a good material for the creation of vascular accesses with similar patency rates to those of prosthetic grafts. Vein grafts present a number of advantages, particularly a greater ease of use facilitating distal implantation of the graft and a low infection rate.

Selective Angiography Using the Radiofrequency Catheter: An Alternative Technique for Mapping and Ablation in the Aortic Cusps.

PubMed

Roca-Luque, Ivo; Rivas, Nuria; Francisco, Jaume; Perez, Jordi; Acosta, Gabriel; Oristrell, Gerard; Terricabres, Maria; Garcia-Dorado, David; Moya, Angel

2017-01-01

Ablation in aortic cusps could be necessary in up to 15% of the patients, especially in para-Hisian atrial tachycardia and ventricular arrhythmias arising from outflow tracts. Risk of coronary damage has led to recommendation of systematic coronary angiography (CA) during the procedure. Other image tests as intravascular (ICE) or transesophageal echocardiography (TEE) have been proposed. Both methods have limitations: additional vascular access for ICE and need for additional CA in some patients in case of TEE. We describe an alternative method to assess relation of catheter tip and coronary ostia during ablation in aortic cusps without additional vascular accesses by performing selective angiography with the ablation catheter. We prospectively evaluated 12 consecutive patients (69.3 ± 8.5, 6 female) who underwent ablation in right (1), left (5), and noncoronary cusps (6). We performed angiography through the ablation cooled tip radiofrequency catheter at the ablation site. Ablation was effective in 91.6% of the patients (3 patients needed additional ablation out of coronary cusps: pulmonary cusp, right ventricular outflow tract (RVOT), and coronary sinus and 1 patient underwent a second procedure because recurrence). No complications occurred neither during procedure nor follow-up (6.2 ± 3.8 months). No technical problems occurred with the ablation catheter after contrast injection. Selective angiography through a cooled-tip radiofrequency ablation catheter is feasible to assess relation of coronary ostia and ablation site when ablation in aortic cusps. It allows continuous real-time assessment of this relation, avoids the need for additional vascular accesses and no complications occurred in our series. © 2016 Wiley Periodicals, Inc.

Nursing Care for Patients with Synthetic Arteriovenous Grafts.

PubMed

Gilliland, Michelle; Brown, Jami S; Pryor, Lillian

2017-01-01

Dealing with a growing older adult patient population, keeping pace with current guidelines, and adhering to new recommendations is a perpetual endeavor for healthcare professionals. Because determining the best access for individual patients is not always obvious, vascular access is a challenging aspect of patient care. This article presents information on the ever-evolving and improving world of vascular access, specifically synthetic grafts. Copyright© by the American Nephrology Nurses Association.

Design and rationale of the AngioSeal versus the Radial approach In acute coronary SyndromE (ARISE) trial: a randomized comparison of a vascular closure device versus the radial approach to prevent vascular access site complications in non-ST-segment elevation acute coronary syndrome patients.

PubMed

de Andrade, Pedro Beraldo; E Mattos, Luiz Alberto Piva; Tebet, Marden André; Rinaldi, Fábio Salerno; Esteves, Vinícius Cardozo; Nogueira, Ederlon Ferreira; França, João Ítalo Dias; de Andrade, Mônica Vieira Athanazio; Barbosa, Robson Alves; Labrunie, André; Abizaid, Alexandre Antônio Cunha; Sousa, Amanda Guerra de Moraes Rego

2013-12-18

Arterial access is a major site of bleeding complications after invasive coronary procedures. Among strategies to decrease vascular complications, the radial approach is an established one. Vascular closure devices provide more comfort to patients and decrease hemostasis and need for bed rest. However, the inconsistency of data proving their safety limits their routine adoption as a strategy to prevent vascular complications, requiring evidence through adequately designed randomized trials. The aim of this study is to compare the radial versus femoral approach using a vascular closure device for the incidence of arterial puncture site vascular complications among non-ST-segment elevation acute coronary syndrome patients submitted to an early invasive strategy. ARISE is a national, multicenter, non-inferiority randomized clinical trial. Two hundred patients with non-ST-segment elevation acute coronary syndrome will be randomized to either radial or femoral access using a vascular closure device. The primary outcome is the occurrence of vascular complications at an arterial puncture site 30 days after the procedure, including major bleeding, retroperitoneal hematoma, compartment syndrome, hematoma ≥ 5 cm, pseudoaneurysm, arterio-venous fistula, infection, limb ischemia, arterial occlusion, adjacent nerve injury or the need for vascular surgical repair. Enrollment was initiated in September 2012, and until October 2013 91 patients were included. The inclusion phase is expected to last until the second half of 2014. The ARISE trial will help define the role of a vascular closure device as a bleeding avoidance strategy in patients with NSTEACS. ClinicalTrials.gov identifier: NCT01653587.

Cost analysis of the Hemodialysis Reliable Outflow (HeRO) Graft compared to the tunneled dialysis catheter.

PubMed

Al Shakarchi, Julien; Inston, Nicholas; Jones, Robert G; Maclaine, Grant; Hollinworth, David

2016-04-01

In end-stage renal disease patients with central venous obstruction, who have limited vascular access options, the Hemodialysis Reliable Outflow (HeRO) Graft is a new alternative with a lower incidence of complications and longer effective device life compared to tunneled dialysis catheters (TDCs). We undertook an economic analysis of introducing the HeRO Graft in the UK. A 1-year cost-consequence decision analytic model was developed comparing management with the HeRO Graft to TDCs from the perspective of the National Health Service in England. The model comprises four 3-month cycles during which the vascular access option either remains functional for hemodialysis or fails, patients can experience access-related infection and device thrombosis, and they can also accrue associated costs. Clinical input data were sourced from published studies and unit cost data from National Health Service 2014-15 Reference Costs. In the base case, a 100-patient cohort managed with the HeRO Graft experienced 6 fewer failed devices, 53 fewer access-related infections, and 67 fewer device thromboses compared to patients managed with TDCs. Although the initial device and placement costs for the HeRO Graft are greater than those for TDCs, savings from the lower incidence of device complications and longer effective device patency reduces these costs. Overall net annual costs are £2600 for each HeRO Graft-managed patient compared to TDC-managed patients. If the National Health Service were to reimburse hemodialysis at a uniform rate regardless of the type of vascular access, net 1-year savings of £1200 per patient are estimated for individuals managed with the HeRO Graft. The base case results showed a marginal net positive cost associated with vascular access with the HeRO Graft compared with TDCs for the incremental clinical benefit of reductions in patency failures, device-related thrombosis, and access-related infection events in a patient population with limited options for dialysis vascular access. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

[The management of arteriovenous fistula for dialysis patients].

PubMed

Lopez, Teodoro; Casino, Francesco

2014-01-01

A well-functioning vascular access is a basic requirement for a good dialysis treatment. Among the vascular accesses, the Artero-venous fistula (FAV) with native vessels is preferred for increasing survival rate, reducing risk of infection and with fewer complications. This review examines some aspects concerning the preparation and the surveillance of AVF.

A balloon-expandable sheath facilitates transfemoral TAVR in patients with peripheral vascular disease and tortuosity.

PubMed

Goldsweig, Andrew M; Faheem, Osman; Cleman, Michael W; Forrest, John K

2015-06-01

We sought to perform transcatheter aortic valve replacement (TAVR) via the transfemoral approach in patients with peripheral arterial disease (PAD), small caliber ileofemoral vessels and vascular tortuosity. For patients with increased surgical risk, TAVR is associated with a higher 1-year survival rate than surgical aortic valve replacement (SAVR). Transfemoral vascular access for TAVR results in superior outcomes versus procedures performed via other routes in terms of mortality, morbidity and healthcare economics. In many patients, the ability to safely perform the procedure via the transfemoral approach is limited by narrow, diseased and tortuous ileofemoral vasculature. We employed the SoloPath Balloon Expandable TransFemoral Access System (Terumo Med. Corp., Tokyo, Japan) to perform transfemoral TAVR in five patients with PAD, small caliber ileofemoral vessels and vascular tortuosity. We report our experience using this balloon-expandable sheath during 5 cases of transfemoral TAVR in patients with inhospitable ileofemoral vasculature of mean diameter ⩽ 5.8 mm. The unexpanded sheath's malleable structure and hydrophilic coating permitted deployment despite severe stenoses and tortuosity. Subsequent inflation to 18 Fr facilitated successful TAVR. Postprocedural angiography demonstrated no significant vascular access complications. In one case, the entire procedure was performed percutaneously, without common femoral artery surgical cutdown. The SoloPath sheath system permits transfemoral TAVR in patients with PAD small caliber ileofemoral vessels and vascular tortuosity. The transfemoral balloon-expandable sheath allowed these patients to avoid the increased morbidity and mortality risks associated with direct aortic or transapical access. © The Author(s), 2015.

Comparison of a novel real-time SonixGPS needle-tracking ultrasound technique with traditional ultrasound for vascular access in a phantom gel model.

PubMed

Kopac, Daniel S; Chen, Jerry; Tang, Raymond; Sawka, Andrew; Vaghadia, Himat

2013-09-01

Ultrasound-guided percutaneous vascular access for endovascular procedures is well established in surgical practice. Despite this, rates of complications from venous and arterial access procedures remain a significant cause of morbidity. We hypothesized that the use of a new technique of vascular access using an ultrasound with a novel needle-guidance positioning system (GPS) would lead to improved success rates of vascular puncture for both in-plane and out-of-plane techniques compared with traditional ultrasound. A prospective, randomized crossover study of medical students from all years of medical school was conducted using a phantom gel model. Each medical student performed three ultrasound-guided punctures with each of the four modalities (in-plane no GPS, in-plane with GPS, out-of-plane no GPS, out-of-plane with GPS) for a total of 12 attempts. The success or failure was judged by the ability to aspirate a simulated blood solution from the model. The time to successful puncture was also recorded. A poststudy validated NASA Task Load Index workload questionnaire was conducted to assess the student's perceptions of the two different techniques. A total of 30 students completed the study. There was no significant difference seen in the mean times of vascular access for each of the modalities. Higher success rates for vascular access using the GPS for both the in-plane (94% vs 91%) and the out-of-plane (86% vs 70%) views were observed; however, this was not statistically significant. The students perceived the mental demand (median 12.0 vs 14.00; P = .035) and effort to be lower (mean 11.25 vs 14.00; P = .044) as well as the performance to be higher (mean 15.50 vs 14.00; P = .041) for the GPS vs the traditional ultrasound-guided technique. Students also perceived their ability to access vessels increased with the aid of the GPS (7.00 vs 6.50; P = .007). The majority of students expressed a preference for GPS (26/30, 87%) as opposed to the traditional counterpart. Use of the novel SonixGPS needle-tracking ultrasound system (UltraSonix, Richmond, BC, Canada) was not associated with a higher success rate of vascular puncture compared with the traditional ultrasound-guided technique. Assessment of mental task load significantly favored the use of the ultrasound GPS over the traditional ultrasound technique. Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Epidemiological perspective on infections in chronic dialysis patients.

PubMed

Bloembergen, W E; Port, F K

1996-07-01

Infectious complications are a source of substantial morbidity and a common cause of death among dialysis patients. This article considers the magnitude and impact of the problem of infection among patients treated with hemodialysis (HD) and peritoneal dialysis (PD) using data from national registries and large cohort studies of patients with end-stage renal disease (ESRD). United States Renal Data System (USRDS) data indicate that in the United States for years 1991 to 1992, infection accounted for 12% of all deaths among HD patients and 15% of all deaths among PD patients. Septicemia was the underlying cause in 76% of these infectious deaths among HD patients, of which the vascular access, peritonitis, peripheral vascular disease, and other causes accounted for 12%, 5%, 24%, and 59% respectively. Among PD patients, septicemia accounted for 79% of infectious deaths. Of these deaths attributable to septicemia, peritonitis, peripheral vascular disease, and other causes were reported as the cause in 35%, 23%, and 41% respectively. Infection is also a major cause of morbidity in the dialysis population. Among HD patients, an average of 7.6 bacteremic episodes per 100 patient years (0.076 per year) has been described, of which 48% were associated with access infections. Among PD patients, studies have reported peritonitis rates ranging from 1 in 7.6 to 21.5 months (0.56 to 1.58 per patient year) and exit and/or tunnel infections occurring at a rate of 0.6 episodes per year. The known predictors of infectious complications among these populations are reviewed.

Vascular access choice in incident hemodialysis patients: a decision analysis.

PubMed

Drew, David A; Lok, Charmaine E; Cohen, Joshua T; Wagner, Martin; Tangri, Navdeep; Weiner, Daniel E

2015-01-01

Hemodialysis vascular access recommendations promote arteriovenous (AV) fistulas first; however, it may not be the best approach for all hemodialysis patients, because likelihood of successful fistula placement, procedure-related and subsequent costs, and patient survival modify the optimal access choice. We performed a decision analysis evaluating AV fistula, AV graft, and central venous catheter (CVC) strategies for patients initiating hemodialysis with a CVC, a scenario occurring in over 70% of United States dialysis patients. A decision tree model was constructed to reflect progression from hemodialysis initiation. Patients were classified into one of three vascular access choices: maintain CVC, attempt fistula, or attempt graft. We explicitly modeled probabilities of primary and secondary patency for each access type, with success modified by age, sex, and diabetes. Access-specific mortality was incorporated using preexisting cohort data, including terms for age, sex, and diabetes. Costs were ascertained from the 2010 USRDS report and Medicare for procedure costs. An AV fistula attempt strategy was found to be superior to AV grafts and CVCs in regard to mortality and cost for the majority of patient characteristic combinations, especially younger men without diabetes. Women with diabetes and elderly men with diabetes had similar outcomes, regardless of access type. Overall, the advantages of an AV fistula attempt strategy lessened considerably among older patients, particularly women with diabetes, reflecting the effect of lower AV fistula success rates and lower life expectancy. These results suggest that vascular access-related outcomes may be optimized by considering individual patient characteristics. Copyright © 2015 by the American Society of Nephrology.

Increased use of catheters as vascular access: is it justified by patients' clinical conditions?

PubMed

Di Benedetto, A; Basci, A; Cesare, S; Marcelli, D; Ponce, P; Richards, N

2007-01-01

Over the last years many technical improvements have been made in hemodialysis treatment. Vascular access (VA) still remains an important problem. Although the use of indwelling vascular catheters is discouraged, in Europe there is an increasing use of them. The K/DOQI Guidelines recommend a native arteriovenous fistula (AVF) as VA of choice. As reported by DOPPS, there is considerable geographic variation in the distribution of type of VA used amongst hemodialysis patients. The aim of this study was to evaluate the time patients in four European countries have to wait before undergoing their first surgery for VA (AVF or graft). All incident patients admitted to HD clinics located in Turkey, Italy, the UK and Portugal of the European FME clinics network between October 1, 2002 and September 30, 2004 were considered. Data were gained from the Clinical Database EuCliD. 2,152 patients (males 55.9%, mean age 62.5+/-15.7 years, diabetics 27%) were selected. Italy and Portugal had a higher proportion of elderly patients. At time of admission, the proportion of patients starting dialysis with AVF ranged between 23% and 60% from Turkey to Italy respectively. Patients with an indwelling catheter at admission are expected to undergo VA surgery as soon as possible. After 3 months of follow-up, about 75% of all patients had undergone surgery, however in the UK less than 50% of the patients had had a VA procedure. Overall, males have significantly higher probability of undergoing surgery, whilst elderly patients have a lower probability (27% and 14% respectively). Significant differences exist between countries in the time interval from referral to creation of VA. Health care system related problems seem to be the major reason to explain such differences. Patients in the UK have longer waiting times than the other countries studied.

Variation in use of technology among vascular access specialists: an analysis of the PICC1 survey.

PubMed

Chopra, Vineet; Kuhn, Latoya; Ratz, David; Winter, Suzanne; Carr, Peter J; Paje, David; Krein, Sarah L

2017-05-15

While the use of technologies such as ultrasound and electrocardiographic (ECG) guidance systems to place peripherally inserted central catheters (PICCs) has grown, little is known about the clinicians who use these tools or their work settings. Using data from a national survey of vascular access specialists, we identified technology users as PICC inserters that: (a) use ultrasound to find a suitable vein for catheter placement; (b) measure catheter-to-vein ratio; and (c) use ECG for PICC placement. Individual and organizational-level characteristics between technology users versus non-users were assessed. Bivariable comparisons were made using Chi-squared or Fisher's exact tests; two-sided alpha with p<0.05 was considered statistically significant. Of the 2762 PICC inserters who accessed the survey, 1518 (55%) provided information regarding technology use. Technology users reported greater experience than non-technology users, with a higher percentage stating they had placed >1000 PICCs (55% vs. 45%, p<0.001). A significantly greater percentage of technology users also reported being certified in vascular access by an external agency than non-technology users (75% vs. 63%, p<0.001). Technology users were more often part of vascular access teams with ≥10 members compared to non-technology users (35% vs. 22%, p<0.001). Some practices also varied between the two groups: for example, use of certain securement devices and dressings differed between technology users and non-users (p<0.001). Technology use by vascular access clinicians while placing PICCs is associated with clinician characteristics, work setting and practice factors. Understanding whether such differences influence clinical care or patient outcomes appears necessary.

Vascular Access Guidelines: Summary, Rationale, and Controversies.

PubMed

Sequeira, Adrian; Naljayan, Mihran; Vachharajani, Tushar J

2017-03-01

Dialysis vascular access management in the United States changed significantly after National Kidney Foundation-Kidney Disease Outcome Quality Initiative (NKF-KDOQI) clinical practice guidelines were first published in 1997. The Centers for Medicare and Medicaid Service adopted these guidelines and in collaboration with the End-Stage Renal Disease Networks established the Fistula First Breakthrough Initiative (FFBI) in 2003 to improve the rate of arteriovenous fistula use over arteriovenous graft and central venous catheter in the dialysis population. The implementation of guidelines and FFBI has led to a significant increase in the arteriovenous fistula use in the prevalent dialysis population. The guidelines are criticized for being opinion based and often impractical. Over the past 2 decades, the patient population undergoing dialysis has become older with complex comorbidities and challenges for creating an ideal vascular access. Advancing knowledge about access pathophysiology, improved treatment options, and improved process of care with team approach model point toward diminishing relevance of few of the existing guidelines. Moreover, several guidelines remain controversial and may be leading to clinical decisions that may be unfavorable to the patients. The review discusses the historical aspect of vascular access care in the United States and evolution of current practice standards and controversies surrounding few of these guidelines in the current time. Published by Elsevier Inc.

Reducing haemodialysis access infection rates.

PubMed

Dorman, Amanda; Dainton, Marissa

Infections are the second most common cause of vascular access loss in the long-term haemodialysis patient, and recent years have seen an increase in healthcare-associated infections (HCAIs) associated with vascular access (Suhail, 2009). There have been a number of drivers including publication guidelines (Department of Health, 2006; 2007) and local protocols providing evidence-based recommendations that, when implemented, can reduce the risk of these infections. In England, the selection of bloodstream infections caused by methicillin resistant staphylococcus aureus (MRSA) as a significant clinical outcome has led to a vast amount of work in this area. Root cause analysis of individual infections (by the clinical teams when these occur) in many specialities identified areas where practice could be improved, including practice relating to vascular access within the renal setting. Manufacturers have also supported this work by focusing on developing products that are designed to reduce the likelihood of infections occurring. One product identified and used within the NHS is Chloraprep.

The versatility of intraosseous vascular access in perioperative medicine: a case series.

PubMed

Anson, Jonathan A; Sinz, Elizabeth H; Swick, John T

2015-02-01

Intraosseous vascular access is a time-tested procedure that is reemerging in popularity. This is primarily a result of the emphasis on intraosseous access in the American Heart Association Guidelines for Cardiopulmonary Resuscitation and Advanced Cardiac Life Support. Modern intraosseous insertion devices are easy to learn and use, suggesting the possibility of use beyond the resuscitation setting. We present a case series of recent intraosseous insertions for a variety of indications by anesthesiologists at our institution to demonstrate the potential utility of this alternative access technique. Copyright © 2014 Elsevier Inc. All rights reserved.

Endovascular Creation of an Arteriovenous Fistula (endoAVF) for Hemodialysis Access: First Results.

PubMed

Radosa, Christoph Georg; Radosa, Julia Caroline; Weiss, Norbert; Schmidt, Christine; Werth, Sebastian; Hofmockel, Thomas; Plodeck, Verena; Gatzweiler, Christian; Laniado, Michael; Hoffmann, Ralf-Thorsten

2017-10-01

Surgical creation of a radiocephalic fistula is the gold standard of vascular access for hemodialysis. Recently, an endovascular approach for upper arm fistula creation (endoAVF) has been developed, which may be an alternative to open surgery. We describe a case series of eight cases showing feasibility, early complications and outcome of this novel treatment option. Between July 2015 and February 2016, we created an endoAVF in eight patients. Indications for endoAVF were confirmed by a multidisciplinary vascular board upon the exclusion for Cimino fistula candidates. Patients were suitable for the procedure after a pre-therapeutic ultrasound showed adequate brachial and ulnar vessels and no ipsilateral central venous stenosis. Patient characteristics, technical success, total patient radiation dose, complication rates, time to maturation of endoAVF and clinical effectiveness at six months were assessed retrospectively. Creation of endoAVF using the everlinQ endoAVF system (TVA Medical Inc., Austin, TX, USA) was successful in all eight cases. There were one minor intraprocedural complication and no postoperative complications. Median time to endoAVF maturation was 63 days (range 26-137 days). One patient was lost to follow-up after the first monitoring visit. In the remaining seven patients, hemodialysis was started without problems. Patency after 6 months was 100%. The endoAVF demonstrated to be feasible and safe for the creation of arteriovenous fistula suitable for hemodialysis access. Further studies with more patients and longer follow-up periods are needed to assess long-term outcomes and comparability to surgical dialysis access creation.

[Vascular steal syndrome due to the creation of an arteriovenous shunt for hemodialysis, patient information and nephrologist responsibility].

PubMed

Seidowsky, Alexandre; Vilaine, Eve; Adoff, Sarah; Dupuis, Emmanuel; Bidault, Caroline; Villain, Cédric; Coscas, Raphaël

2017-06-01

Although responsibility is a fundamental determinant in medical practice, physicians are generally unfamiliar with its principles. The same is true for disclosure requirements and requests for compensation in the event of physical injury. We report on a representative survey of iatrogenic complications that may arise after the implementation of vascular access for haemodialysis and that illustrate's the physician's responsibility and obligation to inform the patient. Vascular access steal syndrome is a serious complication of arteriovenous fistulas, and physicians may not be sufficiently aware of the likelihood of its occurrence. Diabetes (via medial calcific sclerosis) and placement in the brachial artery (with excessively high flow rates) are the main risk factors. The precariousness of vascular status in dialysis patients threatens to increase the incidence of this complication. The therapeutic challenge is to resolve ischemic events while maintaining vascular access. The presence of gangrene of the fingers is a formal indication for surgery. The borderline between therapeutic risk (the risk inherent in a medical procedure and which cannot be controlled) and liability for injury is blurred. The French Patient's Rights Act (voted on March 4th, 2002) emphasizes the physician's duty to inform the patient of treatment-associated risks and the fact that the physician now bears the burden of proof. We suggest that a patient information sheet on the benefits and risks of vascular access should be published on the French Society of Nephrology, Dialysis and Transplantation's website. Copyright © 2017 Société francophone de néphrologie, dialyse et transplantation. Published by Elsevier Masson SAS. All rights reserved.

Vascular access registry of Serbia: a 4-year experience.

PubMed

Jemcov, Tamara; Dimkovic, Nada

2017-02-01

Adequate and functional long-term vascular access (VA) is pivotal for the efficient hemodialysis (HD). It has been shown that the most reliable VA is autogenous arteriovenous fistulas (AVFs) as compared with arteriovenous grafts (AVGs) and vascular catheters (VCs). The vascular access register (VAR) has been established since 2010, and the 4-year trend of VA in Serbia is presented in this paper. All HD centers in Serbia provided their data by fulfilling the questionnaire that included prevalent and incident HD patients on December 31, 2010-1013. AVF is the most frequent prevalent VA (89.5-93.1 %) and also the most frequent newly created VA (87-89 %) during the observational period. The number of preemptive AVF is increasing, but it is still low (7.8 % in 2010 and 14.6 % in 2013). The percentage of incident AVG is constant (~3.4 %) as well as the number of permanent VC (8.2 % in 2010 and 7.8 % in 2013). The number of incident patients who started HD with AVF is decreasing (from 37 to 27 %), and the number of urgent start with VC is on the increase (from 63 to 73 %). In almost all relevant dialysis centers, vascular access is created by surgeons. Temporal VCs are placed by anesthesiologists (all centers), nephrologists (up to 25 % of centers) and vascular surgeons (up to 20 %). VCs are located mainly in jugular vein, but the number of femoral catheters remains high (up to 69 %). Although we have favorable data, the VAR is of a great importance and ensures continuous quality improvement.

Dialysis access: an increasingly important clinical issue.

PubMed

Gallieni, Maurizio; Martini, Alma; Mezzina, Nicoletta

2009-12-01

Dialysis access, including vascular access for hemodialysis and peritoneal access for peritoneal dialysis, is critical in the clinical care of patients with end-stage renal disease. It is associated with increases in morbidity, mortality, and health care costs. A number of problematic issues are involved, some of which are addressed in this paper with reference to the most recent publications, including: the inappropriately low prevalence of peritoneal dialysis in Western countries, which is relevant to access placement in the pre-dialysis stage; the excessively high use of central venous catheters in incident and prevalent dialysis patients; the diagnosis and treatment of steal syndrome; the advantages and limitations of antiplatelet therapy; and finally, the correct pre-operative evaluation and subsequent surveillance of the vascular access.

Hemodialysis patients' satisfaction and perspectives on complications associated with vascular access related interventions: are we listening?

PubMed

Kosa, Sarah D; Bhola, Cynthia; Lok, Charmaine E

2016-07-12

To understand the patient's perspective on complications associated with vascular access-related interventions. A multi-stage comprehensive questionnaire of over 150 items was administered to 140 in-center hemodialysis patients in a large, Toronto-based academic-based facility from May 1, 2011 until July 1, 2014. The questionnaire was divided into three domains: physical complications, disruption to routine, and infection. For each of the 12 prespecified vascular access interventions, there were 9 items about the associated complications. The level of bother associated with complications was measured using a 5-point Likert scale. The mean Likert value (5 = extremely bothered) for the physical complications domain was highest for grafts at 1.92, followed closely by fistulas at 1.87, and catheters at 1.56. The mean Likert value for the "disruption of routine" domain was highest for catheters at 1.44, followed by grafts at 1.37, and fistulas at 1.33. For infectious complications of all vascular access-related interventions the mean Likert value was highest at 1.76 for catheters as compared to fistulas at 1.23 and grafts at 1.22. For hemodialysis patients, the physical complications associated with needle cannulation of fistulas and grafts are a major source of dissatisfaction, while infectious complications, including catheter-related infections, are not a significant source of their concerns. Future research should focus on developing methods to effectively: (i) reduce the fear and pain associated with cannulation and (ii) educate patients about the risks associated with vascular access-related infection.

[Reason for "choosing" peritoneal dialysis: exhaustion of vascular access for hemodialysis?].

PubMed

Rocha, Paulo Novis; Sallenave, Mila; Casqueiro, Verena; Campelo Neto, Bolivar; Presídio, Sérgio

2010-03-01

Little is known about the prognosis of patients beginning peritoneal dialysis (PD) as their last alternative. To describe the clinical-demographic profile of patients switching from hemodialysis (HD) to PD, due to exhaustion of the HD vascular access, and the occurrence of peritonitis among them. Review of the medical records of all patients in the PD program of the Hospital Roberto Santos in the city of Salvador, state of Bahia, Brazil. The study comprised 22 patients (median age, 47.9 years), 54.5% of whom were men, 84.2%, black or mulattoes, and 68.2% originated from the inner Bahia state. Peritoneal dialysis was the initial modality of renal substitutive therapy (RST) in only four of those patients. The remaining 18 patients began RST through HD, mainly on an emergency basis and by using double-lumen catheter (DLC). In a median of 7.7 months on HD, most patients (64.7%) used four or more DLCs. In only 7/18 (39%) patients, the switch from HD to PD was based on the patient';s choice; in most cases, 11/18 (61%), the reason for switching to PD was exhaustion of HD vascular access. Peritonitis was more frequent in patients switching to PD due to exhaustion of HD vascular access than in the rest of the group. Initiating RST on an emergency basis through HD and using DLC may lead to a fast exhaustion of vascular access, leaving PD as the only viable option. This inadequate mode of patient "selection" for PD is associated with a higher risk for peritonitis.

Aneurysms in vascular access: state of the art and future developments.

PubMed

Inston, Nicholas; Mistry, Hiren; Gilbert, James; Kingsmore, David; Raza, Zahid; Tozzi, Matteo; Azizzadeh, Ali; Jones, Robert; Deane, Colin; Wilkins, Jason; Davidson, Ingemar; Ross, John; Gibbs, Paul; Huang, Dean; Valenti, Domenico

2017-11-17

A master class was held at the Vascular Access at Charing Cross (VA@CX2017) conference in April 2017 with invited experts and active audience participation to discuss arteriovenous (AV) vascular access aneurysms, a serious and common complication of vascular access (VA). The natural history of aneurysms in VA is poorly defined, and although classifications exist they are not uniformly applied in studies or clinical practice. True and pseudo aneurysms of AV access occur. Whilst an AV fistula by definition is an abnormal dilatation of a blood vessel, an agreed definition of 18 mm, or 3 times accepted maturation diameter, is proposed. The mechanism of aneurysmal dilatation is unknown but appears to be a combination of excessive external remodeling, wall changes due to injury, and obstruction of outflow. Diagnosis of AV aneurysms is based on physical examination and ultrasound. Venography and cross-sectional imaging may assist and be required for the investigation of outflow stenosis. Treatment of pseudo aneurysms and true aneurysms of VA (AVA) is not evidence-based, but relies on clinical experience and available facilities. In many AVA, a conservative approach with surveillance is suitable, although intervals and modalities are unclear. Avoidance of rupture is imperative and preemptive treatment should aim for access preservation, ideally with avoidance of prosthetic materials. Different techniques of aneurysmorrhaphy are described with good results in published series. Although endovascular approaches and stenting are described with good short-term results, issues with cannulation of stented areas occur and, while possible, this is not recommended, and long-term access revision is recommended.

Fiber Bragg grating based arterial localization device

NASA Astrophysics Data System (ADS)

Ho, Siu Chun Michael; Li, Weijie; Razavi, Mehdi; Song, Gangbing

2017-06-01

A critical first step to many surgical procedures is locating and gaining access to a patients vascular system. Vascular access allows the deployment of other surgical instruments and also the monitoring of many physiological parameters. Current methods to locate blood vessels are predominantly based on the landmark technique coupled with ultrasound, fluoroscopy, or Doppler. However, even with experience and technological assistance, locating the required blood vessel is not always an easy task, especially with patients that present atypical anatomy or suffer from conditions such as weak pulsation or obesity that make vascular localization difficult. With recent advances in fiber optic sensors, there is an opportunity to develop a new tool that can make vascular localization safer and easier. In this work, the authors present a new fiber Bragg grating (FBG) based vascular access device that specializes in arterial localization. The device estimates the location towards a local artery based on the bending of a needle inserted near the tissue surrounding the artery. Experimental results obtained from an artificial circulatory loop and a mock artery show the device works best for lower angles of needle insertion and can provide an approximately 40° range of estimation towards the location of a pulsating source (e.g. an artery).

CE: Original Research: Does Certification in Vascular Access Matter? An Analysis of the PICC1 Survey.

PubMed

Chopra, Vineet; Kuhn, Latoya; Vaughn, Valerie; Ratz, David; Winter, Suzanne; Moureau, Nancy; Meyer, Britt; Krein, Sarah

2017-12-01

: Background: Although certification by an accredited agency is often a practice prerequisite in health care, it is not required of vascular access specialists who insert peripherally inserted central catheters (PICCs). Whether certification is associated with differences in practice among inserters is unknown. The purpose of this study was to gather information regarding whether certified and noncertified PICC inserters differ with respect to their practices and views about PICC use. We conducted a national survey of vascular access specialists, identifying certified PICC inserters as those who had received board certification from the Association for Vascular Access, the Infusion Nurses Society, or both. The 76-item survey asked about PICC policies and procedures at respondents' facilities, use of insertion technologies, device management, management of complications, perceptions about PICC use, and relationships with other health care providers. Additional data about respondents, including years in practice and primary practice settings, were also gathered. Bivariable comparisons were made using χ tests; two-sided α with P ≤ 0.05 was considered statistically significant. Of the 1,450 respondents in the final sample, 1,007 (69%) said they were certified inserters and 443 (31%) said they were not. Significantly higher percentages of certified than noncertified inserters reported having practiced for five or more years (78% versus 54%) and having placed 1,000 or more PICCs (58% versus 32%). Significantly more certified than noncertified inserters also reported being the vascular access lead for their facility (56% versus 44%). Reported practice patterns for insertion, care, and management of PICCs varied based on certification status. Some evidence-based practices (such as the use of ultrasound to measure catheter-to-vein ratios) were more often reported by certified inserters, while others (such as the use of maximal sterile barriers during PICC insertion) were not. Asked about their perceptions of PICC use at their institution, certified inserters reported higher percentages of inappropriate insertion and removal than noncertified inserters. Certified PICC inserters appear to be a distinct group of vascular access specialists. A better understanding of how and why practices differ between certified and noncertified inserters is necessary to ensuring safer, high-quality patient care.

Interventional nephrology: Physical examination as a tool for surveillance for the hemodialysis arteriovenous access.

PubMed

Salman, Loay; Beathard, Gerald

2013-07-01

The prospective recognition of stenosis affecting dialysis vascular access and its prospective treatment is important in the management of the hemodialysis patient. Surveillance by physical examination is easily learned, easily performed, quickly done, and economical. In addition, it has a level of accuracy and reliability equivalent to other approaches that require special instrumentation. Physical examination should be part of any education to all hemodialysis care givers. This review presents the basic principles of physical examination of the hemodialysis vascular access and discusses the evidence behind its value.

Totally implanted ports: the trapezius approach in practice.

PubMed

Hill, Steve

Implanted ports (IPs) are an essential device for many patients who require long-term vascular access. IPs offer some advantages over other central venous access devices, such as lifestyle, body image benefits and lower infection rates. A typical implantation site for a port is the anterior chest wall. For some patients with breast cancer who have metastatic chest wall disease this site may lead to problems with the function of the device if disease spreads to the port site. One option for this patient group is to place the implanted port over the trapezius muscle. This article discusses six patients, all of whom had metastatic breast cancer with some degree of subcutaneous disease on the anterior chest wall. Three patients had received trapezius port placements and three had anterior chest wall placements. A retrospective review of the patients' medical records was undertaken from the time of insertion until removal or until the patient died. The anterior chest wall group of patients had their devices in for an average of 368 days vs 214 in the trapezius group. The total complications were higher in the anterior chest wall group (7 vs 2 in the trapezius group). Disease spread to two of the devices in the anterior chest wall group meaning the devices could no longer be used. The trapezius approach appears to be a safe and a reliable form of vascular access and may offer fewer complications than the traditional method of anterior chest wall placement when standard anterior chest wall approach is not suitable.

Vascular access site complication in transfemoral coronary angiography between uninterrupted warfarin and heparin bridging.

PubMed

Wongcharoen, Wanwarang; Pinyosamosorn, Kittipong; Gunaparn, Siriluck; Boonnayhun, Suchada; Thonghong, Tasalak; Suwannasom, Pannipa; Phrommintikul, Arintaya

2017-08-01

Warfarin discontinuation with heparin bridging is a common practice in patients receiving warfarin prior to elective coronary angiography (CAG). The uninterrupted warfarin strategy has been suggested to be alternative option for patients with high thromboembolic risk. Therefore, we aimed to assess the safety of elective transfemoral CAG during uninterrupted warfarin therapy compared to heparin bridging. This study was a randomized open-label design with blinded event evaluation. The 110 consecutive patients (age ≥ 18 years) receiving warfarin before the planned transfemoral CAG were randomly assigned to either heparin bridging or uninterrupted warfarin with targeted INR (2.0-3.0). The primary outcome was the incidence of major vascular access site complications. The baseline characteristics were comparable between two groups (mean age was 60.1 ± 7.8 years, 49 males). The mean INR on the day of CAG of heparin bridging and uninterrupted warfarin groups was 1.2 ± 0.3 and 2.2 ± 0.5 (P < 0.001). The major vascular access site complications occurred in 3 of 55 (5.5%) heparin-bridging patients and in none of 55 uninterrupted warfarin patients (P = 0.243). The total vascular access site complications occurred in 6 (10.9%) heparin-bridging and one (1.8%) uninterrupted warfarin patients (P = 0.113). No patient developed either other bleeding or thromboembolic events during 7 days after CAG. We demonstrated that an uninterrupted warfarin strategy did not increase vascular access site complications in patients undergoing transfemoral CAG compared to heparin bridging therapy. Due to the safety and the ease of uninterrupted warfarin strategy, this approach should be encouraged in patients receiving long-term warfarin who undergo elective transfemoral CAG. © 2017, Wiley Periodicals, Inc.

Vascular access cannulation in hemodialysis patients - a survey of current practice and its relation to dialysis dose.

PubMed

Gauly, Adelheid; Parisotto, Maria Teresa; Skinder, Aleksandra; Schoder, Volker; Furlan, Andreja; Schuh, Erika; Marcelli, Daniele

2011-01-01

The appropriate use of vascular access is of fundamental importance in the treatment of hemodialysis (HD) patients. This survey entailed collecting data on current practice of vascular access cannulation to assess its relation to dialysis dose. This international, multicenter, observational, cross-sectional survey was performed in 171 dialysis centers of the European dialysis network of Fresenius Medical Care in Europe and South Africa during April 2009. Practice patterns of vascular access cannulations were documented by means of a 24-item questionnaire. Dialysis dose from the documented hemodialysis treatments was derived from the clinical database EuCliD®. In total, 10,807 cannulations in hemodialysis patients with either arteriovenous fistula (91%) or arteriovenous graft (9%) were documented. For the puncture, the area technique was applied most frequently using 15G and 16G needles. Blood flow rates were mostly between 300 and 400 mL/min and adjusted to the needle size used. In two-thirds of cases the arterial needle was placed first, mostly in an antegrade direction, with an average distance to the venous needle of 7.0±3.7 cm. More than two-thirds of the cannulations were performed by nurses with more than 5 years of experience in dialysis. A logistic regression model revealed a significantly higher odds ratio to attain Kt/V = 1.2 for retrograde placement of the arterial needle, and for using needles with bigger diameter. This survey covered a broad number of countries and centers and provides information on current practice of vascular access cannulation, their effect on dialysis dose, and serves as feedback to the dialysis centers for their quality management process.

Use of vascular access for haemodialysis in Europe: a report from the ERA-EDTA Registry.

PubMed

Noordzij, Marlies; Jager, Kitty J; van der Veer, Sabine N; Kramar, Reinhard; Collart, Frederic; Heaf, James G; Stojceva-Taneva, Olivera; Leivestad, Torbjørn; Buturovic-Ponikvar, Jadranka; Benítez Sánchez, Manuel; Moreso, Fransesc; Prütz, Karl G; Severn, Alison; Wanner, Christoph; Vanholder, Raymond; Ravani, Pietro

2014-10-01

Although arteriovenous fistulas (AVFs) are actively promoted, their use at the start of haemodialysis (HD) seems to be decreasing worldwide. In this paper, we describe recent trends in incidence and prevalence of vascular access types in Europe from 2005 to 2009 and their relationship with patient characteristics and survival. Ten European renal registries participating in the ERA-EDTA Registry provided data on incidence (n = 13,044) and/or prevalence (n = 75,715) of vascular access types. We used logistic regression to assess which factors influence the likelihood to be treated with an AVF rather than another type. The use of AVFs at the start of HD showed a significant decreasing trend from 42% in 2005 to 32% in 2009 (P < 0.0001), while the use of central venous catheters (CVCs) increased from 58 to 68% (P < 0.0001). A similar evolution pattern was observed for the prevalence; use of AVFs decreased from 66 to 62% and use of CVCs increased from 28 to 32%. There was a large international variation in the use of the different vascular access types. Female patients [adjusted odds ratio: 0.84, 95% confidence interval (CI): 0.78-0.90] and those ≥80 years (0.77, 95% CI: 0.67-0.90) were least likely to start HD with an AVF. In Europe, there is a decreasing trend in the use of AVFs and an increasing trend in the use of CVCs at the start and after the start of HD. We cannot explain all between-country variations we found, and more research is needed to clarify how healthcare around vascular access is organized in Europe. © The Author 2014. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

A registry-based randomized trial comparing radial and femoral approaches in women undergoing percutaneous coronary intervention: the SAFE-PCI for Women (Study of Access Site for Enhancement of PCI for Women) trial.

PubMed

Rao, Sunil V; Hess, Connie N; Barham, Britt; Aberle, Laura H; Anstrom, Kevin J; Patel, Tejan B; Jorgensen, Jesse P; Mazzaferri, Ernest L; Jolly, Sanjit S; Jacobs, Alice; Newby, L Kristin; Gibson, C Michael; Kong, David F; Mehran, Roxana; Waksman, Ron; Gilchrist, Ian C; McCourt, Brian J; Messenger, John C; Peterson, Eric D; Harrington, Robert A; Krucoff, Mitchell W

2014-08-01

This study sought to determine the effect of radial access on outcomes in women undergoing percutaneous coronary intervention (PCI) using a registry-based randomized trial. Women are at increased risk of bleeding and vascular complications after PCI. The role of radial access in women is unclear. Women undergoing cardiac catheterization or PCI were randomized to radial or femoral arterial access. Data from the CathPCI Registry and trial-specific data were merged into a final study database. The primary efficacy endpoint was Bleeding Academic Research Consortium type 2, 3, or 5 bleeding or vascular complications requiring intervention. The primary feasibility endpoint was access site crossover. The primary analysis cohort was the subgroup undergoing PCI; sensitivity analyses were conducted in the total randomized population. The trial was stopped early for a lower than expected event rate. A total of 1,787 women (691 undergoing PCI) were randomized at 60 sites. There was no significant difference in the primary efficacy endpoint between radial or femoral access among women undergoing PCI (radial 1.2% vs. 2.9% femoral, odds ratio [OR]: 0.39; 95% confidence interval [CI]: 0.12 to 1.27); among women undergoing cardiac catheterization or PCI, radial access significantly reduced bleeding and vascular complications (0.6% vs. 1.7%; OR: 0.32; 95% CI: 0.12 to 0.90). Access site crossover was significantly higher among women assigned to radial access (PCI cohort: 6.1% vs. 1.7%; OR: 3.65; 95% CI: 1.45 to 9.17); total randomized cohort: (6.7% vs. 1.9%; OR: 3.70; 95% CI: 2.14 to 6.40). More women preferred radial access. In this pragmatic trial, which was terminated early, the radial approach did not significantly reduce bleeding or vascular complications in women undergoing PCI. Access site crossover occurred more often in women assigned to radial access. (SAFE-PCI for Women; NCT01406236). Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Vascular Access Type and Patient and Technique Survival in Home Hemodialysis Patients: The Canadian Organ Replacement Register.

PubMed

Perl, Jeffrey; Nessim, Sharon J; Moist, Louise M; Wald, Ron; Na, Yingbo; Tennankore, Karthik K; Chan, Christopher T

2016-02-01

While central venous catheter (CVC) use has expanded home hemodialysis (HHD) eligibility to many patients who may be unable to self-cannulate an arteriovenous (AV) access, the association between CVC use and mortality has not been directly examined among HHD patients. Registry-based retrospective observational cohort study. Incident HHD patients in The Canadian Organ Replacement Register who had information for vascular access type (CVC vs AV access) within the first year of HHD therapy initiation. Use of a CVC versus an AV access (AV fistula or graft) within the first year of HHD therapy initiation. The composite of all-cause mortality and technique failure (long-term transfer to an alternate dialysis modality). A Cox proportional hazards model was used to evaluate the adjusted composite outcome and each outcome separately. 1,869 patients initiated HHD therapy in Canada in 1996 to 2012, of whom 1,217 had an access type recorded within the first year of HHD therapy initiation. Compared to CVC use (n=523) and during a median follow-up of 513 and 427 days for AV access and CVC patients, respectively, AV access use (n=694) was associated with lower risk for the composite event of death and technique failure (490 events; adjusted HR, 0.78; 95% CI, 0.64-0.94) and lower adjusted all-cause mortality (129 deaths; adjusted HR, 0.63; 95% CI, 0.43-0.91); the risk for technique failure was nominally lower, but this result was not statistically significant (361 events; adjusted HR, 0.84; 95% CI, 0.67-1.05). Results were robust to sensitivity analyses and after missing data imputation. Missing information for vascular access type (n=659[35% of patients]) and lack of information for longitudinal changes in vascular access type. Compared to CVC use, AV access use was associated with superior survival. Minimizing CVC use and maximizing AV access use while addressing barriers to their placement and self-cannulation may improve HHD outcomes. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Cost-effectiveness Analysis of Vascular Access Referral Policies in CKD.

PubMed

Shechter, Steven M; Chandler, Talon; Skandari, M Reza; Zalunardo, Nadia

2017-09-01

The optimal timing of vascular access referral for patients with chronic kidney disease who may need hemodialysis (HD) is a pressing question in nephrology. Current referral policies have not been rigorously compared with respect to costs and benefits and do not consider patient-specific factors such as age. Monte Carlo simulation model. Patients with chronic kidney disease, referred to a multidisciplinary kidney clinic in a universal health care system. Cost-effectiveness analysis, payer perspective, lifetime horizon. The following vascular access referral policies are considered: central venous catheter (CVC) only, arteriovenous fistula (AVF) or graft (AVG) referral upon HD initiation, AVF (or AVG) referral when HD is forecast to begin within 12 (or 3 for AVG) months, AVF (or AVG) referral when estimated glomerular filtration rate is <15 (or <10 for AVG) mL/min/1.73m 2 . Incremental cost-effectiveness ratios (ICERs, in 2014 US dollars per quality-adjusted life-year [QALY] gained). The ICER of AVF (AVG) referral within 12 (3) months of forecasted HD initiation, compared to using only a CVC, is ∼$105k/QALY ($101k/QALY) at a population level (HD costs included). Pre-HD AVF or AVG referral dominates delaying referral until HD initiation. The ICER of pre-HD referral increases with patient age. Results are most sensitive to erythropoietin costs, ongoing HD costs, and patients' utilities for HD. When ongoing HD costs are excluded from the analysis, pre-HD AVF dominates both pre-HD AVG and CVC-only policies. Literature-based estimates for HD, AVF, and AVG utilities are limited. The cost-effectiveness of vascular access referral is largely driven by the annual costs of HD, erythropoietin costs, and access-specific utilities. Further research is needed in the field of dialysis-related quality of life to inform decision making regarding vascular access referral. Copyright © 2017 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Quality of vascular surgery Web sites on the Internet.

PubMed

Grewal, Perbinder; Williams, Bryn; Alagaratnam, Swethan; Neffendorf, James; Soobrah, Ritish

2012-11-01

This study evaluated the readability, accessibility, usability, and reliability of vascular surgery information on the Internet in the English language. The Google, Yahoo, and MSN/Bing search engines were searched for "carotid endarterectomy," "EVAR or endovascular aneurysm repair," and "varicose veins or varicose veins surgery." The first 50 Web sites from each search engine for each topic were analyzed. The Flesch Reading Ease Score and Gunning Fog Index were calculated to assess readability. The LIDA tool (Minervation Ltd, Oxford, UK) was used to assess accessibility, usability, and reliability. The Web sites were difficult to read and comprehend. The mean Flesch Reading Ease scores were 53.53 for carotid endarterectomy, 50.53 for endovascular aneurysm repair, and 58.59 for varicose veins. The mean Gunning Fog Index scores were 12.3 for carotid endarterectomy, 12.12 for endovascular aneurysm repair, and 10.69 for varicose veins. The LIDA values for accessibility were good, but the results for usability and reliability were poor. Internet information on vascular surgical conditions and procedures is poorly written and unreliable. We suggest that health professionals should recommend Web sites that are easy to read and contain high-quality surgical information. Medical information on the Internet must be readable, accessible, usable, and reliable. Copyright © 2012 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Clinical analysis and classification of dark eye circle.

PubMed

Huang, Yau-Li; Chang, Shyue-Luen; Ma, Lih; Lee, Mei-Ching; Hu, Sindy

2014-02-01

Dark eye circle (DEC) is a common problem that usually lacks detailed classification in the etiology and structural variations. A newly-developed DEC Assessment Score using Wood's lamp and ultrasonogram will provide a more precise evaluation of DEC for improving treatment results. Sixty-five cases, including eight males and 57 females with a mean age of 38.9 years, were enrolled. DEC were classified into pigmented (brown), vascular (blue to purple), structural, and mixed type by Wood's lamp and ultrasonogram. A scoring system with nine parameters, including brown hue, pigmented lesions, blue/pink/purple hue, periorbital puffiness, shadow hue, infraorbital palpebral bags, infraorbital grooves, blepharoptosis, and skin type, was used for clinical evaluation. Pigmented, vascular, structural, and mixed types of DEC represented 5%, 14%, 3%, and 78%, respectively. Thirty-three cases with periorbital puffiness were found to have higher "pre-septal thickness" than those of 20 controlled cases (P = 0.032). Fourteen patients with infraorbital palpebral bags were proved to have protruded retroseptal fat pads by ultrasonography. Pigmentation and vascular and structural components may play important roles in DEC. Detailed classification of DEC types will access physicians in the decision of appropriate therapeutic modalities. © 2013 The International Society of Dermatology.

Using the Vessel Health and Preservation framework to enhance vein assessment and vascular access device selection.

PubMed

Shaw, Sally Jane

2017-07-12

There is a range of risk factors that can lead to peripheral intravenous (IV) cannula failure, and several failed cannulation attempts can result in the patient experiencing increased pain, discomfort and delays in receiving IV therapy. The Vessel Health and Preservation (VHP) framework is a tool that can be used to improve clinical decision-making and the patient experience in relation to vascular access and IV therapy. Use of the VHP framework can ensure the right vein and right vascular access device (VAD) is selected at the right time for each patient. This article describes how healthcare practitioners can use the VHP framework to support and enhance vein assessment and VAD selection. It outlines the various types of VAD available, focusing on short-term peripheral IV cannulae, which are the most commonly used devices. It also explores the potential benefits of implementing the VHP framework in clinical areas.

Vascular nursing experience, practice knowledge, and beliefs: Results from the Michigan PICC1 survey.

PubMed

Chopra, Vineet; Kuhn, Latoya; Ratz, David; Flanders, Scott A; Krein, Sarah L

2016-04-01

Peripherally inserted central catheters (PICCs) are increasingly used in hospitalized patients. Yet, little is known about the vascular access nurses who often place them. We conducted a Web-based survey to assess vascular access nursing experience, practice, knowledge, and beliefs related to PICC insertion and care in 47 Michigan hospitals. The response rate was 81% (172 received invitations, 140 completed the survey). More than half of all respondents (58%) reported placing PICCs for ≥5 years, and 23% had obtained dedicated vascular access certification. The most common reported indications for PICC insertion included intravenous antibiotics, difficult venous access, and chemotherapy. Many respondents (46%) reported placing a PICC in a patient receiving dialysis; however, 91% of these respondents reported receiving approval from nephrology prior to insertion. Almost all respondents (91%) used ultrasound to find a suitable vein for PICC insertion, and 76% used electrocardiography guidance to place PICCs. PICC occlusion was reported as the most frequently encountered complication, followed by device migration and deep vein thrombosis. Although 94% of respondents noted that their hospitals tracked the number of PICCs placed, only 40% reported tracking duration of PICC use. Relatedly, 30% of nurses reported that their hospitals had a written policy to evaluate PICC necessity or appropriateness. This survey of vascular nursing experiences highlights opportunities to improve practices such as avoiding PICC use in dialysis, better tracking of PICC dwell times, and necessity. Hospitalists may use these data to inform clinical practice, appropriateness, and safety of PICCs in hospitalized patients. © 2015 Society of Hospital Medicine.

Hemodialysis Arteriovenous Vascular Access Creation After Kidney Transplant Failure.

PubMed

Zhang, Joyce C; Al-Jaishi, Ahmed; Perl, Jeffery; Garg, Amit X; Moist, Louise M

2015-10-01

Little is known about vascular access in patients starting hemodialysis therapy after kidney transplant failure. Retrospective cohort study. Adult patients (aged ≥18 years) who started hemodialysis therapy in Ontario, Canada, from January 1, 2001, through December 31, 2010, after kidney transplant failure. Patient clinical and demographic characteristics. Proportion and timing of arteriovenous (AV) vascular access creation (fistula or graft) 12 months prior and up to 24 months after starting hemodialysis therapy. Event rates and outcome predictors. Our cohort included 683 patients with a mean age of 48 years and >50% with comorbidity index score < 3. In the 12 months predialysis and 24 months postdialysis, 16% and 47% of patients had an AV access created, respectively. In the postdialysis period, 13%, 26%, and 38% of patients had an AV access creation at 3, 6, and 12 months, respectively. History of coronary artery disease, diabetes mellitus, and peritoneal dialysis use prior to transplantation were associated with a lower likelihood of AV access creation. Residual selection bias from unmeasured variables beyond the data elements. In Ontario, AV access creation, both before and after starting hemodialysis therapy, is low in patients with kidney transplant failure despite their being younger and healthier compared to the overall hemodialysis population. This highlights the need for a predialysis care pathway in the transplantation clinic and an active strategy to identify this patient cohort receiving hemodialysis to align modality and access choices. Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Early cannulation prosthetic graft (Acuseal) for arteriovenous access: a useful option to provide a personal vascular access solution.

PubMed

Aitken, Emma L; Jackson, Andrew J; Kingsmore, David B

2014-01-01

Early cannulation arteriovenous grafts (ecAVGs), such as the GORE Acuseal, have "low bleed" properties permitting cannulation within 24 hours of insertion. They may provide an alternative to tunneled central venous catheters (and associated line complications) in patients requiring urgent vascular access. We present our early experience of 37 patients treated with the GORE Acuseal ecAVG. A total of 11 upper limb, 24 lower limb and 2 complex graft procedures were performed. Indications for ecAVG were as follows: bridge to transplantation (21.6%); bridge to arteriovenous fistula (AVF) maturation (8.1%); AVF salvage (8.1%); no native options (67.6%, including 17 patients with bilateral central vein stenosis); 36 AVGs (97.3%) were successfully cannulated. Mean time to first cannulation: 30.4±23.4 hours (range: 2-192). Primary and secondary patency rates at 3, 6 and 12 months were 64.9%, 48.6%, 32.4% and 70.2%, 59.4%, 40.5% respectively. The systemic bacteremia rate was 0.2 per 1,000 access days. There was one perioperative death. Other complications included hematoma at cannulation sites (n=9), pseudoaneurysm (n=3) and local infection at graft site (n=6). A total of 26 of 37 patients (70.6%) achieved a "personal vascular access solution": bridge to transplantation (n=8), bridge to functioning AVF/interposition AVG (n=5), maintenance hemodialysis via ecAVG (n=13); death with functioning AVG (n=1). Early experience with the GORE Acuseal is encouraging. Patency and bacteremia rates are at least comparable to standard polytetrafluoroethylene grafts. ecAVGs have permitted cannulation within 24 hours of insertion and line avoidance in the majority of patients. Nearly three-quarters of patients achieved a definitive "personal vascular access solution" from their ecAVG.

Simultaneous Iliac Vein Bovine Pericardial Patch Venoplasty and Creation of PTFE Lower Limb Arteriovenous Fistula Graft for Rescue Vascular Access.

PubMed

Meecham, Lewis; Fisher, Owain; Kirby, George; Evans, Richard; Buxton, Pauline; Legge, Jocelyn; Rajagopalan, Sriram; Asquith, John; Pherwani, Arun

2016-10-01

We present a case of external iliac vein patch venoplasty to accommodate rescue vascular access via a polytetrafluoroethylene loop arteriovenous fistula graft (AVG) for a patient with multiple central venous stenoses. A 35-year-old female with anti-glomerular basement membrane antibody disease required rescue vascular access for hemodialysis. Repeated occlusion and/or thrombosis of long-term central venous access cannulae, to facilitate dialysis, had caused stenosis of brachiocephalic veins: right external iliac vein and occlusion of the left common iliac vein. A previous right brachiobasilic fistula had occluded within 1 year. No other upper limb options for arteriovenous fistula (AVF) were available. A right external iliac vein bovine patch angioplasty concurrently with a polytetrafluoroethylene AV graft between common femoral artery and common femoral vein was performed to restore venous patency and allow rescue dialysis access. At 3-year follow-up, the fistula remains widely patent with 2 L/min flow rates and no recurrent stenosis to the treated iliac vein. She has not required any further surgical or interventional radiological procedures to maintain fistula or central venous patency. Central venous stenosis or occlusion is common for patients requiring dialysis, especially those with multiple previous long-term central venous cannulations. If restriction of outflow is present, AVF may fail. Venous patch angioplasty in these cases is a successful technique, allowing AVF formation and long-term patency. Central venous stenosis can be treated successfully with patch venoplasty to accommodate AVF/AVG formation for rescue vascular access; this is a potentially lifesaving intervention for patients requiring dialysis. Copyright © 2016 Elsevier Inc. All rights reserved.

Infection and hemodialysis access: an updated review.

PubMed

Gupta, Vineet; Yassin, Mohamed H

2013-06-01

The incidence of end-stage renal disease (ESRD) has almost doubled over past 2 decades. Despite decreasing overall hospital admission rates for ESRD population, the rate of infection-related hospitalizations has steadily increased. Infection remains the second most common cause of mortality in this patient population. Specifically, in the hemodialysis (HD) patients, the vascular access related infections are the most common identifiable source of infection. This concise review provides an update on the bacteremia related to vascular access primarily the catheters (Catheter Related Blood Stream Infection- CRBSI) in HD patients emphasizing on the determinants ranging from the epidemiology to pathogenesis, risk factors, cost implications and prevention. Staphylococcus aureus, coagulase negative Staphylococci, and Enterococci are the most common causative microorganisms implicated in CRBSI. The pathogenesis of CRBSI includes organism entry into the blood stream followed by adherence to catheter, colonization and biofilm formation. Vascular access type, catheter position, and prior bacteremic episodes are strongly associated with blood stream infection. Preventive measures should be multidisciplinary in nature and should include avoidance of central venous catheters, best practices for catheter care, surveillance, antimicrobial catheter lock solutions, and use of antibiotic impregnated catheters.

Substantial harm associated with failure of chronic paediatric central venous access devices.

PubMed

Ullman, Amanda J; Kleidon, Tricia; Cooke, Marie; Rickard, Claire M

2017-07-06

Central venous access devices (CVADs) form an important component of modern paediatric healthcare, especially for children with chronic health conditions such as cancer or gastrointestinal disorders. However device failure and complications rates are high.Over 2½ years, a child requiring parenteral nutrition and associated vascular access dependency due to 'short gut syndrome' (intestinal failure secondary to gastroschisis and resultant significant bowel resection) had ten CVADs inserted, with ninesubsequently failing. This resulted in multiple anaesthetics, invasive procedures, injuries, vascular depletion, interrupted nutrition, delayed treatment and substantial healthcare costs. A conservative estimate of the institutional costs for each insertion, or rewiring, of her tunnelled CVAD was $A10 253 (2016 Australian dollars).These complications and device failures had significant negative impact on the child and her family. Considering the commonality of conditions requiring prolonged vascular access, these failures also have a significant impact on international health service costs. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Closed-Loop Resuscitation of Hemorrhagic Shock: Novel Solutions Infused to Hypotensive and Normotensive Endpoints

DTIC Science & Technology

2007-06-29

Anesthesia & Analgesia 98(4S):SCA 85, 2004. 5. Kramer GC, Brown TLH, Michell MW, Oliveira H, Herndon DN, Muller M, Baker RD: Enteral Resuscitation...Honolulu, Hawaii; Anesth Analg 98(4S):SCA 85, 2004. 10. Bruttig, SPGC, Kramer, GC: Clinical record of emergency vascular access using adult intraosseous ...supplement 1): abstracts 49, 2007. NATO Reports: 1. Bruttig SP, Kramer GC: Clinical record of emergency vascular access using adult intraosseous (10

Percutaneous transfacial direct embolization of an intraosseous dural arteriovenous fistula.

PubMed

Nerva, John D; Hallam, Danial K; Ghodke, Basavaraj V

2014-03-01

An intraosseous dural arteriovenous fistula (DAVF) is a rare cerebrovascular disease. The fistulous connection occurs within intraosseous diploic or transosseous emissary veins causing dilated intraosseous vascular pouches. To the authors' knowledge, this report describes the first percutaneous transfacial direct embolization of an intraosseous DAVF. A man in his 50s with blue rubber bleb nevus syndrome presented with headaches, imbalance, decreased visual acuity bilaterally, and left eye proptosis and chemosis. Imaging demonstrated an extensive intraosseous DAVF with dilated intraosseous vascular pouches throughout his cranial base and intraorbital venous congestion. He underwent staged endovascular treatment with the goal to improve his ocular symptoms. Transarterial and transvenous approaches failed to provide adequate access to the intraosseous vascular pouches. A direct, percutaneous transfacial approach was used to access the pouches for embolization with coils and liquid embolic material. Postoperative angiography demonstrated successful embolization of the pouch within the left pterygoid wing, reduced opacification of the intraosseous fistula, and elimination of intraorbital venous congestion. At 9-month follow-up, the patient's headaches had resolved, and his ocular symptomatology had improved. Endovascular access to an intraosseous DAVF is limited by the size and location of the intraosseous vascular pouches. In this case, a direct transfacial approach under image guidance facilitated access and embolization, which led to an improvement in the patient's symptoms. This technique is a novel approach for DAVF management.

Initial experience with the Cardiva Boomerang vascular closure device in diagnostic catheterization.

PubMed

Doyle, Brendan J; Godfrey, Michael J; Lennon, Ryan J; Ryan, James L; Bresnahan, John F; Rihal, Charanjit S; Ting, Henry H

2007-02-01

The authors studied the safety and efficacy of the Cardiva Boomerang vascular closure device in patients undergoing diagnostic cardiac catheterization. Conventional vascular closure devices (sutures, collagen plugs, or metal clips) have been associated with catastrophic complications including arterial occlusion and foreign body infections; furthermore, they cannot be utilized in patients with peripheral vascular disease or vascular access site in a vessel other than the common femoral artery. The Cardiva Boomerang device facilitates vascular hemostasis without leaving any foreign body behind at the access site, can be used in peripheral vascular disease, and can be used in vessels other than the common femoral artery A total of 96 patients undergoing transfemoral diagnostic cardiac catheterization were included in this study, including 25 (26%) patients with contraindications to conventional closure devices. Femoral angiography was performed prior to deployment of the Cardiva Boomerang closure device. Patients were ambulated at 1 hr after hemostasis was achieved. The device was successfully deployed and hemostasis achieved with the device alone in 95 (99%) patients. The device failed to deploy in 1 (1%) patient and required conversion to standard manual compression. Minor complications were observed in 5 (5%) patients. No patients experienced major complications including femoral hematoma > 4 cm, red blood cell transfusion, retroperitoneal bleed, arteriovenous fistula, pseudoaneurysm, infection, arterial occlusion, or vascular surgery. The Cardiva Boomerang device is safe and effective in patients undergoing diagnostic cardiac catheterization using the transfemoral approach, facilitating early ambulation with low rates of vascular complications. (c) 2006 Wiley-Liss, Inc.

Teaching medical students ultrasound-guided vascular access - which learning method is best?

PubMed

Lian, Alwin; Rippey, James C R; Carr, Peter J

2017-05-15

Ultrasound is recommended to guide insertion of peripheral intravenous vascular cannulae (PIVC) where difficulty is experienced. Ultrasound machines are now common-place and junior doctors are often expected to be able to use them. The educational standards for this skill are highly varied, ranging from no education, to self-guided internet-based education, to formal, face-to-face traditional education. In an attempt to decide which educational technique our institution should introduce, a small pilot trial comparing educational techniques was designed. Thirty medical students were enrolled and allocated to one of three groups. PIVC placing ability was then observed, tested and graded on vascular access phantoms. The formal, face-to-face traditional education was rated best by the students, and had the highest success rate in PIVC placement, the improvement statistically significant compared to no education (p = 0.01) and trending towards significance when compared to self-directed internet-based education (p<0.06). The group receiving traditional face-to-face teaching on ultrasound-guided vascular access, performed significantly better than those not receiving education. As the number of ultrasound machines in clinical areas increases, it is important that education programs to support their safe and appropriate use are developed.

CIRSE Vascular Closure Device Registry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reekers, Jim A., E-mail: j.a.reekers@amc.uva.nl; Mueller-Huelsbeck, Stefan; Libicher, Martin

2011-02-15

Purpose: Vascular closure devices are routinely used after many vascular interventional radiology procedures. However, there have been no major multicenter studies to assess the safety and effectiveness of the routine use of closure devices in interventional radiology. Methods: The CIRSE registry of closure devices with an anchor and a plug started in January 2009 and ended in August 2009. A total of 1,107 patients were included in the registry. Results: Deployment success was 97.2%. Deployment failure specified to access type was 8.8% [95% confidence interval (95% CI) 5.0-14.5] for antegrade access and 1.8% (95% CI 1.1-2.9) for retrograde access (Pmore » = 0.001). There was no difference in deployment failure related to local PVD at the access site. Calcification was a reason for deployment failure in only <0.5% of patients. Postdeployment bleeding occurred in 6.4%, and most these (51.5%) could be managed with light manual compression. During follow-up, other device-related complications were reported in 1.3%: seven false aneurysms, three hematoma >5.9 cm, and two vessel occlusions. Conclusion: The conclusion of this registry of closure devices with an anchor and a plug is that the use of this device in interventional radiology procedures is safe, with a low incidence of serious access site complications. There seems to be no difference in complications between antegrade and retrograde access and other parameters.« less

Patients undergoing PCI from the femoral route by default radial operators are at high risk of vascular access-site complications.

PubMed

Rafie, Ihsan M; Uddin, Muez M; Ossei-Gerning, Nicholas; Anderson, Richard A; Kinnaird, Timothy D

2014-02-01

Radial artery (RA) access for PCI has a lower incidence of vascular access-site (VAS) complications than the femoral artery (FA) approach. However, even for default radial operators certain patients are intervened upon from the FA. We examined the demographics and incidence of VAS complications when default radial operators resort to the FA for PCI. The demographics and VAS complications were compared by access site retrospectively for all PCI cases performed by default radial operators (n=1,392). A modified ACUITY trial definition of major VAS complication was used. FA puncture occurred in 25.2% (351/1,392) of cases. Patients were more likely to be female, older and weigh less than patients undergoing PCI from the RA. The FA procedure was likely to be more complex with larger sheaths, more left main stem, graft and multivessel intervention, and there was a greater proportion of emergency cases. Despite increased case complexity, glycoprotein inhibitors were used less frequently in femoral cases (26.5% vs. 36.8%, p<0.001). A VAS complication occurred in 12.5% (44/351) of cases. The risk factors for access-site bleeding are disproportionately high in the population requiring FA puncture by default radial operators, and as a result such patients have a high rate of vascular access-site complications.

Vascular access for home haemodialysis.

PubMed

Al Shakarchi, Julien; Day, C; Inston, N

2018-03-01

Home haemodialysis has been advocated due to improved quality of life. However, there are very little data on the optimum vascular access for it. A retrospective cohort study was carried on all patients who initiated home haemodialysis between 2011 and 2016 at a large university hospital. Access-related hospital admissions and interventions were used as primary outcome measures. Our cohort consisted of 74 patients. On initiation of home haemodialysis, 62 individuals were using an arteriovenous fistula as vascular access, while the remaining were on a tunnelled dialysis catheter. Of the 12 patients who started on a tunnelled dialysis catheter, 5 were subsequently converted to either an arteriovenous fistula ( n = 4) or an arteriovenous graft ( n = 1). During the period of home haemodialysis use, four arteriovenous fistula failed or thrombosed with patients continuing on home haemodialysis using an arteriovenous graft ( n = 3) or a tunnelled dialysis catheter ( n = 1). To maintain uninterrupted home haemodialysis, interventional rates were 0.32 per arteriovenous fistula/arteriovenous graft access-year and 0.4 per tunnelled dialysis catheter access-year. Hospital admission rates for patients on home haemodialysis were 0.33 per patient-year. Our study has shown that home haemodialysis can be safely and independently performed at home within a closely managed home haemodialysis programme. The authors also advocate the use of arteriovenous fistulas for this cohort of patients due to both low complication and intervention rates.

CIRSE Vascular Closure Device Registry

PubMed Central

Müller-Hülsbeck, Stefan; Libicher, Martin; Atar, Eli; Trentmann, Jens; Goffette, Pierre; Borggrefe, Jan; Zeleňák, Kamil; Hooijboer, Pieter; Belli, Anna-Maria

2010-01-01

Purpose Vascular closure devices are routinely used after many vascular interventional radiology procedures. However, there have been no major multicenter studies to assess the safety and effectiveness of the routine use of closure devices in interventional radiology. Methods The CIRSE registry of closure devices with an anchor and a plug started in January 2009 and ended in August 2009. A total of 1,107 patients were included in the registry. Results Deployment success was 97.2%. Deployment failure specified to access type was 8.8% [95% confidence interval (95% CI) 5.0–14.5] for antegrade access and 1.8% (95% CI 1.1–2.9) for retrograde access (P = 0.001). There was no difference in deployment failure related to local PVD at the access site. Calcification was a reason for deployment failure in only <0.5% of patients. Postdeployment bleeding occurred in 6.4%, and most these (51.5%) could be managed with light manual compression. During follow-up, other device-related complications were reported in 1.3%: seven false aneurysms, three hematoma >5.9 cm, and two vessel occlusions. Conclusion The conclusion of this registry of closure devices with an anchor and a plug is that the use of this device in interventional radiology procedures is safe, with a low incidence of serious access site complications. There seems to be no difference in complications between antegrade and retrograde access and other parameters. PMID:20981425

Vascular ring

MedlinePlus

... with aberrant subclavian and left ligamentum ateriosus; Congenital heart defect - vascular ring; Birth defect heart - vascular ring ... accounts for less than 1% of all congenital heart problems. The condition occurs as often in males ...

[An analysis of the work of vascular service in Smolensk from 2009 to 2014].

PubMed

Triasunova, М A; Agafonov, K I; Nehaeva, K A; Miloserdov, M A; Maslova, N N; Rakov, A M; Agulina, N A

2015-01-01

Report of the regional vascular service center of Smolensk work and work of vascular service of Smolensk region were analyzed. The aim of the study is to analyze work of the vascular service in Smolensk and Smolensk region in 2009-2014. Mortality and morbidity in patients with cardio-vascular diseases in Smolensk Region are higher than in other regions of Russia. Recently a number of patients hospitalized to vascular service centers are increased. Infectious complications (pneumonia, bedsores, pyoderma) take lead place in mortality. Nowadays it's very important to solve the problem with prophylaxis of infectious complications in patients with acute ischemic stroke, also to solve problem with rehabilitation in patients with mild and severe motor disorders and disorders of praxis, gnosis. Continuous training of doctors and nurses in regional vascular service centers is needed. It will increase quality of medical service and improve rehabilitation prognosis in patients with ischemic stroke.

Optimization of the convection volume in online post-dilution haemodiafiltration: practical and technical issues

PubMed Central

Chapdelaine, Isabelle; de Roij van Zuijdewijn, Camiel L.M.; Mostovaya, Ira M.; Lévesque, Renée; Davenport, Andrew; Blankestijn, Peter J.; Wanner, Christoph; Nubé, Menso J.; Grooteman, Muriel P.C.

2015-01-01

In post-dilution online haemodiafiltration (ol-HDF), a relationship has been demonstrated between the magnitude of the convection volume and survival. However, to achieve high convection volumes (>22 L per session) detailed notion of its determining factors is highly desirable. This manuscript summarizes practical problems and pitfalls that were encountered during the quest for high convection volumes. Specifically, it addresses issues such as type of vascular access, needles, blood flow rate, recirculation, filtration fraction, anticoagulation and dialysers. Finally, five of the main HDF systems in Europe are briefly described as far as HDF prescription and optimization of the convection volume is concerned. PMID:25815176

75 FR 38532 - Medical Devices; Availability of Safety and Effectiveness Summaries for Premarket Approval...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-02

... LLIAC March 5, FDA-2010-M-0135 Scientific PREMOUNTED STENT SYSTEM 2010 Corp. P090006 Medtronic COMPLETE SE VASCULAR March 17, FDA-2010-M-0158 Vascular STENT SYSTEM 2010 II. Electronic Access Persons with...

The intraosseous have it: A prospective observational study of vascular access success rates in patients in extremis using video review.

PubMed

Chreiman, Kristen M; Dumas, Ryan P; Seamon, Mark J; Kim, Patrick K; Reilly, Patrick M; Kaplan, Lewis J; Christie, Jason D; Holena, Daniel N

2018-04-01

Quick and successful vascular access in injured patients arriving in extremis is crucial to enable early resuscitation and rapid OR transport for definitive repair. We hypothesized that intraosseous (IO) access would be faster and have higher success rates than peripheral intravenous (PIV) or central venous catheters (CVCs). High-definition video recordings of resuscitations for all patients undergoing emergency department thoracotomy from April 2016 to July 2017 were reviewed as part of a quality improvement initiative. Demographics, mechanism of injury, access type, access location, start and stop time, and success of each vascular access attempt were recorded. Times to completion for access types (PIV, IO, CVC) were compared using Kruskal-Wallis test adjusted for multiple comparisons, while categorical outcomes, such as success rates by access type, were compared using χ test or Fisher's exact test. Study patients had a median age of 30 years (interquartile range [IQR], 25-38 years), 92% were male, 92% were African American, and 93% sustained penetrating trauma. A total of 145 access attempts in 38 patients occurred (median, 3.8; SD, 1.4 attempts per patient). There was no difference between duration of PIV and IO attempts (0.63; IQR, 0.35-0.96 vs. 0.39 IQR, 0.13-0.65 minutes, adjusted p = 0.03), but both PIV and IO were faster than CVC attempts (3.2; IQR, 1.72-5.23 minutes; adjusted p < 0.001 for both comparisons). Intraosseous lines had higher success rates than PIVs or CVCs (95% vs. 42% vs. 46%, p < 0.001). Access attempts using IO are as fast as PIV attempts but are more than twice as likely to be successful. Attempts at CVC access in patients in extremis have high rates of failure and take a median of over 3 minutes. While IO access may not completely supplant PIVs and CVCs, IO access should be considered as a first-line therapy for trauma patients in extremis. Therapeutic, level III.

Flash pulmonary oedema after relief of haemodialysis graft stenosis.

PubMed

Vélez-Martínez, Mariella; Weinberg, Brent D; Mishkin, Joseph D

2013-08-01

Heart failure (HF) and chronic kidney disease (CKD) are undoubtedly very much interrelated, especially in patients with end-stage renal disease (ESRD) who are dependent on renal replacement therapy. Haemodialysis (HD) is of particular interest in cardiovascular patients due to the creation of a haemodialysis vascular access and the haemodynamic changes associated with it. Adequate HD though is very dependent on a properly functioning vascular access. Unfortunately, these surgical vascular accesses are vulnerable to stenoses and occlusions. Percutaneous endovascular treatment of these stenoses is often performed and has been found to be safe and effective. Despite its frequent use, acute medical complications of this percutaneous procedure have not been well-documented. In this report, we describe a patient who developed flash pulmonary oedema after balloon angioplasty treatment of an arteriovenous graft (AVG) stenosis. Copyright © 2012 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Risk factors associated with surgical site infection and the development of short-term complications in macaques undergoing indwelling vascular access port placement.

PubMed

Graham, M L; Rieke, E F; Wijkstrom, M; Dunning, M; Aasheim, T C; Graczyk, M J; Pilon, K J; Hering, B J

2008-08-01

Risk factors associated with surgical site infection (SSI) and the development of short-term complications in macaques undergoing vascular access port (VAP) placement are evaluated in this study. Records from 80 macaques with VAPs were retrospectively reviewed. Logistic regression was used to identify factors associated with short-term post-operative complications. The primary outcome was SSI, which occurred in 21.6% (52.6% in the first 12 months vs. 13% thereafter) of procedures. SSI was associated with major secondary complications including VAP removal (11.4%), wound dehiscence (5.7%), and mechanical catheter occlusion (5.7%). In multivariate modeling, only surgical program progress was a statistically significant predictor of SSI, while animal compliance had a slightly protective effect. Vascular access ports have a moderate risk of complications, provided the surgical program optimizes best practices. Under complex experimental conditions, VAPs represent an important refinement, both improving animals' overall well-being and environment and reducing stress.

Vascular Access Tracking System: a Web-Based Clinical Tracking Tool for Identifying Catheter Related Blood Stream Infections in Interventional Radiology Placed Central Venous Catheters.

PubMed

Morrison, James; Kaufman, John

2016-12-01

Vascular access is invaluable in the treatment of hospitalized patients. Central venous catheters provide a durable and long-term solution while saving patients from repeated needle sticks for peripheral IVs and blood draws. The initial catheter placement procedure and long-term catheter usage place patients at risk for infection. The goal of this project was to develop a system to track and evaluate central line-associated blood stream infections related to interventional radiology placement of central venous catheters. A customized web-based clinical database was developed via open-source tools to provide a dashboard for data mining and analysis of the catheter placement and infection information. Preliminary results were gathered over a 4-month period confirming the utility of the system. The tools and methodology employed to develop the vascular access tracking system could be easily tailored to other clinical scenarios to assist in quality control and improvement programs.

An evaluation of the availability, accessibility, and quality of online content of vascular surgery training program websites for residency and fellowship applicants.

PubMed

Huang, Bryant Y; Hicks, Taylor D; Haidar, Georges M; Pounds, Lori L; Davies, Mark G

2017-12-01

Vascular surgery residency and fellowship applicants commonly seek information about programs from the Internet. Lack of an effective web presence curtails the ability of programs to attract applicants, and in turn applicants may be unable to ascertain which programs are the best fit for their career aspirations. This study was designed to evaluate the presence, accessibility, comprehensiveness, and quality of vascular surgery training websites (VSTW). A list of accredited vascular surgery training programs (integrated residencies and fellowships) was obtained from four databases for vascular surgery education: the Accreditation Council for Graduate Medical Education, Electronic Residency Application Service, Fellowship and Residency Electronic Interactive Database, and Society for Vascular Surgery. Programs participating in the 2016 National Resident Matching Program were eligible for study inclusion. Accessibility of VSTW was determined by surveying the Accreditation Council for Graduate Medical Education, Electronic Residency Application Service, and Fellowship and Residency Electronic Interactive Database for the total number of programs listed and for the presence or absence of website links. VSTW were analyzed for the availability of recruitment and education content items. The quality of VSTW was determined as a composite of four dimensions: content, design, organization, and user friendliness. Percent agreements and kappa statistics were calculated for inter-rater reliability. Eighty-nine of the 94 fellowship (95%) and 45 of the 48 integrated residencies (94%) programs participating in the 2016 Match had a VSTW. For program recruitment, evaluators found an average of 12 of 32 content items (35.0%) for fellowship programs and an average of 12 of 32 (37%) for integrated residencies. Only 47.1% of fellowship programs (53% integrated residencies) specified the number of positions available for the 2016 Match, 20% (13% integrated residencies) indicated alumni career placement, 34% (38% integrated residencies) supplied interview dates, and merely 17% (18% integrated residencies) detailed the selection process. For program education, fellowship websites provided an average of 5.1 of 15 content items (34.0%), and integrated residency websites provided 5 of 14 items (34%). Of the fellowship programs, 66% (84.4% integrated residencies) provided a rotation schedule, 65% (56% integrated residencies) detailed operative experiences, 38% (38% integrated residencies) posted conference schedules, and just 16% (28.9% integrated residencies) included simulation training. The web presence of vascular surgery training programs lacks sufficient accessibility, content, organization, design, and user friendliness to allow applicants to access information that informs them sufficiently. There are opportunities to more effectively use VSTW for the benefit of training programs and prospective applicants. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Anesthesia through an intraosseous line using an 18-gauge intravenous needle for emergency pediatric surgery.

PubMed

Hamed, Riyadh Khudeir; Hartmans, Sharon; Gausche-Hill, Marianne

2013-09-01

To describe the success and complication rate of intraosseous (IO) access for delivery of anesthesia with the use of an 18-gauge (G) intravenous (IV) needle. Prospective study. Children's Welfare Teaching Hospital, Baghdad, Iraq. 300 critically ill infants and toddlers, age 3 weeks to 16 months, requiring emergency surgery for intra-abdominal or pelvic conditions, in whom peripheral or central access was not obtainable. Patients presented for surgery between 2007 and 2010. In 26 patients, the IO catheter was established when peripheral access was not obtained at the outset of surgery; in 4 patients standard peripheral vascular access failed during the surgical procedure and IO access was obtained. An 18-G IV needle was placed into the proximal tibia and attached to an extension set with a 3-way stopcock to deliver anesthesia. For 26 critically ill children and 4 other children, IV access failed during delivery of anesthesia; vascular access was successfully obtained within minutes in all 30 infants (100%) using the intraosseous route. Ninety percent (27/30) of patients awoke immediately postoperatively in good condition; 10% (3/30) went to the pediatric intensive care unit (PICU) for further care due to their critical preoperative condition. Complications associated with use of the IO route were considered minor (3/30 pts [10%]) and included extravasation of fluid in two cases and cellulitis in one. The IO route provided for rapid delivery of anesthesia, induction, and maintenance in this series of critically ill infants undergoing emergency surgery when other vascular access routes failed. Few complications were noted. Intraosseous access was achieved through a simple technique using an 18-gauge IV needle. © 2013 Elsevier Inc. All rights reserved.

Duration to Establish an Emergency Vascular Access and How to Accelerate It: A Simulation-Based Study Performed in Real-Life Neonatal Resuscitation Rooms.

PubMed

Schwindt, Eva M; Hoffmann, Florian; Deindl, Philipp; Waldhoer, Thomas J; Schwindt, Jens C

2018-05-01

To compare the duration to establish an umbilical venous catheter and an intraosseous access in real hospital delivery rooms and as a secondary aim to assess delaying factors during establishment and to provide recommendations to accelerate vascular access in neonatal resuscitation. Retrospective analysis of audio-video recorded neonatal simulation training. Simulation training events in exact replications of actual delivery/resuscitation rooms of 16 hospitals with different levels of care (Austria and Germany). Equipment was prepared the same way as for real clinical events. Medical teams of four to five persons with birth-related background (midwives, nurses, neonatologists, and anesthesiologists) in a realistic team composition. Audio-video recorded mannequin-based simulated resuscitation of an asphyxiated newborn including the establishment of either umbilical venous catheter or intraosseous access. The duration of access establishment (time from decision to first flush/aspiration), preparation (decision to start of procedure), and the procedure itself (start to first flush/aspiration) was significantly longer for umbilical venous catheter than for intraosseous access (overall duration 199 vs 86 s). Delaying factors for umbilical venous catheter establishment were mainly due to the complex approach itself, the multitude of equipment required, and uncertainties about necessary hygiene standards. Challenges in intraosseous access establishment were handling of the unfamiliar material and absence of an intraosseous access kit in the resuscitation room. There was no significant difference between the required duration for access establishment between large centers and small hospitals, but a trend was observed that duration for umbilical venous catheter was longer in small hospitals than in centers. Duration for intraosseous access was similar in both hospital types. Vascular access establishment in neonatal resuscitation could be accelerated by infrastructural improvements and specific training of medical teams. In simulated in situ neonatal resuscitation, intraosseous access is faster to establish than umbilical venous catheter. Future studies are required to assess efficacy and safety of both approaches in real resuscitation settings.

Intraosseous vascular access in disasters and mass casualty events: A review of the literature.

PubMed

Burgert, James M

2016-01-01

The intraosseous (IO) route of vascular access has been increasingly used to administer resuscitative fluids and drugs to patients in whom reliable intravenous (IV) access could not be rapidly or easily obtained. It is unknown that to what extent the IO route has been used to gain vascular access during disasters and mass casualty events. The purpose of this review was to examine the existing literature to answer the research question, "What is the utility of the IO route compared to other routes for establishing vascular access in patients resulting from disasters and mass casualty events?" Keyword-based online database search of PubMed, CINAHL, and the Cochrane Database of Systematic Reviews. University-based academic research cell. Included evidence were randomized and nonrandomized trials, systematic reviews with and without meta-analysis, case series, and case reports. Excluded evidence included narrative reviews and expert opinion. Not applicable. Of 297 evidence sources located, 22 met inclusion criteria. Located evidence was organized into four categories including chemical agent poisoning, IO placement, while wearing chemical protective clothing (PPE), military trauma, and infectious disease outbreak. Evidence indicates that the IO route of infusion is pharmacokinetically equal to the IV route and superior to the intramuscular (IM) and endotracheal routes for the administration of antidotal drugs in animal models of chemical agent poisoning while wearing full chemical PPE. The IO route is superior to the IM route for antidote administration during hypovolemic shock. Civilian casualties of explosive attacks and mass shootings would likely benefit from expanded use of the IO route and military resuscitation strategies. The IO route is useful for fluid resuscitation in the management of diarrheal and hemorrhagic infectious disease outbreaks.

Non anti-coagulant factors associated with filter life in continuous renal replacement therapy (CRRT): a systematic review and meta-analysis.

PubMed

Brain, Matthew; Winson, Elizabeth; Roodenburg, Owen; McNeil, John

2017-02-20

Optimising filter life and performance efficiency in continuous renal replacement therapy has been a focus of considerable recent research. Larger high quality studies have predominantly focussed on optimal anticoagulation however CRRT is complex and filter life is also affected by vascular access, circuit and management factors. We performed a systematic search of the literature to identify and quantify the effect of vascular access, circuit and patient factors that affect filter life and presented the results as a meta-analysis. A systematic review and meta-analysis was performed by searching Pubmed (MEDLINE) and Ovid EMBASE libraries from inception to 29 th February 2016 for all studies with a comparator or independent variable relating to CRRT circuits and reporting filter life. Included studies documented filter life in hours with a comparator other than anti-coagulation intervention. All studies comparing anticoagulation interventions were searched for regression or hazard models pertaining to other sources of variation in filter life. Eight hundred nineteen abstracts were identified of which 364 were selected for full text analysis. 24 presented data on patient modifiers of circuit life, 14 on vascular access modifiers and 34 on circuit related factors. Risk of bias was high and findings are hypothesis generating. Ranking of vascular access site by filter longevity favours: tunnelled semi-permanent catheters, femoral, internal jugular and subclavian last. There is inconsistency in the difference reported between femoral and jugular catheters. Amongst published literature, modality of CRRT consistently favoured continuous veno-venous haemodiafiltration (CVVHD-F) with an associated 44% lower failure rate compared to CVVH. There was a trend favouring higher blood flow rates. There is insufficient data to determine advantages of haemofilter membranes. Patient factors associated with a statistically significant worsening of filter life included mechanical ventilation, elevated SOFA or LOD score, elevations in ionized calcium, elevated platelet count, red cell transfusion, platelet factor 4 (PF-4) antibodies, and elevated fibrinogen. Majority of studies are observational or report circuit factors in sub-analysis. Risk of bias is high and findings require targeted investigations to confirm. The interaction of patient, pathology, anticoagulation, vascular access, circuit and staff factors contribute to CRRT filter life. There remains an ambiguity from published data as to which site and side should be the first choice for vascular access placement and what interaction this has with patient factors and timing. Early consideration of tunnelled semi-permanent access may provide optimal filter life if longer periods of CRRT are anticipated. There remains an absence of robust evidence outside of anti-coagulation strategies despite over 20 years of therapy delivery however trends favour CVVHD-F over CVVH.

Impact of an Interactive Vascular Surgery Web-Based Educational Curriculum on Surgical Trainee Knowledge and Interest.

PubMed

Zayed, Mohamed A; Lilo, Emily A; Lee, Jason T

The surgical council on resident education developed an online competency-based self-study curriculum for general surgery residency trainees. Vascular surgery trainees are yet to have a similarly validated and readily accessible self-study curriculum. We sought to determine the effect of an interactive online vascular surgery curriculum on trainee knowledge and interest in vascular surgery. Over 15 months, 53 trainees (36 medical students and 16 surgical residents) performing a vascular surgery rotation were enrolled in a prospective, randomized, 2-cohort study. Before starting a 4-week rotation, trainee baseline demographics were collected, and a pretest was administered to evaluate baseline vascular surgery knowledge. During the same study period, 31 trainees (GROUP 1) were randomized to an interactive online curriculum with weekly reading assignments, and 21 trainees (GROUP 2) did not have access to the online curriculum. At the conclusion, all trainees received a posttest and survey to evaluate any change in vascular surgery knowledge and interest. Although 26.8% of trainees predicted that online computer modules would be a beneficial learning tool, most of trainees indicated textbook reading and case discussions are preferred. Analysis of GROUPS 1 and 2 revealed no significant differences in the average trainee age, training level, sex, or number of surgical cases observed during the rotation. Improvement in vascular surgery knowledge in GROUP 1 was significantly higher compared to GROUP 2 (average increase in posttest scores of 16.1% vs 6.6%, p = 0.009). New interest in vascular surgery was increased by 22.2% in GROUP 1, but was decreased by 40% in GROUP 2 (p < 0.001). Basic vascular surgery principles can be efficiently introduced through an interactive online curriculum. This type of self-study can improve trainee knowledge, and foster interest in vascular surgery. As in other specialties, a standardized and validated online vascular surgery curriculum should be developed for emerging trainees. Published by Elsevier Inc.

Feasibility of Human Skin Grafts on an Isolated but Accessible Vascular Supply on Athymic Rats as a System to Study Percutaneous Penetration and Cutaneous Injury.

DTIC Science & Technology

1983-11-01

HUMAN SKIN GRAFTS ON AN ISOLATED BUT ACCESSIBLE VASCULAR SUPPLY ON ATHYMIC RATS AS A SYSTEM TO STUDY PERCUTANEOUS PENETRATION AND CUTANEOUS INJURY...RECIPIENT’S CATALOG NUMBER 4. TITLE (aend Subtitle) S. TYPE OF REPORT & PERIOD COVERED Feasibility of Human Skin Grafts on an Isolated Annual report...Human skin graft on athymic rat Human skin model to study percutaneous penetration and cutaneous injury 20. ABSTRACT (Contiue an reverse *ftb it

Embedding a randomized clinical trial into an ongoing registry infrastructure: unique opportunities for efficiency in design of the Study of Access site For Enhancement of Percutaneous Coronary Intervention for Women (SAFE-PCI for Women).

PubMed

Hess, Connie N; Rao, Sunil V; Kong, David F; Aberle, Laura H; Anstrom, Kevin J; Gibson, C Michael; Gilchrist, Ian C; Jacobs, Alice K; Jolly, Sanjit S; Mehran, Roxana; Messenger, John C; Newby, L Kristin; Waksman, Ron; Krucoff, Mitchell W

2013-09-01

Women are at higher risk than men for bleeding and vascular complications after percutaneous coronary intervention (PCI). Compared with femoral access, radial access reduces these complications but may be more challenging in women because of higher rates of radial artery spasm, tortuosity, and occlusion as well as lower rates of procedure success. Whether the safety advantages of radial versus femoral access in women undergoing PCI are outweighed by reduced effectiveness has not been studied. The Study of Access site For Enhancement of PCI for Women is a prospective, randomized clinical trial comparing radial with femoral arterial access in women undergoing PCI. In conjunction with the US Food and Drug Administration's Critical Path Cardiac Safety Research Consortium, this study embeds the randomized clinical trial into the existing infrastructure of the National Cardiovascular Data Registry CathPCI Registry through the National Institute of Health's National Cardiovascular Research Infrastructure. The primary efficacy end point is a composite of bleeding (Bleeding Academic Research Consortium types 2, 3, or 5) or vascular complication requiring intervention occurring at 72 hours after PCI or by hospital discharge. The primary feasibility end point is procedure success. Secondary end points include procedure duration, contrast volume, radiation dose, quality of life, and a composite of 30-day death, vascular complication, or unplanned revascularization. © 2013.

Patient preference for radial versus femoral vascular access for elective coronary procedures: The PREVAS study.

PubMed

Kok, Marlies M; Weernink, Marieke G M; von Birgelen, Clemens; Fens, Anneloes; van der Heijden, Liefke C; van Til, Janine A

2018-01-01

To explore patient preference for vascular access site in percutaneous coronary procedures, the perceived importance of benefits and risks of transradial access (TRA) and transfemoral access (TFA) were assessed. In addition, direct preference for vascular access and preference for shared decision making (SDM) were evaluated. TRA has gained significant ground on TFA during the last decades. Surveys on patient preference have mostly been performed in dedicated TRA trials. In the PREVAS study (Clinicaltrials.gov: NCT02625493) a stated preference elicitation method best-worst scaling (BWS) was used to determine patient preference for six treatment attributes: bleeding, switch of access-site, postprocedural vessel quality, mobilization and comfort, and over-night stay. Based on software-generated treatment scenarios, 142 patients indicated which characteristics they perceived most and least important in treatment choice. Best-minus-Worst scores and attribute importance were calculated. Bleeding risk was considered most important (attribute importance 31.3%), followed by length of hospitalization (22.6%), and mobilization(20.2%). Most patients preferred the approach of their current procedure (85.9%); however, 71.1% of patients with experience with both access routes favored TRA (P < 0.001). Most patients (38.0%) appreciated SDM, balanced between patient and cardiologist. Patients appreciate lower bleeding risk and early ambulation, factors favoring TRA. Previous experience with a single access route has a major impact on preference, while experience with both routes generally resulted in preference for TRA. Most patients prefer balanced SDM. © 2017 The Authors Catheterization and Cardiovascular Interventions Published by Wiley Periodicals, Inc. © 2017 The Authors Catheterization and Cardiovascular Interventions Published by Wiley Periodicals, Inc.

Potential effects of the new Medicare Prospective Payment System on drug prescription in end-stage renal disease care.

PubMed

Winkelmayer, Wolfgang C

2011-01-01

The Centers for Medicaid and Medicare Services have announced a new Prospective Payment System to reimburse the care furnished by dialysis centers to patients with end-stage renal disease (ESRD). As of January 2011, most aspects of the outpatient treatment of patients with ESRD will be included in a single payment. In addition to the items previously included in the Composite Rate, injectable drugs and their oral equivalents will be included in this new capitation payment, as will the laboratory tests required for monitoring maintenance dialysis. As of January 2014, oral-only medications will also be included. Physician payments and payments for inpatient care, as well as for care not directly related to ESRD care will continue to be reimbursed separately. Patterns of medication treatment of ESRD patients will likely be revisited, and one can expect pronounced adjustments. Treatment of anemia will likely shift towards less use of erythropoiesis-stimulating agents and somewhat towards higher use of intravenous iron supplements. Average hemoglobin concentrations will decline. Use of intravenous vitamin D analogues will likely be reduced and substituted with their oral equivalents in many patients. One can also expect a temporary trend towards higher use of calcimetics, since their inclusion in the payment bundle is deferred until 2014. Treatment of problems with vascular access patency and of access infections will likely shift to the inpatient setting, and there may be reluctance to quickly accept recovering patients back to the outpatient setting after vascular access intervention. On aggregate, these changes have the potential to alter patient outcomes, but it is currently unclear how these will be and can be monitored. Copyright © 2011 S. Karger AG, Basel.

Intraosseous Vascular Access through the Anterior Mandible – A Cadaver Model Pilot Study

PubMed Central

Goldschalt, Christin; Doll, Sara; Ihle, Brit; Kirsch, Joachim; Mutzbauer, Till Sebastian

2014-01-01

Background Several insertion sites have been described for intraosseous puncture in cases of emergencies when a conventional vascular access cannot be established. This pilot study has been designed to evaluate the feasibility of the mandibular bone for the use of an intraosseous vascular access in a cadaver model. Methodology/Principal Findings 17 dentistry and 16 medical students participating in a voluntary course received a short introduction into the method and subsequently used the battery powered EZ-IO system with a 15 mm cannula for a puncture of the anterior mandible in 33 cadavers. The time needed to perform each procedure was evaluated. India ink was injected into the accesses and during the anatomy course cadavers were dissected to retrace the success or failure of the puncture. Dental students needed 25.5±18.9(mean±standard deviation)s and medical students 33±20.4 s for the procedure (p = 0.18). Floor of mouth extravasation occurred in both groups in 3 cases. Success rates were 82 and 75% (p = 0.93). Conclusions/Significance Despite floor of mouth extravasation of injected fluid into a mandibular intraosseous access might severely complicate this procedure, the anterior mandible may be helpful as an alternative to other intraosseous and intravenous insertion sites when these are not available in medical emergencies. PMID:25405476

Skin damage associated with intravenous therapy: common problems and strategies for prevention.

PubMed

Thayer, Debra

2012-01-01

Infusion therapy is among the most common health care interventions, with approximately 90% of hospitalized patients receiving vascular access and an estimated 1.3 million home infusion therapies delivered annually. Whereas most individuals complete their therapy uneventfully, others experience alterations in skin integrity, some significant enough to disrupt therapy. There are limited published data on the incidence of skin damage associated with infusion therapy, and the etiology of damage has not been previously described in detail. Wound, ostomy, and continence (WOC) nurses have developed a significant understanding of skin-related problems and effective prevention strategies from over 40 years of experience with ostomy patients--another population in which adhesive wear is a constant and localized, superficial skin damage is common. This article will offer a WOC nursing perspective of skin damage and seek to provide a context for understanding and preventing skin damage in the infusion therapy patient.

The use of vascular access ports for blood collection in feline blood donors

PubMed Central

Aubert, Isabelle; Abrams-Ogg, Anthony C.G.; Sylvestre, Anne M.; Dyson, Doris H.; Allen, Dana G.; Johnstone, Ian B.

2011-01-01

We investigated vascular access ports for feline blood donation. Eight cats were anesthetized for conventional blood collection by jugular venipuncture at the beginning and end of the study. In-between conventional collections, vascular access ports were used for collection with or without sedation every 6 to 8 wk for 6 mo. Ports remained functional except for one catheter breakage, but intermittent occlusions occurred. Systolic blood pressure was lower during conventional collection. Behavioral abnormalities occurred during 3 port collections. Packed red cells prepared from collected blood were stored at 4°C for 25 d and assessed for quality pre- and post-storage. With both collection methods, pH and glucose level declined, and potassium level, lactate dehydrogenase activity and osmotic fragility increased. There were no differences between methods in pre-storage albumin and HCO3− levels, and pre and post-storage hematocrit, lactate dehydrogenase activity, and glucose and potassium levels. Pre-storage pH and pCO2 were higher with conventional collection, and pre- and post-storage osmotic fragility were greater with port collection. One port became infected, but all cultures of packed red cells were negative. Tissue inflammation was evident at port removal. In a second study of conventional collection in 6 cats, use of acepromazine in premedication did not exacerbate hypotension. The use of vascular access ports for feline blood donation is feasible, is associated with less hypotension, and may simplify donation, but red cell quality may decrease, and effects on donors must be considered. PMID:21461192

A combination of low-dose bevacizumab and imatinib enhances vascular normalisation without inducing extracellular matrix deposition.

PubMed

Schiffmann, L M; Brunold, M; Liwschitz, M; Goede, V; Loges, S; Wroblewski, M; Quaas, A; Alakus, H; Stippel, D; Bruns, C J; Hallek, M; Kashkar, H; Hacker, U T; Coutelle, O

2017-02-28

Vascular endothelial growth factor (VEGF)-targeting drugs normalise the tumour vasculature and improve access for chemotherapy. However, excessive VEGF inhibition fails to improve clinical outcome, and successive treatment cycles lead to incremental extracellular matrix (ECM) deposition, which limits perfusion and drug delivery. We show here, that low-dose VEGF inhibition augmented with PDGF-R inhibition leads to superior vascular normalisation without incremental ECM deposition thus maintaining access for therapy. Collagen IV expression was analysed in response to VEGF inhibition in liver metastasis of colorectal cancer (CRC) patients, in syngeneic (Panc02) and xenograft tumours of human colorectal cancer cells (LS174T). The xenograft tumours were treated with low (0.5 mg kg -1 body weight) or high (5 mg kg -1 body weight) doses of the anti-VEGF antibody bevacizumab with or without the tyrosine kinase inhibitor imatinib. Changes in tumour growth, and vascular parameters, including microvessel density, pericyte coverage, leakiness, hypoxia, perfusion, fraction of vessels with an open lumen, and type IV collagen deposition were compared. ECM deposition was increased after standard VEGF inhibition in patients and tumour models. In contrast, treatment with low-dose bevacizumab and imatinib produced similar growth inhibition without inducing detrimental collagen IV deposition, leading to superior vascular normalisation, reduced leakiness, improved oxygenation, more open vessels that permit perfusion and access for therapy. Low-dose bevacizumab augmented by imatinib selects a mature, highly normalised and well perfused tumour vasculature without inducing incremental ECM deposition that normally limits the effectiveness of VEGF targeting drugs.

Rationale and design of a randomised clinical trial comparing vascular closure device and manual compression to achieve haemostasis after diagnostic coronary angiography: the Instrumental Sealing of ARterial puncture site - CLOSURE device versus manual compression (ISAR-CLOSURE) trial.

PubMed

Xhepa, Erion; Byrne, Robert A; Schulz, Stefanie; Helde, Sandra; Gewalt, Senta; Cassese, Salvatore; Linhardt, Maryam; Ibrahim, Tareq; Mehilli, Julinda; Hoppe, Katharina; Grupp, Katharina; Kufner, Sebastian; Böttiger, Corinna; Hoppmann, Petra; Burgdorf, Christof; Fusaro, Massimiliano; Ott, Ilka; Schneider, Simon; Hengstenberg, Christian; Schunkert, Heribert; Laugwitz, Karl-Ludwig; Kastrati, Adnan

2014-06-01

Vascular closure devices (VCD) have been introduced into clinical practice with the aim of increasing the procedural efficiency and clinical safety of coronary angiography. However, clinical studies comparing VCD and manual compression have yielded mixed results, and large randomised clinical trials comparing the two strategies are missing. Moreover, comparative efficacy studies between different VCD in routine clinical use are lacking. The Instrumental Sealing of ARterial puncture site - CLOSURE device versus manual compression (ISAR-CLOSURE) trial is a prospective, randomised clinical trial designed to compare the outcomes associated with the use of VCD or manual compression to achieve femoral haemostasis. The test hypothesis is that femoral haemostasis after coronary angiography achieved using VCD is not inferior to manual compression in terms of access-site-related vascular complications. Patients undergoing coronary angiography via the common femoral artery will be randomised in a 1:1:1 fashion to receive FemoSeal VCD, EXOSEAL VCD or manual compression. The primary endpoint is the incidence of the composite of arterial access-related complications (haematoma ≥5 cm, pseudoaneurysm, arteriovenous fistula, access-site-related bleeding, acute ipsilateral leg ischaemia, the need for vascular surgical/interventional treatment or documented local infection) at 30 days after randomisation. According to power calculations based on non-inferiority hypothesis testing, enrolment of 4,500 patients is planned. The trial is registered at www.clinicaltrials.gov (study identifier: NCT01389375). The safety of VCD as compared to manual compression in patients undergoing transfemoral coronary angiography remains an issue of clinical equipoise. The aim of the ISAR-CLOSURE trial is to assess whether femoral haemostasis achieved through the use of VCD is non-inferior to manual compression in terms of access-site-related vascular complications.

Trapezius placement of implanted ports: understanding the procedure.

PubMed

Hill, Steve

Totally implantable vascular access devices (TIVADs) are indicated for intermittent long-term intravenous access. It is widely accepted within medical literature that TIVADs are associated with statistically significant lower infection rates than other central venous access devices. Typical sites for implantation are on the anterior chest wall, using the internal jugular, axillary, cephalic or a subclavian vein. This article follows on from a previous discussion of the benefits of this approach, which illustrated and examined clinical outcomes of trapezius-placement versus anterior chest wall placed ports, for patients with metastatic subcutaneous disease on the anterior chest wall. The procedure provides a unique challenge for the clinician. This article focuses on the process of trapezius port implantation, providing an illustrative guide to understand the procedure. Trapezius port placement is a viable option for patients for whom routine sites are excluded and who require long-term intermittent vascular access.

A low cost Doppler system for vascular dialysis access surveillance.

PubMed

Molina, P S C; Moraes, R; Baggio, J F R; Tognon, E A

2004-01-01

The National Kidney Foundation guidelines for vascular access recommend access surveillance to avoid morbidity among patients undergoing hemodialysis. Methods to detect access failure based on CW Doppler system are being proposed to implement surveillance programs at lower cost. This work describes a low cost Doppler system implemented in a PC notebook designed to carry out this task. A Doppler board samples the blood flow velocity and delivers demodulated quadrature Doppler signals. These signals are sampled by a notebook sound card. Software for Windows OS (running at the notebook) applies CFFT to consecutive 11.6 ms intervals of Doppler signals. The sonogram is presented on the screen in real time. The software also calculates the maximum and the intensity weighted mean frequency envelopes. Since similar systems employ DSP boards to process the Doppler signals, cost reduction was achieved. The Doppler board electronic circuits and routines to process the Doppler signals are presented.

Intravascular Neural Interface with Nanowire Electrode

PubMed Central

Watanabe, Hirobumi; Takahashi, Hirokazu; Nakao, Masayuki; Walton, Kerry; Llinás, Rodolfo R.

2010-01-01

Summary A minimally invasive electrical recording and stimulating technique capable of simultaneously monitoring the activity of a significant number (e.g., 103 to 104) of neurons is an absolute prerequisite in developing an effective brain–machine interface. Although there are many excellent methodologies for recording single or multiple neurons, there has been no methodology for accessing large numbers of cells in a behaving experimental animal or human individual. Brain vascular parenchyma is a promising candidate for addressing this problem. It has been proposed [1, 2] that a multitude of nanowire electrodes introduced into the central nervous system through the vascular system to address any brain area may be a possible solution. In this study we implement a design for such microcatheter for ex vivo experiments. Using Wollaston platinum wire, we design a submicron-scale electrode and develop a fabrication method. We then evaluate the mechanical properties of the electrode in a flow when passing through the intricacies of the capillary bed in ex vivo Xenopus laevis experiments. Furthermore, we demonstrate the feasibility of intravascular recording in the spinal cord of Xenopus laevis. PMID:21572940

Systemic Effects of Hemodialysis Access.

PubMed

Agarwal, Anil K

2015-11-01

Patients with advanced chronic kidney disease are at a high risk of cardiovascular events. Patients with end-stage renal disease have a particularly high morbidity and mortality, in part attributed to the complications and dysfunction related to vascular access in this population. Creation of an arteriovenous access for HD is considered standard of care for most patients and has distinct advantages including less likelihood of infections, less need for intervention, and positive impact on survival as compared with usage of a catheter. However, creation of an arteriovenous shunt incites a series of events that significantly impacts cardiovascular and neurohormonal health in both positive and negative ways. This article will review the short- and long-term effects of dialysis access on cardiovascular, neurohormonal, and pulmonary systems as well as a brief review of their effect on survival on HD. Presence of other comorbidities in a patient with dialysis access can amplify these effects, and these considerations are of paramount importance in individualizing the approach to not only the choice of vascular access but also the modality of kidney replacement therapy. Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Transcatheter Amplatzer vascular plug-embolization of a giant postnephrectomy arteriovenous fistula combined with an aneurysm of the renal pedicle by through-and-through, arteriovenous access

PubMed Central

Kayser, Ole; Schäfer, Philipp

2013-01-01

Although endovascular transcatheter embolization of arteriovenous fistulas is minimally invasive, the torrential flow prevailing within a fistula implies the risk of migration of the deployed embolization devices into the downstream venous and pulmonary circulation. We present the endovascular treatment of a giant postnephrectomy arteriovenous fistula between the right renal pedicle and the residual renal vein in a 63-year-old man. The purpose of this case report is to demonstrate that the Amplatzer vascular plug (AVP) can be safely positioned to embolize even relatively large arteriovenous fistulas (AVFs). Secondly, we illustrate that this occluder can even be introduced to the fistula via a transvenous catheter in cases where it is initially not possible to advance the deployment-catheter through a tortuous feeder artery. Migration of the vascular plug was ruled out at follow-up 4 months subsequently to the intervention. Thus, the Amplatzer vascular plug and the arteriovenous through-and-through guide wire access with subsequent transvenous deployment should be considered in similar cases. PMID:23326248

An Auscultaiting Diagnosis Support System for Assessing Hemodialysis Shunt Stenosis by Using Self-organizing Map

NASA Astrophysics Data System (ADS)

Suzuki, Yutaka; Fukasawa, Mizuya; Sakata, Osamu; Kato, Hatsuhiro; Hattori, Asobu; Kato, Takaya

Vascular access for hemodialysis is a lifeline for over 280,000 chronic renal failure patients in Japan. Early detection of stenosis may facilitate long-term use of hemodialysis shunts. Stethoscope auscultation of vascular murmurs has some utility in the assessment of access patency; however, the sensitivity of this diagnostic approach is skill dependent. This study proposes a novel diagnosis support system to detect stenosis by using vascular murmurs. The system is based on a self-organizing map (SOM) and short-time maximum entropy method (STMEM) for data analysis. SOM is an artificial neural network, which is trained using unsupervised learning to produce a feature map that is useful for visualizing the analogous relationship between input data. The author recorded vascular murmurs before and after percutaneous transluminal angioplasty (PTA). The SOM-based classification was consistent with to the classification based on MEM spectral and spectrogram characteristics. The ratio of pre-PTA murmurs in the stenosis category was much higher than the post-PTA murmurs. The results suggest that the proposed method may be an effective tool in the determination of shunt stenosis.

Percutaneous Transsplenic Access to the Portal Vein for Management of Vascular Complication in Patients with Chronic Liver Disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chu, Hee Ho; Kim, Hyo-Cheol, E-mail: angiointervention@gmail.com; Jae, Hwan Jun

Purpose: To evaluate the safety and feasibility of percutaneous transsplenic access to the portal vein for management of vascular complication in patients with chronic liver diseases. Methods: Between Sept 2009 and April 2011, percutaneous transsplenic access to the portal vein was attempted in nine patients with chronic liver disease. Splenic vein puncture was performed under ultrasonographic guidance with a Chiba needle, followed by introduction of a 4 to 9F sheath. Four patients with hematemesis or hematochezia underwent variceal embolization. Another two patients underwent portosystemic shunt embolization in order to improve portal venous blood flow. Portal vein recanalization was attempted inmore » three patients with a transplanted liver. The percutaneous transsplenic access site was closed using coils and glue. Results: Percutaneous transsplenic splenic vein catheterization was performed successfully in all patients. Gastric or jejunal varix embolization with glue and lipiodol mixture was performed successfully in four patients. In two patients with a massive portosystemic shunt, embolization of the shunting vessel with a vascular plug, microcoils, glue, and lipiodol mixture was achieved successfully. Portal vein recanalization was attempted in three patients with a transplanted liver; however, only one patient was treated successfully. Complete closure of the percutaneous transsplenic tract was achieved using coils and glue without bleeding complication in all patients. Conclusion: Percutaneous transsplenic access to the portal vein can be an alternative route for portography and further endovascular management in patients for whom conventional approaches are difficult or impossible.« less

Vascular access for hemodialysis: current perspectives.

PubMed

Santoro, Domenico; Benedetto, Filippo; Mondello, Placido; Pipitò, Narayana; Barillà, David; Spinelli, Francesco; Ricciardi, Carlo Alberto; Cernaro, Valeria; Buemi, Michele

2014-01-01

A well-functioning vascular access (VA) is a mainstay to perform an efficient hemodialysis (HD) procedure. There are three main types of access: native arteriovenous fistula (AVF), arteriovenous graft, and central venous catheter (CVC). AVF, described by Brescia and Cimino, remains the first choice for chronic HD. It is the best access for longevity and has the lowest association with morbidity and mortality, and for this reason AVF use is strongly recommended by guidelines from different countries. Once autogenous options have been exhausted, prosthetic fistulae become the second option of maintenance HD access alternatives. CVCs have become an important adjunct in maintaining patients on HD. The preferable locations for insertion are the internal jugular and femoral veins. The subclavian vein is considered the third choice because of the high risk of thrombosis. Complications associated with CVC insertion range from 5% to 19%. Since an increasing number of patients have implanted pacemakers and defibrillators, usually inserted via the subclavian vein and superior vena cava into the right heart, a careful assessment of risk and benefits should be taken. Infection is responsible for the removal of about 30%-60% of HD CVCs, and hospitalization rates are higher among patients with CVCs than among AVF ones. Proper VA maintenance requires integration of different professionals to create a VA team. This team should include a nephrologist, radiologist, vascular surgeon, infectious disease consultant, and members of the dialysis staff. They should provide their experience in order to give the best options to uremic patients and the best care for their VA.

Skull base tumors: a kaleidoscope of challenge.

PubMed

Khanna, J N; Natrajan, Srivalli; Galinde, Jyotsna

2014-08-01

Resection of skull base lesions has always been riddled with problems like inadequate access, proximity to major vessels, dural tears, cranial nerve damage, and infection. Understanding the modular concept of the facial skeleton has led to the development of transfacial swing osteotomies that facilitates resection in a difficult area with minimal morbidity and excellent cosmetic results. In spite of the current trend toward endonasal endoscopic management of skull base tumors, our series presents nine cases of diverse extensive skull base lesions, 33% of which were recurrent. These cases were approached through different transfacial swing osteotomies through the mandible, a midfacial swing, or a zygomaticotemporal osteotomy as dictated by the three-dimensional spatial location of the lesion, and its extent and proximity to vital structures. Access osteotomies ensured complete removal and good results through the most direct and safe route and good vascular control. This reiterated the fact that transfacial approaches still hold a special place in the management of extensive skull base lesions.

Skull Base Tumors: A Kaleidoscope of Challenge

PubMed Central

Khanna, J.N.; Natrajan, Srivalli; Galinde, Jyotsna

2014-01-01

Resection of skull base lesions has always been riddled with problems like inadequate access, proximity to major vessels, dural tears, cranial nerve damage, and infection. Understanding the modular concept of the facial skeleton has led to the development of transfacial swing osteotomies that facilitates resection in a difficult area with minimal morbidity and excellent cosmetic results. In spite of the current trend toward endonasal endoscopic management of skull base tumors, our series presents nine cases of diverse extensive skull base lesions, 33% of which were recurrent. These cases were approached through different transfacial swing osteotomies through the mandible, a midfacial swing, or a zygomaticotemporal osteotomy as dictated by the three-dimensional spatial location of the lesion, and its extent and proximity to vital structures. Access osteotomies ensured complete removal and good results through the most direct and safe route and good vascular control. This reiterated the fact that transfacial approaches still hold a special place in the management of extensive skull base lesions. PMID:25083368

[Analysis of the clinical course of disease and subsequent dialysis therapy in a group of patients with rheumatoid arthritis and end-stage renal disease].

PubMed

Majdan, Maria; Stepniak, Cezary; Piotrowicz, Sebastian; Broniek, Karina; Blajer, Beata; Bednarek-Skublewska, Anna

2005-04-01

The chronic nephropathy is often present in pts with rheumatoid arthritis (RA). In the study the authors retrospectively analyzed the clinical course of the disease and outcomes of subsequent dialysotherapy in a group of pts with RA and end-stage renal disease ESRD. During last 5 years ESRD connected with RA was found in 10 (8 F, 2 M) pts out of 325 chronically dialyzed pts (peritoneal dialysis and hemodialysis) representing 3,1% of pts. The mean age at the initiation of dialysotherapy in these pts was 62,8 +/- 10,2 (range 46-76) years. Mean time from the diagnosis of RA to the start of dialysotherapy was 18,8 +/- 11,6 (range 5-40) years. Earlier the patients were treated with many disease modifying antirheumatic drugs (DMARDS) also with glucocorticosteroids and many nonsteroidal anti-inflammatory drugs. It means that they had rather aggressive type of RA. Amyloidosis was histological confirmed in 6 pts (4 F, 2 M). Peritoneal dialysis (PD) was the first choice therapy in 8 pts (2 on APD, 6 on CAPD). The main complication was increased incidence of peritonitis. 3 pts died on PD after 5, 9, 24 months (respectively) of CAPD treatment. 3 pts were transferred to HD after 5, 15, 18 (respectively) months of CAPD because of recurrent peritonitis. 2 pts up to date continue PD (one 12 months, the second 46 months on CAPD). In 5 pts who needed hemodialysis treatment there have been very serious problems with permanent vascular access formation. All used permanent indwelling catheters (Permcath). We concluded that: occurrence of ESRD in pts with RA was connected with aggressive type of disease. Pts with RA represent a dialysis group that is particularly prone to complications of PD (enteric peritonitis) and HD (vascular access problems). It seems to be connected with secondary vasculitis often found in pts with aggressive type of RA.

The Combination of Sonography and Physical Examination Improves the Patency and Suitability of Hemodialysis Arteriovenous Fistula in Vascular Access.

PubMed

Mat Said, Normawati; Musa, Kamarul Imran; Mohamed Daud, Mohamed Ashraf; Haron, Juhara

2016-07-01

We compared the patency and the suitability of arteriovenous fistula (AVF) created for vascular access by two approaches: (a) physical examination with preoperative vascular mapping and (b) physical examination alone. We compared the patency and the suitability of AVF created in patients for dialysis. There were two cohorts of patients of 79 patients each: (a) patients with AVF created based on the combination of physical examination and preoperative vascular mapping (PE+VM) and (b) patients with AVF created based on physical examination (PE) alone. Fistula patency is defined as clinical detection of thrill (or auscultation) of murmur over the fistula and coded as having thrills (patent) versus not having thrills (not patent). Suitability of fistula is defined as functioning AVF (AVF can be adequately used via 2-needle cannulation for dialysis) and coded as suitable versus not suitable. AVF created after the preoperative vascular mapping (PE+VM) has 5.70 (at six weeks) and 3.76 (at three months) times higher chance for patency, and 3.08 times higher chance for suitable AVF for dialysis than AVF created after the physical examination (PE) alone. Physical examination with preoperative ultrasound mapping (PE+VM) significantly improves the short term patency and the suitability of AVF for dialysis.

Google Maps offers a new way to evaluate claudication.

PubMed

Khambati, Husain; Boles, Kim; Jetty, Prasad

2017-05-01

Accurate determination of walking capacity is important for the clinical diagnosis and management plan for patients with peripheral arterial disease. The current "gold standard" of measurement is walking distance on a treadmill. However, treadmill testing is not always reflective of the patient's natural walking conditions, and it may not be fully accessible in every vascular clinic. The objective of this study was to determine whether Google Maps, the readily available GPS-based mapping tool, offers an accurate and accessible method of evaluating walking distances in vascular claudication patients. Patients presenting to the outpatient vascular surgery clinic between November 2013 and April 2014 at the Ottawa Hospital with vasculogenic calf, buttock, and thigh claudication symptoms were identified and prospectively enrolled in our study. Onset of claudication symptoms and maximal walking distance (MWD) were evaluated using four tools: history; Walking Impairment Questionnaire (WIQ), a validated claudication survey; Google Maps distance calculator (patients were asked to report their daily walking routes on the Google Maps-based tool runningmap.com, and walking distances were calculated accordingly); and treadmill testing for onset of symptoms and MWD, recorded in a double-blinded fashion. Fifteen patients were recruited for the study. Determination of walking distances using Google Maps proved to be more accurate than by both clinical history and WIQ, correlating highly with the gold standard of treadmill testing for both claudication onset (r = .805; P < .001) and MWD (r = .928; P < .0001). In addition, distances were generally under-reported on history and WIQ. The Google Maps tool was also efficient, with reporting times averaging below 4 minutes. For vascular claudicants with no other walking limitations, Google Maps is a promising new tool that combines the objective strengths of the treadmill test and incorporates real-world walking environments. It offers an accurate, efficient, inexpensive, and readily accessible way to assess walking distances in patients with peripheral vascular disease. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Factors Affecting Hemodialysis Adequacy in Cohort of Iranian Patient with End Stage Renal Disease.

PubMed

Shahdadi, Hosein; Balouchi, Abbas; Sepehri, Zahra; Rafiemanesh, Hosein; Magbri, Awad; Keikhaie, Fereshteh; Shahakzehi, Ahmad; Sarjou, Azizullah Arbabi

2016-08-01

There are many factors that can affect dialysis adequacy; such as the type of vascular access, filter type, device used, and the dose, and rout of erythropoietin stimulation agents (ESA) used. The aim of this study was investigating factors affecting Hemodialysis adequacy in cohort of Iranian patient with end stage renal disease (ESRD). This is a cross-sectional study conducted on 133 Hemodialysis patients referred to two dialysis units in Sistan-Baluchistan province in the cities of Zabol and Iranshahr, Iran. We have looked at, (the effects of the type of vascular access, the filter type, the device used, and the dose, route of delivery, and the type of ESA used) on Hemodialysis adequacy. Dialysis adequacy was calculated using kt/v formula, two-part information questionnaire including demographic data which also including access type, filter type, device used for hemodialysis (HD), type of Eprex injection, route of administration, blood groups and hemoglobin response to ESA were utilized. The data was analyzed using the SPSS v16 statistical software. Descriptive statistical methods, Mann-Whitney statistical test, and multiple regressions were used when applicable. The range of calculated dialysis adequacy is 0.28 to 2.39 (units of adequacy of dialysis). 76.7% of patients are being dialyzed via AVF and 23.3% of patients used central venous catheters (CVC). There was no statistical significant difference between dialysis adequacy, vascular access type, device used for HD (Fresenius and B. Braun), and the filter used for HD (p> 0.05). However, a significant difference was observed between the adequacy of dialysis and Eprex injection and patients' time of dialysis (p <0.05). Subcutaneous ESA (Eprex) injection and dialysis shift (being dialyzed in the morning) can have positive impact on dialysis adequacy. Patients should be educated on the facts that the type of device used for HD and the vascular access used has no significant effects on dialysis adequacy.

A Novel Design of Autonomously Healed Concrete: Towards a Vascular Healing Network

PubMed Central

Minnebo, Pieter; Thierens, Glenn; De Valck, Glenn; Van Tittelboom, Kim; De Belie, Nele; Van Hemelrijck, Danny; Tsangouri, Eleni

2017-01-01

Concrete is prone to crack formation in the tensile zone, which is why steel reinforcement is introduced in these zones. However, small cracks could still arise, which give liquids and gasses access to the reinforcement causing it to corrode. Self-healing concrete repairs and seals these small (300 µm) cracks, preventing the development of corrosion. In this study, a vascular system, carrying the healing agent, is developed. It consists of tubes connected to a 3D printed distribution piece. This distribution piece has four outlets that are connected to the tubes and has one inlet, which is accessible from outside. Several materials were considered for the tubes, i.e., polymethylmethacrylate, starch, inorganic phosphate cement and alumina. Three-point-bending and four-point-bending tests proved that self-healing and multiple self-healing is possible with this developed vascular system. PMID:28772409

Central venous stenosis in haemodialysis patients without a previous history of catheter placement.

PubMed

Oguzkurt, Levent; Tercan, Fahri; Yildirim, Sedat; Torun, Dilek

2005-08-01

To evaluate dialysis history, imaging findings and outcome of endovascular treatment in six patients with central venous stenosis without a history of previous catheter placement. Between April 2000 and June 2004, six (10%) of 57 haemodialysis patients had stenosis of a central vein without a previous central catheter placement. Venography findings and outcome of endovascular treatment in these six patients were retrospectively evaluated. Patients were three women (50%) and three men aged 32-60 years (mean age: 45 years) and all had massive arm swelling as the main complaint. The vascular accesses were located at the elbow in five patients and at the wrist in one patient. Three patients had stenosis of the left subclavian vein and three patients had stenosis of the left brachiocephalic vein. The mean duration of the vascular accesses from the time of creation was 25.1 months. Flow volumes of the vascular access were very high in four patients who had flow volume measurement. The mean flow volume was 2347 ml/min. One of three patients with brachiocephalic vein stenosis had compression of the vein by the brachiocephalic artery. All the lesions were first treated with balloon angioplasty and two patients required stent placement on long term. Number of interventions ranged from 1 to 4 (mean: 2.1). Symptoms resolved in five patients and improved in one patient who had a stent placed in the left BCV. Central venous stenosis in haemodialysis patients without a history of central venous catheterization tends to occur or be manifested in patients with a proximal permanent vascular access with high flow rates. Balloon angioplasty with or without stent placement offers good secondary patency rates in mid-term.

Some old drugs improve late primary patency rate of native arteriovenous fistulas in hemodialysis patients.

PubMed

Righetti, Marco; Ferrario, GianMichele; Serbelloni, Paola; Milani, Silvana; Tommasi, Adalberto

2009-01-01

Vascular access failure causes 20% of all hospitalizations of dialysis patients. Native arteriovenous fistulas, the best type of dialysis vascular access, have a 1-year primary patency rate that is extremely variable, ranging 40-80%. Neointimal hyperplasia is the most important cause of arteriovenous fistula late primary dysfunction. In recent years the arteriovenous fistula late primary patency rate has not improved because of the increase of old uremic patients with a high number of comorbidities and the lack of new therapeutic interventions. Therefore, we performed a long-term case-control study to analyze which factors or drugs may affect native arteriovenous fistula late primary patency rate in 60 incident hemodialysis patients. The arteriovenous fistula late primary patency rate was 75.1% after 12 months, 58.5% after 24 months, and 50% after 987 days. Homocysteine levels during follow-up had a significant direct association with vascular access failure (event vs. event-free 28.5+/-1.9 vs. 22.3+/-1.2 micromol/L, p<0.01). Folate values had a trend toward an inverse relationship with arteriovenous fistula failure (event vs. event-free 11.5+/-1.2 vs. 14.6 vs. 1.1 ng/mL, p=0.06). Patients treated with folic acid and/or statin had an arteriovenous fistula late primary patency rate significantly higher than patients without folic acid and statin therapy, respectively, 81.7% vs. 66% after 1 year and 71.5% vs. 39.1% after 2 years (p=0.02). Many other factors were not associated with vascular access failure. Statin and homocysteine-lowering folic acid therapy is associated with prolonged arteriovenous fistula survival. It is important to perform randomized trials to verify our observation.

Hindlimb heating increases vascular access of large molecules to murine tibial growth plates measured by in vivo multiphoton imaging

PubMed Central

Efaw, Morgan L.; Williams, Rebecca M.

2013-01-01

Advances in understanding the molecular regulation of longitudinal growth have led to development of novel drug therapies for growth plate disorders. Despite progress, a major unmet challenge is delivering therapeutic agents to avascular-cartilage plates. Dense extracellular matrix and lack of penetrating blood vessels create a semipermeable “barrier,” which hinders molecular transport at the vascular-cartilage interface. To overcome this obstacle, we used a hindlimb heating model to manipulate bone circulation in 5-wk-old female mice (n = 22). Temperatures represented a physiological range of normal human knee joints. We used in vivo multiphoton microscopy to quantify temperature-enhanced delivery of large molecules into tibial growth plates. We tested the hypothesis that increasing hindlimb temperature from 22°C to 34°C increases vascular access of large systemic molecules, modeled using 10, 40, and 70 kDa dextrans that approximate sizes of physiological regulators. Vascular access was quantified by vessel diameter, velocity, and dextran leakage from subperichondrial plexus vessels and accumulation in growth plate cartilage. Growth plate entry of 10 kDa dextrans increased >150% at 34°C. Entry of 40 and 70 kDa dextrans increased <50%, suggesting a size-dependent temperature enhancement. Total dextran levels in the plexus increased at 34°C, but relative leakage out of vessels was not temperature dependent. Blood velocity and vessel diameter increased 118% and 31%, respectively, at 34°C. These results demonstrate that heat enhances vascular carrying capacity and bioavailability of large molecules around growth plates, suggesting that temperature could be a noninvasive strategy for modulating delivery of therapeutics to impaired growth plates of children. PMID:24371019

Strategies of arteriovenous dialysis access.

PubMed

Weiswasser, Jonathan M; Kellicut, Dwight; Arora, Subodh; Sidawy, Anton N

2004-03-01

Surgical management of the patient who requires hemodialysis access, while continuing to demand more attention from the vascular surgeon, suffers from discrepancies of approach and strategy. With the increase in incidence of dialysis dependent renal failure among our population, many have attempted to present a uniform, logical strategy with which the vascular surgeon can most effectively treat the hemodialysis patient in the long term. Most notably, the multidisciplinary Dialysis Outcomes Quality Initiative (DOQI) guidelines present the surgeon with a rough outline of hemodialysis access insertion strategy, and it has become nationally recognized as an acceptable summary of treatment strategy and goals. The decision as to the most appropriate surgical access to offer a patient depends on immediate need for hemodialysis, history and physical examination findings, and suitability of available veins in the extremity. While percutaneous, catheter based access affords the luxury of immediate access, these devices suffer from several complicating factors, such as infection, and damage to large, proximal veins. For long-term access, the autogenous access, while perhaps less successful in the immediate short term, is always the preferred access type given its favorable longevity. The surgeons should focus on sites distally on the extremity, reserving proximal sites for potential future access insertions should the primary access fail. In the absence of suitable vein, prosthetic access may be considered. When both the upper and lower aspects of both upper extremities have been exhausted, the surgeon should consider access insertion elsewhere, such as the lower extremity.

[Comparative study of PTFE grafts in forearm vs cuffed permanent catheters].

PubMed

Moyano, M J; Salgueira, M; Aresté, N; Escalera, B; del Toro, N; Jiménez-Víbora, E; Martínez-Puerto, A I; Molas, J R; Palma, A

2006-01-01

As is universally accepted the best form of permanent vascular access for haemodialysis is the native arteriovenous fistula. A second and third options are the politetrafluoroethylene (PTFE) AV grafts and the cuffed, tunneled, internal catheters. The overall performance and complications of catheters is clearly inferior to AV fistula. There are not many studies that compare permanent catheters to grafts in terms of functionality, survival and complications. We analyzed 81 vascular accesses carried out from october 99 to december 03 in 59 patients and during a follow-up period of 35 months. Two groups were considered. Group 1, catheters (n 42) and group 2, grafts (n 39). Clinical aspects, comorbidity index (Wright and Kanh), dialysis dose and complications and survival of the access were registered. Both groups were similar in age, sex, time on haemodialysis, number of previous accesses and hospitalization days. Cardiovascular morbidity and comorbidity index were significantly higher in patients with catheter. While blood flow during dialysis was higher in grafts both groups showed no significant differences in parameters of efficacy of dialysis (Kt/V, TAC BUN and PCRn). Serum albumin was lower in patients with catheter. The number of accesses that failed was higher in the graft group being thrombosis the main complication followed by infection. Kaplan-Meier curves showed better accumulated survival of permanent catheters versus grafts (61,4% vs 9,8% at 35 months). The most frequent complication of catheter was infection while in the case of grafts it was thrombosis followed by infection. Although they were placed in patients with higher comorbidity, cuffed, tunneled catheters showed less number of complications and better survival than PTFE grafts in our patients in haemodialysis. The main cause of failure of both vascular access was thrombosis followed by infection. The dose of dialysis obtained was no different in both groups. Cuffed, tunneled permanent catheters are a very interesting option in a number of patients in haemodialysis and they can be an option to consider in those patients with vascular difficulties and higher comorbidities.

Virtual reality: emerging role of simulation training in vascular access.

PubMed

Davidson, Ingemar J A; Lok, Charmaine; Dolmatch, Bart; Gallieni, Maurizio; Nolen, Billy; Pittiruti, Mauro; Ross, John; Slakey, Douglas

2012-11-01

Evolving new technologies in vascular access mandate increased attention to patient safety; an often overlooked yet valuable training tool is simulation. For the end-stage renal disease patient, simulation tools are effective for all aspects of creating access for peritoneal dialysis and hemodialysis. Based on aviation principles, known as crew resource management, we place equal emphasis on team training as individual training to improve interactions between team members and systems, cumulating in improved safety. Simulation allows for environmental control and standardized procedures, letting the trainee practice and correct mistakes without harm to patients, compared with traditional patient-based training. Vascular access simulators range from suture devices, to pressurized tunneled conduits for needle cannulation, to computer-based interventional simulators. Simulation training includes simulated case learning, root cause analysis of adverse outcomes, and continual update and refinement of concepts. Implementation of effective human to complex systems interaction in end-stage renal disease patients involves a change in institutional culture. Three concepts discussed in this article are as follows: (1) the need for user-friendly systems and technology to enhance performance, (2) the necessity for members to both train and work together as a team, and (3) the team assigned to use the system must test and practice it to a proficient level before safely using the system on patients. Copyright © 2012 Elsevier Inc. All rights reserved.

An Automated Mouse Tail Vascular Access System by Vision and Pressure Feedback.

PubMed

Chang, Yen-Chi; Berry-Pusey, Brittany; Yasin, Rashid; Vu, Nam; Maraglia, Brandon; Chatziioannou, Arion X; Tsao, Tsu-Chin

2015-08-01

This paper develops an automated vascular access system (A-VAS) with novel vision-based vein and needle detection methods and real-time pressure feedback for murine drug delivery. Mouse tail vein injection is a routine but critical step for preclinical imaging applications. Due to the small vein diameter and external disturbances such as tail hair, pigmentation, and scales, identifying vein location is difficult and manual injections usually result in poor repeatability. To improve the injection accuracy, consistency, safety, and processing time, A-VAS was developed to overcome difficulties in vein detection noise rejection, robustness in needle tracking, and visual servoing integration with the mechatronics system.

Virtual-Reality Simulator System for Double Interventional Cardiac Catheterization Using Fractional-Order Vascular Access Tracker and Haptic Force Producer

PubMed Central

Chen, Guan-Chun; Lin, Chia-Hung; Hsieh, Kai-Sheng; Du, Yi-Chun; Chen, Tainsong

2015-01-01

This study proposes virtual-reality (VR) simulator system for double interventional cardiac catheterization (ICC) using fractional-order vascular access tracker and haptic force producer. An endoscope or a catheter for diagnosis and surgery of cardiovascular disease has been commonly used in minimally invasive surgery. It needs specific skills and experiences for young surgeons or postgraduate year (PGY) students to operate a Berman catheter and a pigtail catheter in the inside of the human body and requires avoiding damaging vessels. To improve the training in inserting catheters, a double-catheter mechanism is designed for the ICC procedures. A fractional-order vascular access tracker is used to trace the senior surgeons' consoled trajectories and transmit the frictional feedback and visual feedback during the insertion of catheters. Based on the clinical feeling through the aortic arch, vein into the ventricle, or tortuous blood vessels, haptic force producer is used to mock the elasticity of the vessel wall using voice coil motors (VCMs). The VR establishment with surgeons' consoled vessel trajectories and hand feeling is achieved, and the experimental results show the effectiveness for the double ICC procedures. PMID:26171419

Diagnostic Accuracy of Computer Tomography Angiography and Magnetic Resonance Angiography in the Stenosis Detection of Autologuous Hemodialysis Access: A Meta-Analysis

PubMed Central

Liu, Shiyuan

2013-01-01

Purpose To compare the diagnostic performances of computer tomography angiography (CTA) and magnetic resonance angiography (MRA) for detection and assessment of stenosis in patients with autologuous hemodialysis access. Materials and Methods Search of PubMed, MEDLINE, EMBASE and Cochrane Library database from January 1984 to May 2013 for studies comparing CTA or MRA with DSA or surgery for autologuous hemodialysis access. Eligible studies were in English language, aimed to detect more than 50% stenosis or occlusion of autologuous vascular access in hemodialysis patients with CTA and MRA technology and provided sufficient data about diagnosis performance. Methodological quality was assessed by the Quality Assessment of Diagnostic Studies (QUADAS) instrument. Sensitivities (SEN), specificities (SPE), positive likelihood ratio (PLR), negative likelihood values (NLR), diagnostic odds ratio (DOR) and areas under the receiver operator characteristic curve (AUC) were pooled statistically. Potential threshold effect, heterogeneity and publication bias was evaluated. The clinical utility of CTA and MRA in detection of stenosis was also investigated. Result Sixteen eligible studies were included, with a total of 500 patients. Both CTA and MRA were accurate modality (sensitivity, 96.2% and 95.4%, respectively; specificity, 97.1 and 96.1%, respectively; DOR [diagnostic odds ratio], 393.69 and 211.47, respectively) for hemodialysis vascular access. No significant difference was detected between the diagnostic performance of CTA (AUC, 0.988) and MRA (AUC, 0.982). Meta-regression analyses and subgroup analyses revealed no statistical difference. The Deek’s funnel plots suggested a publication bias. Conclusion Diagnostic performance of CTA and MRA for detecting stenosis of hemodialysis vascular access had no statistical difference. Both techniques may function as an alternative or an important complement to conventional digital subtraction angiography (DSA) and may be able to help guide medical management. PMID:24194928

Future research directions to improve fistula maturation and reduce access failure

PubMed Central

Hu, Haidi; Patel, Sandeep; Hanisch, Jesse J.; Santana, Jeans M.; Hashimoto, Takuya; Bai, Hualong; Kudze, Tambudzai; Foster, Trenton R.; Guo, Jianming; Yatsula, Bogdan; Tsui, Janice; Dardik, Alan

2016-01-01

With the increasing prevalence of end stage renal disease there is a growing need for hemodialysis. Arteriovenous fistulae (AVF) are the preferred type of vascular access for hemodialysis but maturation and failure continue to present significant barriers to successful fistula use. AVF maturation integrates outward remodeling with vessel wall thickening in response to drastic hemodynamic changes, in the setting of uremia, systemic inflammation, oxidative stress and preexistent vascular pathology. AVF can fail due to both failure to mature adequately to support hemodialysis, as well as development of neointimal hyperplasia (NIH) that narrows the AVF lumen, typically near the fistula anastomosis. Failure due to NIH involves vascular cell activation and migration and extracellular matrix remodeling with complex interactions of growth factors, adhesion molecules, inflammatory mediators, and chemokines, all of which result in maladaptive remodeling. Different strategies have been proposed to prevent and treat AVF failure, based on current understanding of the modes and pathology of access failure; these approaches range from appropriate patient selection and use of alternative surgical strategies for fistula creation, to the use of novel interventional techniques or drugs to treat failing fistulae. Effective treatments to prevent or treat AVF failure requires a multidisciplinary approach involving nephrologists, vascular surgeons and interventional radiologists, allowing careful patient selection and the use of tailored systemic or localized interventions to improve patient-specific outcomes. This review provides contemporary information on the underlying mechanisms of AVF maturation and failure and discusses the broad spectrum of options that can be tailored for specific therapy. PMID:28779782

Future research directions to improve fistula maturation and reduce access failure.

PubMed

Hu, Haidi; Patel, Sandeep; Hanisch, Jesse J; Santana, Jeans M; Hashimoto, Takuya; Bai, Hualong; Kudze, Tambudzai; Foster, Trenton R; Guo, Jianming; Yatsula, Bogdan; Tsui, Janice; Dardik, Alan

2016-12-01

With the increasing prevalence of end-stage renal disease, there is a growing need for hemodialysis. Arteriovenous fistulae (AVF) are the preferred type of vascular access for hemodialysis, but maturation and failure continue to present significant barriers to successful fistula use. AVF maturation integrates outward remodeling with vessel wall thickening in response to drastic hemodynamic changes in the setting of uremia, systemic inflammation, oxidative stress, and pre-existent vascular pathology. AVF can fail due to both failure to mature adequately to support hemodialysis and development of neointimal hyperplasia that narrows the AVF lumen, typically near the fistula anastomosis. Failure due to neointimal hyperplasia involves vascular cell activation and migration and extracellular matrix remodeling with complex interactions of growth factors, adhesion molecules, inflammatory mediators, and chemokines, all of which result in maladaptive remodeling. Different strategies have been proposed to prevent and treat AVF failure based on current understanding of the modes and pathology of access failure; these approaches range from appropriate patient selection and use of alternative surgical strategies for fistula creation, to the use of novel interventional techniques or drugs to treat failing fistulae. Effective treatments to prevent or treat AVF failure require a multidisciplinary approach involving nephrologists, vascular surgeons, and interventional radiologists, careful patient selection, and the use of tailored systemic or localized interventions to improve patient-specific outcomes. This review provides contemporary information on the underlying mechanisms of AVF maturation and failure and discusses the broad spectrum of options that can be tailored for specific therapy. Published by Elsevier Inc.

A Predictive Framework to Elucidate Venous Stenosis: CFD & Shape Optimization.

PubMed

Javid Mahmoudzadeh Akherat, S M; Cassel, Kevin; Boghosian, Michael; Hammes, Mary; Coe, Fredric

2017-07-01

The surgical creation of vascular accesses for renal failure patients provides an abnormally high flow rate conduit in the patient's upper arm vasculature that facilitates the hemodialysis treatment. These vascular accesses, however, are very often associated with complications that lead to access failure and thrombotic incidents, mainly due to excessive neointimal hyperplasia (NH) and subsequently stenosis. Development of a framework to monitor and predict the evolution of the venous system post access creation can greatly contribute to maintaining access patency. Computational fluid dynamics (CFD) has been exploited to inspect the non-homeostatic wall shear stress (WSS) distribution that is speculated to trigger NH in the patient cohort under investigation. Thereafter, CFD in liaison with a gradient-free shape optimization method has been employed to analyze the deformation modes of the venous system enduring non-physiological hemodynamics. It is observed that the optimally evolved shapes and their corresponding hemodynamics strive to restore the homeostatic state of the venous system to a normal, pre-surgery condition. It is concluded that a CFD-shape optimization coupling that seeks to regulate the WSS back to a well-defined physiological WSS target range can accurately predict the mode of patient-specific access failure.

Three-dimensional printed ultrasound and photoacoustic training phantoms for vasculature access (Conference Presentation)

NASA Astrophysics Data System (ADS)

Nikitichev, Daniil I.; Xia, Wenfeng; West, Simeon J.; Desjardins, Adrien E.; Ourselin, Sebastien; Vercauteren, Tom

2017-03-01

Ultrasound (US) imaging is widely used to guide vascular access procedures such as arterial and venous cannulation. As needle visualisation with US imaging can be very challenging, it is easy to misplace the needle in the patient and it can be life threating. Photoacoustic (PA) imaging is well suited to image medical needles and catheters that are commonly used for vascular access. To improve the success rate, a certain level of proficiency is required that can be gained through extensive practice on phantoms. Unfortunately, commercial training phantoms are expensive and custom-made phantoms usually do not replicate the anatomy very well. Thus, there is a great demand for more realistic and affordable ultrasound and photoacoustic imaging phantoms for vasculature access procedures training. Three-dimensional (3D) printing can help create models that replicate complex anatomical geometries. However, the available 3D printed materials do not possess realistic tissue properties. Alternatively, tissue-mimicking materials can be employed using casting and 3D printed moulds but this approach is limited to the creation of realistic outer shapes with no replication of complex internal structures. In this study, we developed a realistic vasculature access phantom using a combination of mineral oil based materials as background tissue and a non-toxic, water dissolvable filament material to create complex vascular structure using 3D printing. US and PA images of the phantoms comprising the complex vasculature network were acquired. The results show that 3D printing can facilitate the fabrication of anatomically realistic training phantoms, with designs that can be customized and shared electronically.

Vascular access for hemodialysis: current perspectives

PubMed Central

Santoro, Domenico; Benedetto, Filippo; Mondello, Placido; Pipitò, Narayana; Barillà, David; Spinelli, Francesco; Ricciardi, Carlo Alberto; Cernaro, Valeria; Buemi, Michele

2014-01-01

A well-functioning vascular access (VA) is a mainstay to perform an efficient hemodialysis (HD) procedure. There are three main types of access: native arteriovenous fistula (AVF), arteriovenous graft, and central venous catheter (CVC). AVF, described by Brescia and Cimino, remains the first choice for chronic HD. It is the best access for longevity and has the lowest association with morbidity and mortality, and for this reason AVF use is strongly recommended by guidelines from different countries. Once autogenous options have been exhausted, prosthetic fistulae become the second option of maintenance HD access alternatives. CVCs have become an important adjunct in maintaining patients on HD. The preferable locations for insertion are the internal jugular and femoral veins. The subclavian vein is considered the third choice because of the high risk of thrombosis. Complications associated with CVC insertion range from 5% to 19%. Since an increasing number of patients have implanted pacemakers and defibrillators, usually inserted via the subclavian vein and superior vena cava into the right heart, a careful assessment of risk and benefits should be taken. Infection is responsible for the removal of about 30%–60% of HD CVCs, and hospitalization rates are higher among patients with CVCs than among AVF ones. Proper VA maintenance requires integration of different professionals to create a VA team. This team should include a nephrologist, radiologist, vascular surgeon, infectious disease consultant, and members of the dialysis staff. They should provide their experience in order to give the best options to uremic patients and the best care for their VA. PMID:25045278

[Endovascular interventions for multiple trauma].

PubMed

Kinstner, C; Funovics, M

2014-09-01

In recent years interventional radiology has significantly changed the management of injured patients with multiple trauma. Currently nearly all vessels can be reached within a reasonably short time with the help of specially preshaped catheters and guide wires to achieve bleeding control of arterial und venous bleeding. Whereas bleeding control formerly required extensive open surgery, current interventional methods allow temporary vessel occlusion (occlusion balloons), permanent embolization and stenting. In injured patients with multiple trauma preinterventional procedural planning is performed with the help of multidetector computed tomography whenever possible. Interventional radiology not only allows minimization of therapeutic trauma but also a considerably shorter treatment time. Interventional bleeding control has developed into a standard method in the management of vascular trauma of the chest and abdomen as well as in vascular injuries of the upper and lower extremities when open surgical access is associated with increased risk. Additionally, pelvic trauma, vascular trauma of the superior thoracic aperture and parenchymal arterial lacerations of organs that can be at least partially preserved are primarily managed by interventional methods. In an interdisciplinary setting interventional radiology provides a safe and efficient means of rapid bleeding control in nearly all vascular territories in addition to open surgical access.

[Stents in dialysis vascular access--do they promise improved high quality prolonged access use].

PubMed

Klein, Osnat; Plotkin, Eleonora; Gritun, Igal; Verner, Myriam; Lehmann, J M; Rathaus, Mauro; Bernheim, Jacques

2008-02-01

The life expectancy of dialysis patients depends, to a large extent, on blood access which provides uninterrupted and efficient treatment. Dialysis access created by a direct anastomosis between artery and vein usually allows normal dialysis for many years. Blood access by a bridge graft between artery and vein functions for a much shorter time and occludes chiefly because of endothelial hyperplasia at the graft vein anastomosis. This type of fistula is created when the veins of the patient are small. During the last few years the dialysis population is increasingly composed of adult and elderly patients suffering from diabetes mellitus, hypertension, dyslipidemias and atheromatous vascular disease so that a relatively large proportion of dialysis accesses are created using a bridge graft. Since we currently do not have the knowledge of how to arrest or delay the processes which lead to access occlusion, attempts are made to implement prophylactic strategies, find stenoses and dilate them before the access fails. Up to date, controlled trials have not succeeded in proving that this method prolongs access use. These trials did not describe the use of stents following dilatation. Between July 2002 and May 2005, 238 angiographies were performed on blood accesses including 179 angioplasties of stenoses. In sixteen patients a stent was deployed during the angioplasty. In ten patients dialysis was performed using the same access up to the end of the study period, an average of 43 months from the creation of the access. Three patients died with a functioning access and in three the access occluded during the period of followup. This study shows that the use of stents following angioplasty of dialysis access stenoses can improve the duration of use of accesses created through grafts.

Creation of dialysis vascular access with normal flow increases brain natriuretic peptide levels.

PubMed

Malík, Jan; Tuka, Vladimir; Krupickova, Zdislava; Chytilova, Eva; Holaj, Robert; Slavikova, Marcela

2009-12-01

Chronic heart failure is very common in hemodialyzed patients due to several factors such as intermittent volume overload, anemia, and hypertension. Dialysis access flow is usually considered to have a minor effect. We hypothesized that creation of dialysis access with "normal" flow would lead to elevation of B-type natriuretic peptide (BNP), which is a sensitive marker of heart failure. We included subjects with a newly created, well-functioning vascular access and normal left ventricular ejection fraction. They were examined before access creation (baseline), then again 6 weeks and 6 months after the surgery. Only subjects with access flow (Qa) < 1500 ml/min were included. Changes of BNP levels and their relation to access flow were studied. We examined 35 subjects aged 60.6 +/- 13.5 years. Qa was 789 +/- 361 and 823 +/- 313 ml/min at 6 weeks and 6 months after the surgery, respectively. Within 6 weeks after access creation, BNP rose from 217 (294) to 267 (550) ng/l (median (quartile range)) with P = 0.003. Qa was significantly related to BNP levels 6 weeks after access creation (r = 0.37, P = 0.036). Six months after access creation, there was only a trend of BNP decrease (235 (308) ng/l, P = 0.44). Creatinine, blood urea nitrogen and hemoglobin levels as well as patients' weight did not change significantly. Creation of dialysis access with "normal" flow volume leads to significant increase of BNP, which is related to the value of access flow. The increase of BNP probably mirrors worsening of clinically silent heart failure.

Ultrasound-Guided Angioplasty of Dysfunctional Vascular Access for Haemodialysis. The Pros and Cons

DOE Office of Scientific and Technical Information (OSTI.GOV)

García-Medina, J., E-mail: josegmedina57@gmail.com; García-Alfonso, J. J., E-mail: juanjozarandieta@gmail.com

PurposeTo describe the benefits and the disadvantages of angioplasty in dialysis fistulas using only ultrasound guidance.Materials and MethodsThis is a prospective study in 132 failing or non-maturing arteriovenous accesses that underwent 189 ultrasound-guided balloon angioplasties. The technical success was defined as non-use of X-ray fluoroscopy during the procedure.Results127 procedures (67%) were successfully completed without fluoroscopy. Most failures were due to difficulty to traverse aneurismal segments, as well as anastomotic stenoses. Including initial failures, the primary patency rates at 6, 12 months and 2 years were 75 ± 3, 41 ± 3 and 14 ± 2%, respectively.ConclusionEndovascular repair of the dysfunctional vascular access for haemodialysis under ultrasound guidance ismore » feasible and safe in roughly two-thirds of cases.« less

Vascular Sap Proteomics: Providing Insight into Long-Distance Signaling during Stress

PubMed Central

Carella, Philip; Wilson, Daniel C.; Kempthorne, Christine J.; Cameron, Robin K.

2016-01-01

The plant vascular system, composed of the xylem and phloem, is important for the transport of water, mineral nutrients, and photosynthate throughout the plant body. The vasculature is also the primary means by which developmental and stress signals move from one organ to another. Due to practical and technological limitations, proteomics analysis of xylem and phloem sap has been understudied in comparison to accessible sample types such as leaves and roots. However, recent advances in sample collection techniques and mass spectrometry technology are making it possible to comprehensively analyze vascular sap proteomes. In this mini-review, we discuss the emerging field of vascular sap proteomics, with a focus on recent comparative studies to identify vascular proteins that may play roles in long-distance signaling and other processes during stress responses in plants. PMID:27242852

Flagellin peptide flg22 gains access to long-distance trafficking in Arabidopsis via its receptor, FLS2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jelenska, Joanna; Davern, Sandra M.; Standaert, Robert F.

Diverse pathogen-derived molecules, such as bacterial flagellin and its conserved peptide flg22, are recognized in plants via plasma membrane receptors and induce both local and systemic immune responses. The fate of such ligands was unknown: whether and by what mechanism(s) they enter plant cells and whether they are transported to distal tissues. We used biologically active fluorophore and radiolabeled peptides to establish that flg22 moves to distal organs with the closest vascular connections. Remarkably, entry into the plant cell via endocytosis together with the FLS2 receptor is needed for delivery to vascular tissue and long-distance transport of flg22. This contrastsmore » with known routes of long distance transport of other non-cell-permeant molecules in plants, which require membrane-localized transporters for entry to vascular tissue. Thus, a plasma membrane receptor acts as a transporter to enable access of its ligand to distal trafficking routes.« less

Flagellin peptide flg22 gains access to long-distance trafficking in Arabidopsis via its receptor, FLS2

DOE PAGES

Jelenska, Joanna; Davern, Sandra M.; Standaert, Robert F.; ...

2017-03-01

Diverse pathogen-derived molecules, such as bacterial flagellin and its conserved peptide flg22, are recognized in plants via plasma membrane receptors and induce both local and systemic immune responses. The fate of such ligands was unknown: whether and by what mechanism(s) they enter plant cells and whether they are transported to distal tissues. We used biologically active fluorophore and radiolabeled peptides to establish that flg22 moves to distal organs with the closest vascular connections. Remarkably, entry into the plant cell via endocytosis together with the FLS2 receptor is needed for delivery to vascular tissue and long-distance transport of flg22. This contrastsmore » with known routes of long distance transport of other non-cell-permeant molecules in plants, which require membrane-localized transporters for entry to vascular tissue. Thus, a plasma membrane receptor acts as a transporter to enable access of its ligand to distal trafficking routes.« less

Bioengineered vascular scaffolds: the state of the art.

PubMed

Palumbo, Vincenzo D; Bruno, Antonio; Tomasello, Giovanni; Damiano, Giuseppe; Lo Monte, Attilio I

2014-07-31

To date, there is increasing clinical need for vascular substitutes due to accidents, malformations, and ischemic diseases. Over the years, many approaches have been developed to solve this problem, starting from autologous native vessels to artificial vascular grafts; unfortunately, none of these have provided the perfect vascular substitute. All have been burdened by various complications, including infection, thrombogenicity, calcification, foreign body reaction, lack of growth potential, late stenosis and occlusion from intimal hyperplasia, and pseudoaneurysm formation. In the last few years, vascular tissue engineering has emerged as one of the most promising approaches for producing mechanically competent vascular substitutes. Nanotechnologies have contributed their part, allowing extraordinarily biostable and biocompatible materials to be developed. Specifically, the use of electrospinning to manufacture conduits able to guarantee a stable flow of biological fluids and guide the formation of a new vessel has revolutionized the concept of the vascular substitute. The electrospinning technique allows extracellular matrix (ECM) to be mimicked with high fidelity, reproducing its porosity and complexity, and providing an environment suitable for cell growth. In the future, a better knowledge of ECM and the manufacture of new materials will allow us to "create" functional biological vessels - the base required to develop organ substitutes and eventually solve the problem of organ failure.

The Use of ExoSeal Vascular Closure Device for Direct Antegrade Superficial Femoral Artery Puncture Site Hemostasis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rimon, Uri, E-mail: rimonu@sheba.health.gov.il; Khaitovich, Boris, E-mail: borislena@012.net.il; Yakubovich, Dmitry, E-mail: Dmitry.Yakubovitch@sheba.health.gov.il

2015-06-15

PurposeThis study was designed to assess the efficacy and safety of the ExoSeal vascular closure device (VCD) to achieve hemostasis in antegrade access of the superficial femoral artery (SFA).MethodsWe retrospectively reviewed the outcome of ExoSeal VCD used for hemostasis in 110 accesses to the SFA in 93 patients between July 2011 and July 2013. All patients had patent proximal SFA based on computer tomography angiography or ultrasound duplex. Arterial calcifications at puncture site were graded using fluoroscopy. The SFA was accessed in an antegrade fashion with ultrasound or fluoroscopic guidance. In all patients, 5–7F vascular sheaths were used. The ExoSealmore » VCD was applied to achieve hemostasis at the end of the procedure. All patients were clinically examined and had ultrasound duplex exam for any puncture site complications during the 24 h postprocedure.ResultsIn all procedures, the ExoSeal was applied successfully. We did not encounter any device-related technical failure. There were four major complications in four patients (3.6 %): three pseudoaneurysms, which were treated with direct thrombin injection, and one hematoma, which necessitated transfusion of two blood units. All patients with complications were treated with anticoagulation preprocedure or received thrombolytic therapy.ConclusionsThe ExoSeal VCD can be safely used for antegrade puncture of the SFA, with a high procedural success rate (100 %) and a low rate of access site complications (3.6 %)« less

A retrospective comparative study of tunneled haemodialysis catheters inserted through occluded or collateral veins versus conventional methods.

PubMed

Powell, Steven; Chan, Tze Yuan; Bhat, Rammohan; Lam, Kimberly; Narlawar, Ranjeet S; Cullen, Nicola; Littler, Peter

2010-08-01

Tunneled hemodialysis catheters become essential in dialysis access when there is no possibility of using a functioning arteriovenous fistula. Collateral or occluded veins visible on ultrasound are used for puncture and passage of catheters into the central venous system. Chronically occluded veins are crossed with guidewires to allow dilatation and subsequent passage of hemodialysis catheters. We performed a retrospective analysis of patient demographics, comorbidities, procedural complications, functional survival, performance, and history of previous vascular access. The study group was compared with two control groups in which dialysis catheters were inserted either by radiologists in the interventional suite or by clinicians on the wards. Nineteen patients from the study group were compared with same number of patients in both control groups. The mean age of the study group was higher compared with the control groups. There was no significant difference in mean functional survival, infection rates, dialysis pump speeds in the first 2 weeks, and procedural complications between the study group and the controls. The study group had a significantly higher number of previous vascular access interventions, longer dialysis careers, and more comorbidities. Tunneled dialysis catheter placement by way of collateral or occluded veins appears safe and effective. These techniques give the operator further options when faced with patients possessing challenging vascular access. Indeed, there may be a case for preferential use of these veins to keep patent central veins in reserve.

Hyperglycemia-Induced Modulation of the Physiognomy and Angiogenic Potential of Fibroblasts Mediated by Matrix Metalloproteinase-2: Implications for Venous Stenosis Formation Associated with Hemodialysis Vascular Access in Diabetic Milieu.

PubMed

Janardhanan, Rajiv; Kilari, Sreenivasulu; Leof, Edward B; Misra, Sanjay

2015-01-01

It is hypothesized that venous stenosis formation associated with hemodialysis vascular-access failure is caused by hypoxia-mediated fibroblast-to-myofibroblast differentiation accompanied by proliferation and migration, and that diabetic patients have worse clinical outcomes. The aim of this study was to determine the functional and gene expression outcomes of matrix metalloproteinase-2 (Mmp-2) silencing in fibroblasts cultured under hyperglycemia and euglycemia with hypoxic and normoxic stimuli. AKR-2B fibroblasts were stably transduced using lentivirus-mediated shRNA-Mmp-2 or scrambled controls and subjected to hypoxia or normoxia under hyperglycemic or euglycemic conditions for 24 and 72 h. Gene expression of vascular endothelial growth factor-A (Vegf-A), Vegfr-1, Mmp-2, Mmp-9 and tissue inhibitors of matrix metalloproteinases (Timps) were determined by RT-PCR. Collagen I and IV secretion and cellular proliferation and migration were determined. Under hyperglycemic conditions, there is a significant reduction in the average gene expression of Vegf-A and Mmp-9, with an increase in Timp-1 at 24 h of hypoxia (p < 0.05) in Mmp-2-silenced fibroblasts when compared to controls. In addition, there is a decrease in collagen I and IV secretion and cellular migration. The euglycemic cells were able to reverse these findings. These findings demonstrate the rationale for using anti-Mmp-2 therapy in dialysis patients with hemodialysis vascular access in helping to reduce stenosis formation. © 2016 The Author(s) Published by S. Karger AG, Basel.

Rationale, design, and methods for Canadian alliance for healthy hearts and minds cohort study (CAHHM) - a Pan Canadian cohort study.

PubMed

Anand, Sonia S; Tu, Jack V; Awadalla, Philip; Black, Sandra; Boileau, Catherine; Busseuil, David; Desai, Dipika; Després, Jean-Pierre; de Souza, Russell J; Dummer, Trevor; Jacquemont, Sébastien; Knoppers, Bartha; Larose, Eric; Lear, Scott A; Marcotte, Francois; Moody, Alan R; Parker, Louise; Poirier, Paul; Robson, Paula J; Smith, Eric E; Spinelli, John J; Tardif, Jean-Claude; Teo, Koon K; Tusevljak, Natasa; Friedrich, Matthias G

2016-07-27

The Canadian Alliance for Healthy Hearts and Minds (CAHHM) is a pan-Canadian, prospective, multi-ethnic cohort study being conducted in Canada. The overarching objective of the CAHHM is to understand the association of socio-environmental and contextual factors (such as societal structure, activity, nutrition, social and tobacco environments, and access to health services) with cardiovascular risk factors, subclinical vascular disease, and cardiovascular and other chronic disease outcomes. Participants between 35 and 69 years of age are being recruited from existing cohorts and a new First Nations Cohort to undergo a detailed assessment of health behaviours (including diet and physical activity), cognitive function, assessment of their local home and workplace environments, and their health services access and utilization. Physical measures including weight, height, waist/hip circumference, body fat percentage, and blood pressure are collected. In addition, eligible participants undergo magnetic resonance imaging (MRI) of the brain, heart, carotid artery and abdomen to detect early subclinical vascular disease and ectopic fat deposition. CAHHM is a prospective cohort study designed to investigate the impact of community level factors, individual health behaviours, and access to health services, on cognitive function, subclinical vascular disease, fat distribution, and the development of chronic diseases among adults living in Canada.

[Aspects of vascular physiology in clinical and vascular surgical practice: basic principles of vascular mechanics].

PubMed

Nocke, H; Meyer, F; Lessmann, V

2014-10-01

To be able to evaluate properly a vascular problem, basic concepts of vascular physiology need to be considered, as they have been taught in physiology for a long time. This article deals with selected definitions and laws of passive vascular mechanics, subdivided into parameters of vascular filling and parameters of vascular flow. PARAMETERS OF VASCULAR FILLING: During vascular filling the transmural pressure distends the vascular wall until it is balanced by the wall tension. The extent of this distension up to the point of balance depends on the elasticity of the wall. Transmural pressure, wall tension and elasticity are defined, and their respective importance is described by clinical examples, e.g. aneurysm and varix. PARAMETERS OF VASCULAR FLOW: The vascular flow can be divided into stationary and pulsating components. Both components are relevant for the bloodstream. Since the blood flow is directed in the circuit, it can be understood in first approximation as stationary ("direct current").The direct current model uses only the average values of the pulsating variables. The great advantage of the direct current model is that it can be described with simple laws, which are not valid without reservation, but often allow a first theoretical approach to a vascular problem: Ohm's law, driving pressure, flow resistance, Hagen-Poiseuille law, wall shear stress, law of continuity, Bernoulli's equation and Reynold's number are described and associated with clinical examples.The heart is a pressure-suction pump and produces a pulsating flow, the pulse. The pulse runs with pulse wave velocity, which is much larger than the blood flow velocity, through the arterial vascular system. During propagation, the pulse has to overcome the wave resistance (impedance). Wherever the wave resistance changes, e.g., at vascular bifurcations and in the periphery, it comes to reflections. The incident (forward) and reflected (backward) waves are superimposed to yield the resulting pulse wave. This pulse wave allows one to distinguish pressure and flow pulse by measurement. Both are described separately, and their respective clinical meaning is illustrated by appropriate examples, e.g., arterial stiffness and pre-/postocclusive high/low resistance flow, respectively. Georg Thieme Verlag KG Stuttgart · New York.

Novel Method for Exchange of Impella Circulatory Assist Catheter: The "Trojan Horse" Technique.

PubMed

Phillips, Colin T; Tamez, Hector; Tu, Thomas M; Yeh, Robert W; Pinto, Duane S

2017-07-01

Patients with an indwelling Impella may require escalation of hemodynamic support or exchange to another circulatory assistance platform. As such, preservation of vascular access is preferable in cases where anticoagulation cannot be discontinued or to facilitate exchange to an alternative catheter or closure device. Challenges exist in avoiding bleeding and loss of wire access in these situations. We describe a single-access "Trojan Horse" technique that minimizes bleeding while maintaining arterial access for rapid exchange of this percutaneous ventricular assist device.

Permanent vascular access survival in children on long-term chronic hemodialysis.

PubMed

Briones, Liliana; Diaz Moreno, Alexia; Sierre, Sergio; Lopez, Laura; Lipsich, José; Adragna, Marta

2010-09-01

The aim of this study is to report a single-center experience regarding the management and outcome of permanent vascular accesses (VA) in children on chronic hemodialysis (HD). We analyzed the survival of permanent VA in 79 pediatric patients with end-stage renal disease patients on chronic HD between January 2000 and December 2008. One hundred and thirty-seven VA [89 native fistulas (AVFs) and 48 grafts (AVGs)] were created in 79 children. The creation of AVFs was significantly more frequent in children weighing >25 kg and AVGs in children weighing <25 kg (p = 0.003). The 1-year primary patency rate was 50% for AVF and 30% for AVG. The secondary patency rates at 1, 2, and 3 years for AVFs were 73, 50, and 20% and for AVGs were 64, 36, and 20%, respectively. The total number of surgical and endovascular interventions was significantly higher in AVGs (p

Prevalence of difficult venous access and associated risk factors in highly complex hospitalised patients.

PubMed

Armenteros-Yeguas, Victoria; Gárate-Echenique, Lucía; Tomás-López, Maria Aranzazu; Cristóbal-Domínguez, Estíbaliz; Moreno-de Gusmão, Breno; Miranda-Serrano, Erika; Moraza-Dulanto, Maria Inmaculada

2017-12-01

To estimate the prevalence of difficult venous access in complex patients with multimorbidity and to identify associated risk factors. In highly complex patients, factors like ageing, the need for frequent use of irritant medication and multiple venous catheterisations to complete treatment could contribute to exhaustion of venous access. A cross-sectional study was conducted. 'Highly complex' patients (n = 135) were recruited from March 2013-November 2013. The main study variable was the prevalence of difficult venous access, assessed using one of the following criteria: (1) a history of difficulties obtaining venous access based on more than two attempts to insert an intravenous line and (2) no visible or palpable veins. Other factors potentially associated with the risk of difficult access were also measured (age, gender and chronic illnesses). Univariate analysis was performed for each potential risk factor. Factors with p < 0·2 were then included in multivariable logistic regression analysis. Odds ratios were also calculated. The prevalence of difficult venous access was 59·3%. The univariate logistic regression analysis indicated that gender, a history of vascular access complications and osteoarticular disease were significantly associated with difficult venous access. The multivariable logistic regression showed that only gender was an independent risk factor and the odds ratios was 2·85. The prevalence of difficult venous access is high in this population. Gender (female) is the only independent risk factor associated with this. Previous history of several attempts at catheter insertion is an important criterion in the assessment of difficult venous access. The prevalence of difficult venous access in complex patients is 59·3%. Significant risk factors include being female and a history of complications related to vascular access. © 2017 John Wiley & Sons Ltd.

Intraosseous access in neonates and infants: risk of severe complications - a case report.

PubMed

Suominen, P K; Nurmi, E; Lauerma, K

2015-11-01

Gaining vascular access in a neonate during cardiopulmonary resuscitation is crucial and challenging. Intraosseous (IO) access can offer a fast and reliable method for achieving emergency access for fluids and drugs when venous access fails in a critically ill child. IO access can however result in rare, but serious adverse events including compartment syndrome and amputation. We describe a case resulting in leg amputation due to IO infusion in a neonate after resuscitation and therapeutic hypothermia. We compared 10 tibia X-rays in three age groups. The mean medullary diameter of the proximal tibia at the recommended site for IO access was 7 mm in neonate, 10 mm in 1- to 12-month-old infants, and 12 mm in 3- to 4-year-old children. This provides a narrow margin of safety for the correct positioning and the avoidance of dislodgement of the IO needle. The correct position of the IO needle should be confirmed by bone marrow aspiration and fluid bolus. Unnecessary touching of the IO needle after fixing it in place should be avoided by inserting a luer-lock catheter with a three-way stop-cock for IO drug and fluid administration. Regular observation of the circulation and possible swelling of the leg should be performed. The IO administration of inotropic infusions should also be avoided after the initial resuscitation phase. When treating with therapeutic hypothermia, it may be wise to remove the IO needle much earlier than the currently recommended 24 h because of the problems in peripheral circulation and its monitoring. © 2015 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Access to primary health care for acute vascular events in rural low income settings: a mixed methods study.

PubMed

Ahmed, Shyfuddin; Chowdhury, Muhammad Ashique Haider; Khan, Md Alfazal; Huq, Nafisa Lira; Naheed, Aliya

2017-01-18

Cardiovascular diseases (CVDs) are the leading cause of global mortality. Among the CVDs, acute vascular events (AVE) mainly ischemic heart diseases and stroke are the largest contributors. To achieve 25% reduction in preventable deaths from CVDs by 2025, health systems need to be equipped with extended service coverage in order to provide person-centered care. The overall goal of this proposed study is to assess access to health care in-terms of service availability, care seeking patterns and barriers to access care after AVE in rural Bangladesh. We will consider myocardial infarction (MI) and stroke as acute vascular events. We will conduct a mixed methods study in rural Matlab, Bangladesh. This study will comprise of a) health facility survey, b) structured questionnaire interview and c) qualitative study. We will assess service availabilities by creating an inventory of public and private health facilities. Readiness of the facilities to deliver services for AVE will be assessed through a health facility survey using 'service availability and readiness assessment' (SARA) tools of the World Health Organization (WHO). We will interview survivors of AVE and caregivers (present and accompanied the person during the event) of person who died from AVE for exploring patterns of care seeking during an AVE. For exploring barriers to access care for AVE, we will conduct in-depth interview with survivors of AVE and caregivers of the person who died from AVE. We will also conduct key informant interviews with the service providers at primary health care (PHC) facilities and government high level officials at central health administration of Bangladesh. This study will provide a comprehensive picture of access to primary health care services during acute cardiovascular events as stroke & MI in rural context of Bangladesh. It will explore available service facilities in rural area for management, utilization of services and barriers to access care during an acute emergency. This study will help to generate hypothesis, develop programs and policies for better access to care for AVE in similar rural settings considering barriers of access and improving utilization.

Epidemiology, surveillance, and prevention of bloodstream infections in hemodialysis patients.

PubMed

Patel, Priti R; Kallen, Alexander J; Arduino, Matthew J

2010-09-01

Infections cause significant morbidity and mortality in patients undergoing hemodialysis. Bloodstream infections (BSIs) are particularly problematic, accounting for a substantial number of hospitalizations in these patients. Hospitalizations for BSI and other vascular access infections appear to have increased dramatically in hemodialysis patients since 1993. These infections frequently are related to central venous catheter (CVC) use for dialysis access. Regional initiatives that have shown successful decreases in catheter-related BSIs in hospitalized patients have generated interest in replicating this success in outpatient hemodialysis populations. Several interventions have been effective in preventing BSIs in the hemodialysis setting. Avoiding the use of CVCs in favor of access types with lower associated BSI risk is among the most important. When CVCs are used, adherence to evidence-based catheter insertion and maintenance practices can positively influence BSI rates. In addition, facility-level surveillance to detect BSIs and stimulate examination of vascular access use and care practices is essential to a comprehensive approach to prevention. This article describes the current epidemiology of BSIs in hemodialysis patients and effective prevention strategies to decrease the incidence of these devastating infections.

UK Renal Registry 17th Annual Report: Chapter 10 2013 Multisite Dialysis Access Audit in England, Northern Ireland and Wales and 2012 PD One Year Follow-up: National and Centre-specific Analyses.

PubMed

Rao, Anirudh; Pitcher, David; Fluck, Richard; Kumwenda, Mick

2015-01-01

Dialysis access should be timely, minimize complications and maintain functionality. The aim of the second combined vascular and peritoneal dialysis access audit was to examine practice patterns with respect to dialysis access and highlight variations in practice between renal centres. The UK Renal Registry collected centre-specific information on incident vascular and peritoneal dialysis access outcome measures in patients from England, Wales and Northern Ireland (EW&NI), including patient demographics, dialysis access type (at start of dialysis and three months after start of dialysis), surgical assessment and access functionality. Centres who had reported data on incident PD patients for the previous 2012 audit were additionally asked to provide one year follow up data for this group. The findings were compared to the audit measures stated in Renal Association clinical practice guidelines for dialysis access. Fifty-seven centres in EW&NI (representing 92% of all centres) returned data on first access from 3,663 incident HD patients and 1,022 incident PD patients. A strong relationship was seen between surgical assessment and the likelihood of starting HD with an arteriovenous fistula (AVF). Twenty-four centres were at least two standard deviations below the 65% target for incident patients starting haemodialysis on AVF and only eight centres (14%) were within two standard deviations of the 85% target for prevalent haemodialysis patients on AVF. There was wide practice variation across the UK in provision of both HD and PD access which requires further exploration.

Complications with Angio-Seal™ vascular closure devices compared with manual compression after diagnostic cardiac catheterization and percutaneous coronary intervention.

PubMed

Gregory, Deborah; Midodzi, William; Pearce, Neil

2013-12-01

This study assessed and compared vascular complications in CATHs and PCIs using an Angio-Seal™ vascular closure device (VCD) versus manual compression (MC). Secondary data analysis of a population-based multiyear cohort database was conducted to compare femoral access-related vascular outcomes in cardiac procedures using VCD and MC between May 1, 2006 and December 31, 2010. The primary outcome was any vascular complication. Propensity score adjusted analysis was conducted to reduce bias associated with covariate imbalance between the groups compared. Of the 11,897 procedures, 7,063 (59.4%) used a VCD. Vascular complications occurred in 174/8,796 (2.0%) of CATHs and 82/3,004 (2.7%) of PCIs. In the CATH sample, the odds of vascular complication were 57% lower if a VCD was used (OR = 0.43, 95% CI 0.31-0.60). For the PCI sample, the risk was 49% lower if a VCD was used (OR = 0.51, 95% CI 0.31-0.81). A low incidence of vascular complications was observed with the use of an Angio-Seal VCD relative to MC for both procedures. © 2013, Wiley Periodicals, Inc.

A Novel Mammary Fat Pad Transplantation Technique to Visualize the Vessel Generation of Vascular Endothelial Stem Cells.

PubMed

Yu, Qing Cissy; Song, Wenqian; Lai, Dengwen; Zeng, Yi Arial

2017-08-03

Endothelial cells (ECs) are the fundamental building blocks of the vascular architecture and mediate vascular growth and remodeling to ensure proper vessel development and homeostasis. However, studies on endothelial lineage hierarchy remain elusive due to the lack of tools to gain access as well as to directly evaluate their behavior in vivo. To address this shortcoming, a new tissue model to study angiogenesis using the mammary fat pad has been developed. The mammary gland develops mostly in the postnatal stages, including puberty and pregnancy, during which robust epithelium proliferation is accompanied by extensive vascular remodeling. Mammary fat pads provide space, matrix, and rich angiogenic stimuli from the growing mammary epithelium. Furthermore, mammary fat pads are located outside the peritoneal cavity, making them an easily accessible grafting site for assessing the angiogenic potential of exogenous cells. This work also describes an efficient tracing approach using fluorescent reporter mice to specifically label the targeted population of vascular endothelial stem cells (VESCs) in vivo. This lineage tracing method, coupled with subsequent tissue whole-mount microscopy, enable the direct visualization of targeted cells and their descendants, through which the proliferation capability can be quantified and the differentiation commitment can be fate-mapped. Using these methods, a population of bipotent protein C receptor (Procr) expressing VESCs has recently been identified in multiple vascular systems. Procr + VESCs, giving rise to both new ECs and pericytes, actively contribute to angiogenesis during development, homeostasis, and injury repair. Overall, this manuscript describes a new mammary fat pad transplantation and in vivo lineage tracing techniques that can be used to evaluate the stem cell properties of VESCs.

Telemedicine Can Replace the Neurologist on a Mobile Stroke Unit.

PubMed

Wu, Tzu-Ching; Parker, Stephanie A; Jagolino, Amanda; Yamal, Jose-Miguel; Bowry, Ritvij; Thomas, Abraham; Yu, Amy; Grotta, James C

2017-02-01

The BEST-MSU study (Benefits of Stroke Treatment Delivered Using a Mobile Stroke Unit) is a comparative effectiveness trial in patients randomized to mobile stroke unit or standard management. A substudy tested interrater agreement for tissue-type plasminogen activator eligibility between a telemedicine vascular neurologist and onboard vascular neurologist. On scene, both the telemedicine vascular neurologist and onboard vascular neurologist independently evaluated the patient, documenting their tissue-type plasminogen activator treatment decision, National Institutes of Health Stroke Scale score, and computed tomographic interpretation. Agreement was determined using Cohen κ statistic. Telemedicine-related technical failures that impeded remote assessment were recorded. Simultaneous and independent telemedicine vascular neurologist and onboard vascular neurologist assessment was attempted in 174 patients. In 4 patients (2%), the telemedicine vascular neurologist could not make a decision because of technical problems. The telemedicine vascular neurologist agreed with the onboard vascular neurologist on 88% of evaluations (κ=0.73). Remote telemedicine vascular neurologist assessment is reliable and accurate, supporting either telemedicine vascular neurologist or onboard vascular neurologist assessment on our mobile stroke unit. URL: http://www.clinicaltrials.gov. Unique identifier: NCT02190500. © 2017 American Heart Association, Inc.

Vascular Access Procedures

MedlinePlus

... have a personal story about radiology? Share your patient story here Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. Related ...

Insertion side, body position and circuit life during continuous renal replacement therapy with femoral vein access.

PubMed

Kim, In Byung; Fealy, Nigel; Baldwin, Ian; Bellomo, Rinaldo

2011-01-01

Choice of insertion side and patient position during continuous renal replacement therapy (CRRT) with femoral vein vascular access may affect circuit life. We investigated if there is an association between choice of insertion side and body position and its changes and circuit life during CRRT with femoral vein access. We studied 50 patients receiving CRRT via femoral vein access with a sequential retrospective study in a tertiary intensive care unit. We defined two groups: patients with right or left femoral vein access. We then obtained information on age, gender, circuit life, total heparin dose, hemoglobin concentration and coagulation variables (platelet count, international normalized ratio, and activated partial thromboplastin time) and percentage of time each patient spent in the supine, left lying, right lying, and sitting position during treatment. We studied 341 circuits in 50 patients. Mean circuit life was 13.9 h. Of these circuits, 251 (73.6%) were treated with right femoral vein access. Mean circuit life in this group was significantly longer compared with left femoral vein access (15.0 ± 14.3 vs. 10.6 ± 7.4; p = 0.019). Percentage spent in a particular position during CRRT was not significantly different between two groups. On multivariable linear regression analysis, mean circuit life was significantly and positively correlated with right vascular access site (p = 0.03) and lower platelet count (p = 0.03), but not with patient position. Right-sided insertion but not time spent in a particular position significantly affects circuit life during CRRT with femoral vein access. Copyright © 2010 S. Karger AG, Basel.

Towards organ printing: engineering an intra-organ branched vascular tree.

PubMed

Visconti, Richard P; Kasyanov, Vladimir; Gentile, Carmine; Zhang, Jing; Markwald, Roger R; Mironov, Vladimir

2010-03-01

Effective vascularization of thick three-dimensional engineered tissue constructs is a problem in tissue engineering. As in native organs, a tissue-engineered intra-organ vascular tree must be comprised of a network of hierarchically branched vascular segments. Despite this requirement, current tissue-engineering efforts are still focused predominantly on engineering either large-diameter macrovessels or microvascular networks. We present the emerging concept of organ printing or robotic additive biofabrication of an intra-organ branched vascular tree, based on the ability of vascular tissue spheroids to undergo self-assembly. The feasibility and challenges of this robotic biofabrication approach to intra-organ vascularization for tissue engineering based on organ-printing technology using self-assembling vascular tissue spheroids including clinically relevantly vascular cell sources are analyzed. It is not possible to engineer 3D thick tissue or organ constructs without effective vascularization. An effective intra-organ vascular system cannot be built by the simple connection of large-diameter vessels and microvessels. Successful engineering of functional human organs suitable for surgical implantation will require concomitant engineering of a 'built in' intra-organ branched vascular system. Organ printing enables biofabrication of human organ constructs with a 'built in' intra-organ branched vascular tree.

Biomimicry, vascular restenosis and coronary stents.

PubMed

Schwartz, R S; van der Giessen, W J; Holmes, D R

1998-01-01

Biomimicry is in its earliest stages and is being considered in the realm of tissue engineering. If arterial implants are to limit neointimal thickening, purely passive structures cannot succeed. Bioactivity must be present, either by pharmacologic intervention or by fabricating a 'living stent' that contains active cellular material. As tissue engineering evolves, useful solutions will emerge from applying this knowledge directly to vascular biologic problems resulting from angioplasty, stenting, and vascular prosthesis research.

Phase I/II Trial of Epothilone Analog BMS-247550, Mitoxantrone, and Prednisone in HRPC Patients Previously Treated with Chemotherapy

DTIC Science & Technology

2006-07-01

McGaw AccuPro Pump Nitroglycerine IV Set (Catalog #V8333) • Clintec IV Fat Emulsion Set (Catalog #2C1105) Filter extension set (to be used with IV sets...menses; libido; vaginitis Vascular – thrombosis/ embolism ; vascular access complication Note: BMS-247550 in combination with other agents could cause...osteoporosis, vertebral compression fractures , pancreatitis, esophagitis, peptic ulcer, dermatologic disturbances, convulsions, vertigo, headache

Vascular access: the impact of ultrasonography

PubMed Central

de Almeida, Carlos Eduardo Saldanha

2016-01-01

ABSTRACT Vascular punctures are often necessary in critically ill patients. They are secure, but not free of complications. Ultrasonography enhances safety of the procedure by decreasing puncture attempts, complications and costs. This study reviews important publications and the puncture technique using ultrasound, bringing part of the experience of the intensive care unit of the Hospital Israelita Albert Einstein, São Paulo (SP), Brazil, and discussing issues that should be considered in future studies. PMID:28076607

Vascular Access Port Implantation and Serial Blood Sampling in a Gottingen Minipig (Sus scrofa domestica) Model of Acute Radiation Injury

PubMed Central

Moroni, Maria; Coolbaugh, Thea V; Mitchell, Jennifer M; Lombardini, Eric; Moccia, Krinon D; Shelton, Larry J; Nagy, Vitaly; Whitnall, Mark H

2011-01-01

Threats of nuclear and other radiologic exposures have been increasing, but no countermeasure for acute radiation syndrome has been approved by regulatory authorities. Because of their similarity to humans in regard to physiology and anatomy, we are characterizing Gottingen minipigs as a model to aid the development of radiation countermeasures. Irradiated minipigs exhibit immunosuppression, severe thrombocytopenia, vascular leakage, and acute inflammation. These complications render serial acquisition of blood samples problematic. Vascular access ports (VAP) facilitate serial sampling, but their use often is complicated by infections and fibrin deposition. We demonstrate here the successful use of VAP for multiple blood samplings in irradiated minipigs. Device design and limited postoperative prophylactic antimicrobial therapy before irradiation were key to obtaining serial sampling, reducing swelling, and eliminating infection and skin necrosis at the implantation site. Modifications of previous protocols included the use of polydioxanone sutures instead of silk; eliminating chronic port access; single-use, sterile, antireflux prefilled syringes for flushing; strict aseptic weekly maintenance of the device, and acclimating animals to reduce stress. VAP remained functional in 19 of 20 irradiated animals for as long as 3 mo. The remaining VAP failed due to a small leak in the catheter, leading to clot formation. VAP-related sepsis occurred in 2 minipigs. Blood sampling did not cause detectable stress in nonanesthetized sham-irradiated animals, according to leukograms and clinical signs. PMID:21333166

A numerical study of the effect of catheter angle on the blood flow characteristics in a graft during hemodialysis

NASA Astrophysics Data System (ADS)

Ryou, Hong Sun; Kim, Soyoon; Ro, Kyoungchul

2013-02-01

For patients with renal failure, renal replacement therapies are needed. Hemodialysis is a widely used renal replacement method to remove waste products. It is important to improve the patency rate of the vascular access for efficient dialysis. Since some complications such as an intimal hyperplasia are associated with the flow pattern, the hemodynamics in the vascular access must be considered to achieve a high patency rate. In addition, the blood flow from an artificial kidney affects the flow in the vascular access. Generally, the clinical techniques of hemodialysis such as the catheter angle or dialysis dose have been set up empirically. In this study, a numerical analysis is performed on the effect of the catheter angle on the flow in the graft. Blood is assumed to be a non-Newtonian fluid. According to the high average wall shear stress value, the leucocytes and platelets can be activated not only at the arterial anastomosis, but also at the bottom of the venous graft, when the catheter angle is not zero. For a catheter angle less than five degrees, there is a low shear and high oscillatory shear index region that appears at the venous graft and the venous anastomosis. Thus, a catheter angle less than five degrees should be avoided to prevent graft failure.

Current use of ultrasound for central vascular access in children and infants in the Nordic countries--a cross-sectional study.

PubMed

Olsen, Thomas C Risom; Rimstad, Ivan Jonassen; Tarpgaard, Mona; Holmberg, Svante; Hallas, Peter

2015-01-01

The use of ultrasound (US) guidance for central vascular access in children has been advocated as a safer approach compared to traditional landmark techniques. We therefore collected data on the current use of US for central vascular access in children and infants in the Nordic countries. A cross-sectional survey using an online questionnaire was distributed to one anaesthesiologist at every hospital in the Nordic countries; a total of 177 anaesthesiologists were contacted from July till August 2012. The use of US for placing central venous catheters (CVCs) seems widespread across the Nordic countries. Close to 80% of respondents were using it "almost always" or "frequently" across all paediatric age groups for internal jugular vein cannulation. US was least frequently used when catheterizing the subclavian vein. The two most common reasons given when not using US were lack of training followed by lack of equipment. We found no difference in the use of US between high-volume centres and low-volume centres. (High-volume centres placed paediatric CVCs at least weekly.). US was commonly used for cannulation of the internal jugular vein but infrequently for the subclavian vein. A lack of training seems to be a barrier for further increasing the use of US. Establishing standardized training programmes based on current evidence should alleviate this.

Vascular injury is associated with increased mortality in winter sports trauma.

PubMed

Eun, John C; Bronsert, Michael; Hansen, Kristine; Moulton, Steven L; Jazaeri, Omid; Nehler, Mark; Greenberg, Joshua I

2015-01-01

Trauma is the leading cause of injury and death for individuals aged 1-44 years. Up to 8% of the US population participates in winter sports, and although vascular injuries are uncommon in these activities, little is published in this area. We sought to identify the incidence, injury patterns, and outcomes of vascular injuries resulting from winter sports trauma. Patients with winter sports trauma and the subset with vascular injuries were identified by accessing the National Trauma Data Bank querying years 2007-2010. Patients with and without vascular injuries were then compared. Admission variables included transport time, emergency department hypotension (systolic blood pressure < 90), Glasgow Coma Scale ≤ 8, Injury Severity Score ≥ 25, fractures, solid organ injury, and vascular injury. Outcomes were analyzed and associations with vascular injuries were determined. A total of 2,298 patients were identified with winter sports-related trauma and 28 (1.2%) had associated vascular injuries. Overall, the top 3 injuries were head trauma (16.7%), thoracic vertebral fractures (5.5%), and lumbar vertebral fractures (5.1%). The most common associated vascular injures were to the popliteal artery (17.7%), splenic artery (14.7%), and brachial blood vessels (14.7%). In the entire cohort, 1 patient (0.04%) suffered an amputation and 15 patients (0.7%) died. There were no amputations in the vascular injury group. Mortality was 0.6% in patients without a vascular injury compared with 7.1% of those with a vascular injury (P = 0.01). Although vascular injury is an uncommon associated finding in winter sports trauma, it is associated with a significant increase in mortality. These findings highlight the need for rapid identification of traumatic vascular injuries, which predicts worse overall outcomes in this patient population. Copyright © 2015 Elsevier Inc. All rights reserved.

EZ-IO(®) intraosseous device implementation in German Helicopter Emergency Medical Service.

PubMed

Helm, Matthias; Haunstein, Benedikt; Schlechtriemen, Thomas; Ruppert, Matthias; Lampl, Lorenz; Gäßler, Michael

2015-03-01

Intraosseous access (IO) is a rapid and safe alternative when peripheral venous access is difficult. Our aim was to summarize the first three years experience with the use of a semi-automatic IO device (EZ-IO(®)) in German Helicopter Emergency Medical Service (HEMS). Included were all patients during study period (January 2009-December 2011) requiring an IO access performed by HEMS team. Outcome variables were IO rate, IO insertion success rates, site of IO access, type of EZ-IO(®) needle set used, strategy of vascular access, procedure related problems and operator's satisfaction. IO rate was 0.3% (348/120.923). Overall success rate was 99.6% with a first attempt success rate of 85.9%; there was only one failure (0.4%). There were three insertion sites: proximal tibia (87.2%), distal tibia (7.5%) and proximal humerus (5.3%). Within total study group IO was predominantly the second-line strategy (39% vs. 61%, p<0.001), but in children<7 years, in trauma cases and in cardiac arrest IO was more often first-line strategy (64% vs. 28%, p<0.001; 48% vs. 34%, p<0.032; 50% vs. 29%, p<0.002 respectively). Patients with IO access were significantly younger (41.7±28.7 vs. 56.5±24.4 years; p<0.001), more often male (63.2% vs. 57.7%; p=0.037), included more trauma cases (37.3% vs. 30.0%; p=0.003) and more often patients with a NACA-Score≥5 rating (77.0% vs. 18.6%; p<0.001). Patients who required IO access generally presented with more severely compromised vital signs associated with the need for more invasive resuscitation actions such as intubation, chest drains, CPR and defibrillation. In 93% EZ-IO(®) needle set handling was rated "good". Problems were reported in 1.6% (needle dislocation 0.8%, needle bending 0.4% and parafusion 0.4%). The IO route was generally used in the most critically ill of patients. Our relatively low rate of usage would indicate that this would be compatible with the recommendations of established guidelines. The EZ-IO(®) intraosseous device proved feasible with a high success rate in adult and pediatric emergency patients in HEMS. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Stroke Treatments

MedlinePlus

... to the brain. It's the most common type, accounting for 87% of all strokes. The treatment goal ... that the surgeon gains access via the vascular system, making it less invasive than conventional surgical treatment. ...

UK Renal Registry 16th annual report: chapter 14 2012 multisite dialysis access audit in England, Northern Ireland and Wales and 2011 PD one year follow-up: national and centre-specific analyses.

PubMed

Briggs, Victoria; Pitcher, David; Shaw, Catriona; Fluck, Richard; Wilkie, Martin

2013-01-01

Dialysis access should be timely, minimise complications and maintain functionality. Good functional access is required for renal replacement therapy (RRT) to be successful. The aim of the combined vascular and peritoneal dialysis access audit was to examine practice patterns with respect to dialysis access and highlight variations in practice between renal centres. The UK Renal Registry collected centre-specific information on vascular and peritoneal access outcome measures including patient demographics, dialysis access type (at start of dialysis and three months after start of dialysis), surgical assessment and access functionality. The combined access audit covered incident haemodialysis (HD) and peritoneal dialysis (PD) patients in 2012 from England, Northern Ireland and Wales. Centres who had reported data on incident PD patients for the previous audit in 2011 were additionally asked to provide one year follow up data for this group. Fifty-one centres in England, Wales and Northern Ireland (representing 82% of all centres) returned data on first access from 3,720 incident HD patients and 1,018 incident PD patients. A strong relationship was seen between surgical assessment and the likelihood of starting HD with an arteriovenous fistula (AVF). Type of first access was related to the length of time known to renal services with higher numbers of AVFs and PD catheters used in patients known to renal services for at least one year. Three month and one year outcomes of HD and PD access were poorly reported. This audit provides information on important patient related outcome measures with the potential to lead to an improvement in access provision. This represents an important advance, however data collection remains suboptimal. There is wide practice variation across the England, Wales and Northern Ireland in provision of both HD and PD access which requires further exploration. © 2014 S. Karger AG, Basel.

Peripherally inserted central catheter - insertion

MedlinePlus

... ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 26. Smith SF, Duell DJ, Martin BC, Gonzalez L, Aebersold M. Central vascular access devices. In: Smith SF, Duell DJ, Martin BC, Gonzalez L, Aebersold ...

Reanalyzing the "far medial" (transcondylar-transtubercular) approach based on three anatomical vectors: the ventral posterolateral corridor.

PubMed

Chakravarthi, Srikant; Monroy-Sosa, Alejandro; Gonen, Lior; Fukui, Melanie; Rovin, Richard; Kojis, Nathaniel; Lindsay, Mark; Khalili, Sammy; Celix, Juanita; Corsten, Martin; Kassam, Amin B

2018-06-01

Endoscopic endonasal access to the jugular foramen and occipital condyle - the transcondylar-transtubercular approach - is anatomically complex and requires detailed knowledge of the relative position of critical neurovascular structures, in order to avoid inadvertent injury and resultant complications. However, access to this region can be confusing as the orientation and relationships of osseous, vascular, and neural structures are very much different from traditional dorsal approaches. This review aims at providing an organizational construct for a more understandable framework in accessing the transcondylar-transtubercular window. The region can be conceptualized using a three-vector coordinate system: vector 1 represents a dorsal or ventral corridor, vector 2 represents the outer and inner circumferential anatomical limits; in an "onion-skin" fashion, key osseous, vascular, and neural landmarks are organized based on a 360-degree skull base model, and vector 3 represents the final core or target of the surgical corridor. The creation of an organized "global-positioning system" may better guide the surgeon in accessing the far-medial transcondylar-transtubercular region, and related pathologies, and help understand the surgical limits to the occipital condyle and jugular foramen - the ventral posterolateral corridor - via the endoscopic endonasal approach.

Clinicopathological correlation of psychosis and brain vascular changes in Alzheimer's disease.

PubMed

Ting, Simon Kang Seng; Hao, Ying; Chia, Pei Shi; Tan, Eng-King; Hameed, Shahul

2016-02-12

Psychosis is common in Alzheimer's disease (AD). However, studies on neuropathology in vascular etiology contributing to psychosis in AD is lacking to date. The aim of this study was to investigate neuropathological vascular related changes in Alzheimer's disease with psychosis. Data of patients with AD from the National Alzheimer's Coordinating Center between 2005 to September 2013 was accessed and reviewed. Presence of psychosis was determined based on Neuropsychiatric Inventory Questionnaire taken from the last visit within one year prior to death, and patients were divided into psychosis positive and negative group. Comparison of clinical details and neuropathological vascular changes between the groups was performed using Wilcoxon rank sum test and Chi-square/ Fisher's exact test. Significant variables were further included in a multivariate logistic model. Overall, 145 patients was included. Of these, 50 patients were psychosis positive. Presence of one or more cortical microinfarcts and moderate to severe arteriosclerosis was found to be positively associated with psychosis. Our results suggest vascular changes correlate with psychosis in Alzheimer's disease.

The use of intraosseous infusions in the operating room.

PubMed

Joseph, Gayatri; Tobias, Joseph D

2008-09-01

The use of an intraosseous (IO) infusion during the anesthetic care of an 8-month-old, 5.4-kg infant with cyanotic congenital heart disease (CHD) is presented. Previous vascular access had resulted in thrombotic occlusion of the upper and lower venous systems. When intravenous access could not be achieved, an IO needle was placed and IO access was used during the surgical procedure. The role of the IO route in the perioperative period is discussed and its adverse effect profile is reviewed.

The diagnostic value of finger systolic blood pressure and cold-provocation testing for the vascular component of hand-arm vibration syndrome in health surveillance.

PubMed

Poole, K; Elms, J; Mason, H J

2004-12-01

Hand-arm vibration syndrome (HAVS) is a complex condition with vascular, sensorineural and musculoskeletal components. A number of quantitative tests have been used for assisting in the diagnosis of HAVS and grading disease severity. To investigate and compare the diagnostic value of finger systolic blood pressure (FSBP) and rewarming of finger skin temperature (FST) following cold-provocation testing, in the assessment of vascular HAVS. Twenty-four individuals with vascular HAVS (Stockholm Workshop stage 2 or 3V) and 22 control subjects underwent FSBP measurements at 30, 15 and 10 degrees C and monitoring of FST following immersion of the hands in water at 15 degrees C for 5 min. There was a significant reduction in median FSBP% in the vascular HAVS group in the change in FSBP from 30 to 15 degrees C adjusted for brachial blood pressure (FSBPC%). There was no difference in the median time for FST to rewarm by 4 degrees C between HAVS cases and controls. The sensitivity and specificity of FSBP to discriminate between the groups varied between 44 and 61% and 91 and 95%, respectively. The sensitivity and specificity for the time for FST to rewarm by 4 degrees C were 71 and 77%. There is little evidence that the described form of finger rewarming after cold-provocation testing is a useful diagnostic test for vascular HAVS, although it may have some moderate influence in ruling out vascular problems. Based on our data, the FSBP may also have limited use in confirming a positive diagnosis of vibration-induced vascular problems. The higher specificity of the FSBP test suggests it may have some value in ruling out the vascular component of HAVS. The data from this study do not confirm the diagnostic power of FSBP for the vascular component of HAVS reported by a few other investigators.

Towards organ printing: engineering an intra-organ branched vascular tree

PubMed Central

Visconti, Richard P; Kasyanov, Vladimir; Gentile, Carmine; Zhang, Jing; Markwald, Roger R; Mironov, Vladimir

2013-01-01

Importance of the field Effective vascularization of thick three-dimensional engineered tissue constructs is a problem in tissue engineering. As in native organs, a tissue-engineered intra-organ vascular tree must be comprised of a network of hierarchically branched vascular segments. Despite this requirement, current tissue-engineering efforts are still focused predominantly on engineering either large-diameter macrovessels or microvascular networks. Areas covered in this review We present the emerging concept of organ printing or robotic additive biofabrication of an intra-organ branched vascular tree, based on the ability of vascular tissue spheroids to undergo self-assembly. What the reader will gain The feasibility and challenges of this robotic biofabrication approach to intra-organ vascularization for tissue engineering based on organ-printing technology using self-assembling vascular tissue spheroids including clinically relevantly vascular cell sources are analyzed. Take home message It is not possible to engineer 3D thick tissue or organ constructs without effective vascularization. An effective intra-organ vascular system cannot be built by the simple connection of large-diameter vessels and microvessels. Successful engineering of functional human organs suitable for surgical implantation will require concomitant engineering of a ‘built in’ intra-organ branched vascular system. Organ printing enables biofabrication of human organ constructs with a ‘built in’ intra-organ branched vascular tree. PMID:20132061

Your Dialysis Care Team

MedlinePlus

... A to Z Health Guide Your Dialysis Care Team Tweet Share Print Email Good health care is ... dialyzers (artificial kidneys) for reuse. Vascular Access Care Team If you are a hemodialysis patient, another group ...

A call for formal telemedicine training during stroke fellowship

PubMed Central

Jia, Judy; Gildersleeve, Kasey; Ankrom, Christy; Cai, Chunyan; Rahbar, Mohammad; Savitz, Sean I.; Wu, Tzu-Ching

2016-01-01

During the 20 years since US Food and Drug Administration approval of IV tissue plasminogen activator for acute ischemic stroke, vascular neurology consultation via telemedicine has contributed to an increased frequency of IV tissue plasminogen activator administration and broadened geographic access to the drug. Nevertheless, a growing demand for acute stroke coverage persists, with the greatest disparity found in rural communities underserved by neurologists. To provide efficient and consistent acute care, formal training in telemedicine during neurovascular fellowship is warranted. Herein, we describe our experiences incorporating telestroke into the vascular neurology fellowship curriculum and propose recommendations on integrating formal telemedicine training into the Accreditation Council for Graduate Medical Education vascular neurology fellowship. PMID:27016522

A call for formal telemedicine training during stroke fellowship.

PubMed

Jagolino, Amanda L; Jia, Judy; Gildersleeve, Kasey; Ankrom, Christy; Cai, Chunyan; Rahbar, Mohammad; Savitz, Sean I; Wu, Tzu-Ching

2016-05-10

During the 20 years since US Food and Drug Administration approval of IV tissue plasminogen activator for acute ischemic stroke, vascular neurology consultation via telemedicine has contributed to an increased frequency of IV tissue plasminogen activator administration and broadened geographic access to the drug. Nevertheless, a growing demand for acute stroke coverage persists, with the greatest disparity found in rural communities underserved by neurologists. To provide efficient and consistent acute care, formal training in telemedicine during neurovascular fellowship is warranted. Herein, we describe our experiences incorporating telestroke into the vascular neurology fellowship curriculum and propose recommendations on integrating formal telemedicine training into the Accreditation Council for Graduate Medical Education vascular neurology fellowship. © 2016 American Academy of Neurology.

A novel narrow profile articulating powered vascular stapler provides superior access and haemostasis equivalent to conventional devices†

PubMed Central

Ng, Calvin S.H.; Pickens, Allan; Siegel, Julianne M.; Clymer, Jeffrey W.; Cummings, John F.

2016-01-01

OBJECTIVE Current endoscopic transection devices are not optimized to meet the unique challenges posed by the task of vessel transection in difficult-to-access locations within the pleural cavity. The ECHELON FLEX™ powered vascular stapler (PVS) has been designed with four rows of staples instead of six, to decrease its size and enable more precise placement on fragile pulmonary vessels, using a narrower anvil than other commercially available transecting devices. This study was performed to determine whether the reduced number of staple rows affects haemostasis, and to assess surgeons' initial impression of the smaller stapler during in vivo usage. METHODS The new four-row stapler was compared with commercially available six-row articulating staplers via expert graders using a validated scale of haemostasis in vivo after application on porcine gastroepiploic pedicles and other thin- and thick-walled vessels. The new stapler was then compared with current products by practising thoracic surgeons (n = 27) during in vivo usage of simulated pulmonary procedures in a porcine model. The surgeons were also surveyed on the key attributes of the four-row stapler in relation to the six-row predicates. RESULTS Haemostasis evaluated on an ordered scale was clinically equivalent between the test and predicate staplers, and was deemed acceptable for all thin- and thick-vascular tissue applications. Surgeons found no difference in haemostasis between the four- and six-row staplers (P = 0.486), and judged the four-row stapler superior in terms of access, reduced need for dissection, reduced stress of surgeon and precise control (P < 0.001 for all). CONCLUSIONS The new ECHELON FLEX™ PVS provides haemostasis equivalent to six-row staplers. With a smaller anvil, narrower shaft and wider angle of articulation, the PVS demonstrated improved access capability for pulmonary vessel procedures. PMID:26464450

Pre-End-Stage Renal Disease Care and Early Survival among Incident Dialysis Patients in the US Military Health System.

PubMed

Nee, Robert; Fisher, Evan; Yuan, Christina M; Agodoa, Lawrence Y; Abbott, Kevin C

2017-01-01

Previous reports showed an increased early mortality after chronic dialysis initiation among the end-stage renal disease (ESRD) population. We hypothesized that ESRD patients in the Military Health System (MHS) would have greater access to pre-ESRD care and hence better survival rates during this early high-risk period. In this retrospective cohort study, using the US Renal Data System database, we identified 1,256,640 patients initiated on chronic dialysis from January 2, 2004 through December 31, 2014, from which a bootstrap sample of 3,984 non-MHS incident dialysis patients were compared with 996 MHS patients. We assessed care by a nephrologist and dietitian, erythropoietin administration, and vascular access use at dialysis initiation as well as all-cause mortality as outcome variables. MHS patients were significantly more likely to have had pre-ESRD nephrology care (adjusted OR [aOR] 2.9; 95% CI 2.3-3.7) and arteriovenous fistula used at dialysis initiation (aOR 2.2; 95% CI 1.7-2.7). Crude mortality rates peaked between the 4th and the 8th week for both cohorts but were reduced among MHS patients. The baseline adjusted Cox model showed significantly lower death rates among MHS vs. non-MHS patients at 6, 9, and 12 months. This survival advantage among MHS patients was attenuated after further adjustment for pre-ESRD nephrology care and dialysis vascular access. MHS patients had improved survival within the first 12 months compared to the general ESRD population, which may be explained in part by differences in pre-ESRD nephrology care and vascular access types. © 2017 S. Karger AG, Basel.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Powell, Steven, E-mail: Steven.Powell@rlbuht.nhs.uk; Narlawar, Ranjeet; Odetoyinbo, Tolulola

The Amplatzer Vascular Plug Type II (AVP II) has proven effective in the therapeutic embolization of various vascular lesions. It benefits from very rapid occlusion of the target lesion and can be deployed, retrieved, and redeployed if required. There is no literature available on use of the AVP II in the maintenance, closure, and management of complicated arteriovenous access in hemodialysis patients. In this series, we present our clinical experience with the use of the AVP II for embolization of problematic hemodialysis access. The AVP II is a self-expandable Nitinol wire-mesh device. Mounted on a delivery wire it has themore » capability to be deployed, recaptured, and redeployed. In total seven patients (four males: one diabetic, all nonsmokers), with ages ranging from 44 to 81 years (mean, 63 years), were treated between July 2008 and January 2009. One patient had not started dialysis. The remaining six patients had varied histories, with the time on hemodialysis ranging from 1 to 21 years. Retrospective review of clinical notes revealed patient demographics, type of access, device size, deployment site, and outcomes. Indications for embolization included steal syndrome (one patient), high-flow tributaries (two patients), and limb swelling (four patients). All patients had clinical and sonographical follow-up to 3 months. Surgical ligation had either failed, was considered a contraindication due to concerns regarding wound healing, or was considered difficult due to complex venous anatomy. Only one device was used in each patient, ranging from 6 to 16 mm in diameter. Immediate technical success was seen in 100%. All these patients were followed up clinically in the vascular access radiology clinic at 4 weeks and 3 months. Occlusion of the treated vessel and resolution of symptoms were reconfirmed in 100% of cases at 3 months. It was also noted whether patients were having successful dialysis, if required. There were no complications. Average procedural time was 19 min. We conclude that the AVP II is an efficient, safe, and technically simple occlusion device for use in arteriovenous access.« less

Successful removal of embolized chemoport catheter within the heart and pericardium: 3 case reports

PubMed Central

Yoon, Shin-Eui

2017-01-01

Central venous access devices are routinely used in patients with cancer. Although rare, catheter transaction with subsequent embolization is one of the major complications of intra-vascular devices. We describe two patients with embolized chemoport catheters within the heart that were successfully removed percutaneously using a goose-neck snare technique. We also describe a third patient with a fractured intra-vascular catheter in the pericardium removed by pericardiotomy, which can be the first case of the kind. PMID:28932593

Impact of Hemodialysis Catheter Dysfunction on Dialysis and Other Medical Services: An Observational Cohort Study

PubMed Central

Griffiths, Robert I.; Newsome, Britt B.; Leung, Grace; Block, Geoffrey A.; Herbert, Robert J.; Danese, Mark D.

2012-01-01

Practice guidelines define hemodialysis catheter dysfunction as blood flow rate (BFR) <300 mL/min. We conducted a study using data from DaVita and the United States Renal Data System to evaluate the impact of catheter dysfunction on dialysis and other medical services. Patients were included if they had ≥8 consecutive weeks of catheter dialysis between 8/2004 and 12/2006. Actual BFR <300 mL/min despite planned BFR ≥300 mL/min was used to define catheter dysfunction during each dialysis session. Among 9,707 patients, the average age was 62,53% were female, and 40% were black. The median duration of catheter dialysis was 190 days, and the cohort accounted for 1,075,701 catheter dialysis sessions. There were 70,361 sessions with catheter dysfunction, and 6,33 1 (65.2%) patients had at least one session with catheter dysfunction. In multivariate repeated measures analysis, catheter dysfunction was associated with increased odds of missing a dialysis session due to access problems (Odds ratio [OR] 2.50; P < 0.001), having an access-related procedure (OR 2.10; P < 0.001), and being hospitalized (OR 1.10; P = 0.001). Catheter dysfunction defined according to NKF vascular access guidelines results in disruptions of dialysis treatment and increased use of other medical services. PMID:22518313

Totally implantable vascular access device (TIVAD) placement: a modified technique that takes post-procedure aesthetic aspects into account.

PubMed

Liberale, Gabriel

2017-04-01

Major progress has been made in breast cancer reconstruction surgery. The standard technique for totally implanted vascular access device (TIVAD) implantation generally requires an incision for port insertion on the anterior part of the thorax that leaves a scar in the middle of the neckline in patients who have undergone mastectomy with complex breast reconstruction. The aim of this technical note is to report our revised surgical technique for TIVAD placement. In patients with breast cancer, we take a lateralized approach, performing an oblique incision on the lowest part of the deltopectoral groove. This allows us to introduce the port and to place it on the anterolateral part of the thorax, thus avoiding an unaesthetic scar on the anterior part of the thorax. Our modified technique for TIVAD implantation is described.

Vascular access for hemodialysis: creation, functioning, and complications (data of the Hospital of Kaunas University of Medicine).

PubMed

Kybartienė, Sondra; Skarupskienė, Inga; Ziginskienė, Edita; Kuzminskis, Vytautas

2010-01-01

There are no data about arteriovenous fistulas (AVF) formation, survival, and complications rate in patients with end-stage renal failure in Lithuania. We analyzed the data of patients (N=272) with end-stage renal failure, dialyzed at the Hospital of Kaunas University of Medicine from January 1, 2000, until March 30, 2010, and identified 368 cases of AVF creation. The patients were divided into two groups: group 1 included the patients with an AVF that functioned for <15 months (n=138) and group 2 included patients with an AVF that functioned for ≥15 months (n=171). Less than half (47%) of the patients started planned hemodialysis and 51% of the patients started hemodialysis urgently. The mean time of AVF functioning was 15.43±8.67 months. Age, gender, the kidney disease, and time of AVF maturation had no influence on AVF functioning time. AVFs of the patients who started planned hemodialysis functioned longer as compared to AVFs of the patients who started hemodialysis urgently (P<0.05). Hospitalization time of the patients who started hemodialysis urgently was longer as compared that of the patients who had a matured AVF (37.63±20.55 days vs. 16.54±9.43 days). The first vascular access had better survival than repeated access. AVF survival in patients with ischemic brain vascular disease was worse than in patients without this comorbidity.

Surveillance of hemodialysis vascular access with ultrasound vector flow imaging

NASA Astrophysics Data System (ADS)

Brandt, Andreas H.; Olesen, Jacob B.; Hansen, Kristoffer L.; Rix, Marianne; Jensen, Jørgen A.; Nielsen, Michael B.

2015-03-01

The aim of this study was prospectively to monitor the volume flow in patients with arteriovenous fistula (AVF) with the angle independent ultrasound technique Vector Flow Imaging (VFI). Volume flow values were compared with Ultrasound dilution technique (UDT). Hemodialysis patients need a well-functioning vascular access with as few complications as possible and preferred vascular access is an AVF. Dysfunction due to stenosis is a common complication, and regular monitoring of volume flow is recommended to preserve AVF patency. UDT is considered the gold standard for volume flow surveillance, but VFI has proven to be more precise, when performing single repeated instantaneous measurements. Three patients with AVF were monitored with UDT and VFI monthly for five months. A commercial ultrasound scanner with a 9 MHz linear array transducer with integrated VFI was used to obtain data. UDT values were obtained with Transonic HD03 Flow-QC Hemodialysis Monitor. Three independent measurements at each scan session were obtained with UDT and VFI each month. Average deviation of volume flow between UDT and VFI was 25.7 % (Cl: 16.7% to 34.7%) (p= 0.73). The standard deviation for all patients, calculated from the mean variance of each individual scan sessions, was 199.8 ml/min for UDT and 47.6 ml/min for VFI (p = 0.002). VFI volume flow values were not significantly different from the corresponding estimates obtained using UDT, and VFI measurements were more precise than UDT. The study indicates that VFI can be used for surveillance of volume flow.

Utilizing the Foreign Body Response to Grow Tissue Engineered Blood Vessels in Vivo.

PubMed

Geelhoed, Wouter J; Moroni, Lorenzo; Rotmans, Joris I

2017-04-01

It is well known that the number of patients requiring a vascular grafts for use as vessel replacement in cardiovascular diseases, or as vascular access site for hemodialysis is ever increasing. The development of tissue engineered blood vessels (TEBV's) is a promising method to meet this increasing demand vascular grafts, without having to rely on poorly performing synthetic options such as polytetrafluoroethylene (PTFE) or Dacron. The generation of in vivo TEBV's involves utilizing the host reaction to an implanted biomaterial for the generation of completely autologous tissues. Essentially this approach to the development of TEBV's makes use of the foreign body response to biomaterials for the construction of the entire vascular replacement tissue within the patient's own body. In this review we will discuss the method of developing in vivo TEBV's, and debate the approaches of several research groups that have implemented this method.

The chicken chorioallantoic membrane model in biology, medicine and bioengineering

PubMed Central

Nowak-Sliwinska, Patrycja; Segura, Tatiana; Iruela-Arispe, M. Luisa

2015-01-01

The chicken chorioallantoic membrane (CAM) is a simple, highly vascularized extraembryonic membrane, which performs multiple functions during embryonic development, including but not restricted to gas exchange. Over the last two decades, interest in the CAM as a robust experimental platform to study blood vessels has been shared by specialists working in bioengineering, development, morphology, biochemistry, transplant biology, cancer research and drug development. The tissue composition and accessibility of the CAM for experimental manipulation, makes it an attractive preclinical in vivo model for drug screening and / or for studies of vascular growth. In this article we provide a detailed review of the use of the CAM to study vascular biology and response of blood vessels to a variety of agonists. We also present distinct cultivation protocols discussing their advantages and limitations and provide a summarized update on the use of the CAM in vascular imaging, drug delivery, pharmacokinetics and toxicology. PMID:25138280

Validation of computational fluid dynamics-based analysis to evaluate hemodynamic significance of access stenosis.

PubMed

Hoganson, David M; Hinkel, Cameron J; Chen, Xiaomin; Agarwal, Ramesh K; Shenoy, Surendra

2014-01-01

Stenosis in a vascular access circuit is the predominant cause of access dysfunction. Hemodynamic significance of a stenosis identified by angiography in an access circuit is uncertain. This study utilizes computational fluid dynamics (CFD) to model flow through arteriovenous fistula to predict the functional significance of stenosis in vascular access circuits. Three-dimensional models of fistulas were created with a range of clinically relevant stenoses using SolidWorks. Stenoses diameters ranged from 1.0 to 3.0 mm and lengths from 5 to 60 mm within a fistula diameter of 7 mm. CFD analyses were performed using a blood model over a range of blood pressures. Eight patient-specific stenoses were also modeled and analyzed with CFD and the resulting blood flow calculations were validated by comparison with brachial artery flow measured by duplex ultrasound. Predicted flow rates were derived from CFD analysis of a range of stenoses. These stenoses were modeled by CFD and correlated with the ultrasound measured flow rate through the fistula of eight patients. The calculated flow rate using CFD correlated within 20% of ultrasound measured flow for five of eight patients. The mean difference was 17.2% (ranged from 1.3% to 30.1%). CFD analysis-generated flow rate tables provide valuable information to assess the functional significance of stenosis detected during imaging studies. The CFD study can help in determining the clinical relevance of a stenosis in access dysfunction and guide the need for intervention.

Superior Patency of Upper Arm Arteriovenous Fistulae in High Risk Patients

PubMed Central

Chiulli, Larissa C; Vasilas, Penny; Dardik, Alan

2011-01-01

Background Despite an increased propensity to primary failure in forearm arteriovenous fistulae compared to upper arm fistulae, forearm fistulae remain the preferred primary access type for chronic hemodialysis patients. In a high risk patient population with multiple medical comorbidities associated with requirement for intravenous access we compared the rates of access failure in forearm and upper arm fistulae. Materials and Methods The records of all patients having primary native arteriovenous fistulae placed between 2004 and 2009 at the VA Connecticut Healthcare system were reviewed (n=118). Primary and secondary patency of upper arm and forearm fistulae were evaluated using Kaplan-Meier survival analysis. The effects of medical comorbidities on access patency were analyzed with Cox regression. Results The median time to primary failure of the vascular access was 0.288 years in the forearm group compared to 0.940 years in the upper arm group (p=0.028). Secondary patency was 52% at 4.9 years in upper arm fistulae compared to 52% at 1.1 years in the forearm group (p=0.036). There was no significant effect of patient comorbidities on fistula failure; however, there was a trend toward upper arm surgical site as a protective factor for primary fistula patency (Hazard Ratio=0.573, p=0.076). Conclusions In veterans needing hemodialysis, a high risk population with extensive comorbid factors often requiring intravascular access, upper arm fistulae are not only a viable option for primary vascular access, but are likely to be a superior option to classic forearm fistulae. PMID:21571318

Nitroglycerin-induced changes in facial skin temperature: 'cold nose' as a predictor of headache?

PubMed

Zaproudina, Nina; Närhi, Matti; Lipponen, Jukka A; Tarvainen, Mika P; Karjalainen, Pasi A; Karhu, Jari; Airaksinen, Olavi; Giniatullin, Rashid

2013-11-01

Nitroglycerin (NTG) often induces headaches when used to treat cardiac diseases. Such property of NTG has been widely used in modelling of migraine-like headaches. However, background reasons, predisposing to the development of NTG-headache, are less studied. The main aim of our study was to find, using NTG model, easily accessible markers of the vascular changes associated with headache. Because changes in the blood flow alter the local skin temperature (Tsk), we studied the relationship between the regional changes in the facial Tsk and NTG-induced headaches. Tsk was measured with infrared thermography in 11 healthy women during 3 h after sublingual NTG administration. NTG caused headache in five women, and four of them were the first-degree relatives of migraine patients. Notably, before NTG administration, subjects in the headache group had lower Tsk values, especially in the nose area, than women in the pain-free group (n = 6). NTG-induced headache was associated with a long-lasting increase of Tsk over the baseline. In sharp contrast, in the pain-free group, the Tsk reduced and returned rapidly to the baseline. Thus, the low baseline level and greater increase of regional Tsk correlated with the incidence of headache that supports a role of greater vascular changes in headache happening on the basis of the dissimilarities in vascular tone. An easily accessible phenomenon of 'cold nose' may indicate background vascular dysfunctions in individuals with predisposition to headache. Facial infrared thermography, coupled with NTG administration, suggests a novel temporally controlled approach for non-invasive investigation of vascular processes accompanying headaches. © 2013 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

Arterioarterial Prosthetic Loop as an Alternative Approach for Hemodialysis Access.

PubMed

Lei, Wenhui; Ji, Jiansong; Wang, Jian; Jin, Lie; Zou, Hai

2015-10-01

In the present study, we performed an arterioarterial prosthetic loop (AAPL) between the femoral artery and deep femoral artery as a new access in patients who did not have adequate vascular conditions for creating an arteriovenous fistula or graft.Between April 2005 and June 2014, 18 patients received AAPL as a vascular access. During the procedure, a polytetrafluoroethylene graft was anastomosed to the femoral artery and deep femoral artery and looped on the thigh. We assessed the reliability and safety of AAPLs by analyzing complication, primary and secondary patency rates, and postoperative blood flow.Eighteen patients (median age, 66 years; range, 43-96 years) underwent AAPL access placement under the general or local anesthesia. All patients were followed up for 3 to 38 months (mean, 24 months). Primary and secondary patency rates at 6 months were 94.5% and 88.8%, respectively, and at 3 years were 61% and 72%, respectively. After operation, one patient had infection, and another one had fat necrosis at the surgical incision site. To maintain the AAPL function, 5 surgical procedures in 4 grafts, including revision, thrombectomy, excision, and repair for bleeding were performed. More than 5000 hemodialyses were performed efficiently in our center.Our study shows that AAPL loop is an unusual but effective and safe procedure that may be a good alternative for the patients who do not allow the conventional hemodialysis access.

Vascular alterations underlie developmental problems manifested in cloned cattle before or after birth.

PubMed

Maiorka, Paulo Cesar; Favaron, Phelipe Oliveira; Mess, Andrea Maria; dos Santos, Caio Rodrigues; Alberto, Miryan Lanca; Meirelles, Flavio Vieira; Miglino, Maria Angelica

2015-01-01

Although assisted reproductive techniques are commonly applied in humans and animals, they are frequently associated with major developmental deficits and reduced viability. To explore abnormalities associated with cloning or nuclear transfer (NT) as the most invasive of these methods, we used a bovine model to characterize abnormalities. Detailed necropsy examinations were done on 13 calves that died soon after birth; in addition, we included data from embryos and fetuses (produced by NT) that terminated prematurely. Bovine clones that survived until the neonatal period differed quantitatively and qualitatively from in-vivo-derived cattle. Although alterations affected a variety of organs (e.g. heart, lung and liver), there was a clear association with abberant vascular developmental during the early intrauterine phase. Therefore, we concluded that vascular problems were key alterations induced by cloning (presumably via epigenetic modifications).

Vascular Alterations Underlie Developmental Problems Manifested in Cloned Cattle before or after Birth

PubMed Central

Favaron, Phelipe Oliveira; dos Santos, Caio Rodrigues; Alberto, Miryan Lanca; Meirelles, Flavio Vieira; Miglino, Maria Angelica

2015-01-01

Although assisted reproductive techniques are commonly applied in humans and animals, they are frequently associated with major developmental deficits and reduced viability. To explore abnormalities associated with cloning or nuclear transfer (NT) as the most invasive of these methods, we used a bovine model to characterize abnormalities. Detailed necropsy examinations were done on 13 calves that died soon after birth; in addition, we included data from embryos and fetuses (produced by NT) that terminated prematurely. Bovine clones that survived until the neonatal period differed quantitatively and qualitatively from in-vivo-derived cattle. Although alterations affected a variety of organs (e.g. heart, lung and liver), there was a clear association with abberant vascular developmental during the early intrauterine phase. Therefore, we concluded that vascular problems were key alterations induced by cloning (presumably via epigenetic modifications). PMID:25584533

Endoscopic Ultrasound-Guided Vascular Therapy: The Present and the Future

PubMed Central

Hall, Philip S.J.; Teshima, Christopher; May, Gary R.; Mosko, Jeffrey D.

2017-01-01

Endoscopic ultrasound (EUS) offers access to many intra-abdominal vessels that until now have only been accessible to the surgeon and interventional radiologist. In addition to assisting with diagnostics, this unique access offers the potential for therapeutic intervention for a host of indications. To date, this has had the most clinical impact in the treatment of gastroesophageal varices, with EUS-guided coil and glue application growing in use worldwide. Although randomised controlled trial data is lacking, we discuss the growing body of literature behind EUS-guided therapy in the management of varices. EUS has also been used in specialized centres to assist in non-variceal gastrointestinal bleeding. The treatment of bleeding from Dieulafoy lesions, tumours and pancreatic pseudoaneurysms has all been described. The potential applications of EUS have also extended to the placement of portal vein stents and porto-systemic shunts in animal models. As medicine continues to move to increasingly less invasive interventions, EUS-guided therapies offer substantial promise for the safe and effective delivery of targeted treatment for a widening array of vascular disorders. PMID:28391673

Vascularized bone graft for scaphoid nonunions.

PubMed

Mih, Alexander D

2004-09-01

Scaphoid fracture nonunion remains a challenging problem that may persist despite traditional methods of bone grafting and internal fixation. The alteration of wrist mechanics created by nonunion as well as the development of avascular necrosis leads to degenerative change of the radiocarpal joint accompanied by loss of motion and pain. The use of a vascularized bone graft has the theoretical benefit of increased blood flow that exceeds that of nonvascularized grafts. Numerous sources of vascularized bone graft have been described, including those from remote sites as well as from the carpus and distal radius. Knowledge of the blood supply to the distal radius has allowed for development of several vascularized bone graft harvest sites. The results of vascularized bone grafting from the distal radius have been encouraging, with numerous authors reporting the successful treatment of scaphoid nonunions.

Fabrication of a Neotrachea Using Engineered Cartilage

PubMed Central

Weidenbecher, Mark; Tucker, Harvey M.; Awadallah, Amad; Dennis, James E.

2008-01-01

Objectives Surgical management of long-segment tracheal stenosis is an ongoing problem. Many types of tracheal prostheses have been tried but with limited success because of immune rejection, graft ischemia, or restenosis. Tissue engineered cartilage may offer a solution to this problem, although scaffolds, which are currently often used for support, can lead to biocompatibility problems. This study investigated the feasibility of scaffold-free cartilage to tissue engineer a vascularized neotrachea in rabbits. Study Design Animal study. Methods Autologous neotracheal constructs were implanted in the abdomen of six New Zealand white rabbits. Auricular chondrocytes were used to engineer scaffold-free cartilage sheets. A muscle flap raised from the external abdominal oblique muscle and the engineered cartilage were wrapped around a silicone stent to fabricate a vascularized neotrachea in vivo. In two of the six rabbits, a full thickness skin graft was used to create an epithelial lining. The constructs were harvested after either 6 or 10 weeks. Results All neotracheal constructs were healthy with well-vascularized and integrated layers. The implanted engineered cartilage underwent a remodeling process, forming a solid tracheal framework. Constructs harvested after 10 weeks proved to have significantly better mechanical properties than after 6 weeks and were comparable with the rabbit's native trachea. Conclusion Scaffold-free engineered cartilage can successfully fabricate a well-vascularized, autologous neotrachea with excellent mechanical properties. The results suggest that this approach can be used to reconstruct tracheal defects in rabbits. PMID:18197138

Clinicopathological correlation of psychosis and brain vascular changes in Alzheimer’s disease

PubMed Central

Ting, Simon Kang Seng; Hao, Ying; Chia, Pei Shi; Tan, Eng-King; Hameed, Shahul

2016-01-01

Psychosis is common in Alzheimer’s disease (AD). However, studies on neuropathology in vascular etiology contributing to psychosis in AD is lacking to date. The aim of this study was to investigate neuropathological vascular related changes in Alzheimer’s disease with psychosis. Data of patients with AD from the National Alzheimer’s Coordinating Center between 2005 to September 2013 was accessed and reviewed. Presence of psychosis was determined based on Neuropsychiatric Inventory Questionnaire taken from the last visit within one year prior to death, and patients were divided into psychosis positive and negative group. Comparison of clinical details and neuropathological vascular changes between the groups was performed using Wilcoxon rank sum test and Chi-square/ Fisher’s exact test. Significant variables were further included in a multivariate logistic model. Overall, 145 patients was included. Of these, 50 patients were psychosis positive. Presence of one or more cortical microinfarcts and moderate to severe arteriosclerosis was found to be positively associated with psychosis. Our results suggest vascular changes correlate with psychosis in Alzheimer’s disease. PMID:26868671

Whole-mount Confocal Microscopy for Adult Ear Skin: A Model System to Study Neuro-vascular Branching Morphogenesis and Immune Cell Distribution.

PubMed

Yamazaki, Tomoko; Li, Wenling; Mukouyama, Yoh-Suke

2018-03-29

Here, we present a protocol of a whole-mount adult ear skin imaging technique to study comprehensive three-dimensional neuro-vascular branching morphogenesis and patterning, as well as immune cell distribution at a cellular level. The analysis of peripheral nerve and blood vessel anatomical structures in adult tissues provides some insights into the understanding of functional neuro-vascular wiring and neuro-vascular degeneration in pathological conditions such as wound healing. As a highly informative model system, we have focused our studies on adult ear skin, which is readily accessible for dissection. Our simple and reproducible protocol provides an accurate depiction of the cellular components in the entire skin, such as peripheral nerves (sensory axons, sympathetic axons, and Schwann cells), blood vessels (endothelial cells and vascular smooth muscle cells), and inflammatory cells. We believe this protocol will pave the way to investigate morphological abnormalities in peripheral nerves and blood vessels as well as the inflammation in the adult ear skin under different pathological conditions.

Vascular Access Practice Patterns in Canada: A National Survey

PubMed Central

Dumaine, Chance; Kiaii, Mercedeh; Miller, Lisa; Moist, Louise; Oliver, Matthew J.; Lok, Charmaine E.; Hiremath, Swapnil; MacRae, Jennifer M.

2018-01-01

Background: One of the mandates of the Canadian Society of Nephrology’s (CSN) Vascular Access Working Group (VAWG) is to inform the nephrology community of the current status of vascular access (VA) practice within Canada. To better understand VA practice patterns across Canada, the CSN VAWG conducted a national survey. Objectives: (1) To inform on VA practice patterns, including fistula creation and maintenance, within Canada. (2) To determine the degree of consensus among Canadian clinicians regarding patient suitability for fistula creation and to assess barriers to and facilitators of fistula creation in Canada. Design: Development and implementation of a survey. Setting: Community and academic VA programs. Participants: Nephrologists, surgeons, and nurses who are involved in VA programs across Canada. Measurements: Practice patterns regarding access creation and maintenance, including indications and contraindications to fistula creation, as well as program-wide facilitators of and barriers to VA. Methods: A small group of CSN VAWG members determined the scope and created several VA questions which were then reviewed by 5 additional VAWG members (4 nephrologists and 1 VA nurse) to ensure that questions were clear and relevant. The survey was then tested by the remaining members of the VAWG and refinements were made. The final survey version was submitted electronically to relevant clinicians (nephrologists, surgeons, and nurses) involved or interested in VA across Canada. Questions centered around 4 major themes: (1) Practice patterns regarding access creation (preoperative assessment and maturation assessment), (2) Practice patterns regarding access maintenance (surveillance and salvage), (3) Indications and contraindications for arteriovenous (AV) access creation, and (4) Facilitators of and barriers to fistula creation and utilization. Results: Eighty-two percent (84 of 102) of invited participants completed the survey; the majority were nurses or VA coordinators (55%) with the remainder consisting of nephrologists (21%) and surgeons (20%). Variation in practice was noted in utility of preoperative Doppler ultrasound, interventions to assist nonmaturing fistulas, and procedures to salvage failing or thrombosed AV-access. Little consensus was seen regarding potential contraindications to AV-access creation (with the exception of limited life expectancy and poor vasculature on preoperative imaging, which had high agreement). Frequent barriers to fistula utilization were primary failure (77% of respondents) and long maturation times (73%). Respondents from centers with low fistula prevalence also cited long surgical wait times as an important barrier to fistula creation, whereas those from centers with high fistula prevalence cited access to multidisciplinary teams and interventional radiology as keys to successful fistula creation and utilization. Conclusions: There is significant variation in VA practice across Canada and little consensus among Canadian clinicians regarding contraindications to fistula creation. Further high-quality studies are needed with regard to appropriate fistula placement to help guide clinical practice. PMID:29511569

Characterization of two homeodomain transcription factors with critical but distinct roles in virulence in the vascular pathogen Verticillium dahliae

USDA-ARS?s Scientific Manuscript database

Vascular wilt caused by Verticillium dahliae is a destructive disease that represents a chronic economic problem for crop production worldwide. In this work, we characterized two new regulators of pathogenicity in this species. Vph1 (VDAG_06555) was identified in a candidate gene approach as a putat...

Efficacy of the EZ-IO needle driver for out-of-hospital intraosseous access--a preliminary, observational, multicenter study.

PubMed

Schalk, Richard; Schweigkofler, Uwe; Lotz, Gösta; Zacharowski, Kai; Latasch, Leo; Byhahn, Christian

2011-10-26

Intraosseous (IO) access represents a reliable alternative to intravenous vascular access and is explicitly recommended in the current guidelines of the European Resuscitation Council when intravenous access is difficult or impossible. We therefore aimed to study the efficacy of the intraosseous needle driver EZ-IO in the prehospital setting. During a 24-month period, all cases of prehospital IO access using the EZ-IO needle driver within three operational areas of emergency medical services were prospectively recorded by a standardized questionnaire that needed to be filled out by the rescuer immediately after the mission and sent to the primary investigator. We determined the rate of successful insertion of the IO needle, the time required, immediate procedure-related complications, the level of previous experience with IO access, and operator's subjective satisfaction with the device. 77 IO needle insertions were performed in 69 adults and five infants and children by emergency physicians (n = 72 applications) and paramedics (n = 5 applications). Needle placement was successful at the first attempt in all but 2 adults (one patient with unrecognized total knee arthroplasty, one case of needle obstruction after placement). The majority of users (92%) were relative novices with less than five previous IO needle placements. Of 22 responsive patients, 18 reported pain upon fluid administration via the needle. The rescuers' subjective rating regarding handling of the device and ease of needle insertion, as described by means of an analogue scale (0 = entirely unsatisfied, 10 = most satisfied), provided a median score of 10 (range 1-10). The EZ-IO needle driver was an efficient alternative to establish immediate out-of-hospital vascular access. However, significant pain upon intramedullary infusion was observed in the majority of responsive patients.

Use and outcome of radial versus femoral approach for primary PCI in patients with acute ST elevation myocardial infarction without cardiogenic shock: results from the ALKK PCI registry.

PubMed

Bauer, Timm; Hochadel, Matthias; Brachmann, Johannes; Schächinger, Volker; Boekstegers, Peter; Zrenner, Bernhard; Zahn, Ralf; Zeymer, Uwe

2015-10-01

This study sought to compare the use and outcome of radial versus femoral access in patients treated with primary percutaneous coronary intervention (PCI) for acute ST elevation myocardial infarction (STEMI) in clinical practice. The radial approach for PCI in patients with STEMI has been suggested to have a lower rate of complications and bleeding and to improve prognosis compared with the femoral approach. However, there still is a large regional and national variation in its use. Between 2008 and 2012 a total of 17,865 patients with STEMI without cardiogenic shock undergoing primary PCI were prospectively enrolled in the observational German PCI registry of the Arbeitsgemeinschaft leitende kardiologische Krankenhausärzte (ALKK). Transfemoral (TF) access was used in 15,270 (85.5%), transradial (TR) access in 2,530 (14.2%), and other access in 65 (0.3%) patients. In this analysis, 10,264 patients from 20 centers that had performed at least 5 TR-PCI for STEMI were included. This study compared TR-PCI (n = 2,454 23.9%) with TF-PCI (n = 7,810, 76.1%). Procedural success was high in both cohorts. Hospital mortality (1.8 vs. 5.1%, P < 0.001) and vascular access complications (0.3 vs. 1.8%, P < 0.001%) were lower in the TR group. In the multivariate analysis radial access was associated with an improved in-hospital survival rate (OR 0.47, 95% CI 0.35-0.65). The radial approach for PCI can be performed with excellent procedural success in selected STEMI patients and is associated with a lower rate of vascular access complications and hospital mortality. © 2015 Wiley Periodicals, Inc.

Rating scale for the assessment of competence in ultrasound-guided peripheral vascular access - a Delphi Consensus Study.

PubMed

Primdahl, Stine C; Todsen, Tobias; Clemmesen, Louise; Knudsen, Lars; Weile, Jesper

2016-09-21

Peripheral vascular access is vital for treatment and diagnostics of hospitalized patients. Ultrasound-guided vascular access (UGVA) is superior to the landmark technique. To ensure competence-based education, an assessment tool of UGVA competence is needed. We aimed to develop a global rating scale (RS) for assessment of UGVA competence based on opinions on the content from ultrasound experts in a modified Delphi consensus study. We included experts from anesthesiology, emergency medicine and radiology across university hospitals in Denmark. Nine elements were drafted based on existing literature and recommendations from international societies. In a multi-round survey, the experts rated the elements on a five-point Likert scale according to importance, and suggested missing elements. The final Delphi round occurred when >80% of the experts rated all elements ≥4 on the Likert scale. Sixteen experts consented to participate in the study, one withdrew consent prior to the first Delphi round, and 14 completed all three Delphi rounds. In the first Delphi round the experts excluded one element from the scale and changed the content of two elements. In the second Delphi round, the experts excluded one element from the scale. In the third Delphi round, consensus was obtained on the eight elements: preparation of utensils, ergonomics, preparation of the ultrasound device, identification of blood vessels, anatomy, hygiene, coordination of the needle, and completion of the procedure. We developed an RS for assessment of UGVA competence based on opinions of ultrasound experts through a modified Delphi consensus study.

Angiogenesis in tissue engineering: from concept to the vascularization of scaffold construct

NASA Astrophysics Data System (ADS)

Amirah Ishak, Siti; Pangestu Djuansjah, J. R.; Kadir, M. R. Abdul; Sukmana, Irza

2014-06-01

Angiogenesis, the formation of micro-vascular network from the preexisting vascular vessels, has been studied in the connection to the normal developmental process as well as numerous diseases. In tissue engineering research, angiogenesis is also essential to promote micro-vascular network inside engineered tissue constructs, mimicking a functional blood vessel in vivo. Micro-vascular network can be used to maintain adequate tissue oxygenation, nutrient transfer and waste removal. One of the problems faced by angiogenesis researchers is to find suitable in vitro assays and methods for assessing the effect of regulators on angiogenesis and micro-vessel formation. The assay would be reliable and repeatable with easily quantifiable with physiologically relevant. This review aims to highlights recent advanced and future challenges in developing and using an in vitro angiogenesis assay for the application on biomedical and tissue engineering research.

The impact of financial barriers on access to care, quality of care and vascular morbidity among patients with diabetes and coronary heart disease.

PubMed

Parikh, Puja B; Yang, Jie; Leigh, Steven; Dorjee, Kunchok; Parikh, Roopali; Sakellarios, Nicholas; Meng, Hongdao; Brown, David L

2014-01-01

The prevalence and consequences of financial barriers to health care among patients with multiple chronic diseases are poorly understood. We sought to assess the prevalence of self-reported financial barriers to health care among individuals with diabetes and coronary heart disease (CHD) and to determine their association with access to care, quality of care and clinical outcomes. The 2007 Centers for Disease Control Behavioral Risk Factor Surveillance Survey. Diabetic patients with CHD. Financial barriers to health care were defined by a self-reported time in the past 12 months when the respondent needed to see a doctor but could not because of cost. The primary clinical outcome was vascular morbidity—a composite of stroke, retinopathy, nonhealing foot sores or bilateral foot amputations. Among the 11,274 diabetics with CHD, 1,541 (13.7 %) reported financial barriers to health care. Compared to individuals without financial barriers, those with financial barriers had significantly reduced rates of medical assessments within the past 2 years, hemoglobin (Hgb) A1C measurements in the past year, cholesterol measurements at any time, eye and foot examinations within the past year, diabetic education, antihypertensive treatment, aspirin use and a higher prevalence of vascular morbidity. In multivariable analyses, financial barriers to health care were independently associated with reduced odds of medical checkups (Odds Ratio [OR], 0.61; 95 % Confidence Intervals [CI], 0.55–0.67), Hgb A1C measurement (OR, 0.85; 95 % CI, 0.77–0.94), cholesterol measurement (OR, 0.76; 95 % CI, 0.67–0.86), eye (OR, 0.85; 95 % CI, 0.79–0.92) and foot (OR, 0.92; 95 % CI, 0.84–1.00) examinations, diabetic education (OR, 0.93; 95 % CI, 0.87–0.99), aspirin use (OR, 0.88; 95 % CI, 0.81–0.96) and increased odds of vascular morbidity (OR, 1.23; 95 % CI, 1.14–1.33). In diabetic adults with CHD, financial barriers to health care were associated with impaired access to medical care, inferior quality of care and greater vascular morbidity. Eliminating financial barriers and adherence to guideline-based recommendations may improve the health of individuals with multiple chronic diseases.

Surgical management of vascular access related aneurysms to salvage dialysis access: case report and a systematic review of the literature.

PubMed

Furukawa, Hiroshi

2015-01-01

We retrospectively evaluated the surgical outcome of revising vascular access related aneurysms (VARAs) to salvage dialysis access. Twenty-six consecutive hemodialysis patients (mean age 67.6 years, range: 32-89 years) who presented with true or false VARA and underwent surgery between January 2006 and February 2011 were enrolled in this study, and comprised 11 women and 15 men. Aneurysms were true in 21 patients and false in five; native arteriovenous fistulas (AVFs) were reported in 23, including one infected native pseudoaneurysm, and arteriovenous prosthetic grafts (AVGs) in three. The mean aneurysm diameter was 29.8 ± 8.0 mm, ranging from 18 to 50 mm. Indications of surgical intervention were local pain, rapid enlargement of the aneurysm, and AVF failure due to stenosis. Surgical revision was performed by resection of VARA and concomitant creation of a new proximal arteriovenous anastomosis in 18 patients. Two aneurysms were ruptured by blunt dissection; however, bleeding did not occur due to prior clamping of the inflow artery without hemodynamic compromise. VARA plication was performed in one case in which severe calcified VARA could not be incised. No significant complications were reported, except for delayed wound healing in three patients and minor peripheral neuropathy in five. The postoperative course was uneventful without hospital mortality in all patients with VARA. Aggressive surgical management of VARAs is likely to become an acceptable procedure to salvage dialysis access and consistently maintain AVF or AVG function.

Avoiding and managing vascular injury during robotic-assisted radical prostatectomy

PubMed Central

Nunez Bragayrac, Luciano A.; Machuca, Victor; Garza Cortes, Roberto; Azhar, Raed A.

2015-01-01

There has been an increase in the number of urologic procedures performed robotically assisted; this is the case for radical prostatectomy. Currently, in the USA, 67% of prostatectomies are performed robotically assisted. With this increase in robotic urologic surgery it is clear that there are more surgeons in their learning curve, where most of the complications occur. Among the complications that can occur are vascular injuries. These can occur in the initial stages of surgery, such as in accessing the abdominal cavity, as well as in the intraoperative or postoperative setting. We present the most common vascular injuries in robot-assisted radical prostatectomy, as well as their management and prevention. We believe that it is of vital importance to be able to recognize these injuries so that they can be prevented. PMID:25642293

Pre and post-amputation mobility of trans-tibial amputees: correlation to medical problems, age and mortality.

PubMed

Johnson, V J; Kondziela, S; Gottschalk, F

1995-12-01

This retrospective study compares pre and post-amputation mobility and the influence of age and associated medical problems. Data from the charts of 120 male patients who underwent unilateral trans-tibial (below-knee) amputation at the Dallas Veteran's Administration Hospital between June, 1983 and October, 1991, were collected and analyzed. Mobility was assessed with a six level scale developed by Volpicelli et al. (1983). The presence of cardiac disease, pulmonary disease (COPD), peripheral vascular disease (PVD), diabetes mellitus, degenerative joint disease, blindness, cerebral vascular accident (CVA), and age are correlated with changes in mobility after amputation. Older patients had more medical problems and lower post-amputation scores Individual medical problems did not influence mobility scores, but the presence of COPD and PVD lowered pre-amputation mobility scores. Cardiac disease and diabetes mellitus influenced post-amputation mobility scores by lowering them, either together or individually. Regardless of age, however, patients with more medical problems were poor ambulators. The cause of amputation per se did not influence mobility scores.

Getting to the root of plant biology: impact of the Arabidopsis genome sequence on root research

PubMed Central

Benfey, Philip N.; Bennett, Malcolm; Schiefelbein, John

2010-01-01

Summary Prior to the availability of the genome sequence, the root of Arabidopsis had attracted a small but ardent group of researchers drawn to its accessibility and developmental simplicity. Roots are easily observed when grown on the surface of nutrient agar media, facilitating analysis of responses to stimuli such as gravity and touch. Developmental biologists were attracted to the simple radial organization of primary root tissues, which form a series of concentric cylinders around the central vascular tissue. Equally attractive was the mode of propagation, with stem cells at the tip giving rise to progeny that were confined to cell files. These properties of root development reduced the normal four-dimensional problem of development (three spatial dimensions and time) to a two-dimensional problem, with cell type on the radial axis and developmental time along the longitudinal axis. The availability of the complete Arabidopsis genome sequence has dramatically accelerated traditional genetic research on root biology, and has also enabled entirely new experimental strategies to be applied. Here we review examples of the ways in which availability of the Arabidopsis genome sequence has enhanced progress in understanding root biology. PMID:20409273

Iatrogenic popliteal artery injury in non arthroplasty knee surgery.

PubMed

Bernhoff, K; Björck, M

2015-02-01

We have investigated iatrogenic popliteal artery injuries (PAI) during non arthroplasty knee surgery regarding mechanism of injury, treatment and outcomes, and to identify successful strategies when injury occurs. In all, 21 iatrogenic popliteal artery injuries in 21 patients during knee surgery other than knee arthroplasty were identified from the Swedish Vascular Registry (Swedvasc) between 1987 and 2011. Prospective registry data were supplemented with case-records, including long-term follow-up. In total, 13 patients suffered PAI during elective surgery and eight during urgent surgery such as fracture fixation or tumour resection. Nine injuries were detected intra-operatively, five within 12 to 48 hours and seven > 48 hours post-operatively (two days to 23 years). There were 19 open vascular and two endovascular surgical repairs. Two patients died within six months of surgery. One patient required amputation. Only six patients had a complete recovery of whom had the vascular injury detected at time of injury and repaired by a vascular surgeon. Patients sustaining vascular injury during elective procedures are more likely to litigate (p = 0.029). We conclude that outcomes are poorer when there is a delay of diagnosis and treatment, and that orthopaedic surgeons should develop strategies to detect PAI early and ensure rapid access to vascular surgical support. ©2015 The British Editorial Society of Bone & Joint Surgery.

Vascular Dysfunction in Mother and Offspring During Preeclampsia: Contributions from Latin-American Countries.

PubMed

Giachini, Fernanda Regina; Galaviz-Hernandez, Carlos; Damiano, Alicia E; Viana, Marta; Cadavid, Angela; Asturizaga, Patricia; Teran, Enrique; Clapes, Sonia; Alcala, Martin; Bueno, Julio; Calderón-Domínguez, María; Ramos, María P; Lima, Victor Vitorino; Sosa-Macias, Martha; Martinez, Nora; Roberts, James M; Escudero, Carlos

2017-10-06

Pregnancy is a physiologically stressful condition that generates a series of functional adaptations by the cardiovascular system. The impact of pregnancy on this system persists from conception beyond birth. Recent evidence suggests that vascular changes associated with pregnancy complications, such as preeclampsia, affect the function of the maternal and offspring vascular systems, after delivery and into adult life. Since the vascular system contributes to systemic homeostasis, defective development or function of blood vessels predisposes both mother and infant to future risk for chronic disease. These alterations in later life range from fertility problems to alterations in the central nervous system or immune system, among others. It is important to note that rates of morbi-mortality due to pregnancy complications including preeclampsia, as well as cardiovascular diseases, have a higher incidence in Latin-American countries than in more developed countries. Nonetheless, there is a lack both in the amount and impact of research conducted in Latin America. An impact, although smaller, can be seen when research in vascular disorders related to problems during pregnancy is analyzed. Therefore, in this review, information about preeclampsia and endothelial dysfunction generated from research groups based in Latin-American countries will be highlighted. We relate the need, as present in many other countries in the world, for increased effective regional and international collaboration to generate new data specific to our region on this topic.

Matrix ageing and vascular impacts: focus on elastin fragmentation.

PubMed

Duca, Laurent; Blaise, Sébastien; Romier, Béatrice; Laffargue, Muriel; Gayral, Stéphanie; El Btaouri, Hassan; Kawecki, Charlotte; Guillot, Alexandre; Martiny, Laurent; Debelle, Laurent; Maurice, Pascal

2016-06-01

Cardiovascular diseases (CVDs) are the leading cause of death worldwide and represent a major problem of public health. Over the years, life expectancy has considerably increased throughout the world, and the prevalence of CVD is inevitably rising with the growing ageing of the population. The normal process of ageing is associated with progressive deterioration in structure and function of the vasculature, commonly called vascular ageing. At the vascular level, extracellular matrix (ECM) ageing leads to molecular alterations in long half-life proteins, such as elastin and collagen, and have critical effects on vascular diseases. This review highlights ECM alterations occurring during vascular ageing with a specific focus on elastin fragmentation and also the contribution of elastin-derived peptides (EDP) in age-related vascular complications. Moreover, current and new pharmacological strategies aiming at minimizing elastin degradation, EDP generation, and associated biological effects are discussed. These strategies may be of major relevance for preventing and/or delaying vascular ageing and its complications. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Vascular Cambium Development

PubMed Central

Nieminen, Kaisa; Blomster, Tiina; Helariutta, Ykä; Mähönen, Ari Pekka

2015-01-01

Secondary phloem and xylem tissues are produced through the activity of vascular cambium, the cylindrical secondary meristem which arises among the primary plant tissues. Most dicotyledonous species undergo secondary development, among them Arabidopsis. Despite its small size and herbaceous nature, Arabidopsis displays prominent secondary growth in several organs, including the root, hypocotyl and shoot. Together with the vast genetic resources and molecular research methods available for it, this has made Arabidopsis a versatile and accessible model organism for studying cambial development and wood formation. In this review, we discuss and compare the development and function of the vascular cambium in the Arabidopsis root, hypocotyl, and shoot. We describe the current understanding of the molecular regulation of vascular cambium and compare it to the function of primary meristems. We conclude with a look at the future prospects of cambium research, including opportunities provided by phenotyping and modelling approaches, complemented by studies of natural variation and comparative genetic studies in perennial and woody plant species. PMID:26078728

Vascular Damage and Kidney Transplant Outcomes: An Unfriendly and Harmful Link.

PubMed

Hernández, Domingo; Triñanes, Javier; Armas, Ana María; Ruiz-Esteban, Pedro; Alonso-Titos, Juana; Duarte, Ana; González-Molina, Miguel; Palma, Eulalia; Salido, Eduardo; Torres, Armando

2017-07-01

Kidney transplant (KT) is the treatment of choice for most patients with chronic kidney disease, but this has a high cardiovascular mortality due to traditional and nontraditional risk factors, including vascular calcification. Inflammation could precede the appearance of artery wall lesions, leading to arteriosclerosis and clinical and subclinical atherosclerosis in these patients. Additionally, mineral metabolism disorders and activation of the renin-angiotensin system could contribute to this vascular damage. Thus, understanding the vascular lesions that occur in KT recipients and the pathogenic mechanisms involved in their development could be crucial to optimize the therapeutic management and outcomes in survival of this population. This review focuses on the following issues: (1) epidemiological data framing the problem; (2) atheromatosis in KT patients: subclinical and clinical atheromatosis, involving ischemic heart disease, congestive heart failure, stroke and peripheral vascular disease; (3) arteriosclerosis and vascular calcifications; and (4) potential pathogenic mechanisms and their therapeutic targets. Copyright © 2017 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

A novel narrow profile articulating powered vascular stapler provides superior access and haemostasis equivalent to conventional devices†.

PubMed

Ng, Calvin S H; Pickens, Allan; Siegel, Julianne M; Clymer, Jeffrey W; Cummings, John F

2016-01-01

Current endoscopic transection devices are not optimized to meet the unique challenges posed by the task of vessel transection in difficult-to-access locations within the pleural cavity. The ECHELON FLEX™ powered vascular stapler (PVS) has been designed with four rows of staples instead of six, to decrease its size and enable more precise placement on fragile pulmonary vessels, using a narrower anvil than other commercially available transecting devices. This study was performed to determine whether the reduced number of staple rows affects haemostasis, and to assess surgeons' initial impression of the smaller stapler during in vivo usage. The new four-row stapler was compared with commercially available six-row articulating staplers via expert graders using a validated scale of haemostasis in vivo after application on porcine gastroepiploic pedicles and other thin- and thick-walled vessels. The new stapler was then compared with current products by practising thoracic surgeons (n = 27) during in vivo usage of simulated pulmonary procedures in a porcine model. The surgeons were also surveyed on the key attributes of the four-row stapler in relation to the six-row predicates. Haemostasis evaluated on an ordered scale was clinically equivalent between the test and predicate staplers, and was deemed acceptable for all thin- and thick-vascular tissue applications. Surgeons found no difference in haemostasis between the four- and six-row staplers (P = 0.486), and judged the four-row stapler superior in terms of access, reduced need for dissection, reduced stress of surgeon and precise control (P < 0.001 for all). The new ECHELON FLEX™ PVS provides haemostasis equivalent to six-row staplers. With a smaller anvil, narrower shaft and wider angle of articulation, the PVS demonstrated improved access capability for pulmonary vessel procedures. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery.

Hydrogen peroxide prevents vascular calcification induced ROS production by regulating Nrf-2 pathway.

PubMed

Zhang, Wensong; Li, Yi; Ding, Hanlu; Du, Yaqin; Wang, Li

2016-08-01

Although vascular calcification in end-stage renal disease (ESRD) represents a ubiquitous human health problem, effective therapies with limited side effects are still lacking, and the precise mechanisms are not fully understood. The Nrf-2/ARE pathway is a pivotal to regulate anti-oxidative responses in vascular calcification upon ESRD. Although Nrf-2 plays a crucial role in atherosclerosis, pulmonary fibrosis, and brain ischemia, the effect of Nrf-2 and oxidative stress on vascular calcification in ESRD patients is still unclear. The aim of this research was to study the protective role of hydrogen peroxide in vascular calcification and the mechanism of Nrf-2 and oxidative stress on vascular calcification. Here we used the rat vascular smooth muscle cell model of β-glycerophosphate-induced calcification resembling vascular calcification in ESRD to investigate the therapeutic effect of 0.01 mM hydrogen peroxide on vascular calcification and further explores the possible underlying mechanisms. Our current report shows the in vitro role of 0.01 mM hydrogen peroxide in protecting against intracellular ROS accumulation upon vascular calcification. Both hydrogen peroxide and sulforaphane pretreatment reduced ROS production, increased the expression of Nrf-2, and decreased the expression of Runx2 following calcification. Our study demonstrates that 0.01 mM hydrogen peroxide can effectively protect rat aortic vascular smooth muscle cells against oxidative stress by preventing vascular calcification induced ROS production through Nrf-2 pathway. These data might define an antioxidant role of hydrogen peroxide in vascular calcification upon ESRD.

Stem cell mobilization and collection from pediatric patients and healthy children.

PubMed

Karakukcu, Musa; Unal, Ekrem

2015-08-01

Today, hematopoietic stem cell transplantation (HSCT) is a standard treatment for a variety of conditions in children, including certain malignancies, hemoglobinopathies, bone marrow failure syndromes, immunodeficiency and inborn metabolic disease. Two fundamentally different types of HSCT are categorized by the source of the stem cells. The first, autologous HSCT represents infusion of patient's own hematopoietic stem cells (HSCs) obtained from the patient; the second, allogeneic HSCT refers to the infusion of HSCs obtained from a donor via bone marrow harvest or apheresis. Bone marrow has been the typical source for HSCs for pediatric donors. Bone marrow harvest is a safe procedure mainly related to mild and transient side effects. Recently, a dramatically increased use of mobilized peripheral blood stem cells (PBSCs) in the autologous as well as allogeneic setting has been seen worldwide. There are limited data comparing mobilization regimens; also mobilization practices vary widely in children. The most commonly used approach includes granulocyte colony stimulating factor (G-CSF) at 10 mg/kg/day as a single daily dose for 4 days before the day of leukapheresis. G-CSF induced pain was less reported in children compared to adult donors. For the collection, there are several technical problems, derived from the size of the patient or donor, which must be considered before and during the apheresis. Vascular access, extracorporeal circuit volume, blood flow rates are the main limiting factors for PBSC collection in small children. Most children younger than 12 years require central vascular access for apheresis; line placement may require either general anesthesia or conscious sedation and many of the complications arise from the central venous catheter. In this review, we discuss that the ethical considerations and some principals regarding children serving as stem cell donors and the commonest sources of HSCs are presented in children, together with a discussion of how to collect and process these cells. Copyright © 2015 Elsevier Ltd. All rights reserved.

Association of vascular access flow with short-term and long-term mortality in chronic haemodialysis patients: a retrospective cohort study.

PubMed

Wu, Chung-Kuan; Wu, Chia-Lin; Lin, Chia-Hsun; Leu, Jyh-Gang; Kor, Chew-Teng; Tarng, Der-Cherng

2017-09-24

To investigate the impact of vascular access flow (Qa) on vascular and all-cause mortality in chronic haemodialysis (HD) patients. Observational cohort study. Single centre. Adult chronic HD patients at the HD unit of Shin Kong Wu Ho-Su Memorial Hospital between 1 January 2003 and 31 December 2003 were recruited. Patients were excluded if they had arteriovenous fistula or arteriovenous graft failure within 3 months before the date of Qa measurement, were aged <18 years and had Qa levels of ≥2000mL/min. A total of 378 adult chronic HD patients were eventually enrolled for the study. The selected patients were evaluated with Qa and cardiac index (CI). They were divided into four groups according to three Qa cut-off points (500, 1000 and 1500 mL/min). Short-term and long-term vascular (cardiovascular or cerebrovascular) and all-cause mortality. Qa was positively correlated with CI ( r =0.48, p<0.001). A Qa level of <1000 mL/min was independently associated with 1-year all-cause mortality (adjusted OR, 6.04; 95% CI 1.64 to 22.16; p=0.007). Kaplan-Meier analysis revealed that the cumulative incidence rates of all-cause and vascular mortality were significantly higher in the patients with a Qa level of <1000 mL/min (log-rank test; all p<0.01). Furthermore, a Qa level of <1000 mL/min was independently associated with long-term all-cause mortality (adjusted HR, 1.62; 95% CI 1.11 to 2.37; p=0.013); however, the risk of vascular mortality did not significantly increase after adjustment for confounders. Qa is moderately correlated with cardiac function, and a Qa level of <1000 mL/min is an independent risk factor for both short-term and long-term all-cause mortality in chronic HD patients. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Psychological problems, self-esteem and body dissatisfaction in a sample of adolescents with brain lesions: A comparison with a control group.

PubMed

Pastore, Valentina; Colombo, Katia; Maestroni, Deborah; Galbiati, Susanna; Villa, Federica; Recla, Monica; Locatelli, Federica; Strazzer, Sandra

2015-01-01

This study aims to describe psychological problems, self-esteem difficulties and body dissatisfaction in a sample of adolescents with acquired brain lesions and to compare them with an age- and gender-matched control group. In an experimental design, the psychological profile of 26 adolescents with brain lesions of traumatic or vascular aetiology, aged 12-18 years, was compared with that of 18 typically-developing subjects. Moreover, within the clinical group, patients with TBI were compared with patients with vascular lesions. The psychological and adaptive profile of the adolescents was assessed by a specific protocol, including CBCL, VABS, RSES, EDI-2 and BES. Adolescents with brain lesions showed more marked psychological problems than their healthy peers; they also presented with a greater impairment of adaptive skills and a lower self-esteem. No significant differences were found between patients with traumatic lesions and patients with vascular lesions. Adolescents with acquired brain lesions were at higher risk to develop psychological and behavioural difficulties. Furthermore, in the clinical sample, some variables such as the long hospitalization and isolation from family and peers were associated to a greater psychological burden than the aetiology of the brain damage.

Placement of Upper Extremity Arteriovenous Access in Patients with Central Venous Occlusions: A Novel Technique.

PubMed

Murga, Allen G; Chiriano, Jason T; Bianchi, Christian; Sheng, Neha; Patel, Sheela; Abou-Zamzam, Ahmed M; Teruya, Theodore H

2017-07-01

Central venous occlusion is a common occurrence in patients with end-stage renal disease. Placement of upper extremity arteriovenous access in patients with occlusion of the brachiocephalic veins is often not an option. Avoidance of lower extremity vascular access can decrease morbidity and infection. The central venous lesions were crossed centrally via femoral access. The wire was retrieved in the neck extravascularly. A Hemodialysis Reliable Outflow catheter was then placed in the right atrium and completed with an arterial anastomosis. We describe a novel technique for placing upper extremity arteriovenous access in patients with occlusion of the brachiocephalic veins. This technique was utilized in 3 patients. The technical success was 100%. The placement of upper extremity arteriovenous access in patients with central venous occlusions is technically feasible. Published by Elsevier Inc.

A Computational Framework to Optimize Subject-Specific Hemodialysis Blood Flow Rate to Prevent Intimal Hyperplasia

NASA Astrophysics Data System (ADS)

Mahmoudzadeh, Javid; Wlodarczyk, Marta; Cassel, Kevin

2017-11-01

Development of excessive intimal hyperplasia (IH) in the cephalic vein of renal failure patients who receive chronic hemodialysis treatment results in vascular access failure and multiple treatment complications. Specifically, cephalic arch stenosis (CAS) is known to exacerbate hypertensive blood pressure, thrombosis, and subsequent cardiovascular incidents that would necessitate costly interventional procedures with low success rates. It has been hypothesized that excessive blood flow rate post access maturation which strongly violates the venous homeostasis is the main hemodynamic factor that orchestrates the onset and development of CAS. In this article, a computational framework based on a strong coupling of computational fluid dynamics (CFD) and shape optimization is proposed that aims to identify the effective blood flow rate on a patient-specific basis that avoids the onset of CAS while providing the adequate blood flow rate required to facilitate hemodialysis. This effective flow rate can be achieved through implementation of Miller's surgical banding method after the maturation of the arteriovenous fistula and is rooted in the relaxation of wall stresses back to a homeostatic target value. The results are indicative that this optimized hemodialysis blood flow rate is, in fact, a subject-specific value that can be assessed post vascular access maturation and prior to the initiation of chronic hemodialysis treatment as a mitigative action against CAS-related access failure. This computational technology can be employed for individualized dialysis treatment.

A semi-automated vascular access system for preclinical models

NASA Astrophysics Data System (ADS)

Berry-Pusey, B. N.; Chang, Y. C.; Prince, S. W.; Chu, K.; David, J.; Taschereau, R.; Silverman, R. W.; Williams, D.; Ladno, W.; Stout, D.; Tsao, T. C.; Chatziioannou, A.

2013-08-01

Murine models are used extensively in biological and translational research. For many of these studies it is necessary to access the vasculature for the injection of biologically active agents. Among the possible methods for accessing the mouse vasculature, tail vein injections are a routine but critical step for many experimental protocols. To perform successful tail vein injections, a high skill set and experience is required, leaving most scientists ill-suited to perform this task. This can lead to a high variability between injections, which can impact experimental results. To allow more scientists to perform tail vein injections and to decrease the variability between injections, a vascular access system (VAS) that semi-automatically inserts a needle into the tail vein of a mouse was developed. The VAS uses near infrared light, image processing techniques, computer controlled motors, and a pressure feedback system to insert the needle and to validate its proper placement within the vein. The VAS was tested by injecting a commonly used radiolabeled probe (FDG) into the tail veins of five mice. These mice were then imaged using micro-positron emission tomography to measure the percentage of the injected probe remaining in the tail. These studies showed that, on average, the VAS leaves 3.4% of the injected probe in the tail. With these preliminary results, the VAS system demonstrates the potential for improving the accuracy of tail vein injections in mice.

MR imaging of iliofemoral peripheral vascular calcifications using proton density-weighted, in-phase three-dimensional stack-of-stars gradient echo.

PubMed

Ferreira Botelho, Marcos P; Koktzoglou, Ioannis; Collins, Jeremy D; Giri, Shivraman; Carr, James C; Gupta, NavYash; Edelman, Robert R

2017-06-01

The presence of vascular calcifications helps to determine percutaneous access for interventional vascular procedures and has prognostic value for future cardiovascular events. Unlike CT, standard MRI techniques are insensitive to vascular calcifications. In this prospective study, we tested a proton density-weighted, in-phase (PDIP) three-dimensional (3D) stack-of-stars gradient-echo pulse sequence with approximately 1 mm 3 isotropic spatial resolution at 1.5 Tesla (T) and 3T to detect iliofemoral peripheral vascular calcifications and correlated MR-determined lesion volumes with CT angiography (CTA). The study was approved by the Institutional Review Board. The prototype PDIP stack-of-stars pulse sequence was applied in 12 patients with iliofemoral peripheral vascular calcifications who had undergone CTA. Vascular calcifications were well visualized in all subjects, excluding segments near prostheses or stents. The location, size, and shape of the calcifications were similar to CTA. Quantitative analysis showed excellent correlation (r 2  = 0.84; P < 0.0001) between MR- and CT-based measures of calcification volume. In one subject in whom three pulse sequences were compared, PDIP stack-of-stars outperformed cartesian 3D gradient-echo and point-wise encoding time reduction with radial acquisition (PETRA). In this pilot study, a PDIP 3D stack-of-stars gradient-echo pulse sequence with high spatial resolution provided excellent image quality and accurately depicted the location and volume of iliofemoral vascular calcifications. Magn Reson Med 77:2146-2152, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

Predicting vascular complications in percutaneous coronary interventions.

PubMed

Piper, Winthrop D; Malenka, David J; Ryan, Thomas J; Shubrooks, Samuel J; O'Connor, Gerald T; Robb, John F; Farrell, Karen L; Corliss, Mary S; Hearne, Michael J; Kellett, Mirle A; Watkins, Matthew W; Bradley, William A; Hettleman, Bruce D; Silver, Theodore M; McGrath, Paul D; O'Mears, John R; Wennberg, David E

2003-06-01

Using a large, current, regional registry of percutaneous coronary interventions (PCI), we identified risk factors for postprocedure vascular complications and developed a scoring system to estimate individual patient risk. A vascular complication (access-site injury requiring treatment or bleeding requiring transfusion) is a potentially avoidable outcome of PCI. Data were collected on 18,137 consecutive patients undergoing PCI in northern New England from January 1997 to December 1999. Multivariate regression was used to identify characteristics associated with vascular complications and to develop a scoring system to predict risk. The rate of vascular complication was 2.98% (541 cases). Variables associated with increased risk in the multivariate analysis included age >or=70, odds ratio (OR) 2.7, female sex (OR 2.4), body surface area <1.6 m(2) (OR 1.9), history of congestive heart failure (OR 1.4), chronic obstructive pulmonary disease (OR 1.5), renal failure (OR 1.9), lower extremity vascular disease (OR 1.4), bleeding disorder (OR 1.68), emergent priority (OR 2.3), myocardial infarction (OR 1.7), shock (1.86), >or=1 type B2 (OR 1.32) or type C (OR 1.7) lesions, 3-vessel PCI (OR 1.5), use of thienopyridines (OR 1.4) or use of glycoprotein IIb/IIIa receptor inhibitors (OR 1.9). The model performed well in tests for significance, discrimination, and calibration. The scoring system captured 75% of actual vascular complications in its highest quintiles of predicted risk. Predicting the risk of post-PCI vascular complications is feasible. This information may be useful for clinical decision-making and institutional efforts at quality improvement.

[Oral contraception, glucid metabolism and monitoring criteria].

PubMed

Gaspard, U

1988-02-01

Combined oral contraceptives (OCs) entail insulin resistence and decreased glucose tolerance proportional to their dose and type of progestin. Derivatives of 19-nortestosterone have more deleterious effects than do derivatives of 17-acetoxy progesterone. The effects are usually reversible and limited, and the diabetogenic role of currently available low-dose OCs is small. Metabolic and vascular risks must still be taken into account in prescribing OCs because hyperglycemia and hyperinsulinemia are significant vascular risk factors. Women with histories of OC use have increased risks of fatal and nonfatal myocardial infarct, cerebrovascular accidents, and peripheral vascular disease, but the increases are not always significant. Age and smoking are known to be primary risk factors whose effects are increased by OCs. Reduction of the estrogen dose of OCs may have resulted in a significant reduction of the venous thromboembolic risk, while reduction of the progestin dose may have resulted in a decreased incidence of venous accidents. The mechanisms of action by which OCs amplify existing vascular risks are largely unknown. Research with methods capable of quantifying insulin resistence suggests that a post-receptor intracellular effect is responsible for insulin resistence and diminished intracellular metabolism of glucose in users of OCs. Because OCs are ordinarily used by healthy young women over long periods of time with minimal medical supervision, it is desirable to identify cases in which cardiovascular and other undesirable secondary effects are likely. OCs are contraindicated for any woman with a history of cardiac accidents, venous or arterial vascular problems, or hypertension. Obesity is a relative contraindication because it may coexist with a problem of glucose metabolism and constitute a diabetic risk factor. Other diabetic risk factors that must be evaluated are age, family or personal history of gestational diabetics, and transitory problems of glucose tolerance. Low dose combined OCs have little effect on carbohydrate metabolism or glucose tolerance, but women with diabetic risk factors may be more sensitive to the vascular impact of OCs than other women. Weight, blood pressure, and fasting or nonfasting blood sugar should be assessed annually OC users. Obese women should undergo an endocrinologic and metabolic examination in the interests of general prevention before receiving a prescription for combined OCs. Women with family or personal histories of diabetic risk should be evaluated from a metabolic and vascular standpoint.

Cilostazol May Improve Maturation Rates and Durability of Vascular Access for Hemodialysis.

PubMed

Russell, Todd E; Kasper, Gregory C; Seiwert, Andrew J; Comerota, Anthony J; Lurie, Fedor

2017-04-01

Cilostazol is effective in controlling pathophysiological pathways similar or identical to those involved in nonmaturation and failure of the arteriovenous access. This case-control study examined whether cilostazol would improve maturation rates and durability of vascular access for hemodialysis. The treatment group included 33 patients who received cilostazol for ≥30 days prior to creation of a dialysis access and continued with cilostazol therapy for ≥60 days after surgery. The matched (gender, age, race, diabetes, and the year of surgery) control group included 116 patients who underwent the same procedure but did not receive cilostazol prior to and at least 3 months after surgery. Primary outcomes were maturation and, for those that matured, time of functioning access, defined as the time from the first use to irreparable failure of the access. Secondary outcomes were time to maturation, complications, and time to first complication. Study group patients were 3.8 times more likely to experience fistula maturation compared to the controls (88% vs 66%, RR = 3.8, 95% confidence interval: 1.3-11.6, P = .016). Fewer patients in the study group had complications (76% vs 92%, P = .025), and the time from construction of the fistula to the first complication was longer (345.6 ± 441 days vs 198.3 ± 185.0 days, P = .025). Time to maturation was similar in both groups (119.3 ± 62.9 days vs 100.2 ± 61.7 days, P = .2). However, once matured, time to failure was significantly longer in the treatment group (903.7 ± 543.6 vs 381.6 ± 317.2 days, P = .001). Multivariate analysis confirmed that the likelihood of maturation was significantly higher in the treatment group patients. These results suggest that dialysis access patients may benefit from preoperative and postoperative cilostazol therapy. If confirmed by a randomized trial, this treatment will have a major beneficial impact on patients dependent on a well-functioning access for their hemodialysis.

Percutaneous access versus surgical cut down for TAVR: Where do we go from here?

PubMed

Ates, Ismail; Cilingiroglu, Mehmet

2018-06-01

Transcatheter aortic valve replacement is now the standard of care for severe symptomatic aortic stenosis patients who are at high-surgical risk. Percutaneous approach without a surgical cut down has been increasingly adapted by some centers in USA. Percutaneous approach seems to be associated with shorter hospital stay, similar short and late vascular complications, less disabling stroke, similar mortality as well as significantly less hospital cost. However, this technique also requires operators to be able to manage any vascular complications using advanced endovascular interventions to achieve complete hemostasis. © 2018 Wiley Periodicals, Inc.

Biomimetic, ultrathin and elastic hydrogels regulate human neutrophil extravasation across endothelial-pericyte bilayers.

PubMed

Lauridsen, Holly M; Gonzalez, Anjelica L

2017-01-01

The vascular basement membrane-a thin, elastic layer of extracellular matrix separating and encasing vascular cells-provides biological and mechanical cues to endothelial cells, pericytes, and migrating leukocytes. In contrast, experimental scaffolds typically used to replicate basement membranes are stiff and bio-inert. Here, we present thin, porated polyethylene glycol hydrogels to replicate human vascular basement membranes. Like commercial transwells, our hydrogels are approximately 10μm thick, but like basement membranes, the hydrogels presented here are elastic (E: 50-80kPa) and contain a dense network of small pores. Moreover, the inclusion of bioactive domains introduces receptor-mediated biochemical signaling. We compare elastic hydrogels to common culture substrates (E: >2GPa) for human endothelial cell and pericyte monolayers and bilayers to replicate postcapillary venules in vitro. Our data demonstrate that substrate elasticity facilitates differences in vascular phenotype, supporting expression of vascular markers that are increasingly replicative of venules. Endothelial cells differentially express vascular markers, like EphB4, and leukocyte adhesion molecules, such as ICAM-1, with decreased mechanical stiffness. With porated PEG hydrogels we demonstrate the ability to evaluate and observe leukocyte recruitment across endothelial cell and pericyte monolayers and bilayers, reporting that basement membrane scaffolds can significantly alter the rate of vascular migration in experimental systems. Overall, this study demonstrates the creation and utility of a new and accessible method to recapture the mechanical and biological complexity of human basement membranes in vitro.

Minimally invasive optical biopsy for oximetry

NASA Astrophysics Data System (ADS)

van der Putten, Marieke A.; Brewer, James M.; Harvey, Andrew R.

2017-02-01

The study of localised oxygen saturation in blood vessels can shed light on the etiology and progression of many diseases with which hypoxia is associated. For example, hypoxia in the tendon has been linked to early stages of rheumatoid arthritis, an auto-immune inflammatory disease. Vascular oximetry of deep tissue presents significant challenges as vessels are not optically accessible. In this paper, we present a novel multispectral imaging technique for vascular oximetry, and recent developments made towards its adaptation for minimally invasive imaging. We present proof-of-concept of the system and illumination scheme as well as the analysis technique. We present results of a validation study performed in vivo on mice with acutely inflamed tendons. Adaptation of the technique for minimally invasive microendoscopy is also presented, along with preliminary results of minimally invasive ex vivo vascular oximetry.

[Surgical learning curve for creation of vascular accesses for haemodialysis: value of medico-radio-surgical collaboration].

PubMed

Van Glabeke, Emmanuel; Belenfant, Xavier; Barrou, Benoît; Adhemar, Jean-Pierre; Laedrich, Joëlle; Mavel, Marie-Christine; Challier, Emmanuel

2005-04-01

Creation of a vascular access (VA) for haemodialysis is a surgical procedure which comprises a failure rate related to the quality of the vessels and the operator's experience. The authors report the first 2 years of a young urologist's experience with this procedure in a local hospital in collaboration with the nephrology team. Patients undergoing creation of VA were divided into 2 chronological groups. The patient's age and gender, the cause of renal failure, the presence of diabetes, clinical examination of the upper limb, preoperative assessment of upper limb vessels, the type of anaesthesia, the operating time and the start of dialysis after the operation, as well as the functional results of the VA at 6 months were studied. Results concerning the patients of the first period were discussed by the operator and the nephrology team. During the first 9 months, 28 patients were operated, corresponding to 36 operations including 32 direct fistulas. Over the following 15 months, 61 patients were operated, with the creation of 63 VAs, including 55 direct fistulas. The failure rate (thrombosis or non-functioning VA) decreased from 32.1% to 11.1% (p=0.07), while the 2 groups were globally comparable. Evaluation of a new surgical procedure shows a number of failures, as for all learning curves. However, it helps to improve the results. Collaboration with nephrologists must comprise a discussion allowing the acceptance of certain failures, as they reflect compliance with a strategy of preservation of the vascular capital and a rational attempt to avoid a non-essential proximal access or bypass graft. The support of a motivated radiology team (preoperative assessment and management of complications) and the assistance of a more experienced operator are essential.

Differences in Stylet Sheath Occurrence and the Fibrous Ring (Sclerenchyma) between xCitroncirus Plants Relatively Resistant or Susceptible to Adults of the Asian Citrus Psyllid Diaphorina citri (Hemiptera: Liviidae)

PubMed Central

Ammar, El-Desouky; Richardson, Matthew L.; Abdo, Zaid; Hall, David G.; Shatters, Robert G.

2014-01-01

The Asian citrus psyllid (ACP, Diaphorina citri, Hemiptera: Liviidae), is the principal vector of the phloem-limited bacteria strongly associated with huanglongbing (HLB), the world’s most serious disease of citrus. Host plant resistance may provide an environmentally safe and sustainable method of controlling ACP and/or HLB. Two xCitroncirus accessions (hybrids of Poncirus trifoliata and Citrus spp.), that are relatively resistant (UN-3881) or relatively susceptible (Troyer-1459) to ACP adults with regard to adult longevity, were compared in relation to ACP feeding behavior and some structural features of the leaf midrib. The settling (putative feeding/probing) sites of ACP adults on various parts of the leaf were not influenced primarily by plant accession. However, fewer ACP stylet sheaths were found in the midrib and fewer stylet sheath termini reached the vascular bundle (phloem and/or xylem) in UN-3881 compared to Troyer-1459 plants. Furthermore, in midribs of UN-3881 leaves the fibrous ring (sclerenchyma) around the phloem was significantly wider (thicker) compared to that in midribs of Troyer-1459 leaves. Our data indicate that feeding and/or probing by ACP adults into the vascular bundle is less frequent in the more resistant (UN-3881) than in the more susceptible (Troyer-1459) accessions. Our results also suggest that the thickness of the fibrous ring may be a barrier to stylet penetration into the vascular bundle, which is important for successful ACP feeding on the phloem and for transmitting HLB-associated bacteria. These results may help in the development of citrus plants resistant to ACP, which in turn could halt or slow the spread of the HLB-associated bacteria by this vector. PMID:25343712

Adherence of healthcare professionals to evidence-based clinical practice guidelines in the management of hemodialysis patients, Khartoum State, Sudan.

PubMed

Abdelwahab, Hisham; Shigidi, Mazin; El-Tohami, Alyaa; Ibrahim, Lamees

2013-05-01

Hemodialysis (HD) is a complex procedure with many specifications and requires adherence to a set of particular clinical practice guidelines. These guidelines had already been established by globally acclaimed renal authorities and their implementation was shown to correlate with patients' morbidity and mortality. This study was conducted to evaluate the adherence of healthcare professionals to the evidence-based clinical practice patterns in Khartoum State HD units. A cross-sectional study was conducted in Khartoum State HD units during the period from September 2010 to January of 2011. Data was collected from the healthcare professionals using a specially designed checklist. The checklist included the evidence-based clinical practice guidelines for the HD vascular access, HD adequacy, anemia of chronic kidney disease (CKD), nutrition, cardiovascular risk assessment, and hepatitis B and C virus infection control. Implementation of these guidelines was evaluated, and further graded using a Likert-type scale. Four randomly selected HD units were included in the study. The rate of implementation of the HD vascular access guidelines was 54.8%, adequacy guidelines 57%, anemia of CKD 68.8%, nutrition 58.4%, cardiovascular risk assessment 57%, and hepatitis B and C infection control guidelines was 79.2%. Overall, the four HD units assessed showed moderate deviations from the practice guidelines of anemia of CKD and hepatitis B and C infection control. Extreme deviations from the clinical practice guidelines were seen in HD vascular access practices, adequacy assessments, nutrition and cardiovascular risk assessment. Hemodialysis services in Khartoum State are in need of great improvements regarding adherence to protocols and the standards of care.

Socioeconomic status and transient ischaemic attack/stroke: a prospective observational study.

PubMed

Kerr, Gillian D; Higgins, Peter; Walters, Matthew; Ghosh, Sandip K; Wright, Fiona; Langhorne, Peter; Stott, David J

2011-01-01

Lower socioeconomic status (SES) is associated with an increased risk of stroke but the mechanisms are unclear. We aimed to determine whether low-SES stroke/transient ischaemic attack (TIA) patients have a greater burden of vascular risk factors/co-morbidity and reduced health care access. We prospectively studied 467 consecutive stroke and TIA patients from 3 Scottish hospitals (outpatients and inpatients) during 2007/2008. We recorded vascular risk factors, stroke severity, co-morbidity measures, investigations and health service utilisation. SES was derived from postcodes using Scottish Neighbourhood Statistics and analysed in quartiles. TIA/stroke patients in the lowest SES quartile were younger (64 years, SD 14.1) than those in the highest quartile (72 years, SD 12.9; p < 0.0001). They were more likely to be current smokers (42 vs. 22%; p = 0.001) but there was no association with other vascular risk factors/co-morbidity. There was a trend for those with lower SES to have a more severe stroke [modified National Institutes of Health Stroke Scale score and interquartile range: 4 (2-6) vs. 3 (1-5); multivariate p = 0.05]. Lower SES groups were less likely to have neuro-imaging (82 vs. 90%; p = 0.036) or an electrocardiogram (72 vs. 87%; p = 0.003), but differences were no longer significant on multivariate analysis. However, there was equal access to stroke unit care. Low-SES TIA and stroke patients are younger and have a more severe deficit; an increased prevalence of smoking is likely to be a major contributor. We found equal access to stroke unit care for low-SES patients. Copyright © 2010 S. Karger AG, Basel.

Comparison of TR Band™ and VasoStat™ Hemostasis Devices following Transpedal Catheterization for Lower Extremity Revascularization for Peripheral Arterial Disease.

PubMed

Kwan, Tak W; Patel, Apurva; Parikh, Roosha; Auguste, Uschi; Rosero, Hugo; Huang, Yili; Liou, Michael; Ratcliffe, Justin; Puma, Joseph

2016-08-01

Transpedal access is increasingly utilized for peripheral vascular catheterization. There is a paucity of data on the use of radial hemostasis devices as an alternative to manual compression for achievement of hemostasis after this approach. To compare safety and efficacy of two hemostasis devices following transpedal catheterization for lower extremity revascularization for peripheral arterial disease. A consecutive cohort of patients with bilateral Rutherford 2-5 disease who underwent transpedal catheterization for peripheral vascular interventions were retrospectively analyzed. In each patient, retrograde tibial artery access was obtained, a 4 French sheath was placed, and all revascularization was performed via tibial access. In all patients, a TR Band™ (Terumo Medical, n = 215) and/or VasoStat™ (Forge Medical, n = 99) were used to apply puncture site compression, following removal of the tibial sheath until hemostasis was achieved. Safety and efficacy of each device was compared. Puncture site hemostasis was achieved in all patients within 2 hours of sheath removal facilitating early discharge. Two access site pseudoaneurysms occurred within 30 days of revascularization, one of which followed TR Band™ placement and the other following VasoStat™ placement (P = 0.53). Each patient was successfully treated with ultrasound-guided thrombin injection. Loss of access site patency by duplex ultrasound occurred in 2 patients following the TR Band™ and a single patient following the VasoStat™ (P = 1.0). Both the TR Band™ and the VasoStat™ were effective in achieving hemostasis following transpedal catheterization with low rates of complications. © 2016, Wiley Periodicals, Inc.

The Double Mandibular Osteotomy for Vascular and Tumor Surgery of the Parapharyngeal Space.

PubMed

Schlieve, Thomas; Carlson, Eric R; Freeman, Michael; Buckley, Ryan; Arnold, Josh

2017-05-01

The purposes of this study are to describe our experience using a double mandibular osteotomy for access to the parapharyngeal space in vascular and tumor surgery and to report on the outcomes and complications of this procedure. We designed and implemented a case series to review the medical records of all patients treated with a double mandibular osteotomy for parapharyngeal space access from 1994 to 2016. Patient demographic characteristics, indications for the procedure, outcomes, and complications were recorded. A total of 17 patients underwent a double mandibular osteotomy procedure for access to the parapharyngeal space during the study period. There were 7 men (41%) and 10 women (59%) comprising the cohort. The average age was 57 years (range, 29 to 75 years). The follow-up period ranged from 6 to 98 months (mean, 40 months), and 7 patients (41%) were tobacco users at the time of surgery. The most common indication was high internal carotid artery stenosis (n = 6) followed by carotid body paraganglioma (n = 3). Average blood loss was 186 mL, and there were no deaths during the study period. Eight postoperative complications were noted in 7 patients (41%). No procedures were aborted or compromised because of inadequate parapharyngeal space access. All patients showed clinical and radiographic signs of healing of the osteotomy sites. The double mandibular osteotomy provides adequate access to the parapharyngeal space for effective tumor removal and high carotid surgical intervention with acceptable patient morbidity and complications. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Survey of home hemodialysis patients and nursing staff regarding vascular access use and care.

PubMed

Spry, Leslie A; Burkart, John M; Holcroft, Christina; Mortier, Leigh; Glickman, Joel D

2015-04-01

Vascular access infections are of concern to hemodialysis patients and nurses. Best demonstrated practices (BDPs) have not been developed for home hemodialysis (HHD) access use, but there have been generally accepted practices (GAPs) endorsed by dialysis professionals. We developed a survey to gather information about training provided and actual practices of HHD patients using the NxStage System One HHD machine. We used GAP to assess training used by nurses to teach HHD access care and then assess actual practice (adherence) by HHD patients. We also assessed training and adherence where GAPs do not exist. We received a 43% response rate from patients and 76% response from nurses representing 19 randomly selected HHD training centers. We found that nurses were not uniformly instructing HHD patients according to GAP, patients were not performing access cannulation according to GAP, nor were they adherent to their training procedures. Identification of signs and symptoms of infection was commonly trained appropriately, but we observed a reluctance to report some signs and symptoms of infection by patients. Of particular concern, when aggregating all steps surveyed, not a single nurse or patient reported training or performing all steps in accordance with GAP. We also identified practices for which there are no GAPs that require further study and may or may not impact outcomes such as infection. Further research is needed to develop strategies to implement and expand GAP, measure outcomes, and ultimately develop BDP for HHD to improve infectious complications. © 2014 The Authors. Hemodialysis International published by Wiley Periodicals, Inc. on behalf of International Society for Hemodialysis.

Prefabrication of axial vascularized tissue engineering coral bone by an arteriovenous loop: a better model.

PubMed

Dong, Qing-shan; Shang, Hong-tao; Wu, Wei; Chen, Fu-lin; Zhang, Jun-rui; Guo, Jia-ping; Mao, Tian-qiu

2012-08-01

The most important problem for the survival of thick 3-dimensional tissues is the lack of vascularization in the context of bone tissue engineering. In this study, a modified arteriovenous loop (AVL) was developed to prefabricate an axial vascularized tissue engineering coral bone in rabbit, with comparison of the arteriovenous bundle (AVB) model. An arteriovenous fistula between rabbit femoral artery and vein was anastomosed to form an AVL. It was placed in a circular side groove of the coral block. The complex was wrapped with an expanded-polytetrafluoroethylene membrane and implanted beneath inguinal skin. After 2, 4, 6 and 8 weeks, the degree of vascularization was evaluated by India ink perfusion, histological examination, vascular casts, and scanning electron microscopy images of vascular endangium. Newly formed fibrous tissues and vasculature extended over the surfaces and invaded the interspaces of entire coral block. The new blood vessels robustly sprouted from the AVL. Those invaginated cavities in the vascular endangium from scanning electron microscopy indicated vessel's sprouted pores. Above indexes in AVL model are all superior to that in AVB model, indicating that the modified AVL model could more effectively develop vascularization in larger tissue engineering bone. Copyright © 2012 Elsevier B.V. All rights reserved.

Successful Retrieval of an Embolized Vascular Closure Device (Angio-Seal{sup ®}) After Peripheral Angioplasty

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jud, Philipp, E-mail: philipp.jud@medunigraz.at; Portugaller, Rupert; Bohlsen, Dennis

A 55-year-old male with peripheral arterial disease underwent angioplasty of the right lower limb arteries via antegrade femoral access. Angio-Seal{sup ®} closure device was used to treat the puncture site, whereby the intravascular sealing anchor accidentally embolized into the malleolar region of the right posterior tibial artery. Successful retrieval of the anchor was accomplished by a SpiderFX embolic protection device. This technique may be a useful approach to retrieve embolized foreign bodies via endovascular access.

42 CFR 494.110 - Condition: Quality assessment and performance improvement.

Code of Federal Regulations, 2013 CFR

2013-10-01

... improvement. 494.110 Section 494.110 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF... RENAL DISEASE FACILITIES Patient Care § 494.110 Condition: Quality assessment and performance... renal bone disease. (iv) Anemia management. (v) Vascular access. (vi) Medical injuries and medical...

42 CFR 494.110 - Condition: Quality assessment and performance improvement.

Code of Federal Regulations, 2014 CFR

2014-10-01

... improvement. 494.110 Section 494.110 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF... RENAL DISEASE FACILITIES Patient Care § 494.110 Condition: Quality assessment and performance... renal bone disease. (iv) Anemia management. (v) Vascular access. (vi) Medical injuries and medical...

42 CFR 494.110 - Condition: Quality assessment and performance improvement.

Code of Federal Regulations, 2012 CFR

2012-10-01

... improvement. 494.110 Section 494.110 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF... RENAL DISEASE FACILITIES Patient Care § 494.110 Condition: Quality assessment and performance... renal bone disease. (iv) Anemia management. (v) Vascular access. (vi) Medical injuries and medical...

Flushing ports of totally implantable venous access devices, and impact of the Huber point needle bevel orientation: experimental tests and numerical computation.

PubMed

Guiffant, Gérard; Durussel, Jean Jacques; Flaud, Patrice; Vigier, Jean Pierre; Merckx, Jacques

2012-01-01

The use of totally implantable venous access devices developed as a medical device allowing mid- and long-term, frequent, repeated, or continuous injection of therapeutic products, by vascular, cavitary, or perineural access. The effective flushing of these devices is a central element to assure long-lasting use. Our experimental work demonstrates that directing the Huber point needle opening in the diametrically opposite direction of the implantable port exit channel increases the flushing efficiency. These results are consolidated by numerical computations, which support recommendations not only for their maintenance, but also for their use.

Flushing ports of totally implantable venous access devices, and impact of the Huber point needle bevel orientation: experimental tests and numerical computation

PubMed Central

Guiffant, Gérard; Durussel, Jean Jacques; Flaud, Patrice; Vigier, Jean Pierre; Merckx, Jacques

2012-01-01

The use of totally implantable venous access devices developed as a medical device allowing mid- and long-term, frequent, repeated, or continuous injection of therapeutic products, by vascular, cavitary, or perineural access. The effective flushing of these devices is a central element to assure long-lasting use. Our experimental work demonstrates that directing the Huber point needle opening in the diametrically opposite direction of the implantable port exit channel increases the flushing efficiency. These results are consolidated by numerical computations, which support recommendations not only for their maintenance, but also for their use. PMID:23166455

Validation of an effective, low cost, Free/open access 3D-printed stethoscope

PubMed Central

Pavlosky, Alexander; Glauche, Jennifer; Chambers, Spencer; Al-Alawi, Mahmoud; Yanev, Kliment

2018-01-01

The modern acoustic stethoscope is a useful clinical tool used to detect subtle, pathological changes in cardiac, pulmonary and vascular sounds. Currently, brand-name stethoscopes are expensive despite limited innovations in design or fabrication in recent decades. Consequently, the high cost of high quality, brand name models serves as a barrier to clinicians practicing in various settings, especially in low- and middle-income countries. In this publication, we describe the design and validation of a low-cost open-access (Free/Libre) 3D-printed stethoscope which is comparable to the Littmann Cardiology III for use in low-access clinics. PMID:29538426

Ultrasound-Guided Vascular Access Simulator for Medical Training: Proposal of a Simple, Economic and Effective Model.

PubMed

Fürst, Rafael Vilhena de Carvalho; Polimanti, Afonso César; Galego, Sidnei José; Bicudo, Maria Claudia; Montagna, Erik; Corrêa, João Antônio

2017-03-01

To present a simple and affordable model able to properly simulate an ultrasound-guided venous access. The simulation was made using a latex balloon tube filled with water and dye solution implanted in a thawed chicken breast with bones. The presented model allows the simulation of all implant stages of a central catheter. The obtained echogenicity is similar to that observed in human tissue, and the ultrasound identification of the tissues, balloon, needle, wire guide and catheter is feasible and reproducible. The proposed model is simple, economical, easy to manufacture and capable of realistically and effectively simulating an ultrasound-guided venous access.

Application of different variants of the BEM in numerical modeling of bioheat transfer problems.

PubMed

Majchrzak, Ewa

2013-09-01

Heat transfer processes proceeding in the living organisms are described by the different mathematical models. In particular, the typical continuous model of bioheat transfer bases on the most popular Pennes equation, but the Cattaneo-Vernotte equation and the dual phase lag equation are also used. It should be pointed out that in parallel are also examined the vascular models, and then for the large blood vessels and tissue domain the energy equations are formulated separately. In the paper the different variants of the boundary element method as a tool of numerical solution of bioheat transfer problems are discussed. For the steady state problems and the vascular models the classical BEM algorithm and also the multiple reciprocity BEM are presented. For the transient problems connected with the heating of tissue, the various tissue models are considered for which the 1st scheme of the BEM, the BEM using discretization in time and the general BEM are applied. Examples of computations illustrate the possibilities of practical applications of boundary element method in the scope of bioheat transfer problems.

Transcatheter aortic valve replacement and vascular complications definitions.

PubMed

Van Mieghem, Nicolas M; Généreux, Philippe; van der Boon, Robert M A; Kodali, Susheel; Head, Stuart; Williams, Matthew; Daneault, Benoit; Kappetein, Arie-Pieter; de Jaegere, Peter P; Leon, Martin B; Serruys, Patrick W

2014-03-20

Transcatheter aortic valve replacement (TAVR) requires large calibre catheters and is therefore associated with increased vascular complications. The aim of this study was to illustrate the impact of the different definitions of major vascular complications on their incidence and to underscore the importance of uniform reporting. We pooled dedicated databases of consecutive patients undergoing TAVR from two tertiary care facilities and looked for the incidence of major vascular complications using various previously reported definitions. The level of agreement (Kappa statistic) between the respective definitions and the Valve Academic Research Consortium (VARC) consensus definition of vascular complications was assessed. A total of 345 consecutive patients underwent transfemoral TAVR and were included in this analysis. A completely percutaneous access and closure technique was applied in 96% of cases. Arterial sheath size ranged between 18 and 24 Fr, the majority being 18 Fr (60%). Procedural success was reached in 94.5%. Depending on the definition used, major vascular complications occurred in 5.2-15.9% of patients. According to the VARC definitions, the rate of major and minor vascular complications was 9.0% and 9.6%, respectively. Major vascular complications according to VARC criteria demonstrated at least a substantial level of agreement with the SOURCE registry (k 0.80), the UK registry (k 0.82) the Italian registry (k 0.72) and "FRANCE" registry (k 0.70) definitions, compared to a moderate level of agreement with the definitions used in the German registry ( 0.47) and the 18 Fr Safety and Efficacy study (k 0.42). Minor complications according to VARC demonstrated a moderate agreement only with vascular complications using the German registry definition (k 0.54). Non-uniformity in how vascular complications are defined precludes any reliable comparison between previously reported TAVR registries. The VARC consensus document offers standardised endpoint definitions and should be universally adopted to obtain better insights into global TAVR experience.

Vascular labeling of the head and neck vessels: Technique, advantages and limitations.

PubMed

Gálvez, Alba; Caraballo, José-Leonardo; Manzanares-Céspedes, María-Cristina; Valdivia-Gandur, Iván; Figueiredo, Rui; Valmaseda-Castellón, Eduard

2017-05-01

Vascular staining techniques have been used to describe the vascular structures of several anatomic areas. However, few reports have described this procedure in the head and neck region. This paper describes a head and neck vascular labeling procedure, and describes some of the technical complications that may occur. Fifteen specimen cadaver heads were prepared. After drying the vascular system, the internal carotid arteries were ligated and a solution with latex and a gelling agent was injected into the internal carotid arteries and external jugular veins. Two different colors were employed to differentiate arteries from veins. A total of 60ml latex was injected into each blood vessel. Subsequently, the specimens were refrigerated at 5°C for a minimum of 24 hours. Finally, a dissection was performed to identify the venous and arterial systems of the maxillofacial region. In most specimens, correct identification of the vascular structures (lingual artery, pterigoyd plexus, and the major palatal arteries, among others) was possible. However, in three heads a major technical problem occurred (the latex remained liquid), making the dissection unfeasible. Other minor complications such as latex obstruction due to the presence of atheromas were found in two further specimens. The vascular labeling technique is a predictable, effective and simple method for analyzing the vascular system of the maxillofacial area in cadaveric studies, including vessels of reduced diameter or with an intraosseous course. This procedure can be especially useful to teach vascular anatomy to dental students and postgraduate residents. Key words: Blood vessels, vascular casting, vascular labeling, head and neck arteries, carotid arteries, jugular veins.

The vascular and neurogenic factors associated with erectile dysfunction in patients after pelvic fractures.

PubMed

Guan, Yong; Wendong, Sun; Zhao, Shengtian; Liu, Tongyan; Liu, Yuqiang; Zhang, Xiulin; Yuan, Mingzhen

2015-01-01

Erectile dysfunction (ED) is a common complication of pelvic fractures. To identify the vascular and neurogenic factors associated with ED, 120 patients admitted with ED after traumatic pelvic fracture between January 2009 and June 2013 were enrolled in this study. All patients answered the International Index of Erectile Function (IIEF-5) questionnaire. Nocturnal penile tumescence (NPT) testing confirmed the occurrence of ED in 96 (80%) patients on whom penile duplex ultrasound and neurophysiological testing were further performed. Of these ED patients 29 (30%) were demonstrated only with vascular abnormality, 41 (42.7%) were detected only with neural abnormality, 26 (27.1%) revealed mixed abnormalities. Of the 55 patients (29+26) with vascular problems, 7 patients (12.7%) with abnormal arterial response to intracavernous injection of Bimix (15mg papaverine and 1mg phentolamine), 31 (56.4%) with corporal veno-occlusive dysfunction and 17 (30.9%) had both problems. Of the 67 (41+26) patients with abnormal neurophysiological outcomes, 51 (76.1%) with abnormal bulbocavernosus re?ex (BCR), 20 (29.9%) with pathological pudendal nerve evoked potentials (PDEPs) and 25 (37.3%) with abnormal posterior tibial somatosensory nerve evoked potentials (PTSSEPs). Our observation indicated that neurogenic factors are important for the generation of ED in patients with pelvic fracture; venous impotence is more common than arteriogenic ED.

Evolution of plant conducting cells: perspectives from key regulators of vascular cell differentiation.

PubMed

Ohtani, Misato; Akiyoshi, Nobuhiro; Takenaka, Yuto; Sano, Ryosuke; Demura, Taku

2017-01-01

One crucial problem that plants faced during their evolution, particularly during the transition to growth on land, was how to transport water, nutrients, metabolites, and small signaling molecules within a large, multicellular body. As a solution to this problem, land plants developed specific tissues for conducting molecules, called water-conducting cells (WCCs) and food-conducting cells (FCCs). The well-developed WCCs and FCCs in extant plants are the tracheary elements and sieve elements, respectively, which are found in vascular plants. Recent molecular genetic studies revealed that transcriptional networks regulate the differentiation of tracheary and sieve elements, and that the networks governing WCC differentiation are largely conserved among land plant species. In this review, we discuss the molecular evolution of plant conducting cells. By focusing on the evolution of the key transcription factors that regulate vascular cell differentiation, the NAC transcription factor VASCULAR-RELATED NAC-DOMAIN for WCCs and the MYB-coiled-coil (CC)-type transcription factor ALTERED PHLOEM DEVELOPMENT for sieve elements, we describe how land plants evolved molecular systems to produce the specialized cells that function as WCCs and FCCs. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Pancreatic transection from blunt trauma associated with vascular and biliary lesions: A case report

PubMed Central

Baiocchi, Gian Luca; Tiberio, Guido AM; Gheza, Federico; Gardani, Marco; Cantù, Massimiliano; Portolani, Nazario; Giulini, Stefano Maria

2008-01-01

Major injuries of the pancreas may result in considerable morbidity and mortality when associated with vascular and visceral injuries. In such cases, a right diagnosis and a prompt surgical intervention are necessary to give a chance to the patient. We herein describe a case of blunt abdominal trauma in a 29-year-old man whose pancreatic rupture was associated with hepatic artery, splenic vein and extrahepatic bile duct damage. Immediate surgery was performed after computer tomography (CT), the haemorrhagic lesions dictate the emergency transfer to the operating room. Spleno-pancreatic resection was done with reconstruction of the hepatic artery, ligation of the splenic vein and a Roux-en-Y bilio-jejunal diversion. The early post-operative course was complicated by stenosis of the arterial reconstruction, which was treated by endovascular angioplasty followed by percutaneous drainage of symptomatic pseudocyst, rest and antibiotics. Finally, the patient was discharged and was alive without clinical problems at the time when we wrote this case report. The present case underlines the clinical relevance of vascular and visceral injuries associated with pancreatic trauma and the problems arising in the diagnostic evaluation and the surgical strategy of complex multiple visceral and vascular lesions in blunt abdominal trauma. PMID:18720548

The clinical and cost-effectiveness of the BRinging Information and Guided Help Together (BRIGHT) intervention for the self-management support of people with stage 3 chronic kidney disease in primary care: study protocol for a randomized controlled trial

PubMed Central

2013-01-01

Background Improving the quality of care for people with vascular disease is a key priority. Chronic kidney disease (CKD) has recently been included as a target condition for general practices to add to registers of chronic conditions as part of the Quality and Outcome Framework. This paper outlines the implementation and evaluation of a self-management intervention involving an information guidebook, tailored access to local resources and telephone support for people with stage 3 chronic kidney disease. Methods/Design The study involves a multi-site, longitudinal patient-level randomized controlled trial. The study will evaluate the clinical use and cost-effectiveness of a complex self-management intervention for people with stage 3 chronic kidney disease in terms of self-management capacity, health-related quality of life and blood pressure control compared to care as usual. We describe the methods of the patient-level randomized controlled trial. Discussion The management of chronic kidney disease is a developing area of research. The BRinging Information and Guided Help Together (BRIGHT) trial aims to provide evidence that a complementary package of support for people with vascular disease that targets both clinical and social need broadens the opportunities of self-management support by addressing problems related to social disadvantage. Trial registration Trial registration reference: ISRCTN45433299 PMID:23356861

Accessing key steps of human tumor progression in vivo by using an avian embryo model

NASA Astrophysics Data System (ADS)

Hagedorn, Martin; Javerzat, Sophie; Gilges, Delphine; Meyre, Aurélie; de Lafarge, Benjamin; Eichmann, Anne; Bikfalvi, Andreas

2005-02-01

Experimental in vivo tumor models are essential for comprehending the dynamic process of human cancer progression, identifying therapeutic targets, and evaluating antitumor drugs. However, current rodent models are limited by high costs, long experimental duration, variability, restricted accessibility to the tumor, and major ethical concerns. To avoid these shortcomings, we investigated whether tumor growth on the chick chorio-allantoic membrane after human glioblastoma cell grafting would replicate characteristics of the human disease. Avascular tumors consistently formed within 2 days, then progressed through vascular endothelial growth factor receptor 2-dependent angiogenesis, associated with hemorrhage, necrosis, and peritumoral edema. Blocking of vascular endothelial growth factor receptor 2 and platelet-derived growth factor receptor signaling pathways by using small-molecule receptor tyrosine kinase inhibitors abrogated tumor development. Gene regulation during the angiogenic switch was analyzed by oligonucleotide microarrays. Defined sample selection for gene profiling permitted identification of regulated genes whose functions are associated mainly with tumor vascularization and growth. Furthermore, expression of known tumor progression genes identified in the screen (IL-6 and cysteine-rich angiogenic inducer 61) as well as potential regulators (lumican and F-box-only 6) follow similar patterns in patient glioma. The model reliably simulates key features of human glioma growth in a few days and thus could considerably increase the speed and efficacy of research on human tumor progression and preclinical drug screening. angiogenesis | animal model alternatives | glioblastoma

Imaging Metastasis Using an Integrin-Targeting Chain-Shaped Nanoparticle

PubMed Central

Peiris, Pubudu M.; Toy, Randall; Doolittle, Elizabeth; Pansky, Jenna; Abramowski, Aaron; Tam, Morgan; Vicente, Peter; Tran, Emily; Hayden, Elliott; Camann, Andrew; Mayer, Aaron; Erokwu, Bernadette O.; Berman, Zachary; Wilson, David; Baskaran, Harihara; Flask, Chris A.; Keri, Ruth A.; Karathanasis, Efstathios

2012-01-01

While the enhanced permeability and retention effect may promote the preferential accumulation of nanoparticles into well-vascularized primary tumors, it is ineffective in the case of metastases hidden within a large population of normal cells. Due to their small size, high dispersion to organs, and low vascularization, metastatic tumors are less accessible to targeted nanoparticles. To tackle these challenges, we designed a nanoparticle for vascular targeting based on an αvβ3 integrin-targeted nanochain particle composed of four iron oxide nanospheres chemically linked in a linear assembly. The chain-shaped nanoparticles enabled enhanced ‘sensing’ of the tumor-associated remodeling of the vascular bed offering increased likelihood of specific recognition of metastatic tumors. Compared to spherical nanoparticles, the chain-shaped nanoparticles resulted in superior targeting of αvβ3 integrin due to geometrically enhanced multivalent docking. We performed multimodal in vivo imaging (Fluorescence Molecular Tomography and Magnetic Resonance Imaging) in a non-invasive and quantitative manner, which showed that the nanoparticles targeted metastases in the liver and lungs with high specificity in a highly aggressive breast tumor model in mice. PMID:23005348

Flora-On: Occurrence data of the vascular flora of mainland Portugal.

PubMed

Pereira, Ana Júlia; Francisco, Ana; Porto, Miguel

2016-01-01

The Flora-On dataset currently includes 253,310 occurrence records for the class Embryopsidae (vascular plants), comprising data collated via the platform http://flora-on.pt/ relating to observation records of vascular plants across mainland Portugal. Observations are uploaded directly to the database primarily by experienced botanists and naturalists, typically on a weekly basis, and consist of geo-referenced data points for species (or infraspecific taxa) along with their date of observation and phenological state. The Flora-On project aims to compile and make publicly accessible chorological, ecological, morphological and photographic information for the entire vascular flora of Portugal. The project's website offers powerful query and visualization capabilities, of which we highlight the probabilistic bioclimatic and phenological queries which operate based on the empirical density distributions of species in those variables. Flora-On was created and continues to be maintained by volunteers who are Associate members of Sociedade Portuguesa de Botânica (Botanical Society of Portugal). Given its focus on research-grade and current data, the Flora-On project represents a significant contribution to the knowledge of the present distribution and status of the Portuguese flora.

Vascular Abnormalities Associated with Thermal and Electrical Trauma,

DTIC Science & Technology

1992-01-01

Knippenberg, R,W.: Temporal relationships among immunologic alterations in a guinea pig model of thermal injury. J. Infect, Dis., 153:1098, 1986. 7...decompression venous access to 72 hr in thermally injured patients of the stomach and alimentation provided either by is supported by the documented

Emergency sternal intraosseous access for warm fresh whole blood transfusion in damage control resuscitation.

PubMed

Bjerkvig, Christopher Kalhagen; Fosse, Theodor Kaurin; Apelseth, Torunn Oveland; Sivertsen, Joar; Braathen, Hanne; Eliassen, Håkon Skogrand; Guttormsen, Anne Berit; Cap, Andrew P; Strandenes, Geir

2018-06-01

Intraosseous (IO) vascular access is increasingly used as an emergency tool for achieving access to the systemic circulation in critically ill patients. The role of IO transfusion of blood in damage control resuscitation is however questionable due to possible inadequate flow rate and hemolysis. Some experts claim that IO transfusion is contraindicated. In this study, we have challenged this statement by looking at flow rates of autologous fresh whole blood reinfusion and hemolysis using two of the commonly used Food and Drug Administration-approved and Conformité Européenne (CE)-marked sternal needles. Additionally, the success rate of sternal access between the two devices is evaluated. Volunteer professional military personnel, were enrolled prospectively in a nonrandomized observational study design. We collected 450 mL of autologous whole blood from each participant. Participants were divided into the following three groups of 10: Tactically Advanced Lifesaving IO Needle (T.A.L.O.N.) IO, FAST1 IO, and intravenous group. The reinfusion was done by gravity only. Blood sampling was performed before blood collection and 30 minutes after reinfusion. Investigation of hemolysis was performed by measurements of haptoglobin and lactate dehydrogenase. Success rate was evaluated by correct aspiration of bone marrow. Median reinfusion rate was 46.2 mL/min in the FAST1 group, 32.4 mL/min in the T.A.L.O.N. group, and 74.1 mL/min in the intravenous group. Blood samples from all participants were within normal ranges. There was no statistically significant difference in haptoglobin and lactate dehydrogenase between the groups. In the FAST1 group, 1 (9%) of 11 procedures failed. In the T.A.L.O.N. group, 4 (29%) of 14 procedures failed. Although preferable, achieving peripheral venous access in the bleeding patient is a major problem. Our findings suggest that fresh whole-blood transfusion through the IO route is safe, reliable, and provide sufficient flow for resuscitation. Therapeutic/Care management study, level III.

The experience of foot problems and decisions to access foot care in patients with rheumatoid arthritis: a qualitative study.

PubMed

Wilson, Oonagh; Kirwan, John; Dures, Emma; Quest, Enid; Hewlett, Sarah

2017-01-01

Although foot problems are common in rheumatoid arthritis (RA), the consequences of foot problems from the patient perspective have not been fully explored. The aims of this study were to explore the experience of foot problems and decisions to access foot care services or not in patients with RA. Semi structured, one-to-one interviews with patients recruited from 2 UK rheumatology units, purposively sampled for self-reported foot problems and a range of personal/disease characteristics. Inductive thematic analysis was used, with rigour provided by multiple independent analysers. Emerging themes were discussed and agreed by all authors. Twelve patients participated: 7 female; mean age 56 years (29-72); mean disease duration 12 years (2-27), 5 had accessed foot care services. The 'Impact' of foot problems was substantial and formed the underpinning theme, comprising three organising themes: 'Foot symptoms'; 'Consequences'; and 'Cost'. Foot symptoms such as pain and numbness required self-management, and affected daily life (walking, working) leading to social and emotional costs. The global theme, 'Decision to access foot care or not', also comprised three organising themes: 'Access perceived unnecessary' (no problem, can cope); 'Access hindered by patients' perception'; and 'Access supported by patient and clinician'. Decisions to access foot care or not were complex and influenced by patient beliefs regarding possible treatments and how to access these, and hindered by patient perceptions that their feet were ignored by rheumatology clinicians. Positive experience of foot care encouraged continued utilisation but negative experiences contributed to patients' decisions to discontinue foot care services. Foot problems are important issues for patients and impact on many aspects of their physical, social and emotional lives. Patients who had accessed foot care services prioritised their foot problems as an important health care need. However, for others who would like foot care services, personal knowledge and values, and perceived barriers in clinical practice, appear to interact to inhibit foot care access. The extent which these interactions affect overall access to foot care in RA patients in general now needs to be quantified to help to inform and improve the effectiveness of the organisation and delivery of foot care.

Dialysis treatment in patients with rheumatoid arthritis.

PubMed

Hezemans, R L; Krediet, R T; Arisz, L

1995-07-01

The results of dialysis treatment in 24 rheumatoid arthritis patients, 20 chronic rheumatoid arthritis (RA) and 4 juvenile rheumatoid arthritis (JRA), were analysed. Presence of secondary amyloidosis, renal function, morbidity and survival were examined. Amyloidosis was present in 13 patients. Especially among amyloidosis patients, renal function declined rapidly in the last year before dialysis started. On average, 63 days per patient-year were spent in the hospital, 58% was dialysis-related, mainly due to vascular access problems. Hospitalization was even more widespread in amyloidosis patients (79 days, 72% dialysis-related). Median survival in RA patients with amyloidosis was 11 months; in RA patients without amyloidosis this was 29 months. Two-year survival was only 1 out of 10 for the RA amyloidosis patients; for the RA non-amyloidosis patients this was 5 out of 6 (p < 0.01). Cardiovascular causes of death were most frequent. In conclusion, high morbidity and low survival make RA patients with amyloidosis a high-risk group on renal replacement therapy.

Toward a full understanding of the EPR effect in primary and metastatic tumors as well as issues related to its heterogeneity.

PubMed

Maeda, Hiroshi

2015-08-30

The enhanced permeability and retention (EPR) effect of solid tumors as seen with nanomedicines and macromolecular drugs is well known. However, many researchers appear to lack a full understanding of this effect. The effect varies depending on a patient's pathological and physiological characteristics and clinical condition. When a patient's systolic blood pressure is low side of about 90mmHg instead of 120-130mmHg, the hydrodynamic force pushing blood from the luminal side of a vessel into tumor tissue becomes significantly low, which results in a low EPR. Also, a vascular embolism in a tumor may impede blood flow and the EPR. Here, I describe the background of the EPR effect, heterogeneity of this effect, physiological and pathological factors affecting the effect, the EPR effect in metastatic tumors, artifacts of the EPR effect with micellar and liposomal drugs, problems of macromolecular drug stability and drug release, and access to target sites. Copyright © 2015 Elsevier B.V. All rights reserved.

Dialysis in the elderly. New possibilities, new problems.

PubMed

Cassidy, M J D; Sims, R J A

2004-09-01

In the last 2 decades, there has been a phenomenal increase in the number of incident and prevalent elderly patients receiving renal replacement therapy (RRT) and this trend is likely to continue. This article reviews the changing demographics of the renal patient population and discusses the possible reasons for this. The profile of the older adult patient group is discussed, and specific demands and requirements of this patient group are explained. In particular, the authors concentrate on dialysis mode and vascular access; malnutrition; falls and fractures; cognitive impairment and depression and drugs and pain. It is clear that the ''old old'' can benefit significantly from dialysis despite an increasing burden of comorbidity and prognosis on dialysis is discussed. In order to properly inform patients about treatment options it is essential to provide information about prognosis. For some patients dialysis may not be the preferred option and for others withdrawal from dialysis may be appropriate. Nephrologists therefore also need to be familiar with end of life issues and palliative symptom control.

Risk factors, management and primary prevention of thrombotic complications related to the use of central venous catheters.

PubMed

Linnemann, Birgit; Lindhoff-Last, Edelgard

2012-09-01

An adequate vascular access is of importance for the treatment of patients with cancer and complex illnesses in the intensive, perioperative or palliative care setting. Deep vein thrombosis and thrombotic occlusion are the most common complications attributed to central venous catheters in short-term and, especially, in long-term use. In this review we will focus on the risk factors, management and prevention strategies of catheter-related thrombosis and occlusion. Due to the lack of randomised controlled trials, there is still controversy about the optimal treatment of catheter-related thrombotic complications, and therapy has been widely adopted using the evidence concerning lower extremity deep vein thrombosis. Given the increasing use of central venous catheters in patients that require long-term intravenous therapy, the problem of upper extremity deep venous thrombosis can be expected to increase in the future. We provide data for establishing a more uniform strategy for preventing, diagnosing and treating catheter-related thrombotic complications.

Epigenetic regulation of vascular smooth muscle cell function in atherosclerosis.

PubMed

Findeisen, Hannes M; Kahles, Florian K; Bruemmer, Dennis

2013-04-01

Epigenetics involve heritable and acquired changes in gene transcription that occur independently of the DNA sequence. Epigenetic mechanisms constitute a hierarchic upper-level of transcriptional control through complex modifications of chromosomal components and nuclear structures. These modifications include, for example, DNA methylation or post-translational modifications of core histones; they are mediated by various chromatin-modifying enzymes; and ultimately they define the accessibility of a transcriptional complex to its target DNA. Integrating epigenetic mechanisms into the pathophysiologic concept of complex and multifactorial diseases such as atherosclerosis may significantly enhance our understanding of related mechanisms and provide promising therapeutic approaches. Although still in its infancy, intriguing scientific progress has begun to elucidate the role of epigenetic mechanisms in vascular biology, particularly in the control of smooth muscle cell phenotypes. In this review, we will summarize epigenetic pathways in smooth muscle cells, focusing on mechanisms involved in the regulation of vascular remodeling.

Epigenetic regulation of vascular smooth muscle cell function in atherosclerosis.

PubMed

Findeisen, Hannes M; Kahles, Florian K; Bruemmer, Dennis

2013-05-01

Epigenetics involve heritable and acquired changes in gene transcription that occur independently of the DNA sequence. Epigenetic mechanisms constitute a hierarchic upper-level of transcriptional control through complex modifications of chromosomal components and nuclear structures. These modifications include, for example, DNA methylation or post-translational modifications of core histones; they are mediated by various chromatin-modifying enzymes; and ultimately they define the accessibility of a transcriptional complex to its target DNA. Integrating epigenetic mechanisms into the pathophysiologic concept of complex and multifactorial diseases such as atherosclerosis may significantly enhance our understanding of related mechanisms and provide promising therapeutic approaches. Although still in its infancy, intriguing scientific progress has begun to elucidate the role of epigenetic mechanisms in vascular biology, particularly in the control of smooth muscle cell phenotypes. In this review, we will summarize epigenetic pathways in smooth muscle cells, focusing on mechanisms involved in the regulation of vascular remodeling.

Publishing corruption discussion: predatory journalism.

PubMed

Jones, James W; McCullough, Laurence B

2014-02-01

Dr Spock is a brilliant young vascular surgeon who is up for tenure next year. He has been warned by the chair of surgery that he needs to increase his list of publications to assure passage. He has recently had a paper reviewed by one of the top journals in his specialty, Journal X-special, with several suggestions for revision. He received an e-mail request for manuscript submission from a newly minted, open access, Journal of Vascular Disease Therapy, which promises a quick and likely favorable response for a fee. What should be done? A. Send the paper to another peer reviewed journal with the suggested revisions. B. Resubmit the paper to Journal X-special. C. Submit to the online journal as is to save time. D. Submit to the online journal and another regular journal. E. Look for another job. Copyright © 2014 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Open Problems in Computational Vascular Biomechanics: Hemodynamics and Arterial Wall Mechanics

PubMed Central

Taylor, C.A.; Humphrey, J.D.

2009-01-01

The vasculature consists of a complex network of vessels ranging from large arteries to arterioles, capillaries, venules, and veins. This network is vital for the supply of oxygen and nutrients to tissues and the removal of carbon dioxide and waste products from tissues. Because of its primary role as a pressure-driven chemomechanical transport system, it should not be surprising that mechanics plays a vital role in the development and maintenance of the normal vasculature as well as in the progression and treatment of vascular disease. This review highlights some past successes of vascular biomechanics, but emphasizes the need for research that synthesizes complementary advances in molecular biology, biomechanics, medical imaging, computational methods, and computing power for purposes of increasing our understanding of vascular physiology and pathophysiology as well as improving the design of medical devices and clinical interventions, including surgical procedures. That is, computational mechanics has great promise to contribute to the continued improvement of vascular health. PMID:20161129

Is Team-Based Primary Care Associated with Less Access Problems and Self-Reported Unmet Need in Canada?

PubMed

Zygmunt, Austin; Asada, Yukiko; Burge, Frederick

2017-10-01

As in many jurisdictions, the delivery of primary care in Canada is being transformed from solo practice to team-based care. In Canada, team-based primary care involves general practitioners working with nurses or other health care providers, and it is expected to improve equity in access to care. This study examined whether team-based care is associated with fewer access problems and less unmet need and whether socioeconomic gradients in access problems and unmet need are smaller in team-based care than in non-team-based care. Data came from the 2008 Canadian Survey of Experiences with Primary Health Care (sample size: 10,858). We measured primary care type as team-based or non-team-based and socioeconomic status by income and education. We created four access problem variables and four unmet need variables (overall and three specific components). For each, we ran separate logistic regression models to examine their associations with primary care type. We examined socioeconomic gradients in access problems and unmet need stratified by primary care type. Primary care type had no statistically significant, independent associations with access problems or unmet need. Among those with non-team-based care, a statistically significant education gradient for overall access problems existed, whereas among those with team-based care, no statistically significant socioeconomic gradients existed.

Use of vascular access ports in femoral veins of dogs and cats with cancer.

PubMed

Cahalane, Alane Kosanovich; Rassnick, Kenneth M; Flanders, James A

2007-11-01

To evaluate long-term function of vascular access ports (VAPs) implanted in the femoral vein of dogs and cats undergoing cancer treatment. Prospective clinical study. 3 dogs and 6 cats treated via chemotherapy or radiation. VAPs were surgically implanted in the left femoral vein of 3 dogs and 6 cats over a 1-year period. Injection port location was alternated to either a caudal thoracic or ilial location in each patient. Duration of VAP function, ease of infusion, and ease of aspiration through the VAPs were recorded, and associated complications were assessed at each VAP use. Client satisfaction with VAP placement was evaluated by use of a questionnaire. Primary uses of the VAPs included blood sampling and delivering sedative or chemotherapeutic drugs. Median duration of successful infusion was 147 days (range, 60 to 370 days), and median duration of successful aspiration was 117 days (range, 10 to 271 days). The frequency of signs of VAP-related discomfort was low (7% of patient observations). Clients were satisfied with their decision to use VAPs. Complications included partial (n = 7) or complete (2) VAP occlusion, port migration (1), and presumptive infection (1). Results suggested that VAP implantation into the femoral vein provides an acceptable means of chronic venous access in dogs and cats undergoing cancer treatment.

Central Venous Occlusion in the Hemodialysis Patient.

PubMed

Krishna, Vinay Narasimha; Eason, Joseph B; Allon, Michael

2016-11-01

Central venous stenosis (CVS) is encountered frequently among hemodialysis patients. Prior ipsilateral central venous catheterization and cardiac rhythm device insertions are common risk factors, but CVS can also occur in the absence of this history. Chronic CVS can cause thrombosis with partial or complete occlusion of the central vein at the site of stenosis. CVS is frequently asymptomatic and identified as an incidental finding during imaging studies. Symptomatic CVS presents most commonly as an upper- or lower-extremity edema ipsilateral to the CVS. Previously unsuspected CVS may become symptomatic after placement of an ipsilateral vascular access. The likelihood of symptomatic CVS may be affected by the central venous catheter (CVC) location; CVC side; duration of CVC dependence; type, location, and blood flow of the ipsilateral access; and extent of collateral veins. Venous angiography is the gold standard for diagnosis. Percutaneous transluminal angioplasty and stent placement can improve the stenosis and alleviate symptoms, but CVS typically recurs frequently, requiring repeated interventions. Refractory symptomatic CVS may require ligation of the ipsilateral vascular access. Because no available treatment option is curative, the goal should be to prevent CVS by minimizing catheters and central vein instrumentation in patients with chronic kidney disease and dialysis patients. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

MOrtality and infectious complications of therapeutic EndoVAscular interventional radiology: a systematic and meta-analysis protocol.

PubMed

Mellouk Aid, Kaoutar; Tchala Vignon Zomahoun, Hervé; Soulaymani, Abdelmajid; Lebascle, Karin; Silvera, Stephane; Astagneau, Pascal; Misset, Benoit

2017-04-24

Endovascular interventional radiology (EIR) is an increasingly popular, mini invasive treatment option for patient with symptomatic vascular disease. The EIR practiced by qualified hands is an effective, well-tolerated procedure that offers relief of patient's symptoms with a low risk of complications. During acute post procedural period, immediate complications may relate to vascular access, restenosis, thromboembolic events, uterine ischemia, infection, necrosis, sepsis, ICU stay, surgical recovery, pain management, treatment failure, and death. Moreover, additional non-life-threatening complications exist, but they are not well described and represent disparate information. A range of databases will be screened consulted to identify the relevant studies: PubMed, EMBASE, The Cochrane Library, NosoBase, and Google Scholar (to identify articles not yet indexed). Scientist librarian used Medical Subject Headings (MeSH) and free terms to construct the search strategy in PubMed. This search strategy will be adapted in other databases. Two coauthors will independently select the relevant studies, extract the relevant data, and assess the risk of bias in the included studies. Any disagreements between the two authors will be solved by a third author. This systematic review will provide a synthesis of EIR complications. The spotlighted results will be analyzed in order to provide a state-of-knowledge synopsis of the current evidence base in relation to the epidemiology of the infectious complications after EIR. In the event of conclusive results, our findings will serve as a reference background to assess guidelines on reality of the problem of the infections linked to endovascular interventional radiology and to formulate of assumptions and propose preventive measures, based on the results of our investigations. These propositions will aim to reduce the risk and/or the severity of these complications in the concerned population in favor a positive medical economics report. It will also aim to decrease the antibio-resistance and in fine will improve health status and security of patients. PROSPERO CRD42015025594.

Dual labeling of neural crest cells and blood vessels within chicken embryos using Chick(GFP) neural tube grafting and carbocyanine dye DiI injection.

PubMed

Delalande, Jean-Marie; Thapar, Nikhil; Burns, Alan J

2015-05-28

All developing organs need to be connected to both the nervous system (for sensory and motor control) as well as the vascular system (for gas exchange, fluid and nutrient supply). Consequently both the nervous and vascular systems develop alongside each other and share striking similarities in their branching architecture. Here we report embryonic manipulations that allow us to study the simultaneous development of neural crest-derived nervous tissue (in this case the enteric nervous system), and the vascular system. This is achieved by generating chicken chimeras via transplantation of discrete segments of the neural tube, and associated neural crest, combined with vascular DiI injection in the same embryo. Our method uses transgenic chick(GFP) embryos for intraspecies grafting, making the transplant technique more powerful than the classical quail-chick interspecies grafting protocol used with great effect since the 1970s. Chick(GFP)-chick intraspecies grafting facilitates imaging of transplanted cells and their projections in intact tissues, and eliminates any potential bias in cell development linked to species differences. This method takes full advantage of the ease of access of the avian embryo (compared with other vertebrate embryos) to study the co-development of the enteric nervous system and the vascular system.

The Soil-Plant-Atmosphere System - Past and Present.

NASA Astrophysics Data System (ADS)

Berry, J. A.; Baker, I. T.; Randall, D. A.; Sellers, P. J.

2012-12-01

Plants with stomata, roots and a vascular system first appeared on earth about 415 million years ago. This evolutionary innovation helped to set in motion non-linear feedback mechanisms that led to an acceleration of the hydrologic cycle over the continents and an expansion of the climate zones favorable for plant (and animal) life. Skeletal soils that developed long before plants came onto the land would have held water and nutrients in their pore space, yet these resources would have been largely unavailable to primitive, surface-dwelling non-vascular plants due to physical limitations on water transport once the surface layer of soil dries. Plants with roots and a vascular system that could span this dry surface layer could gain increased and prolonged access to the water and nutrients stored in the soil for photosynthesis. Maintenance of the hydraulic connections permitting water to be drawn through the vascular system from deep in the soil to the sites of evaporation in the leaves required a cuticle and physiological regulation of stomata. These anatomical and physiological innovations changed properties of the terrestrial surface (albedo, roughness, a vascular system and control of surface conductance) and set in motion complex interactions of the soil - plant - atmosphere system. We will use coupled physiological and meteorological models to examine some of these interactions.

Dual Labeling of Neural Crest Cells and Blood Vessels Within Chicken Embryos Using ChickGFP Neural Tube Grafting and Carbocyanine Dye DiI Injection

PubMed Central

Delalande, Jean-Marie; Thapar, Nikhil; Burns, Alan J.

2015-01-01

All developing organs need to be connected to both the nervous system (for sensory and motor control) as well as the vascular system (for gas exchange, fluid and nutrient supply). Consequently both the nervous and vascular systems develop alongside each other and share striking similarities in their branching architecture. Here we report embryonic manipulations that allow us to study the simultaneous development of neural crest-derived nervous tissue (in this case the enteric nervous system), and the vascular system. This is achieved by generating chicken chimeras via transplantation of discrete segments of the neural tube, and associated neural crest, combined with vascular DiI injection in the same embryo. Our method uses transgenic chickGFP embryos for intraspecies grafting, making the transplant technique more powerful than the classical quail-chick interspecies grafting protocol used with great effect since the 1970s. ChickGFP-chick intraspecies grafting facilitates imaging of transplanted cells and their projections in intact tissues, and eliminates any potential bias in cell development linked to species differences. This method takes full advantage of the ease of access of the avian embryo (compared with other vertebrate embryos) to study the co-development of the enteric nervous system and the vascular system. PMID:26065540

Cardiovascular Bio-Engineering: Current State of the Art.

PubMed

Simon-Yarza, Teresa; Bataille, Isabelle; Letourneur, Didier

2017-04-01

Despite the introduction of new drugs and innovative devices contributing in the last years to improve patients' quality of life, morbidity and mortality from cardiovascular diseases remain high. There is an urgent need for addressing the underlying problem of the loss of cardiac or vascular tissues and therefore developing new therapies. Autologous vascular transplants are often limited by poor quality of donor sites and heart organ transplantation by donor shortage. Vascular and cardiac tissue engineering, whose aim is to repair or replace cardiovascular tissues by the use of cells, engineering and materials, as well as biochemical and physicochemical factors, appears in this scenario as a promising tool to repair the damaged hearts and vessels. We will present a general overview on the fundamentals in the area of cardiac and vascular tissue engineering as well as on the latest progresses and challenges.

Successful Endovascular Control of Renal Artery in a Transplant Kidney During Nephron Sparing Surgery (NSS) for Large Centrally Located Tumor.

PubMed

Shprits, Sagi; Moskovits, Boaz; Sachner, Robert; Nativ, Ofer

2016-05-01

Renal cell carcinoma in a transplant kidney is a rare condition. Nephron Sparing Surgery (NSS) is the treatment of choice. One of the main technical challenges is obtaining adequate vascular control. We present a rare case of large centrally located hillar tumor in a kidney 18 years after transplantation treated with NSS. Vascular control was achieved by using a novel approach. Post-operative course was uneventful with minimal decrease in renal function. We believe that this unique choice of treatment can be used in cases of NSS where the access to the renal pedicle is limited.

Transarterial Embolization of a Spontaneous Intraorbital Arteriovenous Fistula With n-BCA Glue.

PubMed

Konstas, Angelos A; Rootman, Daniel B; Quiros, Peter A; Ross, Ian B

Arteriovenous fistulae of the orbit are exceedingly rare. They are high-flow vascular malformations involving a fistula from the ophthalmic artery to one of the draining ophthalmic veins. Presenting symptoms can mimic those of carotid cavernous fistulae or of ophthalmic venous varices, and include diplopia, proptosis, chemosis, decreased visual acuity, and retro-orbital pain. Very few case reports are published on the treatment of this aggressive vascular malformation, and they uniformly describe techniques involving a transvenous access for the embolization of the fistula. To the best of authors' knowledge, they report the first case of transarterial embolization of an intraorbital AVF.

Vascular surgical education in a medium-income country.

PubMed

Abdool-Carrim, A T O; Veller, M G

2010-03-01

Medium income country such as South Africa face a dilemma on the need to offer high quality vascular surgical care in a resource constrained environment, where the vast majority of population has inadequate access to even the most basic health care provision. At the same time with rapid development in technology there is also the need to provide high technological treatment to a small population that can afford high cost therapy. This apparent dichotomy in health care provides a challenge and the solution is for all role players in the health care provision to find a solution which will suite the population at large.

Gambling involvement and increased risk of gambling problems.

PubMed

Phillips, James G; Ogeil, Rowan; Chow, Yang-Wai; Blaszczynski, Alex

2013-12-01

The opportunity to gamble has undergone rapid expansion with technology allowing for access to gambling products 24 h a day. This increased online availability challenges governments' abilities to restrict access to gambling. Indeed, the ready access to multiple forms of gambling may potentially contribute to impaired control over urges for problem gamblers. The present study considered whether problem gamblers manifested a tendency to engage in multiple forms of gambling and identified forms of gambling which were more strongly related to problem gambling. In reanalyses of two surveys (Sample 1, N = 464, Sample 2, N = 1141), significant relationships accounting for between 11.3 and 13.5% of the variance were found between the numbers of forms of gambling accessed and degree of problem. Participation in online poker, playing cards and sports wagering were linked to problem gambling. Access to multiple forms of gambling may pose difficulties for the tracking and control of gambling.

Support Services for Remote Users of Online Public Access Catalogs.

ERIC Educational Resources Information Center

Kalin, Sally W.

1991-01-01

Discusses the needs of remote users of online public access catalogs (OPACs). User expectations are discussed; problems encountered by remote-access users are examined, including technical problems and searching problems; support services are described, including instruction, print guides, and online help; and differences from the needs of…

Effect of Vascular Access Site Choice on Radiation Exposure During Coronary Angiography: The REVERE Trial (Randomized Evaluation of Vascular Entry Site and Radiation Exposure).

PubMed

Pancholy, Samir B; Joshi, Pankaj; Shah, Sanjay; Rao, Sunil V; Bertrand, Olivier F; Patel, Tejas M

2015-08-17

This study sought to perform a randomized noninferiority trial of radiation exposure during cardiac catheterization comparing femoral access (FA) with left radial access (LRA) and right radial access (RRA). Increased radiation exposure with radial approach compared with femoral approach remains a controversial issue. This study randomized 1,493 patients undergoing cardiac catheterization at a tertiary care center to FA, LRA, and RRA in a 1:1:1 fashion. The primary endpoint was air kerma. The secondary endpoints included dose-area product, fluoroscopy time and operator dose per procedure, number of cineangiograms, and number of catheters. Baseline and procedural characteristics were similar among groups. No significant differences were observed in air kerma (medians: FA: 421 mGy [interquartile range (IQR): 337 to 574 mGy], LRA: 454 mGy [IQR: 331 to 643 mGy], and RRA: 483 mGy [IQR: 382 to 592 mGy], p = 0.146), dose-area product (medians: FA: 25.5 Gy cm(2) [IQR: 19.6 to 34.5 Gy cm(2)], LRA: 26.6 Gy cm(2) [IQR: 19.5 to 37.5 Gy cm(2)], and RRA: 27.7 Gy cm(2) [IQR: 21.9 to 34.4 Gy cm(2)], p = 0.40), or fluoroscopy time (medians: FA: 1.3 min [IQR: 1.0 to 1.7 min], LRA: 1.3 min [IQR: 1.0 to 1.7 min], and RRA: 1.32 min [IQR: 1.0 to 1.7 min], p = 0.19) among the 3 access sites. Median operator exposure was higher in the LRA group (3 mrem [IQR: 2 to 5 mrem], p = 0.001 vs. FA, and p = 0.0001 vs. RRA) compared with the FA (2 mrem [IQR: 2 to 4 mrem] and RRA groups (3 mrem [IQR: 2 to 5 mrem]). Radiation exposure to patients was similar during diagnostic coronary angiography with FA, RRA, and LRA. However, LRA was associated with significantly higher operator radiation exposure than were FA and RRA procedures. (Randomized Evaluation of Vascular Entry Site and Radiation Exposure [REVERE]; NCT01677481). Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Use of a biodegradable, oversized stent in a child with tracheomalacia secondary to vascular external compression.

PubMed

Di Dedda, Giovanni; Mirabile, Cristian

2017-01-01

We describe the implantation of an absorbable, custom-made stent of polydioxanone to treat tracheomalacia in a 5-month-old patient with extrinsic compression by a double aortic arch. The use of an absorbable, oversized stent treated the tracheal collapse caused by vascular compression, avoided removal procedures, and allowed the infant's growth. The use of an oversized stent prevented stent migration and gave minimal problems of granulation.

GVHD (Graft-Versus-Host Disease): A Guide for Patients and Families After Stem Cell Transplant

MedlinePlus

... the first 100 days after your transplant or infusion of T-cells (in a donor lymphocyte infusion, or DLI). Acute GVHD commonly affects your skin, ... mouth or put on your skin or an infusion through a vascular access device. Also, treatment may ...

A vascular disease educational program in the preclinical years of medical school increases student interest in vascular disease.

PubMed

Godshall, Christopher J; Moore, Phillip S; Fleming, Shawn H; Andrews, Jeanette S; Hansen, Kimberley J; Hoyle, John R; Edwards, Matthew S

2010-09-01

New training paradigms in vascular surgery necessitate medical student interest in vascular disease. We examined the effects of incorporation of a vascular disease educational program during the second year of the medical school curriculum on student acquisition of knowledge and interest in the treatment of vascular disease. We developed and administered a new educational program on vascular disease and delivered the program to all second-year medical students. The new program encompassed 9 didactic hours, including 7 traditional lecture hours and 2 hours of problem-based learning. After completing the program, students were surveyed regarding vascular disease-specific knowledge, interest in treating vascular disease, and career choices. Third-year students who were not exposed to the program were surveyed as a control group. We recorded the voluntary student enrollment in the vascular and endovascular surgery rotation during the following academic year. Voluntary enrollment of the students exposed to the vascular disease education program was compared with enrollment for the previous 8 years. Before the introduction of the new educational program, 946 total lecture hours were delivered to first- and second-year medical students, comprising 490 hours (52%) given by nonsurgeon physicians, 445 (47%) by nonphysicians, and 11 (1%) by surgeons. Survey response rate was 93% (112 of 121) for second-year students and 95% (39 of 41) for third-year students. After the vascular disease program, second-year students answered 7.1 +/- 1.4 of 9 vascular disease questions correctly, whereas unexposed third-year students answered 7.2 +/- 1.7 questions correctly (P = .96). Most second-year medical students described a "somewhat" or "much greater" interest in the medical (63%), procedural (59%), and overall (63%) management of vascular disease after exposure to the program. Most also had a "somewhat" or "much greater" interest in a vascular medicine (64%) or vascular and endovascular surgery (60%) rotation. Enrollment in the vascular surgery third-year clerkship increased significantly to a mean of 3.0 students/month from 1.16 students/month in the prior year (P = .0032, postintervention year vs 8 prior years). A vascular disease educational program administered to second-year medical students increases interest in vascular disease and interest in further training. The increased interest translates to greater student enrollment in the vascular surgery clerkship in the subsequent academic year.

Principles of definitive soft tissue coverage with flaps.

PubMed

Levin, L Scott

2008-01-01

Despite the emergence of negative pressure wound therapy with reticulated open cell foam (NPWT/ROCF) as delivered by V.A.C.(R) Therapy (KCI, San Antonio, TX) for orthopaedic trauma, vascularized tissue transfer whether it be pedicle, free, or tissue transfer using the operating microscope or as an island, remains the mainstay of soft tissue reconstruction for orthopaedic traumatology. The critisism of microvascular procedures has been that they are lengthy, costly, and required technical expertise to perform. While technical skills are required, microsurgical care has evolved into a routine operation with high degrees of success in experienced hand. The problem that still remains is access to surgeons who are interested in soft tissue reconstruction and can perform definitive coverage with flaps. There is a need in the orthopaedic community to solve the problem of lack of flap surgeons and as a result, NPWT/ROCF has been touted as the answer to flap reconstruction. NPWT/ROCF is an important addition to soft tissue reconstruction but it serves as a bridge rather than definitive coverage in many hands. Just as wound technology is evolving with tissue substitutes, growth factors and NPWT/ROCF flaps technology continues to advance with new perforator flaps and local regional flaps, particularly the sural flap, coming on line as mainstays of soft tissue reconstruction.

Percutaneous closure of patent foramen ovale without echocardiographic guidance.

PubMed

Jamshidi, Peiman; Wahl, Andreas; Windecker, Stephan; Schwerzmann, Markus; Seiler, Christian; Meier, Bernhard

2007-01-01

A percutaneous patent foramen ovale (PFO) closure procedure includes transesophageal or intracardiac echocardiographic guidance at many centers. We investigated the feasibility and complications of the PFO closure without echocardiography. A total of 420 consecutive patients (185 women and 235 men, mean age 51 +/- 12 years) underwent percutaneous PFO closure without echocardiographic guidance using 7 different devices. Of these, 106 patients (25%) had an associated atrial septal aneurysm. The implantation was successful in 418 patients (99%). There were 12 procedural complications (3%), including embolization of the device or of parts of it with successful percutaneous removal in 5 cases, pericardial tamponade requiring pericardiocentesis in 1 patient, air embolism with transient symptoms in 3 patients, and vascular access problems in 3 patients. In none of the cases, echocardiography had to be summoned during the case or its lack was associated with acute or subsequent problems. The fluoroscopy time and procedure time were 5.4 +/- 2.7 and 25 +/- 17 minutes, respectively. Transthoracic contrast echocardiography, 24 hours after device implantation, detected a residual shunt in 19% of the patients. Percutaneous PFO closure with fluoroscopic guidance only is feasible and has low complication rates, especially with Amplatzer PFO Occluders. The added time and cost of echocardiography during the procedure is not warranted.

Breakout session: Ethnic and gender differences in diabetic foot management and amputations.

PubMed

Johnson, Anthony E; Lavernia, Carlos

2011-07-01

Although the health status of all Americans has improved substantially in the past century, gender and ethnic disparities still persist. Gender and ethnic disparities in diabetic foot management and amputations are an important but largely ignored issue in musculoskeletal health care. Our purposes were to (1) clarify where we are now, (2) describe ways to get where we need to go, and (3) suggest solutions for how we get there, with respect to gender and ethnic disparities in diabetic foot management and amputations. WHERE ARE WE NOW?: Studies investigating socioeconomic, cultural, racial, and biologic contributing factors on gender and ethnic musculoskeletal healthcare disparities have found no single root cause. Studies into disparities in diabetic foot management and amputation have discordant methodologies and most are retrospective. Effective intervention strategies to eliminate these disparities are nonexistent. WHERE DO WE NEED TO GO?: The orthopaedic leadership should lead the movement to create a clearly defined strategy and assist young investigators to gain access to large datasets to study this problem. Orthopaedic specialty society leaders should help to create valid outcome tools, especially on peripheral vascular disease and amputations. HOW DO WE GET THERE?: The working group proposed a three-pronged strategy of education, research, and advocacy to help address this problem.

Integrated approaches to spatiotemporally directing angiogenesis in host and engineered tissues.

PubMed

Kant, Rajeev J; Coulombe, Kareen L K

2018-03-15

The field of tissue engineering has turned towards biomimicry to solve the problem of tissue oxygenation and nutrient/waste exchange through the development of vasculature. Induction of angiogenesis and subsequent development of a vascular bed in engineered tissues is actively being pursued through combinations of physical and chemical cues, notably through the presentation of topographies and growth factors. Presenting angiogenic signals in a spatiotemporal fashion is beginning to generate improved vascular networks, which will allow for the creation of large and dense engineered tissues. This review provides a brief background on the cells, mechanisms, and molecules driving vascular development (including angiogenesis), followed by how biomaterials and growth factors can be used to direct vessel formation and maturation. Techniques to accomplish spatiotemporal control of vascularization include incorporation or encapsulation of growth factors, topographical engineering, and 3D bioprinting. The vascularization of engineered tissues and their application in angiogenic therapy in vivo is reviewed herein with an emphasis on the most densely vascularized tissue of the human body - the heart. Vascularization is vital to wound healing and tissue regeneration, and development of hierarchical networks enables efficient nutrient transfer. In tissue engineering, vascularization is necessary to support physiologically dense engineered tissues, and thus the field seeks to induce vascular formation using biomaterials and chemical signals to provide appropriate, pro-angiogenic signals for cells. This review critically examines the materials and techniques used to generate scaffolds with spatiotemporal cues to direct vascularization in engineered and host tissues in vitro and in vivo. Assessment of the field's progress is intended to inspire vascular applications across all forms of tissue engineering with a specific focus on highlighting the nuances of cardiac tissue engineering for the greater regenerative medicine community. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Dynamic Analysis of Vascular Morphogenesis Using Transgenic Quail Embryos

PubMed Central

Huss, David; Filla, Michael B.; Czirok, Andras; Rongish, Brenda J.; Little, Charles D.; Fraser, Scott E.; Lansford, Rusty

2010-01-01

Background One of the least understood and most central questions confronting biologists is how initially simple clusters or sheet-like cell collectives can assemble into highly complex three-dimensional functional tissues and organs. Due to the limits of oxygen diffusion, blood vessels are an essential and ubiquitous presence in all amniote tissues and organs. Vasculogenesis, the de novo self-assembly of endothelial cell (EC) precursors into endothelial tubes, is the first step in blood vessel formation [1]. Static imaging and in vitro models are wholly inadequate to capture many aspects of vascular pattern formation in vivo, because vasculogenesis involves dynamic changes of the endothelial cells and of the forming blood vessels, in an embryo that is changing size and shape. Methodology/Principal Findings We have generated Tie1 transgenic quail lines Tg(tie1:H2B-eYFP) that express H2B-eYFP in all of their endothelial cells which permit investigations into early embryonic vascular morphogenesis with unprecedented clarity and insight. By combining the power of molecular genetics with the elegance of dynamic imaging, we follow the precise patterning of endothelial cells in space and time. We show that during vasculogenesis within the vascular plexus, ECs move independently to form the rudiments of blood vessels, all while collectively moving with gastrulating tissues that flow toward the embryo midline. The aortae are a composite of somatic derived ECs forming its dorsal regions and the splanchnic derived ECs forming its ventral region. The ECs in the dorsal regions of the forming aortae exhibit variable mediolateral motions as they move rostrally; those in more ventral regions show significant lateral-to-medial movement as they course rostrally. Conclusions/Significance The present results offer a powerful approach to the major challenge of studying the relative role(s) of the mechanical, molecular, and cellular mechanisms of vascular development. In past studies, the advantages of the molecular genetic tools available in mouse were counterbalanced by the limited experimental accessibility needed for imaging and perturbation studies. Avian embryos provide the needed accessibility, but few genetic resources. The creation of transgenic quail with labeled endothelia builds upon the important roles that avian embryos have played in previous studies of vascular development. PMID:20856866

Pediatric Vascular Access Peripheral IV Algorithm Success Rate.

PubMed

Hartman, Jane H; Baker, John; Bena, James F; Morrison, Shannon L; Albert, Nancy M

Determine if the pediatric peripheral vascular access algorithm (PPVAA) led to differences in first-attempt and overall peripheral intravenous (PIV) success, staff attempting PIV access per episode and overall attempts and first PIV attempt success by provider. A two-cohort pre-/post-implementation comparative design involved pediatric nurses and patients. The PPVAA included four components: a patient comfort plan, PIV grading score, nurses' self-assessed IV access capability and nurse decision to stop-the-line. Two sample t-test or Wilcoxon rank sum test and Pearson's chi-square test were used to evaluate differences between groups and measures. Healthcare providers (N=96) attempted 721 PIV insertions (pre-PPVAA, n=419 and post-PPVAA, n=302). Of 78 nurse providers, mean (SD) age was 37.4 (11.0) years and 20.0% self-assessed PIV capability as expert. Of children, mean age was 8.3 (7.0) years. Post-PPVAA, first-attempt (p=0.86) and overall (p=0.21) success did not change, though fewer staff were needed per episode to initiate PIV; p=0.017. Overall rate of success after one attempt in the post-PPVAA period compared to pre-PPVAA was reduced (p=0.002), reflecting greater awareness to stop-the-line. Compared to pre-PPVAA, advanced practice nurses and non-clinician providers were more likely to achieve success on first attempt. The PPVAA did not increase first-attempt or overall PIV success; however, it decreased overall IV attempts and the number of staff attempting access per episode. The multi-component PPVAA provided a guide for nurses during PIV and assisted decision making to stop attempts in difficult cases. Copyright © 2017 Elsevier Inc. All rights reserved.

Starclose SE® hemostasis after 6F direct antegrade superficial femoral artery access distal to the femoral head for peripheral endovascular procedures in obese patients.

PubMed

Spiliopoulos, Stavros; Kitrou, Panagiotis; Christeas, Nikolaos; Karnabatidis, Dimitris

2016-01-01

Direct superficial femoral artery (SFA) antegrade puncture is a valid alternative to common femoral artery (CFA) access for peripheral vascular interventions. Data investigating vascular closure device (VCD) hemostasis of distant SFA 6F access are limited. We aimed to investigate the safety and effectiveness of the Starclose SE® VCD for hemostasis, following direct 6F antegrade SFA access distal to the femoral head. This prospective, single-center study included patients who were not suitable for CFA puncture and were scheduled to undergo peripheral endovascular interventions using direct antegrade SFA 6F access, at least 2 cm below the inferior edge of femoral head. Hemostasis was obtained with the Starclose SE® VCD (Abbott Laboratories). Primary endpoints were successful hemostasis rate and periprocedural (30-day) major complication rate. Secondary endpoint was the rate of minor complications. Clinical and Doppler ultrasound follow-up was performed at discharge and at one month. Between September 2014 and August 2015, a total of 30 patients (21 male; 70.0%) with a mean body mass index of 41.2 kg/m2 were enrolled. Mean age was 72±9 years (range, 67-88 years). Most patients suffered from critical limb ischemia (87.1%) and diabetes (61.3%). Calcifications were present in eight cases (26.6%). Reason for direct SFA puncture was obesity (100%). Successful hemostasis was achieved in 100% of the cases. No major complications were noted after one-month follow-up. Minor complications included two <5 cm hematomas (6.6%) not necessitating treatment. In this prospective study, Starclose SE® VCD was safe and effective for hemostasis of antegrade direct SFA puncture. Uncomplicated hemostasis was achieved even in cases of puncturing 2 to 7 cm below the inferior edge of the femoral head.

The 50 most influential original articles in vascular surgery during the last 25 years.

PubMed

Stegall, Frank; Corey, Michael; Dattilo, Jeffery

2014-09-01

We have compiled a list of the 50 most-cited original articles in the field of vascular surgery during the last 25 years to highlight the important changes in practice that have occurred during this interval and provide surgical trainees in vascular surgery ready access to such influential articles. A Web of Knowledge Citation Index Search was performed in December 2013 for the most-cited journal articles in the discipline of vascular surgery. We searched the term "vascular" in the cited reference search area and then further narrowed our results to exclude all categories except "surgery," "general internal medicine," and "cardiac/cardiovascular systems." We included only documents labeled as "articles" and those published in English. Articles dealing with cardiac surgery, interventional cardiology, and cardiovascular biology were excluded. Our search period was from January 1, 1988, through December 3, 2013. The 50 most frequently cited works were chosen, and a citation density was calculated for each, reflecting the average number of citations each received per year since publication. The articles were then sorted into a defined category, based on the clinical subject to which they pertained. The Citation Index Search resulted 80,379 articles, of which the top 50 were indexed and organized according to their citation density and area within the scope of clinical vascular surgery. The number of citations ranged from 218 to 3593. The median citation density was 50.2 (range, 11.3-201.3). This report is a representation of the most-cited original publications in the field of clinical vascular surgery during the last 25 years. This is an effort to highlight the seminal works that have shaped the discipline of vascular surgery as well as to provide a concise reference list for the surgical trainee in the process of his or her education. Copyright © 2014 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Access to medical care reported by Asians and Pacific Islanders in a West Coast physician group association.

PubMed

Snyder, R E; Cunningham, W; Nakazono, T T; Hays, R D

2000-06-01

This study examines access to medical care for Asians and Pacific Islanders in the United States, using a survey of patients receiving care provided by a physician group practice association concentrated on the West Coast. Asians and Pacific Islanders who had used their health plan in the past year had worse access to health care than whites, blacks, Hispanics, and Native American or other ethnicities. The odds that Asians reported that they had adequate access ranged from about one quarter to three quarters that of whites, depending on the measure. Cultural differences and associated communication problems may explain the access problems experienced by Asians. Interventions need to be developed to address the problems with access to services, and better translation services may play an important role in improving access to care for Asians. Future studies need to clarify why Asians were more vulnerable to the access problems examined than other ethnic groups that might experience similar barriers.

Planning for airport access: An analysis of the San Francisco Bay area. Three subsystem designs

NASA Technical Reports Server (NTRS)

1978-01-01

The outcomes of three analytical studies are presented. Areas of concentration presented include: (1) Zonal Airport Transit System designed to address the problem of airport access options, (2) the issues and problems of airport parking and circulation, and (3) the problems of effectively providing airport access information.

Principles of chronic venous access: recommendations based on the Roswell Park experience.

PubMed

Sabel, M S; Smith, J L

1997-11-01

At Roswell Park Cancer Institute, we have seen a dramatic increase in the need for long-term venous access. Chronic venous catheters are an indispensible part of the treatment provided to oncology patients. Cancer patients are often at higher risk for complications secondary to their underlying disease and treatments. These risks may be minimized by paying close attention to several important aspects of central line placement. These include matching individual patient needs with the access device most suited to those needs, a thorough preoperative assessment, and the safest and most appropriate operative approach for placement. Likewise, the prompt recognition and treatment of complications when they do occur is crucial to the care of these patients. In order to optimize the care of patients with long-term venous access devices, we have reviewed our experience of over 700 vascular access consultations and offer the following recommendations.

Case report: Unilateral conduction hearing loss due to central venous occlusion.

PubMed

Ribeiro, Phillip; Patel, Swetal; Qazi, Rizwan A

2016-05-07

Central venous stenosis is a well-known complication in patients with vascular access for hemodialysis. We report two cases involving patients on hemodialysis with arteriovenous fistulas who developed reversible unilateral conductive hearing loss secondary to critical stenosis of central veins draining the arteriovenous dialysis access. A proposed mechanism for the patients' reversible unilateral hearing loss is pterygoid venous plexus congestion leading to decreased Eustachian tube patency. Endovascular therapy was conducted to treat the stenosis and the hearing loss of both patients was returned to near normal after successful central venous angioplasty.

Parenteral Nutrition Basics for the Clinician Caring for the Adult Patient.

PubMed

Derenski, Karrie; Catlin, Jennifer; Allen, Livia

2016-10-01

Parenteral nutrition (PN) is a life-sustaining therapy providing nutrients to individuals with impaired intestinal tract function and enteral access challenges. It is one of the most complex prescriptions written routinely in the hospital and home care settings. This article is to aid the nutrition support clinician in the safe provision of PN, including selecting appropriate patients for PN, vascular access, development of a PN admixture, appropriate therapy monitoring, recognition of preparation options, and awareness of preparation and stability concerns. © 2016 American Society for Parenteral and Enteral Nutrition.

Ethnobotanical investigation of traditional medicinal plants commercialized in the markets of Mashhad, Iran

PubMed Central

Amiri, Mohammad Sadegh; Joharchi, Mohammad Reza

2013-01-01

Objective: An ethnobotanical survey on the medicinal plant species marketed in Mashhad city, northeastern Iran, was conducted in order to document traditional medicinal knowledge and application of medicinal plants. Materials and Methods: This study was undertaken between 2011 and 2012. The indigenous knowledge of traditional healers used for medicinal purposes were collected through questionnaire and personal interviews during field trips. Ethnobotanical data was arranged alphabetically by family name followed by botanical name, vernacular name, part used, folk use, and recipe. Correct identification was made with the help of the various Floras and different herbal literature at the Ferdowsi University of Mashhad Herbarium (FUMH). Results: The present investigation reported medicinal information for about 269 species, belonging to 87 vascular plant families and one fungus family. The most important family was Lamiaceae with 26 species, followed by Asteraceae with 23, Fabaceae with 20, and Apiaceae with 19. Herbal medicine uses reported by herbalists was classified into 132 different uses which show significant results to treat a wide spectrum of human ailments. Plants sold at the market were mostly used for digestive system disorders, respiratory problems, urological troubles, nervous system disorders, skin problems, and gynecological ailments. Conclusion: This survey showed that although people in study area have access to modern medical facilities, a lot of them still continue to depend on medicinal plants for the treatment of healthcare problems. The present paper represents significant ethnobotanical information on medical plants which provides baseline data for future pharmacological and phytochemical studies. PMID:25050282

Estimation of brachial artery volume flow by duplex ultrasound imaging predicts dialysis access maturation.

PubMed

Ko, Sae Hee; Bandyk, Dennis F; Hodgkiss-Harlow, Kelley D; Barleben, Andrew; Lane, John

2015-06-01

This study validated duplex ultrasound measurement of brachial artery volume flow (VF) as predictor of dialysis access flow maturation and successful hemodialysis. Duplex ultrasound was used to image upper extremity dialysis access anatomy and estimate access VF within 1 to 2 weeks of the procedure. Correlation of brachial artery VF with dialysis access conduit VF was performed using a standardized duplex testing protocol in 75 patients. The hemodynamic data were used to develop brachial artery flow velocity criteria (peak systolic velocity and end-diastolic velocity) predictive of three VF categories: low (<600 mL/min), acceptable (600-800 mL/min), or high (>800 mL/min). Brachial artery VF was then measured in 148 patients after a primary (n = 86) or revised (n = 62) upper extremity dialysis access procedure, and the VF category correlated with access maturation or need for revision before hemodialysis usage. Access maturation was conferred when brachial artery VF was >600 mL/min and conduit imaging indicated successful cannulation based on anatomic criteria of conduit diameter >5 mm and skin depth <6 mm. Measurements of VF from the brachial artery and access conduit demonstrated a high degree of correlation (R(2) = 0.805) for autogenous vein (n = 45; R(2) = 0.87) and bridge graft (n = 30; R(2) = 0.78) dialysis accesses. Access VF of >800 mL/min was predicted when the brachial artery lumen diameter was >4.5 mm, peak systolic velocity was >150 cm/s, and the diastolic-to-systolic velocity ratio was >0.4. Brachial artery velocity spectra indicating VF <800 mL/min was associated (P < .0001) with failure of access maturation. Revision was required in 15 of 21 (71%) accesses with a VF of <600 mL/min, 4 of 40 accesses (10%) with aVF of 600 to 800 mL/min, and 2 of 87 accesses (2.3%) with an initial VF of >800 mL/min. Duplex testing to estimate brachial artery VF and assess the conduit for ease of cannulation can be performed in 5 minutes during the initial postoperative vascular clinic evaluation. Estimation of brachial artery VF using the duplex ultrasound, termed the "Fast, 5-min Dialysis Duplex Scan," facilitates patient evaluation after new or revised upper extremity dialysis access procedures. Brachial artery VF correlates with access VF measurements and has the advantage of being easier to perform and applicable for forearm and also arm dialysis access. When brachial artery velocity spectra criteria confirm a VF >800 mL/min, flow maturation and successful hemodialysis are predicted if anatomic criteria for conduit cannulation are also present. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Challenges in translating vascular tissue engineering to the pediatric clinic.

PubMed

Duncan, Daniel R; Breuer, Christopher K

2011-10-14

The development of tissue-engineered vascular grafts for use in cardiovascular surgery holds great promise for improving outcomes in pediatric patients with complex congenital cardiac anomalies. Currently used synthetic grafts have a number of shortcomings in this setting but a tissue engineering approach has emerged in the past decade as a way to address these limitations. The first clinical trial of this technology showed that it is safe and effective but the primary mode of graft failure is stenosis. A variety of murine and large animal models have been developed to study and improve tissue engineering approaches with the hope of translating this technology into routine clinical use, but challenges remain. The purpose of this report is to address the clinical problem and review recent advances in vascular tissue engineering for pediatric applications. A deeper understanding of the mechanisms of neovessel formation and stenosis will enable rational design of improved tissue-engineered vascular grafts.

Angiogenesis Research to Improve Therapies for Vascular Leak Syndromes, Intra-abdominal Adhesions, and Arterial Injuries

DTIC Science & Technology

2008-04-01

small-cell lung cancer; TFP1, transferrin pseudogene 1; TGFβ, transforming growth factor-β; TNF, tumour- necrosis factor; uPA, urokinase-type plasminogen...Cell 79, 315–328 (1994). 23. Frater-Schroder, M., Risau, W., Hallmann, R., Gautschi, P. & Bohlen, P. Tumor necrosis factor type α, a potent inhibitor...relatively thin (skin) or avascular (cartilage) tissues, where post- implantation vascularization from the host is sufficient. To overcome the problem

Differential Responses of Vanilla Accessions to Root Rot and Colonization by Fusarium oxysporum f. sp. radicis-vanillae.

PubMed

Koyyappurath, Sayuj; Conéjéro, Geneviève; Dijoux, Jean Bernard; Lapeyre-Montès, Fabienne; Jade, Katia; Chiroleu, Frédéric; Gatineau, Frédéric; Verdeil, Jean Luc; Besse, Pascale; Grisoni, Michel

2015-01-01

Root and stem rot (RSR) disease caused by Fusarium oxysporum f. sp. radicis-vanillae (Forv) is the most damaging disease of vanilla (Vanilla planifolia and V. × tahitensis, Orchidaceae). Breeding programs aimed at developing resistant vanilla varieties are hampered by the scarcity of sources of resistance to RSR and insufficient knowledge about the histopathology of Forv. In this work we have (i) identified new genetic resources resistant to RSR including V. planifolia inbreds and vanilla relatives, (ii) thoroughly described the colonization pattern of Forv into selected vanilla accessions, confirming its necrotic non-vascular behavior in roots, and (iii) evidenced the key role played by hypodermis, and particularly lignin deposition onto hypodermal cell walls, for resistance to Forv in two highly resistant vanilla accessions. Two hundred and fifty-four vanilla accessions were evaluated in the field under natural conditions of infection and in controlled conditions using in vitro plants root-dip inoculated by the highly pathogenic isolate Fo072. For the 26 accessions evaluated in both conditions, a high correlation was observed between field evaluation and in vitro assay. The root infection process and plant response of one susceptible and two resistant accessions challenged with Fo072 were studied using wide field and multiphoton microscopy. In susceptible V. planifolia, hyphae penetrated directly into the rhizodermis in the hairy root region then invaded the cortex through the passage cells where it induced plasmolysis, but never reached the vascular region. In the case of the resistant accessions, the penetration was stopped at the hypodermal layer. Anatomical and histochemical observations coupled with spectral analysis of the hypodermis suggested the role of lignin deposition in the resistance to Forv. The thickness of lignin constitutively deposited onto outer cell walls of hypodermis was highly correlated with the level of resistance for 21 accessions tested. The accumulation of p-coumaric and sinapic acids, two phenolic precursors of lignin, was observed in the resistant plants inoculated with Fo072, but not in the susceptible one. Altogether, our analyses enlightened the mechanisms at work in RSR resistant genotypes and should enhance the development of novel breeding strategies aimed at improving the genetic control of RSR of vanilla.

The vascular and neurogenic factors associated with erectile dysfunction in patients after pelvic fractures

PubMed Central

Guan, Yong; Wendong, Sun; Zhao, Shengtian; Liu, Tongyan; Liu, Yuqiang; Zhang, Xiulin; Yuan, Mingzhen

2015-01-01

ABSTRACT Erectile dysfunction (ED) is a common complication of pelvic fractures. To identify the vascular and neurogenic factors associated with ED, 120 patients admitted with ED after traumatic pelvic fracture between January 2009 and June 2013 were enrolled in this study. All patients answered the International Index of Erectile Function (IIEF-5) questionnaire. Nocturnal penile tumescence (NPT) testing confirmed the occurrence of ED in 96 (80%) patients on whom penile duplex ultrasound and neurophysiological testing were further performed. Of these ED patients 29 (30%) were demonstrated only with vascular abnormality, 41 (42.7%) were detected only with neural abnormality, 26 (27.1%) revealed mixed abnormalities. Of the 55 patients (29+26) with vascular problems, 7 patients (12.7%) with abnormal arterial response to intracavernous injection of Bimix (15mg papaverine and 1mg phentolamine), 31 (56.4%) with corporal veno-occlusive dysfunction and 17 (30.9%) had both problems. Of the 67 (41+26) patients with abnormal neurophysiological outcomes, 51 (76.1%) with abnormal bulbocavernosus reflex (BCR), 20 (29.9%) with pathological pudendal nerve evoked potentials (PDEPs) and 25 (37.3%) with abnormal posterior tibial somatosensory nerve evoked potentials (PTSSEPs). Our observation indicated that neurogenic factors are important for the generation of ED in patients with pelvic fracture; venous impotence is more common than arteriogenic ED. PMID:26689522

Bioprinting for vascular and vascularized tissue biofabrication.

PubMed

Datta, Pallab; Ayan, Bugra; Ozbolat, Ibrahim T

2017-03-15

Bioprinting is a promising technology to fabricate design-specific tissue constructs due to its ability to create complex, heterocellular structures with anatomical precision. Bioprinting enables the deposition of various biologics including growth factors, cells, genes, neo-tissues and extra-cellular matrix-like hydrogels. Benefits of bioprinting have started to make a mark in the fields of tissue engineering, regenerative medicine and pharmaceutics. Specifically, in the field of tissue engineering, the creation of vascularized tissue constructs has remained a principal challenge till date. However, given the myriad advantages over other biofabrication methods, it becomes organic to expect that bioprinting can provide a viable solution for the vascularization problem, and facilitate the clinical translation of tissue engineered constructs. This article provides a comprehensive account of bioprinting of vascular and vascularized tissue constructs. The review is structured as introducing the scope of bioprinting in tissue engineering applications, key vascular anatomical features and then a thorough coverage of 3D bioprinting using extrusion-, droplet- and laser-based bioprinting for fabrication of vascular tissue constructs. The review then provides the reader with the use of bioprinting for obtaining thick vascularized tissues using sacrificial bioink materials. Current challenges are discussed, a comparative evaluation of different bioprinting modalities is presented and future prospects are provided to the reader. Biofabrication of living tissues and organs at the clinically-relevant volumes vitally depends on the integration of vascular network. Despite the great progress in traditional biofabrication approaches, building perfusable hierarchical vascular network is a major challenge. Bioprinting is an emerging technology to fabricate design-specific tissue constructs due to its ability to create complex, heterocellular structures with anatomical precision, which holds a great promise in fabrication of vascular or vascularized tissues for transplantation use. Although a great progress has recently been made on building perfusable tissues and branched vascular network, a comprehensive review on the state-of-the-art in vascular and vascularized tissue bioprinting has not reported so far. This contribution is thus significant because it discusses the use of three major bioprinting modalities in vascular tissue biofabrication for the first time in the literature and compares their strengths and limitations in details. Moreover, the use of scaffold-based and scaffold-free bioprinting is expounded within the domain of vascular tissue fabrication. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Acceleration of vascularized bone tissue-engineered constructs in a large animal model combining intrinsic and extrinsic vascularization.

PubMed

Weigand, Annika; Beier, Justus P; Hess, Andreas; Gerber, Thomas; Arkudas, Andreas; Horch, Raymund E; Boos, Anja M

2015-05-01

During the last decades, a range of excellent and promising strategies in Bone Tissue Engineering have been developed. However, the remaining major problem is the lack of vascularization. In this study, extrinsic and intrinsic vascularization strategies were combined for acceleration of vascularization. For optimal biomechanical stability of the defect site and simplifying future transition into clinical application, a primary stable and approved nanostructured bone substitute in clinically relevant size was used. An arteriovenous (AV) loop was microsurgically created in sheep and implanted, together with the bone substitute, in either perforated titanium chambers (intrinsic/extrinsic) for different time intervals of up to 18 weeks or isolated Teflon(®) chambers (intrinsic) for 18 weeks. Over time, magnetic resonance imaging and micro-computed tomography (CT) analyses illustrate the dense vascularization arising from the AV loop. The bone substitute was completely interspersed with newly formed tissue after 12 weeks of intrinsic/extrinsic vascularization and after 18 weeks of intrinsic/extrinsic and intrinsic vascularization. Successful matrix change from an inorganic to an organic scaffold could be demonstrated in vascularized areas with scanning electron microscopy and energy dispersive X-ray spectroscopy. Using the intrinsic vascularization method only, the degradation of the scaffold and osteoclastic activity was significantly lower after 18 weeks, compared with 12 and 18 weeks in the combined intrinsic-extrinsic model. Immunohistochemical staining revealed an increase in bone tissue formation over time, without a difference between intrinsic/extrinsic and intrinsic vascularization after 18 weeks. This study presents the combination of extrinsic and intrinsic vascularization strategies for the generation of an axially vascularized bone substitute in clinically relevant size using a large animal model. The additional extrinsic vascularization promotes tissue ingrowth and remodeling processes of the bone substitute. Extrinsic vessels contribute to faster vascularization and finally anastomose with intrinsic vasculature, allowing microvascular transplantation of the bone substitute after a shorter prevascularization time than using the intrinsic method only. It can be reasonably assumed that the usage of perforated chambers can significantly reduce the time until transplantation of bone constructs. Finally, this study paves the way for further preclinical testing for proof of the concept as a basis for early clinical applicability.

Barriers and facilitators to intraosseous access in adult resuscitations when peripheral intravenous access is not achievable.

PubMed

James Cheung, Warren; Rosenberg, Hans; Vaillancourt, Christian

2014-03-01

Studies suggest that intraosseous (IO) access is underutilized in adult resuscitations, despite recommendations from advanced trauma and cardiac life support guidelines. The objective was to determine factors associated with IO access use by physicians during adult resuscitations when intravenous (IV) access is not immediately achievable. This study was an online survey among physicians purposefully recruited from various clinical care areas at three teaching hospitals. Questions were generated from the qualitative results of 20 iterative interviews, verified for internal validity, and piloted. The interview guide was based on the constructs of the Theory of Planned Behavior (TPB), which elicits salient attitudes, social influences, and control beliefs that potentially influence intention to use IO access. Recruitment took place in September 2012 until reaching more than 100% of the required sample size (n = 200). Internal consistency was measured using Cronbach's alpha, and the effect of TPB constructs and specific beliefs were assessed with regression analyses. For the 205 respondents, the mean age was 35 years (range = 20 to 66 years), and 53.3% were male. Participants' departmental affiliations were 50.3% emergency medicine (EM), 16.9% internal medicine, 14.9% anesthesia, 10.8% general surgery, and 7.2% critical care. Residents comprised 60.7% of the sample, and 39.3% were attending physicians. Median intention to use IO access when IV is not immediately achievable was 4.67 (interquartile range [IQR] = 4 to 5) out of 5 (5 highest) and predicted by the following TPB constructs: attitudes (AdjCoefficients = 0.504; 95% confidence interval [CI] = 0.334 to 0.673), social influences (AdjCoefficients = 0.285; 95% CI = 0.172 to 0.398), and control beliefs (AdjCoefficients 0.217; 95% CI = 0.113 to 0.320). Physicians were more likely to use IO access if they believed that it provided rapid vascular access for delivering large volumes of fluids, could prevent delays in care, and was associated with a low complication rate. Conversely, the perception that nurses are not familiar or supportive of IO access and a lack of physician confidence regarding the appropriate indications for IO access were barriers to use. These data are an important step in the knowledge-to-action process, as they identify specific factors associated with physician use of IO access. Interventions addressing these actionable facilitators and barriers are likely to have a positive effect on increasing the appropriate physician use of this potentially life-saving technique in adult patients requiring emergent vascular access. © 2014 by the Society for Academic Emergency Medicine.

Telomerase Reverse Transcriptase Deficiency Prevents Neointima Formation Through Chromatin Silencing of E2F1 Target Genes.

PubMed

Endorf, Elizabeth B; Qing, Hua; Aono, Jun; Terami, Naoto; Doyon, Geneviève; Hyzny, Eric; Jones, Karrie L; Findeisen, Hannes M; Bruemmer, Dennis

2017-02-01

Aberrant proliferation of smooth muscle cells (SMC) in response to injury induces pathological vascular remodeling during atherosclerosis and neointima formation. Telomerase is rate limiting for tissue renewal and cell replication; however, the physiological role of telomerase in vascular diseases remains to be determined. The goal of the present study was to determine whether telomerase reverse transcriptase (TERT) affects proliferative vascular remodeling and to define the molecular mechanism by which TERT supports SMC proliferation. We first demonstrate high levels of TERT expression in replicating SMC of atherosclerotic and neointimal lesions. Using a model of guidewire-induced arterial injury, we demonstrate decreased neointima formation in TERT-deficient mice. Studies in SMC isolated from TERT-deficient and TERT overexpressing mice with normal telomere length established that TERT is necessary and sufficient for cell proliferation. TERT deficiency did not induce a senescent phenotype but resulted in G1 arrest albeit hyperphosphorylation of the retinoblastoma protein. This proliferative arrest was associated with stable silencing of the E2F1-dependent S-phase gene expression program and not reversed by ectopic overexpression of E2F1. Finally, chromatin immunoprecipitation and accessibility assays revealed that TERT is recruited to E2F1 target sites and promotes chromatin accessibility for E2F1 by facilitating the acquisition of permissive histone modifications. These data indicate a previously unrecognized role for TERT in neointima formation through epigenetic regulation of proliferative gene expression in SMC. © 2016 American Heart Association, Inc.

Vascular Accesses for Haemodialysis in the Upper Arm Cause Greater Reduction in the Carotid-Brachial Stiffness than Those in the Forearm: Study of Gender Differences

PubMed Central

Bia, Daniel; Cabrera-Fischer, Edmundo I.; Zócalo, Yanina; Galli, Cintia; Graf, Sebastián; Valtuille, Rodolfo; Pérez-Cámpos, Héctor; Saldías, María; Álvarez, Inés; Armentano, Ricardo L.

2012-01-01

Purpose. To evaluate in chronically haemodialysed patients (CHPs), if: (1) the vascular access (VA) position (upper arm or forearm) is associated with differential changes in upper limb arterial stiffness; (2) differences in arterial stiffness exist between genders associated with the VA; (3) the vascular substitute (VS) of choice, in biomechanical terms, depends on the previous VA location and CHP gender. Methods. 38 CHPs (18 males; VA in upper arm: 18) were studied. Left and right carotid-brachial pulse wave velocity (PWVc-b) was measured. In in vitro studies, PWV was obtained in ePTFE prostheses and in several arterial and venous homografts obtained from donors. The biomechanical mismatch (BM) between CHP native vessel (NV) and VS was calculated. Results/Conclusions. PWVc-b in upper limbs with VA was lower than in the intact contralateral limbs (P < 0.05), and differences were higher (P < 0.05) when the VA was performed in the upper arm. Differences between PWVc-b in upper limbs with VA (in the upper arm) with respect to intact upper limbs were higher (P < 0.05) in males. Independently of the region in which the VA was performed, the homograft that ensured the minimal BM was the brachial artery. The BM was highly dependent on gender and the location in the upper limb in which the VA was performed. PMID:22567282

Resuscitation from Hypovolemia in Swine with Intraosseous Infusion of a Saturated Salt-Dextran Solution (SSD)

DTIC Science & Technology

1992-10-01

marrow and the proximal tibia is often used for emergency vascular access (3-5). In adults, however, avascular yellow marrow replaces the red marrow of...for histological evaluation of acute lesions, presence or absence of thrombi, fat or bone emboli, necrosis or hemorrhage to the lung, and decreased

Clinical Record of Emergency Vascular Access Using Adult Intraosseous (IO) Devices

DTIC Science & Technology

2004-09-01

which were disposable and similar in design to the reusable trocared needles of Paper and Bailey needles ( Papper , 1942; Bailey 1944; Glaeser, 1993...shock in a swine model. J Trauma 1993 Mar;34(3):422- 8. Papper , EM. The bone marrow route for injecting fluids and drugs into the general circulation

Angiographic follow-up of infants and children undergoing percutaneous carotid artery interventions.

PubMed

Ligon, R Allen; Kim, Dennis W; Vincent, Robert N; Bauser-Heaton, Holly D; Ooi, Yinn K; Petit, Christopher J

2018-01-23

The purpose of this study was to review the outcomes following the percutaneous carotid arterial (PCA) approach in infants and children with congenital heart disease. PCA access is becoming more commonly adopted following reports demonstrating it is a safe alternative to surgical carotid cutdown and even the femoral arterial route. However, follow-up outcomes after PCA remain unreported. We reviewed all cases with PCA access and follow-up catheterizations which included carotid artery (CA) angiography between May 2012 until December 2016. We examined for evidence of CA stenosis at follow-up angiography and assessed any other CA complications associated with vascular access. There were 61 PCA catheterizations performed in 55 unique patients. Follow-up CA imaging with angiography was available in 43 patients (78%, 43/55). There was no vessel stenosis nor lumen irregularity in 28 (65%) patients. In 15 cases (35%), there was a mild degree of irregularity or narrowing by angiography (median 4.1%, range 2.3%-12.5%). Nine patients underwent repeat PCA catheterizations. Seven of these had no visible vascular stenosis on follow-up angiographic imaging, including a patient who was accessed three separate times from the CA. No statistically significant risk factors for developing mild CA stenosis were identified. PCA access for pediatric interventional catheterization appears to be safe with a very low rate of mild stenosis, and very few complications. Follow-up outcomes in our series are excellent, with a CA patency rate of 100%, even after multiple procedures. Mild CA stenosis was not associated with patient size or sheath introducer caliber. While the acute results from percutaneous CA catheterization have proven safe in recent literature, longer-term outcomes remain unreported. At our institution, the outcomes following percutaneous carotid access are associated with an excellent patency rate of 100%, even after multiple procedures on the same vessel. A low incidence of mild vessel stenosis can be appreciated on follow-up angiography. © 2018 Wiley Periodicals, Inc.

Local Drug Delivery to Prevent Restenosis

PubMed Central

Seedial, Stephen M.; Ghosh, Soumojit; Saunders, R. Scott; Suwanabol, Pasithorn A.; Shi, Xudong; Liu, Bo; Kent, K. Craig

2013-01-01

Introduction Despite significant advances in vascular biology, bioengineering and pharmacology, restenosis remains a limitation to the overall efficacy of vascular reconstructions, both percutaneous and open. Although the pathophysiology of intimal hyperplasia is complex, a number of drugs and/or molecular tools have been identified that can prevent restenosis. Moreover, the focal nature of this process lends itself to treatment with local drug administration. In this article we provide a broad overview of current and future techniques for local drug delivery that have been developed to prevent restenosis following vascular intervention. Methods A systematic electronic literature search using PubMed was performed for all accessible published articles through September 2012. In an effort to remain current, additional searches were performed for abstracts presented at relevant societal meetings, filed patents, clinical trials and funded NIH awards. Results The efficacy of local drug delivery has been demonstrated in the coronary circulation with the current clinical use of drug-eluting stents (DES). Until recently, however, DES were not found to be efficacious in the peripheral circulation. Further pursuit of intraluminal devices has led to the development of balloon-based technologies with a recent surge in trials involving drug-eluting balloons. Early data appears encouraging, particularly for treatment of lesions in the superficial femoral artery, with several devices having recently received the CE mark in Europe. Investigators have also explored periadventitial application of biomaterials containing anti-restenotic drugs, an approach that could be particularly useful for surgical bypass or endarterectomy. In the past systemic drug delivery has been unsuccessful, however, there has been recent exploration of intravenous delivery of drugs designed specifically to target injured or reconstructed arteries. Our review revealed a multitude of additional interesting strategies including more than 65 new patents issued over the past two years for approaches to local drug delivery focused on preventing restenosis. Conclusion Restenosis following intraluminal or open vascular reconstruction remains an important clinical problem. Success in the coronary circulation has not translated into solutions for the peripheral arteries. However, our review of the literature reveals a number of promising approaches including drug-eluting balloons, periadventitial drug delivery as well as targeted systemic therapies. These innovations as well as others suggest that the future is bright and a solution for preventing restenosis in peripheral vessels will soon be at hand. PMID:23601595

Flora-On: Occurrence data of the vascular flora of mainland Portugal

PubMed Central

Pereira, Ana Júlia; Francisco, Ana; Porto, Miguel

2016-01-01

Abstract The Flora-On dataset currently includes 253,310 occurrence records for the class Embryopsidae (vascular plants), comprising data collated via the platform http://flora-on.pt/ relating to observation records of vascular plants across mainland Portugal. Observations are uploaded directly to the database primarily by experienced botanists and naturalists, typically on a weekly basis, and consist of geo-referenced data points for species (or infraspecific taxa) along with their date of observation and phenological state. The Flora-On project aims to compile and make publicly accessible chorological, ecological, morphological and photographic information for the entire vascular flora of Portugal. The project’s website offers powerful query and visualization capabilities, of which we highlight the probabilistic bioclimatic and phenological queries which operate based on the empirical density distributions of species in those variables. Flora-On was created and continues to be maintained by volunteers who are Associate members of Sociedade Portuguesa de Botânica (Botanical Society of Portugal). Given its focus on research-grade and current data, the Flora-On project represents a significant contribution to the knowledge of the present distribution and status of the Portuguese flora. PMID:27698587

Adventitial delivery of lentivirus-shRNA-ADAMTS-1 reduces venous stenosis formation in arteriovenous fistula.

PubMed

Nieves Torres, Evelyn C; Yang, Binxia; Roy, Bhaskar; Janardhanan, Rajiv; Brahmbhatt, Akshaar; Leof, Ed; Mukhopadhyay, Debabrata; Misra, Sanjay

2014-01-01

Hemodialysis vascular access can develop venous neointimal hyperplasia (VNH) causing stenosis. Recent clinical and experimental data has demonstrated that there is increased expression of a disintegrin and metalloproteinase thrombospondin motifs-1 (ADAMTS-1) at site of VNH. The experiments outlined in the present paper were designed to test the hypothesis that targeting of the adventitia of the outflow vein of murine arteriovenous fistula (AVF) using a small hairpin RNA that inhibits ADAMTS-1 expression (LV-shRNA-ADAMTS-1) at the time of fistula creation will decrease VNH. At early time points, ADAMTS-1 expression was significantly decreased associated with a reduction in vascular endothelial growth factor-A (VEGF-A) and matrix metalloproteinase-9 (MMP-9) (LV-shRNA-ADAMTS-1 transduced vessels vs. controls). These changes in gene and protein expression resulted in favorable vascular remodeling with a significant increase in mean lumen vessel area, decrease in media/adventitia area, with a significant increase in TUNEL staining accompanied with a decrease in cellular proliferation accompanied with a reduction in CD68 staining. Collectively, these results demonstrate that ADAMTS-1 transduced vessels of the outflow vein of AVF have positive vascular remodeling.

Adventitial Delivery of Lentivirus-shRNA-ADAMTS-1 Reduces Venous Stenosis Formation in Arteriovenous Fistula

PubMed Central

Janardhanan, Rajiv; Brahmbhatt, Akshaar; Leof, Ed; Mukhopadhyay, Debabrata; Misra, Sanjay

2014-01-01

Hemodialysis vascular access can develop venous neointimal hyperplasia (VNH) causing stenosis. Recent clinical and experimental data has demonstrated that there is increased expression of a disintegrin and metalloproteinase thrombospondin motifs-1 (ADAMTS-1) at site of VNH. The experiments outlined in the present paper were designed to test the hypothesis that targeting of the adventitia of the outflow vein of murine arteriovenous fistula (AVF) using a small hairpin RNA that inhibits ADAMTS-1 expression (LV-shRNA-ADAMTS-1) at the time of fistula creation will decrease VNH. At early time points, ADAMTS-1 expression was significantly decreased associated with a reduction in vascular endothelial growth factor-A (VEGF-A) and matrix metalloproteinase-9 (MMP-9) (LV-shRNA-ADAMTS-1 transduced vessels vs. controls). These changes in gene and protein expression resulted in favorable vascular remodeling with a significant increase in mean lumen vessel area, decrease in media/adventitia area, with a significant increase in TUNEL staining accompanied with a decrease in cellular proliferation accompanied with a reduction in CD68 staining. Collectively, these results demonstrate that ADAMTS-1 transduced vessels of the outflow vein of AVF have positive vascular remodeling. PMID:24732590

Cross-over endovascular retrieval of a lost guide wire from the subclavian vein.

PubMed

Struck, M F; Kaden, I; Heiser, A; Steen, M

2008-01-01

The lost guidewire in central venous catheterization is a commonly described complication. The percutaneous endovascular retrieval method is safe and has a very low complication rate. Guidewires extending to the inferior cava vein are usually retrieved via the femoral vein. Under special circumstances, femoral venous access may be impossible and alternative vascular approaches are required. We report a case in which we used an alternative vascular approach, from the subclavian site contralateral to the insertion, in a patient with extensive inguinal burn injuries. Cross-over subclavian retrieval can be an alternative approach for retrieval of a lost guidewire, but it involves an increased risk of puncture-related complications such as pneumothorax.

Frequent accesses to totally implanted vascular ports in pediatric oncology patients are associated with higher infection rates.

PubMed

Gapany, Christophe; Tercier, Stéphane; Diezi, Manuel; Clement, Chantal; Lemay, Katy; Joseph, Jean-Marc

2011-01-01

Totally implanted vascular (TIVA) ports are used in children for repeated blood samples or intravenous treatments. We have recently published a prospective evaluation of surgical incidents and early complications associated with these devices. This work is the final part of the same study, assessing late complications over a follow-up of 2 yrs. From January 2006 to January 2008, children older than 1 yr of age with a diagnosis of solid or blood cell malignancy were included. Insertion technique and care of the device were standardized. Every manipulation was prospectively recorded by specialized nurses. Obstruction was documented clinically. When bacteremia was suspected, routine central and peripheral blood cultures were drawn. Forty-five consecutive patients were enrolled in the study. Mean age at the time of the procedure was 8.5 yrs. There was no catheter-related infection within the first 4 weeks post-surgery. No device had to be removed because of infection or obstruction during follow-up. Frequent accesses to the port (=3 per day over a 10-day period) were associated with an 8-fold risk of infection. Insertion and use of TIVA devices were frequently associated with complications. No device had to be removed because of infection or obstruction over the follow-up period, although no prophylactic antibiotic agent was used. Restrictive use of antibiotics may prevent opportunistic infection. Frequent access to the device was significantly associated with line infection (odds ratio=8.43). No risk factor was identified for obstruction which occurred at a rate of 5.3 per 10,000 accesses.

What do parents perceive are the barriers and facilitators to accessing psychological treatment for mental health problems in children and adolescents? A systematic review of qualitative and quantitative studies.

PubMed

Reardon, Tessa; Harvey, Kate; Baranowska, Magdalena; O'Brien, Doireann; Smith, Lydia; Creswell, Cathy

2017-06-01

A minority of children and adolescents with mental health problems access treatment. The reasons for poor rates of treatment access are not well understood. As parents are a key gatekeeper to treatment access, it is important to establish parents' views of barriers/facilitators to accessing treatment. The aims of this study are to synthesise findings from qualitative and quantitative studies that report parents' perceptions of barriers/facilitators to accessing treatment for mental health problems in children/adolescents. A systematic review and narrative synthesis were conducted. Forty-four studies were included in the review and were assessed in detail. Parental perceived barriers/facilitators relating to (1) systemic/structural issues; (2) views and attitudes towards services and treatment; (3) knowledge and understanding of mental health problems and the help-seeking process; and (4) family circumstances were identified. Findings highlight avenues for improving access to child mental health services, including increased provision that is free to service users and flexible to their needs, with opportunities to develop trusting, supportive relationships with professionals. Furthermore, interventions are required to improve parents' identification of mental health problems, reduce stigma for parents, and increase awareness of how to access services.

Advanced Stent Graft Treatment of Venous Stenosis Affecting Hemodialysis Vascular Access: Case Illustrations

PubMed Central

Patel, Darshan; Ray, Charles E.; Lokken, R. Peter; Bui, James T.; Lipnik, Andrew J.; Gaba, Ron C.

2016-01-01

Surgically placed dialysis access is an important component of dialysis replacement therapy. The vast majority of patients undergoing dialysis will have surgically placed accesses at some point in the course of their disease, and for many patients these accesses may represent their definitive renal replacement option. Most, if not all, arteriovenous fistulae and grafts will require interventions at some point in time. Percutaneous angioplasty is the typical first treatment performed for venous stenoses, with stents and stent grafts being reserved for patients in whom angioplasty and surgical options are exhausted. In some salvage situations, stent graft placement may be the only or best option for patients. This article describes, using case illustrations, placement of stent grafts in such patients; a focus will also be made on the techniques utilized in such salvage situations. PMID:27011426

How good is the management of vascular risk after stroke, transient ischaemic attack or carotid endarterectomy?

PubMed

Johnson, Paul; Rosewell, Mary; James, Martin A

2007-01-01

Patients remain at high risk of vascular events after stroke, transient ischaemic attack or carotid endarterectomy. We studied how well this risk is addressed by the effective treatment of modifiable risk factors. A total of 198 consecutive attenders at a rapid access stroke clinic and 98 consecutive patients undergoing carotid endarterectomy were studied. Treatment of hypertension and hyperlipidaemia, smoking status and the use of antithrombotic therapy were assessed at baseline and 6 months later. The findings were compared with targets from the UK National Clinical Guidelines for Stroke. Baseline and follow-up data were available on 284 patients. The rates of control of vascular risk factors improved only slightly during follow-up. Blood pressure was below target levels in only 69 (24%) at baseline and 79 (28%) at 6 months, and serum cholesterol was below target levels in only 55 (19%) at baseline and 63 (22%) at 6 months. At baseline, 55 (19%) were smokers, of whom 12 (22%) had quit at 6 months. Anticoagulant therapy was prescribed in 19 of 37 patients (51%) in atrial fibrillation at 6 months. Antiplatelet therapy was prescribed in 90% of patients in sinus rhythm. Despite the identification of vascular risk factors at the time of clinic or surgery, 6 months later these risk factors remain poorly addressed. More effective methods of managing vascular risk in these patients are needed.

What students learn when studying physics practice exam problems

NASA Astrophysics Data System (ADS)

Fakcharoenphol, Witat; Potter, Eric; Stelzer, Timothy

2011-06-01

We developed a web-based tool to provide students with access to old exam problems and solutions. By controlling the order in which students saw the problems, as well as their access to solutions, we obtained data about student learning by studying old exam problems. Our data suggest that in general students learn from doing old exam problems, and that having access to the problem solutions increases their learning. However, the data also suggest the depth of learning may be relatively shallow. In addition, the data show that doing old exam problems provides important formative assessment about the student’s overall preparedness for the exam and their particular areas of strength and weakness.

Global Genome Biodiversity Network: saving a blueprint of the Tree of Life – a botanical perspective

PubMed Central

Seberg, O.; Droege, G.; Barker, K.; Coddington, J. A.; Funk, V.; Gostel, M.; Petersen, G.; Smith, P. P.

2016-01-01

Background Genomic research depends upon access to DNA or tissue collected and preserved according to high-quality standards. At present, the collections in most natural history museums do not sufficiently address these standards, making them often hard or impossible to use for whole-genome sequencing or transcriptomics. In response to these challenges, natural history museums, herbaria, botanical gardens and other stakeholders have started to build high-quality biodiversity biobanks. Unfortunately, information about these collections remains fragmented, scattered and largely inaccessible. Without a central registry or even an overview of relevant institutions, it is difficult and time-consuming to locate the needed samples. Scope The Global Genome Biodiversity Network (GGBN) was created to fill this vacuum by establishing a one-stop access point for locating samples meeting quality standards for genome-scale applications, while complying with national and international legislations and conventions. Increased accessibility to genomic samples will further genomic research and development, conserve genetic resources, help train the next generation of genome researchers and raise the visibility of biodiversity collections. Additionally, the availability of a data-sharing platform will facilitate identification of gaps in the collections, thereby empowering targeted sampling efforts, increasing the breadth and depth of preservation of genetic diversity. The GGBN is rapidly growing and currently has 41 members. The GGBN covers all branches of the Tree of Life, except humans, but here the focus is on a pilot project with emphasis on ‘harvesting’ the Tree of Life for vascular plant taxa to enable genome-level studies. Conclusion While current efforts are centred on getting the existing samples of all GGBN members online, a pilot project, GGI-Gardens, has been launched as proof of concept. Over the next 6 years GGI-Gardens aims to add to the GGBN high-quality genetic material from at least one species from each of the approx. 460 vascular plant families and one species from half of the approx. 15 000 vascular plant genera. PMID:27328683

[Interventional radiology: current problems and new directions].

PubMed

Santos Martín, E; Crespo Vallejo, E

2014-01-01

In recent years, vascular and interventional radiology has become one of the fastest growing diagnostic and therapeutic specialties. This growth has been based on a fundamental concept: performing minimally invasive procedures under imaging guidance. This attractive combination has led to the interest of professionals from other clinical specialties outside radiology in performing this type of intervention. The future of vascular and interventional radiology, although uncertain, must be linked to clinical practice and multidisciplinary teamwork. Copyright © 2011 SERAM. Published by Elsevier Espana. All rights reserved.

Pulsed dye laser application in ablation of vascular ectasias of the larynx: a preliminary animal study

NASA Astrophysics Data System (ADS)

Woo, Peak; Wang, Zhi; Perrault, Donald F., Jr.; McMillan, Kathleen; Pankratov, Michail M.

1995-05-01

Vascular ectasias (dilatation) and vascular lesions of the larynx are difficult to treat with exciting modalities. Varix (enlarged vessel) of the vocal folds, vocal fold hemorrhage, vascular polyp, hemangioma, intubation or contact granuloma are common problems which disturb voice. Current applications of CO2 laser and cautery often damage the delicate vocal fold cover. The 585 nm dermatologic pulsed dye laser may be an ideal substitute. Two adult canines were examined under anesthesia via microlaryngoscopy technique. Pulsed dye laser (SPTL-1a, Candela Laser Corp., Wayland, MA) energy was delivered via the micromanipulator with the 3.1-mm spot size in single pulses of 6, 8, and 10 Joules/cm2 and applied to the vessels of the vocal folds, epiglottis, and arytenoid cartilage. Endoscopic examination was carried out immediately after the treatment and at 4 weeks postoperatively. The animals were sacrificed at 3 weeks, larynges excised, and whole organ laryngeal section were prepared for histology. Pulsed dye laser thrombosed vessels of the vocal fold using 6 or 8 Joules/cm2. Vascular break and leakage occurred at 10 Joules/cm2. Follow up examination showed excellent vessel obliteration or thrombosis without scarring or injury to the overlying tissues. Histologic examination shows vascular thrombosis without inflammation and fibrosis in the vocal fold cover. Pulsed dye laser may have promise in treatment of vascular lesions of the larynx and upper airway.

Peripheral intravenous and central catheter algorithm: a proactive quality initiative.

PubMed

Wilder, Kerry A; Kuehn, Susan C; Moore, James E

2014-12-01

Peripheral intravenous (PIV) infiltrations causing tissue damage is a global issue surrounded by situations that make vascular access decisions difficult. The purpose of this quality improvement project was to develop an algorithm and assess its effectiveness in reducing PIV infiltrations in neonates. The targeted subjects were all infants in our neonatal intensive care unit (NICU) with a PIV catheter. We completed a retrospective chart review of the electronic medical record to collect 4th quarter 2012 baseline data. Following adoption of the algorithm, we also performed a daily manual count of all PIV catheters in the 1st and 2nd quarters 2013. Daily PIV days were defined as follows: 1 patient with a PIV catheter equals 1 PIV day. An infant with 2 PIV catheters in place was counted as 2 PIV days. Our rate of infiltration or tissue damage was determined by counting the number of events and dividing by the number of PIV days. The rate of infiltration or tissue damage was reported as the number of events per 100 PIV days. The number of infiltrations and PIV catheters was collected from the electronic medical record and also verified manually by daily assessment after adoption of the algorithm. To reduce the rate of PIV infiltrations leading to grade 4 infiltration and tissue damage by at least 30% in the NICU population. Incidence of PIV infiltrations/100 catheter days. The baseline rate for total infiltrations increased slightly from 5.4 to 5.68/100 PIV days (P = .397) for the NICU. We attributed this increase to heightened awareness and better reporting. Grade 4 infiltrations decreased from 2.8 to 0.83/100 PIV catheter days (P = .00021) after the algorithm was implemented. Tissue damage also decreased from 0.68 to 0.3/100 PIV days (P = .11). Statistical analysis used the Fisher exact test and reported as statistically significant at P < .05. Our findings suggest that utilization of our standardized decision pathway was instrumental in providing guidance for problem solving related to vascular access decisions. We feel this contributed to the overall reduction in grade 4 intravenous infiltration and tissue damage rates. Grade 4 infiltration reductions were highly statistically significant (P = .00021).

Endothelial cell motility, coordination and pattern formation during vasculogenesis.

PubMed

Czirok, Andras

2013-01-01

How vascular networks assemble is a fundamental problem of developmental biology that also has medical importance. To explain the organizational principles behind vascular patterning, we must understand how can tissue level structures be controlled through cell behavior patterns like motility and adhesion that, in turn, are determined by biochemical signal transduction processes? We discuss the various ideas that have been proposed as mechanisms for vascular network assembly: cell motility guided by extracellular matrix alignment (contact guidance), chemotaxis guided by paracrine and autocrine morphogens, and multicellular sprouting guided by cell-cell contacts. All of these processes yield emergent patterns, thus endothelial cells can form an interconnected structure autonomously, without guidance from an external pre-pattern. © 2013 Wiley Periodicals, Inc.

The role of the vascular surgeon in anterior lumbar spine surgery.

PubMed

Asha, Mohammed Jamil; Choksey, Munchi S; Shad, Amjad; Roberts, Peter; Imray, Chris

2012-08-01

Advances in spinal fusion techniques have led to an increase in the need for safe access to the lumbar spine anteriorly. The aim of this study is to examine the procedure-related complications of anterior lumbar inter-body fusion (ALIF) or anterior lumbar disc replacement (ALDR) when performed jointly by a vascular-surgeon and a neurosurgeon in a single centre. A retrospective cohort analysis was conducted for all patients who underwent ALIF or ALDR between 2004 and 2010. Operative notes were examined to identify any procedure-specific complications. In-hospital postoperative complications were recorded. Outpatients' records were reviewed to record any late-onset postoperative complications. A total of 121 patients (68 female and 53 males) were included. Mean age was 44 years (range of 25-76). Eighty patients (66%) had ALIF while 24 patients (20%) underwent ALDR. The remaining 17 patients (14%) had combined procedure for multilevel disease. In all patients, a transperitoneal approach was performed by vascular surgeon. The main indication (88%) for performing surgery was degenerative lumbar disc disease. No visceral or 'major vascular' complications were reported in any patients. Only three patients had 'minor vascular' injuries. The only significant postoperative complication was self-limiting paralytic ileus affecting 18 patients (14.8%). Hospital stay ranged from 4 to 9 days (median of 5 days). The anterior lumbar approach is not generally favoured by many neurosurgeons, despite its many advantages, due to the significant risk of vascular injuries as reported in the literature. This risk is especially acknowledged by the emerging generation of neurosurgeons with very little general surgical exposure during the training years. Adopting a combined vascular and neurosurgical approach has been reported to reduce the risk of vascular injury in anterior lumbar surgery acceptably low. This team approach provides an excellent opportunity to preserve some key 'general' surgical skills for neurosurgeons and ensure safe outcome for the patients.

The glycocalyx and its significance in human medicine.

PubMed

Tarbell, J M; Cancel, L M

2016-07-01

Cells are covered by a surface layer of glycans that is referred to as the 'glycocalyx'. In this review, we focus on the role of the glycocalyx in vascular diseases (atherosclerosis, stroke, hypertension, kidney disease and sepsis) and cancer. The glycocalyx and its principal glycosaminoglycans [heparan sulphate (HS) and hyaluronic acid (HA)] and core proteins (syndecans and glypicans) are degraded in vascular diseases, leading to a breakdown of the vascular permeability barrier, enhanced access of leucocytes to the arterial intima that propagate inflammation and alteration of endothelial mechanotransduction mechanisms that protect against disease. By contrast, the glycocalyx on cancer cells is generally robust, promoting integrin clustering and growth factor signalling, and mechanotransduction of interstitial flow shear stress that is elevated in tumours to upregulate matrix metalloproteinase release which enhances cell motility and metastasis. HS and HA are consistently elevated on cancer cells and are associated with tumour growth and metastasis. Later, we will review the agents that might be used to enhance or protect the glycocalyx to combat vascular disease, as well as a different set of compounds that can degrade the cancer cell glycocalyx to suppress cell growth and metastasis. It is clear that what is beneficial for either vascular disease or cancer will not be so for the other. The overarching conclusions are that (i) the importance of the glycocalyx in human medicine is only beginning to be recognized, and (ii) more detailed studies of glycocalyx involvement in vascular diseases and cancer will lead to novel treatment modalities. © 2016 The Association for the Publication of the Journal of Internal Medicine.

XXIst century magnetotherapy.

PubMed

Markov, M

2015-09-01

This paper discusses the state of the art therapeutic application of magnetic and electromagnetic fields (EMF) in treatment of various medical problems - from pain relief to musculoskeletal trauma, to vascular and endocrine disorders. The paper describes problems related to physical parameters of used fields, biophysical dosimetry, clinical protocols, and safety of the device operators. Clinical benefits and mechanisms of action are also discussed.

Non-operative management of hepatic trauma and the interventional radiology: an update review.

PubMed

Pereira, Bruno Monteiro Tavares

2013-10-01

The growing trend to manage hepatic injuries nonoperatively has been increasing demand for advanced endovascular interventions. This brings up the necessity for general and trauma surgeons to update their knowledge in such matter. Effective treatment mandates a multispecialty team effort that is usually led by the trauma surgeon and includes vascular surgery, orthopedics, and, increasingly, interventional radiology. The focus on hemorrhage control and the angiographer's unique access to vascular structures gives interventional radiology (IR) an important and increasingly recognized role in the treatment of patients with hemodynamic instability. Our aim is to review the basic concepts of IR primarily in hepatic trauma and secondarily in some other special situations. A liver vascular anatomy review is also needed for better understanding the roles of IR. As a final point we propose a guideline for the operative/nonoperative management of traumatic hepatic injuries. The benefit of multidisciplinary approach (TAE) appears to be a powerful weapon in the medical arsenal against the high mortality of injured trauma liver patients.

[Care plan for patients in prone decubitus. An experience from practice].

PubMed

Oliva Torras, E; Subirana Casacuberta, M; Sebastià, M P; Jover Sancho, C; Solà Solé, N

1995-01-01

Offering a specific integral attention to patients with SDRA in prone decubitus positions makes us establish a performance plan with the aim to know the problems derived from the change in position, the time staying in prone decubitus and to standardize a care plan. We review the clinic records of the patients admitted in our unit from March '93 to March '95 who were positioned in prone decubitus. Taking as a base the nursing care model of V. Henderson and the taxonomy of NANDA, we analyse the needs which have been altered, and determine the nursing diagnosis, complications and most frequent interdependent problems establishing the aim to accomplish, planning the performance and rationalization. Five patients were positioned in prone decubitus before planning the performance and four more afterwards. All the patients tolerated SNG diet keeping a correct bowel transit. One patient showed an ulcera at frontal level. There were neither comeal ulceras nor alterations in the oral mucossa. The vascular accesses remained permeable. DP caused facial and periorbital edema in all the patients. We did not observe any increase in the amount of bronchial secretions. The eight patients who tolerated the change in position stayed in prone decubitus for an average of 77 hours, with a range of 10 to 216 hours. Four patients were discharged from the hospital, two of whom showed movility alterations, independently of the time staying in prone decubitus. We state explicitly the nursing care, determine five nursing diagnosis, one problem and seven interdependent complications. Establishing the nursing care from the experience and review of the records has allowed us to be more specific and objective. Standardizing the specific care plans makes the nursing care easier when dealing with real problems as well as with the care of complications derived from this situation.

Safety of contemporary percutaneous peripheral arterial interventions in the elderly insights from the BMC2 PVI (Blue Cross Blue Shield of Michigan Cardiovascular Consortium Peripheral Vascular Intervention) registry.

PubMed

Plaisance, Benjamin R; Munir, Khan; Share, David A; Mansour, M Ashraf; Fox, James M; Bove, Paul G; Riba, Arthur L; Chetcuti, Stanley J; Gurm, Hitinder S; Grossman, P Michael

2011-06-01

This study sought to evaluate the effect of age on procedure type, periprocedural management, and in-hospital outcomes of patients undergoing lower-extremity (LE) peripheral vascular intervention (PVI). Surgical therapy of peripheral arterial disease is associated with significant morbidity and mortality in the elderly. There are limited data related to the influence of advanced age on the outcome of patients undergoing percutaneous LE PVI. Clinical presentation, comorbidities, and in-hospital outcomes of patients undergoing LE PVI in a multicenter, multidisciplinary registry were compared between 3 age groups: < 70 years, between 70 and 80 years, and ≥ 80 years (elderly group). In our cohort, 7,769 patients underwent LE PVI. The elderly patients were more likely to be female and to have a greater burden of comorbidities. Procedural success was lower in the elderly group (74.2% for age ≥ 80 years vs. 78% for age 70 to < 80 years and 81.4% in patients age < 70 years, respectively; p < 0.0001). Unadjusted rates of procedure-related vascular access complications, post-procedure transfusion, contrast-induced nephropathy, amputation, and major adverse cardiac events were higher in elderly patients. After adjustment for baseline covariates, the elderly patients were more likely to experience vascular access complications; however, advanced age was not found to be associated with major adverse cardiac events, transfusion, contrast-induced nephropathy, or amputation. Contemporary PVI can be performed in elderly patients with high procedural and technical success with low rates of periprocedural complications including mortality. These findings may support the notion of using PVI as a preferred revascularization strategy in the treatment of severe peripheral arterial disease in the elderly population. Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Characterizing stroke lesions using digital templates and lesion quantification tools in a web-based imaging informatics system for a large-scale stroke rehabilitation clinical trial

NASA Astrophysics Data System (ADS)

Wang, Ximing; Edwardson, Matthew; Dromerick, Alexander; Winstein, Carolee; Wang, Jing; Liu, Brent

2015-03-01

Previously, we presented an Interdisciplinary Comprehensive Arm Rehabilitation Evaluation (ICARE) imaging informatics system that supports a large-scale phase III stroke rehabilitation trial. The ePR system is capable of displaying anonymized patient imaging studies and reports, and the system is accessible to multiple clinical trial sites and users across the United States via the web. However, the prior multicenter stroke rehabilitation trials lack any significant neuroimaging analysis infrastructure. In stroke related clinical trials, identification of the stroke lesion characteristics can be meaningful as recent research shows that lesion characteristics are related to stroke scale and functional recovery after stroke. To facilitate the stroke clinical trials, we hope to gain insight into specific lesion characteristics, such as vascular territory, for patients enrolled into large stroke rehabilitation trials. To enhance the system's capability for data analysis and data reporting, we have integrated new features with the system: a digital brain template display, a lesion quantification tool and a digital case report form. The digital brain templates are compiled from published vascular territory templates at each of 5 angles of incidence. These templates were updated to include territories in the brainstem using a vascular territory atlas and the Medical Image Processing, Analysis and Visualization (MIPAV) tool. The digital templates are displayed for side-by-side comparisons and transparent template overlay onto patients' images in the image viewer. The lesion quantification tool quantifies planimetric lesion area from user-defined contour. The digital case report form stores user input into a database, then displays contents in the interface to allow for reviewing, editing, and new inputs. In sum, the newly integrated system features provide the user with readily-accessible web-based tools to identify the vascular territory involved, estimate lesion area, and store these results in a web-based digital format.

Hemodialysis Access Usage Patterns in the Incident Dialysis Year and Associated Catheter-Related Complications

PubMed Central

Xue, Hui; Ix, Joachim H.; Wang, Weiling; Brunelli, Steven M.; Lazarus, Michael; Hakim, Raymond; Lacson, Eduardo

2012-01-01

Background Hemodialysis(HD) access is considered a critical and actionable determinant of morbidity, with a growing literature suggesting that initial HD access type is an important marker of long term outcomes. Accordingly, we examined HD access during the incident dialysis period, focusing on infection risk and successful fistula creation over the first dialysis year. Study Design Longitudinal cohort Setting & Participants All United States adults admitted to Fresenius Medical Care North America facilities within 15 days of first maintenance dialysis session between January 1 and December 31, 2007. Predictor Vascular access type at HD initiation Outcomes Vascular access type at 90 days and at the end of the first year on HD, bloodstream infection within the first year by access type, and catheter complication rate. Results Amongst the 25,003 incident dialysis patients studied, 19,622(78.5%) initiated dialysis with a catheter, 4,151(16.6%) with a fistula, and 1,230(4.9%) with a graft. At 90 days, 14,105(69.7%) had a catheter, 4432(21.9%) patients had a fistula, and 1705(8.4%) had a graft. Functioning fistulas and grafts at dialysis initiation had first year failure rates of 10% and 15%, respectively. Grafts were seldom replaced by fistulas (3%), while 7,064 (47.6%) of all patients who initiated with a catheter alone still had only a catheter at 1 year. Overall, 3,327 (13.3%) patients had at least one positive blood culture during follow-up, with the risk being similar between fistula and graft groups, but approximately 3-fold higher in patients with a catheter (p<0.001 for either comparison). Nearly one in three catheters (32.5%) will require TPA use by median time of 41 days, with 59% requiring more than one TPA administration. Limitations Potential underestimation of bacteremia because follow-up blood culture results did not include samples sent to local laboratories. Conclusions Among a large and representative population of incident US dialysis patients, catheter use remains very high over the first year of hemodialysis care, and is associated with high mechanical complication and blood stream infection rates. PMID:23159234

Impact of the shape of the implantable ports on their efficiency of flow (injection and flushing)

PubMed Central

Guiffant, Gérard; Flaud, Patrice; Durussel, Jean Jacques; Merckx, Jacques

2014-01-01

Now widely used, totally implantable venous access devices allow mid- and long-term, frequent, repeated, or continuous injection of therapeutic products by vascular, cavitary, or perineural access. The effective flushing of these devices is a key factor that ensures their long-lasting use. We present experimental results and a numerical simulation to demonstrate that the implementation of rounded edge wall cavities improves flushing efficiency. We use the same approaches to suggest that the deposit amount may be reduced by the use of rounded edge wall cavities. PMID:25258561

Origins of native vascular plants of Antarctica: comments from a historical phytogeography viewpoint.

PubMed

Mosyakin, S L; Bezusko, L G; Mosyakin, A S

2007-01-01

The article provides an overview of the problem of origin of the only native vascular plants of Antarctica, Deschampsia antartica (Poaceae) and Colobanthus quitensis (Caryophyllaceae), from the viewpoint of modern historical phytogeography and related fields of science. Some authors suggested the Tertiary relict status of these plants in Antarctica, while others favour their recent Holocene immigration. Direct data (fossil or molecular genetic ones) for solving this controversy is still lacking. However, there is no convincing evidence supporting the Tertiary relict status of these plants in Antarctica. Most probably D. antarctica and C. quitensis migrated to Antarctica in the Holocene or Late Pleistocene (last interglacial?) through bird-aided long-distance dispersal. It should be critically tested by (1) appropriate methods of molecular phylogeography, (2) molecular clock methods, if feasible, (3) direct paleobotanical studies, (4) paleoclimatic reconstructions, and (5) comparison with cases of taxa with similar distribution/dispersal patterns. The problem of the origin of Antarctic vascular plants is a perfect model for integration of modern methods of molecular phylogeography and phylogenetics, population biology, paleobiology and paleogeography for solving a long-standing enigma of historical plant geography and evolution.

A public health perspective to environmental barriers and accessibility problems for senior citizens living in ordinary housing.

PubMed

Granbom, Marianne; Iwarsson, Susanne; Kylberg, Marianne; Pettersson, Cecilia; Slaug, Björn

2016-08-11

Housing environments that hinder performance of daily activities and impede participation in social life have negative health consequences particularly for the older segment of the population. From a public health perspective accessible housing that supports active and healthy ageing is therefore crucial. The objective of the present study was to make an inventory of environmental barriers and investigate accessibility problems in the ordinary housing stock in Sweden as related to the functional capacity of senior citizens. Particular attention was paid to differences between housing types and building periods and to identify environmental barriers generating the most accessibility problems for sub-groups of senior citizens. Data on environmental barriers in dwellings from three databases on housing and health in old age was analysed (N = 1021). Four functional profiles representing large groups of senior citizens were used in analyses of the magnitude and severity of potential accessibility problems. Differences in terms of type of housing and building period were examined. High proportions of one-family houses as well as multi-dwellings had substantial numbers of environmental barriers, with significantly lower numbers in later building periods. Accessibility problems occurred already for senior citizens with few functional limitations, but more profound for those dependent on mobility devices. The most problematic housing sections were entrances in one-family houses and kitchens of multi-dwellings. Despite a high housing standard in the Swedish ordinary housing stock the results show substantial accessibility problems for senior citizens with functional limitations. To make housing accessible large-scale and systematic efforts are required.

Vascular access in critical limb ischemia.

PubMed

Kang, Won Yu; Campia, Umberto; Ota, Hideaki; Didier, Romain J; Negi, Smita I; Kiramijyan, Sarkis; Koifman, Edward; Baker, Nevin C; Magalhaes, Marco A; Lipinski, Michael J; Escarcega, Ricardo O; Torguson, Rebecca; Waksman, Ron; Bernardo, Nelson L

2016-01-01

Currently, percutaneous endovascular intervention is considered a first line of therapy for treating patients with critical limb ischemia. As the result of remarkable development of techniques and technologies, percutaneous endovascular intervention has led to rates of limb salvage comparable to those achieved with bypass surgery, with fewer complications, even in the presence of lower rates of long-term patency. Currently, interventionalists have a multiplicity of access routes including smaller arteries, with both antegrade and retrograde approaches. Therefore, the choice of the optimal access site has become an integral part of the success of the percutaneous intervention. By understanding the technical aspects, as well as the advantages and limitations of each approach, the interventionalists can improve clinical outcomes in patients with severe peripheral arterial disease. This article reviews the access routes in critical limb ischemia, their advantages and disadvantages, and the clinical outcomes of each. Copyright © 2016 Elsevier Inc. All rights reserved.

A primer on intraosseous access: History, clinical considerations, and current devices.

PubMed

Burgert, James M

2016-01-01

Intraosseous (IO) access is a method recommended by the American Heart Association and the European Resuscitation Council to administer resuscitative drugs and fluids when intravenous (IV) access cannot be rapidly or easily obtained. Many clinicians have limited knowledge or experience with the IO route. The purpose of this review was to provide the reader with a succinct review of the history, clinical considerations, and devices associated with IO access. Narrative review. University-based academic research cell. Not applicable. Not applicable. IO access is a lifesaving bridge to definitive vascular access that may be considered when an IV cannot be rapidly attained and the patient's outcome may be negatively affected without prompt circulatory access. The IO route has few contraindications for use and a low rate of serious complications. Multiple manual and powered devices that may be placed in several anatomic sites are commercially available. All clinicians who provide acute care or respond to cardiovascular emergencies should obtain training and maintain proficiency in placing and using IO devices as the IO route is recommended by the major resuscitation organizations as the preferred route of infusion when rapid, reliable IV access is unavailable.

History and conceptual developments in vascular biology and angiogenesis research: a personal view.

PubMed

Bikfalvi, Andreas

2017-11-01

Vascular biology is an important scientific domain that has gradually penetrated many medical and scientific fields. Scientists are most often focused on present problems in their daily scientific work and lack awareness regarding the evolution of their domain throughout history and of how philosophical issues are related to their research field. In this article, I provide a personal view with an attempt to conceptualize vascular development research that articulates lessons taken from history, philosophy, biology and medicine. I discuss selected aspects related to the history and the philosophy of sciences that can be extracted from the study of vascular development and how conceptual progress in this research field has been made. I will analyze paradigm shifts, cross-fertilization of different fields, technological advances and its impact on angiogenesis and discuss issues related to evolutionary biology, proximity of different molecular systems and scientific methodologies. Finally, I discuss briefly my views where the field is heading in the future.

Study of the therapeutic benefit of cationic copolymer administration to vascular endothelium under mechanical stress

PubMed Central

Giantsos-Adams, Kristina; Lopez-Quintero, Veronica; Kopeckova, Pavla; Kopecek, Jindrich; Tarbell, John M.; Dull, Randal

2015-01-01

Pulmonary edema and the associated increases in vascular permeability continue to represent a significant clinical problem in the intensive care setting, with no current treatment modality other than supportive care and mechanical ventilation. Therapeutic compound(s) capable of attenuating changes in vascular barrier function would represent a significant advance in critical care medicine. We have previously reported the development of HPMA-based copolymers, targeted to endothelial glycocalyx that are able to enhance barrier function. In this work, we report the refinement of copolymer design and extend our physiological studies todemonstrate that the polymers: 1) reduce both shear stress and pressure-mediated increase in hydraulic conductivity, 2) reduce nitric oxide production in response to elevated hydrostatic pressure and, 3) reduce the capillary filtration coefficient (Kfc) in an isolated perfused mouse lung model. These copolymers represent an important tool for use in mechanotransduction research and a novel strategy for developing clinically useful copolymers for the treatment of vascular permeability. PMID:20932573

Deep skin structural and microcirculation imaging with extended-focus OCT

NASA Astrophysics Data System (ADS)

Blatter, Cedric; Grajciar, Branislav; Huber, Robert; Leitgeb, Rainer A.

2012-02-01

We present an extended focus OCT system for dermatologic applications that maintains high lateral resolution over a large depth range by using Bessel beam illumination. More, Bessel beams exhibit a self-reconstruction property that is particularly useful to avoid shadowing from surface structures such as hairs. High lateral resolution and high-speed measurement, thanks to a rapidly tuning swept source, allows not only for imaging of small skin structures in depth but also for comprehensive visualization of the small capillary network within the human skin in-vivo. We use this information for studying temporal vaso-responses to hypothermia. In contrast to other perfusion imaging methods such as laser Doppler imaging (LDI), OCT gives specific access to vascular responses in different vascular beds in depth.

Autonomy and Housing Accessibility Among Powered Mobility Device Users

PubMed Central

Brandt, Åse; Lexell, Eva Månsson; Iwarsson, Susanne

2015-01-01

OBJECTIVE. To describe environmental barriers, accessibility problems, and powered mobility device (PMD) users’ autonomy indoors and outdoors; to determine the home environmental barriers that generated the most housing accessibility problems indoors, at entrances, and in the close exterior surroundings; and to examine personal factors and environmental components and their association with indoor and outdoor autonomy. METHOD. This cross-sectional study was based on data collected from a sample of 48 PMD users with a spinal cord injury (SCI) using the Impact of Participation and Autonomy and the Housing Enabler instruments. Descriptive statistics and logistic regression were used. RESULTS. More years living with SCI predicted less restriction in autonomy indoors, whereas more functional limitations and accessibility problems related to entrance doors predicted more restriction in autonomy outdoors. CONCLUSION. To enable optimized PMD use, practitioners must pay attention to the relationship between client autonomy and housing accessibility problems. PMID:26356666

2000 RSNA annual oration in diagnostic radiology: The future of interventional radiology.

PubMed

Becker, G J

2001-08-01

Origins in imaging, procedural emphasis, and dependence on innovation characterize interventional radiology, which will continue as the field of image-guided minimally invasive therapies. A steady supply of innovators will be needed. Current workforce shortages demand that this problem be addressed and in an ongoing fashion. Interventional radiology's major identity problem will require multiple corrective measures, including a name change. Diagnostic radiologists must fully embrace the concept of the dedicated interventionalist. Interspecialty turf battles will continue, especially with cardiologists and vascular surgeons. To advance the discipline, interventional radiologists must remain involved in cutting-edge therapies such as endograft repair of aortic aneurysms and carotid stent placement. As the population ages, interventionalists will experience a shift toward a greater emphasis on cancer treatment. Political agendas and public pressure will improve access to care and result in managed health care reforms. Academic centers will continue to witness a decline in time and resources available to pursue academic missions. The public outcry for accountability will result in systems changes aimed at reducing errors and process changes in the way physicians are trained, certified, and monitored. Evidence-based medicine will be the watchword of this century. Interventional radiology will maintain its role through development of methods for delivery of genes, gene products, and drugs to specific target sites; control of angiogenesis and other biologic processes; and noninvasive image-guided delivery of various forms of energy for ablation.

Disabling Outcomes After Peripheral Vascular Catheter Insertion in a Newborn Patient: A Case of Medical Liability?

PubMed Central

Bolcato, Matteo; Russo, Marianna; Donadello, Damiano; Rodriguez, Daniele; Aprile, Anna

2017-01-01

Patient: Female, newborn Final Diagnosis: Loss of falange of the hand Symptoms: Manual disability • Pain Medication: Ampicilline Clinical Procedure: Insert vascular catheter Specialty: Forenscic Medicine Objective: Rare disease Background: The positioning of peripheral venous catheters (PVC) is an invasive procedure commonly performed in pediatrics hospital wards to obtain vascular access for the administration of fluids, medications and other intravenous (IV) therapies. Many studies exist about management of peripheral venous access in adults. On the contrary, scientific evidence on the management of this procedure in children and newborns, especially regarding the optimal duration of infusion and the possible related side effects, is still poor. To minimize the risk of phlebitis, the guidelines of the US Centers for Disease Control and Prevention suggest the replacement of the catheter every 72–96 hours in adult patients, while in pediatric patients the catheter can remain in place for the entire duration of the IV therapy, unless complications arise. Case Report: In the presented case, after the positioning of a PVC in a newborn, no clear signs/symptoms of phlebitis were registered before the sixth day and, despite the immediate removal of the catheter, the thrombotic process, secondary to phlebitis, was already occurring, causing serious and permanent disabling outcomes, susceptible to legal medical evaluation and financial compensation. Conclusions: The knowledge of this case is particularly interesting to clinicians working in the field of neonatal care and to clinical risk management services inside hospital structures, since similar cases may be the source of requests for extremely high financial compensations due to medical liability. PMID:29056746

Catheter-based tricuspid valve replacement: first experimental data of a newly designed bileaflet stent graft prosthesis.

PubMed

Lausberg, Henning F; Gryszkiewicz, Rafal; Kuetting, Maximilian; Baumgaertner, Moritz; Centola, Marcos; Wendel, Hans-Peter; Nowak-Machen, Martina; Schibilsky, David; Kruger, Tobias; Schlensak, Christian

2017-07-01

Moderate or severe degree tricuspid valve regurgitation (TVR) is associated with high rates of morbidity and mortality. Surgical correction as the only therapeutic option offers unsatisfactory results. Recently, several interventional procedures have been introduced clinically in a limited cohort. We present our initial experiments with an innovative interventional valved stent graft for treatment of TVR. A newly designed porcine pericardium-covered nitinol stent graft with a lateral bicuspid valve was adapted to size in a cadaver study. After haemodynamic testing in an ex vivo perfusion setup, vascular access, valve delivery and function were investigated in an ovine animal model ( n  = 7). The device was implanted successfully in all animals. Vascular access was established surgically via the femoral vein without any vascular complications. Angiography demonstrated the correct position of the device with proper sealing of both venae cavae in 6 animals. In 1 extremely large animal, the position of the device was considered too cranial but still acceptable. Correct valve function was verified in all animals by both angiography and echocardiography. There were no persistent arrhythmias other than during valve implant. All animals survived the implant procedure and were sacrificed electively. This study demonstrated that this new valved stent graft could be delivered safely with correct positioning and valve function in this ovine model. Further long-term studies in animals implanted with the device after creation of tricuspid regurgitation are necessary to prove the haemodynamic benefit of this procedure. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

The possibility of renal function recovery in chronic hemodialysis patients should not be overlooked: Single center experience.

PubMed

Letachowicz, Krzysztof; Madziarska, Katarzyna; Letachowicz, Waldemar; Krajewska, Magdalena; Penar, Józef; Kusztal, Mariusz; Gołębiowski, Tomasz; Weyde, Wacław; Klinger, Marian

2016-04-01

Chronic hemodialysis is implemented when irreversible loss of kidney function occurs. Sometimes renal recovery is overlooked. From January 2005 to December 2014, we identified 28 patients hemodialyzed for more than 3 months who had renal replacement therapy discontinued. The group consisted of 17 (57.7%) males and 11 (42.3%) females. Patients were 18-87 years old. Time of hemodialysis ranged from 3 to 97 months. Of note, 14 (50%) patients were referred from local dialysis units for solution of vascular access problems. In 13 (46.2%) patients dialysis was abandoned within the first 6 months, in 5 (17.8%) patients between 6 and 12 months, and in 10 (35.7%) patients beyond 12 months. Estimated dialysis-free survival was 94.4% (SE 0.054) and 82% (SE 0.095) at 12 and 24 months, respectively. All physicians must be aware of possible kidney function improvement. In patients with preserved diuresis fall in periodical urea or creatinine measurements might be a sign of renal recovery. © 2015 International Society for Hemodialysis.

History of functional neurosurgery.

PubMed

Iskandar, B J; Nashold, B S

1995-01-01

Whereas in the early days of evil spirits, electric catfish, and phrenology, functional neurosurgery was based on crude observations and dogma, the progress made in neurophysiology at the turn of the century gave the field a strong scientific foundation. Subsequently, the advent of stereotaxis allowed access to deep brain regions and contributed an element of precision. Future directions include the development of frameless stereotaxy; the use of MRI-generated anatomic data, which would circumvent the serious problem of individual variations seen with standard brain atlases; the introduction of various chemicals into brain structures, in an attempt to influence neurochemically mediated disease processes; and finally, the use of the promising techniques of neural transplantation. On hearing of Penfield's intraoperative brain stimulations, Sherrington commented: "It must be great fun to have the physiological preparation speak to you." The idea of therapeutic neurophysiologic interventions is appealing, especially because many disorders show no obvious treatable pathologic cause (e.g., tumor, vascular malformation). As stereotactic technology becomes less cumbersome and more precise, more sophisticated in vivo neurophysiologic preparations become possible. In turn, as our understanding of nervous system physiology grows, our ability to understand pathophysiology and treat disease processes increases.

Advantages and Disadvantages of the Amplatzer Vascular Plug IV in Visceral Embolization: Report of 50 Placements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pech, Maciej, E-mail: maciej.pech@med.ovgu.de; Mohnike, Konrad; Wieners, Gero

2011-10-15

Purpose: We describe our initial clinical experience in artificial embolization with the Amplatzer Vascular Plug IV (VP IV), a further development of the Vascular Plug family already in routine use. Methods: Results from 50 embolization procedures conducted with the VP IV in 44 patients are summarized. Results: All 50 embolizations were successful, although two required the technique to be modified because of problems with jamming of the screw thread and thus with disconnection of the plug. This was associated with large branching angles. Conclusions: With experience, the VP IV can be used safely and effectively, and it expands the spectrummore » of possible embolizations in interventional radiology. Its greatest disadvantage is its relatively poor positional controllability.« less

[Bilateral spontaneous carotid-cavernous fistula revealing Ehler-Danlos disease].

PubMed

Girardin, M; Puzenat, E; Humbert, P; Aubin, F

2013-04-01

A 34-year-old woman with an extensive surgical history developed two spontaneous carotido-cavernous fistula bilaterally. Skin examination revealed an acrogeric form of vascular Ehlers-Danlos syndrome and this diagnosis was confirmed by genetic analysis. Vascular Ehlers-Danlos syndrome is a rare autosomal dominant genetic disease that may be suspected on the grounds of clinical symptoms. Severe complications can occur in early life and are associated with a high mortality rate. The prognosis of vascular Ehlers-Danlos syndrome has been radically changed by the use of beta-blockers. The originality of our observation lies in the long time to onset of the initial complications in the absence of any problems during the numerous operations undergone by the patient, as well as the two childbirths. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Transcatheter Embolotherapy with N-Butyl Cyanoacrylate for Ectopic Varices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choi, Jin Woo; Kim, Hyo-Cheol, E-mail: angiointervention@gmail.com; Jae, Hwan Jun, E-mail: jaemdphd@gmail.com

PurposeTo address technical feasibility and clinical outcome of transcatheter embolotherapy with N-butyl cyanoacrylate (NBCA) for bleeding ectopic varices.MethodsThe institutional review board approved this retrospective study and waived informed consent. From January 2004 to June 2013, a total of 12 consecutive patients received transcatheter embolotherapy using NBCA for bleeding ectopic varices in our institute. Clinical and radiologic features of the endovascular procedures were comprehensively reviewed.ResultsPreprocedural computed tomography images revealed ectopic varices in the jejunum (n = 7), stoma (n = 2), rectum (n = 2), and duodenum (n = 1). The 12 procedures consisted of solitary embolotherapy (n = 8) and embolotherapy with portal decompression (main portal vein stenting in 3,more » transjugular intrahepatic portosystemic shunt in 1). With regard to vascular access, percutaneous transhepatic access (n = 7), transsplenic access (n = 4), and transjugular intrahepatic portosystemic shunt tract (n = 1) were used. There was no failure in either the embolotherapy or the vascular accesses (technical success rate, 100 %). Two patients died within 1 month from the procedure from preexisting fatal medical conditions. Only one patient, with a large varix that had been partially embolized by using coils and NBCA, underwent rebleeding 5.5 months after the procedure. The patient was retreated with NBCA and did not undergo any bleeding afterward for a follow-up period of 2.5 months. The remaining nine patients did not experience rebleeding during the follow-up periods (range 1.5–33.2 months).ConclusionTranscatheter embolotherapy using NBCA can be a useful option for bleeding ectopic varices.« less

Hand dominance in intravenous drug using patients does not affect peripheral venous access sites identified by ultrasound.

PubMed

Kaban, Nicole L; Avitabile, Nicholas C; Siadecki, Sebastian D; Saul, Turandot

2016-06-01

The peripheral veins in the arms and forearms of patients with a history of intravenous (IV) drug use may be sclerosed, calcified, or collapsed due to damage from previous injections. These patients may consequently require alternative, more invasive types of vascular access including central venous or intraosseous catheters. We investigated the relationship between hand dominance and the presence of patent upper extremity (UE) veins specifically in patients with a history of IV drug-use. We predicted that injection into the non-dominant UE would occur with a higher frequency than the dominant UE, leading to fewer damaged veins in the dominant UE. If hand dominance affects which upper extremity has more patent veins, providers could focus their first vascular access attempt on the dominant upper extremity. Adult patients were approached for enrollment if they provided a history of IV drug use into one of their upper extremities. Each upper extremity was examined with a high frequency linear transducer in 3 areas: the antecubital crease, forearm and the proximal arm. The number of fully compressible veins ≥1.8 mm in diameter was recorded for each location. The mean vein difference between the numbers of veins in the dominant versus the non-dominant UE was -1.5789. At a .05 significance level, there was insufficient evidence to suggest the number of compressible veins between patients' dominant and non-dominant arms was significantly different (P = .0872.) The number of compressible veins visualized with ultrasound was not greater in the dominant upper extremity as expected. Practitioners may gain more information about potential peripheral venous access sites by asking patients their previous injection practice patterns. Copyright © 2016 Elsevier Inc. All rights reserved.

Melon Resistance to Cucurbit yellow stunting disorder virus Is Characterized by Reduced Virus Accumulation.

PubMed

Marco, Cristina F; Aguilar, Juan M; Abad, Jesús; Gómez-Guillamón, María Luisa; Aranda, Miguel A

2003-07-01

ABSTRACT The pattern of accumulation of Cucurbit yellow stunting disorder virus (CYSDV; genus Crinivirus, family Closteroviridae) RNA has been analyzed in several cucurbit accessions. In susceptible accessions of melon (Cucumis melo), cucumber (Cucumis sativus), marrow (Cucurbita maxima), and squash (Cucurbita pepo), CYSDV RNA accumulation peaked during the first to second week postinoculation in the first to third leaf above the inoculated one; younger leaves showed very low or undetectable levels of CYSDV. Three melon accessions previously shown to remain asymptomatic after CYSDV inoculation under natural conditions were also assayed for their susceptibility to CYSDV. Hybridization and reverse transcription-polymerase chain reaction (RT-PCR) analysis of noninoculated leaves showed that only one of these, C-105, remained virus-free for up to 6 weeks after whitefly inoculation. In this accession, very low CYSDV levels were detected by RT-PCR in whitefly-inoculated leaves, and therefore, multiplication or spread of CYSDV in C-105 plants appeared to remain restricted to the inoculated leaves. When C-105 plants were graft inoculated, CYSDV RNA could be detected in phloem tissues, but the systemic colonization of C-105 by CYSDV upon graft inoculation seemed to be seriously impeded. Additionally, in situ hybridization experiments showed that, after C-105 graft inoculation, only a portion of the vascular bundles in petioles and stems were colonized by CYSDV and virus could not be found in leaf veins. RT-PCR experiments using primers to specifically detect negative-sense CYSDV RNA were carried out and showed that CYSDV replication took place in graft-inoculated C-105 scions. Therefore, the resistance mechanism may involve a restriction of the virus movement in the vascular system of the plants and/or prevention of high levels of virus accumulation.

Management of Central Venous Access Device-Associated Skin Impairment: An Evidence-Based Algorithm.

PubMed

Broadhurst, Daphne; Moureau, Nancy; Ullman, Amanda J

Patients relying on central venous access devices (CVADs) for treatment are frequently complex. Many have multiple comorbid conditions, including renal impairment, nutritional deficiencies, hematologic disorders, or cancer. These conditions can impair the skin surrounding the CVAD insertion site, resulting in an increased likelihood of skin damage when standard CVAD management practices are employed. Supported by the World Congress of Vascular Access (WoCoVA), developed an evidence- and consensus-based algorithm to improve CVAD-associated skin impairment (CASI) identification and diagnosis, guide clinical decision-making, and improve clinician confidence in managing CASI. A scoping review of relevant literature surrounding CASI management was undertaken March 2014, and results were distributed to an international advisory panel. A CASI algorithm was developed by an international advisory panel of clinicians with expertise in wounds, vascular access, pediatrics, geriatric care, home care, intensive care, infection control and acute care, using a 2-phase, modified Delphi technique. The algorithm focuses on identification and treatment of skin injury, exit site infection, noninfectious exudate, and skin irritation/contact dermatitis. It comprised 3 domains: assessment, skin protection, and patient comfort. External validation of the algorithm was achieved by prospective pre- and posttest design, using clinical scenarios and self-reported clinician confidence (Likert scale), and incorporating algorithm feasibility and face validity endpoints. The CASI algorithm was found to significantly increase participants' confidence in the assessment and management of skin injury (P = .002), skin irritation/contact dermatitis (P = .001), and noninfectious exudate (P < .01). A majority of participants reported the algorithm as easy to understand (24/25; 96%), containing all necessary information (24/25; 96%). Twenty-four of 25 (96%) stated that they would recommend the tool to guide management of CASI.

Subject Access Problems of Different Types of OPAC Users Or, the Double Challenge.

ERIC Educational Resources Information Center

Cochrane, Pauline A.

1989-01-01

Reviews the problems of users of online public access catalogs and argues that it is necessary to think of all searching problems as systems problems rather than user failures, and to concentrate research in the area of systems enhancements. A list of improved tools needed for subject searching in online catalogs is identified. (CLB)

High School Student Information Access and Engineering Design Performance

ERIC Educational Resources Information Center

Mentzer, Nathan

2014-01-01

Developing solutions to engineering design problems requires access to information. Research has shown that appropriately accessing and using information in the design process improves solution quality. This quasi-experimental study provides two groups of high school students with a design problem in a three hour design experience. One group has…

[Free tissue transfers with lengthening of vascular pedicle using interpositional vein grafts. About 10 cases].

PubMed

Yeo, S; Perrot, P; Duteille, F

2010-04-01

The realization of free flaps with lack of reliable vessels nearby the loss of substance is a difficult problem for plastic surgeons. We report 10 cases of free tissue transfers with a one-stage technique lengthening the vascular pedicle of the free flap with interpositional vein grafts. Taking into consideration the good results and the low rate of morbidity, the authors emphasize the use of this technique rather than a two-stage procedure. Copyright 2009 Elsevier Masson SAS. All rights reserved.

Information Graphic Classification, Decomposition and Alternative Representation

ERIC Educational Resources Information Center

Gao, Jinglun

2012-01-01

This thesis work is mainly focused on two problems related to improving accessibility of information graphics for visually impaired users. The first problem is automated analysis of information graphics for information extraction and the second problem is multi-modal representations for accessibility. Information graphics are graphical…

Immunity at Cauliflower Hydathodes Controls Systemic Infection by Xanthomonas campestris pv campestris1

PubMed Central

Cerutti, Aude; Jauneau, Alain; Auriac, Marie-Christine; Lauber, Emmanuelle; Martinez, Yves; Chiarenza, Serge

2017-01-01

Hydathodes are water pores found on leaves of a wide range of vascular plants and are the sites of guttation. We report here on the detailed anatomy of cauliflower (Brassica oleracea) and Arabidopsis (Arabidopsis thaliana) hydathodes. Hydathode surface presents pores resembling stomata giving access to large cavities. Beneath, the epithem is composed of a lacunar and highly vascularized parenchyma offering a direct connection between leaf surface and xylem vessels. Arabidopsis hydathode pores were responsive to ABA and light similar to stomata. The flg22 flagellin peptide, a well-characterized elicitor of plant basal immunity, did not induce closure of hydathode pores in contrast to stomata. Because hydathodes are natural infection routes for several pathogens, we investigated hydathode infection by the adapted vascular phytopathogenic bacterium Xanthomonas campestris pv campestris (Xcc), the causal agent of black rot disease of Brassicaceae. Microscopic observations of hydathodes six days postinoculation indicated a digestion of the epithem cells and a high bacterial multiplication. Postinvasive immunity was shown to limit pathogen growth in the epithem and is actively suppressed by the type III secretion system and its effector proteins. Altogether, these results give a detailed anatomic description of Brassicaceae hydathodes and highlight the efficient use of this tissue as an initial niche for subsequent vascular systemic dissemination of Xcc in distant plant tissues. PMID:28184011

Relative vascular permeability and vascularity across different regions of the rat nasal mucosa: implications for nasal physiology and drug delivery

PubMed Central

Kumar, Niyanta N.; Gautam, Mohan; Lochhead, Jeffrey J.; Wolak, Daniel J.; Ithapu, Vamsi; Singh, Vikas; Thorne, Robert G.

2016-01-01

Intranasal administration provides a non-invasive drug delivery route that has been proposed to target macromolecules either to the brain via direct extracellular cranial nerve-associated pathways or to the periphery via absorption into the systemic circulation. Delivering drugs to nasal regions that have lower vascular density and/or permeability may allow more drug to access the extracellular cranial nerve-associated pathways and therefore favor delivery to the brain. However, relative vascular permeabilities of the different nasal mucosal sites have not yet been reported. Here, we determined that the relative capillary permeability to hydrophilic macromolecule tracers is significantly greater in nasal respiratory regions than in olfactory regions. Mean capillary density in the nasal mucosa was also approximately 5-fold higher in nasal respiratory regions than in olfactory regions. Applying capillary pore theory and normalization to our permeability data yielded mean pore diameter estimates ranging from 13–17 nm for the nasal respiratory vasculature compared to <10 nm for the vasculature in olfactory regions. The results suggest lymphatic drainage for CNS immune responses may be favored in olfactory regions due to relatively lower clearance to the bloodstream. Lower blood clearance may also provide a reason to target the olfactory area for drug delivery to the brain. PMID:27558973

Successful simultaneous ipsilateral stenting of common iliac artery stenosis and transfemoral aortic valve replacement.

PubMed

Aslan, Abdullah Nabi; Kasapkara, Hacı Ahmet; Sivri, Serkan; Güney, Murat Can; Bozkurt, Engin

2017-01-01

Transcatheter aortic valve replacement (TAVR) was designed to treat elderly patients with severe aortic stenosis at high risk for surgery, and is most commonly performed with retrograde approach through femoral arteries. However, in up to 30% of cases, it is either not possible to use this access route or it is considered to have high risk of vascular injury. Alternative approaches have been described for patients with no suitable femoral access: trans-subclavian, transaortic, or direct aortic access; however, since the introduction of new valves deployed with low-profile delivery systems, another alternative transcatheter approach has been discovered. Presently described is experience in 2 cases in which patients were treated with transfemoral TAVR using Edwards SAPIEN 3 transcatheter heart valves immediately following ipsilateral common iliac artery stenting.

A diabetic foot service established by a department of vascular surgery: an observational study.

PubMed

Williams, Dean T; Majeed, Muhammad U; Shingler, Guy; Akbar, Mohammed J; Adamson, Diane G; Whitaker, Christopher J

2012-07-01

The mechanism by which the multidisciplinary approach to diabetic foot disease reduces amputation rates is unclear. Ischemia, sepsis, and necrosis represent aspects of severe diabetic foot disease amenable to intervention. In 2006, a vascular unit introduced a rapid access service for severe foot disease, augmenting the established community provision. This study aimed to determine whether concurrent changes in amputation rates were observed, and to identify areas that may have influenced outcomes. Unit data prospectively collected during 4 years for patients with lower-limb disease were compared with data retrieved over 2 years before the foot service. Outcome measurements were major amputations, foot surgery, vascular interventions, admissions, and length of stay. Major amputation rates associated with diabetes peaked in 2005 at 24.7/10,000 vs. 1.07/10,000 in 2009; (relative risk = 0.043, 95% confidence interval = 0.006-0.322). The proportion of diabetic to nondiabetic amputations decreased; foot surgery rates also dropped (53.7/10,000 in 2006 vs. 7.5/10,000 in 2009). The number of open revascularization procedures decreased, but the rates of endovascular procedures remained generally constant. Hospital admission rates decreased after initially peaking, and the length of stay was unchanged (16 vs. 15.5 days in 2004 and 2009, respectively). The integration of a vascular unit with community care has been associated with improved outcomes for patients with diabetic foot disease. Improvements were not related to the increased number of vascular procedures or hospitalizations, but did coincide with a greater proportion of patients attending the foot unit. The referral of patients to the unit facilitates the rapid management of severe disease, reducing delays deleterious to outcomes. Copyright © 2012 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.

Differential Responses of Vanilla Accessions to Root Rot and Colonization by Fusarium oxysporum f. sp. radicis-vanillae

PubMed Central

Koyyappurath, Sayuj; Conéjéro, Geneviève; Dijoux, Jean Bernard; Lapeyre-Montès, Fabienne; Jade, Katia; Chiroleu, Frédéric; Gatineau, Frédéric; Verdeil, Jean Luc; Besse, Pascale; Grisoni, Michel

2015-01-01

Root and stem rot (RSR) disease caused by Fusarium oxysporum f. sp. radicis-vanillae (Forv) is the most damaging disease of vanilla (Vanilla planifolia and V. × tahitensis, Orchidaceae). Breeding programs aimed at developing resistant vanilla varieties are hampered by the scarcity of sources of resistance to RSR and insufficient knowledge about the histopathology of Forv. In this work we have (i) identified new genetic resources resistant to RSR including V. planifolia inbreds and vanilla relatives, (ii) thoroughly described the colonization pattern of Forv into selected vanilla accessions, confirming its necrotic non-vascular behavior in roots, and (iii) evidenced the key role played by hypodermis, and particularly lignin deposition onto hypodermal cell walls, for resistance to Forv in two highly resistant vanilla accessions. Two hundred and fifty-four vanilla accessions were evaluated in the field under natural conditions of infection and in controlled conditions using in vitro plants root-dip inoculated by the highly pathogenic isolate Fo072. For the 26 accessions evaluated in both conditions, a high correlation was observed between field evaluation and in vitro assay. The root infection process and plant response of one susceptible and two resistant accessions challenged with Fo072 were studied using wide field and multiphoton microscopy. In susceptible V. planifolia, hyphae penetrated directly into the rhizodermis in the hairy root region then invaded the cortex through the passage cells where it induced plasmolysis, but never reached the vascular region. In the case of the resistant accessions, the penetration was stopped at the hypodermal layer. Anatomical and histochemical observations coupled with spectral analysis of the hypodermis suggested the role of lignin deposition in the resistance to Forv. The thickness of lignin constitutively deposited onto outer cell walls of hypodermis was highly correlated with the level of resistance for 21 accessions tested. The accumulation of p-coumaric and sinapic acids, two phenolic precursors of lignin, was observed in the resistant plants inoculated with Fo072, but not in the susceptible one. Altogether, our analyses enlightened the mechanisms at work in RSR resistant genotypes and should enhance the development of novel breeding strategies aimed at improving the genetic control of RSR of vanilla. PMID:26734032

Comparison of the boomerang wire vascular access management system versus manual compression alone during percutaneous diagnostic and interventional cardiovascular procedures: The boomerang™ wire vascular access management trial II.

PubMed

Goswami, Nilesh J; Smalling, Ronnie G; Sinha, Shantanu; Gammon, Roger S; Ramaiah, Venkatesh G

2016-01-01

To evaluate the use of the Boomerang™ Wire as an adjunct to manual compression (MC) in patients requiring diagnostic (Dx) or interventional (Ix) percutaneous procedures. MC remains the standard of care for closure of femoral artery access sites. Adjunctive use of a device to facilitate closure, reduce time to hemostasis (TTH) and ambulation (TTA) without increasing complication rates could reduce costs and hospital resource demands. The Boomerang™ Trial was a prospective, multicenter, randomized, controlled trial comparing use of the Boomerang™ wire, (Cardiva Medical, Sunnyvale, CA) in conjunction with MC versus MC alone to achieve hemostasis in Dx and Ix patients undergoing percutaneous procedures requiring femoral artery access. Endpoints included TTH, TTA, major, and minor access-site related complications. Subjects were randomized 3:1, Boomerang versus MC. No minor or major device-related adverse events were reported. Nondevice related complication rates were 3 (0.9%) in the Boomerang arm (n = 327) and 1 (0.8%) in MC arm (n = 123). Mean TTH for Boomerang vs. MC was 11.2 ± 4.3 vs. 23.2 ± 11 min for Dx (P < 0.0001) and 13.9 ± 5.4 vs. 38.4 ± 57.3 min for Ix patients (P < 0.0001). Mean TTA for Boomerang vs. MC was 3.3 ± 3.0 vs. 4.5 ± 2.0 hr (P < 0.0001)for Dx and 5.4 ± 3.3 vs. 6.8 ± 3.2 hr (P < 0.0001) for Ix patients. Boomerang™ use, in conjunction with MC, was associated with low rates of complications and demonstrated that Boomerang™ as an adjunct to MC can significantly decrease TTH and TTA after both Dx and Ix procedures. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Microvascular temporalis fascia transfer for penile girth enhancement.

PubMed

Küçükçelebi, A; Ertaş, N M; Aydin, A; Eroğlu, A; Ozmen, E; Velidedeoğlu, H

2001-07-01

The authors report a 44-year-old man with inadequate penile girth that caused psychological problems. Using microvascular temporalis fascia transfer, they achieved satisfactory penile girth enhancement based on reliable vascularity in a single stage.

Atypical use of PICC in infants and small children: a unicentric experience.

PubMed

Bernasconi, Filippo; Zanaboni, Clelia; Dato, Andrea; Dolcino, Andrea; Bevilacqua, Michela; Montagnini, Luigi; Disma, Nicola

2017-11-17

The peripherally inserted central catheters (PICCs) are vascular access devices (VAD) that are increasingly being used in the pediatric population. If a small vein caliber prevents positioning the catheter in the arm, the following step is to position the same catheter in the supraclavicular area, which can be defined as an off-label use or "atypical" approach, first described by Pittiruti. We retrospectively reviewed PICC positioning with puncture-site in the supra-clavicular area ("atypical" PICC insertion) and then tunneled on the chest. Nineteen atypical PICCs were positioned in 18 patients. The median age of patients at the day of implant was 14 months (IQR 3-27 months), and weight 7.5 kg (IQR 4-12 kg). Within this population, 74% of cases scheduled for a typical PICC insertion presented vein caliber too small for this procedure. For this reason, the typical PICC insertion was changed in favor of an atypical PICC procedure. Atypical PICCs were successfully used in 100% of cases without immediate complications. Atypical PICC positioning is a safe and useful alternative to the conventional technique when there is need for a central vascular access device (CVAD) for mid- or long-term therapy.

A national appraisal of haemodialysis vascular access provision in Scotland.

PubMed

Oliver, Scott W; Campbell, Jacqueline; Kingsmore, David B; Kasthuri, Ram; Metcalfe, Wendy; Traynor, Jamie P; Fischbacher-Smith, Denis; Jardine, Alan G; Thomson, Peter C

2017-03-21

Published registry data demonstrate longstanding variation in the utilisation of different vascular access (VA) modalities between Scottish renal units; this may reflect different clinical processes between centres. A comprehensive appraisal was undertaken to understand the processes underpinning VA creation and maintenance across Scotland. A mixed methods approach was utilised. Fifty-two semi-structured interviews were conducted with patients and clinicians in all ten, adult and paediatric, Scottish renal units. Interview transcripts were subjected to thematic analysis. Clinical activity data were prospectively collected for six weeks, and correlated with registry data. VA accounts for a large clinical workload. There was significant inter-centre variation in the utilisation of different VA modalities, and patients described frustrating, dissatisfying experiences. VA creation and maintenance pathways functioned best when nephrologists, surgeons and radiologists were co-located on the same campus with close multi-disciplinary working, protected clinical time, and proactive VA maintenance. No unit routinely measured or discussed procedure outcomes or strategic aspects of their service. Varied clinical outcomes reflected varied clinical processes. Optimised clinical pathways, staff education and measurement of clinical outcomes may improve VA service quality and facilitate safer, more effective, patient-centred care.

The challenge of methicillin-resistant Staphylococcus aureus prevention in hemodialysis therapy.

PubMed

Parker, Mark G; Doebbeling, Bradley N

2012-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) infections have challenged care process and resource utilization in the acute hospital care setting for nearly 30 years. These infections have become important causes of morbidity, mortality, and a source of concern in the primary and emergency care context over the past decade. As individuals receiving recurrent therapy with features of both ambulatory care and acute care, hemodialysis patients are exposed to numerous opportunities for MRSA acquisition. Surprisingly, high prevalence rates for MRSA colonization have been demonstrated for both hemodialysis patients and their care providers. The necessity of vascular access and the persistent high prevalence of endovascular catheter use among patients repeatedly exposed to healthcare settings provide the perfect milieu for the troubling rates of MRSA infection, particularly bloodstream infections, in outpatient dialysis care. Dialysis industry shifts, including increased requirements for compliance and reporting in other areas of dialysis care, tax resources for infection prevention processes. Multifaceted strategies that include reassessment of vascular access care, attention to the interruption of MRSA transmission dynamics, and emphasis on organizational learning processes are needed to accomplish a meaningful reduction in the morbidity, mortality, and cost associated with MRSA infections in dialysis care. © 2011 Wiley Periodicals, Inc.

Predicting drug interactions in addiction treatment.

PubMed

Lucas, Catherine J; Patel, Joanne; Martin, Jennifer H

2017-08-01

It is not uncommon to be treating people with addiction who also have significant other health problems, including heart, renal or liver failure, diabetes and vascular disease. These conditions require regular medications to be taken. This can be a problem for people living with addiction and difficult social circumstances affecting compliance, among other issues. Our perspective provides a summary of general pharmacological factors affecting medicine taking in people with addiction problems, to provide a guide for hospital doctors in this setting. © 2017 Royal Australasian College of Physicians.

Variation in fistula use across dialysis facilities: is it explained by case-mix?

PubMed

Tangri, Navdeep; Moorthi, Ranjani; Tighiouhart, Hocine; Meyer, Klemens B; Miskulin, Dana C

2010-02-01

Arteriovenous fistulas (AVFs) remain the preferred vascular access for hemodialysis patients. Dialysis facilities that fail to meet Centers for Medicare & Medicaid Services goals cite patient case-mix as a reason for low AVF prevalence. This study aimed to determine the magnitude of the variability in AVF usage across dialysis facilities and the extent to which patient case-mix explains it. The vascular access used in 10,112 patients dialyzed at 173 Dialysis Clinic Inc. facilities from October 1 to December 31, 2004, was evaluated. The access in use was considered to be an AVF if it was used for >70% of hemodialysis treatments. Mixed-effects models with a random intercept for dialysis facilities evaluated the effect of facilities on AVF usage. Sequentially adjusted multivariate models measured the extent to which patient factors (case-mix) explain variation across facilities in AVF rates. 3787 patients (38%) were dialyzed using AVFs. There was a significant facility effect: 7.6% of variation in AVF use was attributable to facility. This was reduced to 7.1% after case-mix adjustment. There were no identified specific facility-level factors that explained the interfacility variation. AVF usage varies across dialysis facilities, and patient case-mix did not reduce this variation. In this study, 92% of the total variation in AVF usage was due to patient factors, but most were not measurable. A combination of patient factors and process indicators should be considered in adjudicating facility performance for this quality indicator.

A meta-analysis of the association between diabetic patients and AVF failure in dialysis.

PubMed

Yan, Yan; Ye, Dan; Yang, Liu; Ye, Wen; Zhan, Dandan; Zhang, Li; Xiao, Jun; Zeng, Yan; Chen, Qinkai

2018-11-01

The most preferable vascular access for patients with end-stage renal failure needing hemodialysis is native arteriovenous fistula (AVF) on account of its access longevity, patient morbidity, hospitalization costs, lower risks of infection and fewer incidence of thrombotic complications. Meanwhile, according to National Kidney Foundation (NKF)̸Dialysis Out-comes Quality Initiative (DOQI) guidelines, AVF is more used than before. However, a significant percentage of AVF fails to support dialysis therapy due to lack of adequate maturity. Among all factors, the presence of diabetes mellitus was shown to be one of the risk factors for the development of vascular access failure by some authors. Therefore, this review evaluates the current evidence concerning the correlation of diabetes and AVF failure. A search was conducted using MEDLINE, SCIENCE DIRECT, SPRINGER, WILEY-BLACKWELL, KARGER, EMbase, CNKI and WanFang Data from the establishment time of databases to January 2016. The analysis involved studies that contained subgroups of diabetic patients and compared their outcomes with those of non-diabetic adults. In total, 23 articles were retrieved and included in the review. The meta-analysis revealed a statistically significantly higher rate of AVF failure in diabetic patients compared with non-diabetic patients (OR = 1.682; 95% CI, 1.429-1.981, Test of OR = 1: z = 6.25, p <.001). This review found an increased risk of AVF failure in diabetes patients. If confirmed by further prospective studies, preventive measure should be considered when planning AVF in diabetic patients.

Re-evaluating the Fistula First Initiative in Octogenarians on Hemodialysis.

PubMed

Vachharajani, Tushar J; Moossavi, Shahriar; Jordan, Jean R; Vachharajani, Vidula; Freedman, Barry I; Burkart, John M

2011-07-01

Octogenarians frequently require maintenance hemodialysis (HD) for treatment of stage renal disease ESRD. Although the Fistula First Initiative recommends creating an arteriovenous fistula as the preferred dialysis access method, vascular access selection should be based on life expectancy and functional status at treatment initiation. This is a retrospective analysis of 4-year outpatient data (January 1, 2004 through December 31, 2007) of incident octogenarian dialysis population in an academic institution. Thirty-nine of 268 patients were octogenarians with a mean (± SD) age of 83.4 ± 3.4 years, and 25 were men. Kaplan-Meier survival and Fisher's post hoc statistical analyses were performed. Thirty-seven octogenarian patients selected HD and two selected peritoneal dialysis. Among the 37 HD patients, 29 initiated dialysis with a tunneled cuffed catheter, 6 with an arteriovenous fistula, and 2 with an arteriovenous graft. Three patients regained renal function after an average 112 days and one was lost to follow-up. Of the 33 remaining on HD, 8 required nursing home admission and 25 were discharged home after initiating HD. Among these 33, 19 died and 14 remained on HD at the end of study period. Days on dialysis (mean ± SEM) before death in those discharged to a nursing facility versus home were 52.6 ± 14.7 versus 386.1 ± 90.7 (P < 0.05), respectively. Vascular access planning should include assessment of functional status and life expectancy in octogenarian HD patients.

Financial impact of tertiary care in an academic medical center.

PubMed

Huber, T S; Carlton, L M; O'Hern, D G; Hardt, N S; Keith Ozaki, C; Flynn, T C; Seeger, J M

2000-06-01

To analyze the financial impact of three complex vascular surgical procedures to both an academic hospital and a department of surgery and to examine the potential impact of decreased reimbursements. The cost of providing tertiary care has been implicated as one potential cause of the financial difficulties affecting academic medical centers. Patients undergoing revascularization for chronic mesenteric ischemia, elective thoracoabdominal aortic aneurysm repair, and treatment of infected aortic grafts at the University of Florida were compared with those undergoing elective infrarenal aortic reconstruction and carotid endarterectomy. Hospital costs and profit summaries were obtained from the Clinical Resource Management Office. Departmental costs and profit summary were estimated based on the procedural relative value units (RVUs), the average clinical cost per RVU ($33.12), surgeon charges, and the collection rate for the vascular surgery division (30.2%) obtained from the Faculty Group Practice. Surgeon work effort was analyzed using the procedural work RVUs and the estimated total care time. The analyses were performed for all payors and the subset of Medicare patients, and the potential impact of a 15% reduction in hospital and physician reimbursement was analyzed. Net hospital income was positive for all but one of the tertiary care procedures, but net losses were sustained by the hospital for the mesenteric ischemia and infected aortic graft groups among the Medicare patients. In contrast, the estimated reimbursement to the department of surgery for all payors was insufficient to offset the clinical cost of providing the RVUs for all procedures, and the estimated losses were greater for the Medicare patients alone. The surgeon work effort was dramatically higher for the tertiary care procedures, whereas the reimbursement per work effort was lower. A 15% reduction in reimbursement would result in an estimated net loss to the hospital for each of the tertiary care procedures and would exacerbate the estimated losses to the department. Caring for complex surgical problems is currently profitable to an academic hospital but is associated with marginal losses for a department of surgery. Economic forces resulting from further decreases in hospital and physician reimbursement may limit access to academic medical centers and surgeons for patients with complex surgical problems and may compromise the overall academic mission.

Patterns of perceived barriers to medical care in older adults: a latent class analysis.

PubMed

Thorpe, Joshua M; Thorpe, Carolyn T; Kennelty, Korey A; Pandhi, Nancy

2011-08-03

This study examined multiple dimensions of healthcare access in order to develop a typology of perceived barriers to healthcare access in community-dwelling elderly. Secondary aims were to define distinct classes of older adults with similar perceived healthcare access barriers and to examine predictors of class membership to identify risk factors for poor healthcare access. A sample of 5,465 community-dwelling elderly was drawn from the 2004 wave of the Wisconsin Longitudinal Study. Perceived barriers to healthcare access were measured using items from the Group Health Association of America Consumer Satisfaction Survey. We used latent class analysis to assess the constellation of items measuring perceived barriers in access and multinomial logistic regression to estimate how risk factors affected the probability of membership in the latent barrier classes. Latent class analysis identified four classes of older adults. Class 1 (75% of sample) consisted of individuals with an overall low level of risk for perceived access problems (No Barriers). Class 2 (5%) perceived problems with the availability/accessibility of healthcare providers such as specialists or mental health providers (Availability/Accessibility Barriers). Class 3 (18%) perceived problems with how well their providers' operations arise organized to accommodate their needs and preferences (Accommodation Barriers). Class 4 (2%) perceived problems with all dimension of access (Severe Barriers). Results also revealed that healthcare affordability is a problem shared by members of all three barrier groups, suggesting that older adults with perceived barriers tend to face multiple, co-occurring problems. Compared to those classified into the No Barriers group, those in the Severe Barrier class were more likely to live in a rural county, have no health insurance, have depressive symptomatology, and speech limitations. Those classified into the Availability/Accessibility Barriers group were more likely to live in rural and micropolitan counties, have depressive symptomatology, more chronic conditions, and hearing limitations. Those in the Accommodation group were more likely to have depressive symptomatology and cognitive limitations. The current study identified a typology of perceived barriers in healthcare access in older adults. The identified risk factors for membership in perceived barrier classes could potentially assist healthcare organizations and providers with targeting polices and interventions designed to improve access in their most vulnerable older adult populations, particularly those in rural areas, with functional disabilities, or in poor mental health.

Forseeable Problems in a System of Maximum Access.

ERIC Educational Resources Information Center

Pemberton, John de J., Jr.

A maximum-access cable television system will eliminate some legal and regulatory problems and introduce others. The operator of a system will no longer be responsible for and in control of what is transmitted over his system. With access unlimited and unrestricted, such regulations of content as the "fairness doctrine" and "equal…

An evaluation of three methods of saying "no" to avoid an escalating response class hierarchy.

PubMed

Mace, F Charles; Pratt, Jamie L; Prager, Kevin L; Pritchard, Duncan

2011-01-01

We evaluated the effects of three different methods of denying access to requested high-preference activities on escalating problem behavior. Functional analysis and response class hierarchy (RCH) assessment results indicated that 4 topographies of problem behaviors displayed by a 13-year-old boy with high-functioning autism constituted an RCH maintained by positive (tangible) reinforcement. Identification of the RCH comprised the baseline phase, during which computer access was denied by saying "no" and providing an explanation for the restriction. Two alternative methods of saying "no" were then evaluated. These methods included (a) denying computer access while providing an opportunity to engage in an alternative preferred activity and (b) denying immediate computer access by arranging a contingency between completion of a low-preference task and subsequent computer access. Results indicated that a hierarchy of problem behavior may be identified in the context of denying access to a preferred activity and that it may be possible to prevent occurrences of escalating problem behavior by either presenting alternative options or arranging contingencies when saying "no" to a child's requests.

Retinal vascular segmentation using superpixel-based line operator and its application to vascular topology estimation.

PubMed

Na, Tong; Xie, Jianyang; Zhao, Yitian; Zhao, Yifan; Liu, Yue; Wang, Yongtian; Liu, Jiang

2018-05-09

Automatic methods of analyzing of retinal vascular networks, such as retinal blood vessel detection, vascular network topology estimation, and arteries/veins classification are of great assistance to the ophthalmologist in terms of diagnosis and treatment of a wide spectrum of diseases. We propose a new framework for precisely segmenting retinal vasculatures, constructing retinal vascular network topology, and separating the arteries and veins. A nonlocal total variation inspired Retinex model is employed to remove the image intensity inhomogeneities and relatively poor contrast. For better generalizability and segmentation performance, a superpixel-based line operator is proposed as to distinguish between lines and the edges, thus allowing more tolerance in the position of the respective contours. The concept of dominant sets clustering is adopted to estimate retinal vessel topology and classify the vessel network into arteries and veins. The proposed segmentation method yields competitive results on three public data sets (STARE, DRIVE, and IOSTAR), and it has superior performance when compared with unsupervised segmentation methods, with accuracy of 0.954, 0.957, and 0.964, respectively. The topology estimation approach has been applied to five public databases (DRIVE,STARE, INSPIRE, IOSTAR, and VICAVR) and achieved high accuracy of 0.830, 0.910, 0.915, 0.928, and 0.889, respectively. The accuracies of arteries/veins classification based on the estimated vascular topology on three public databases (INSPIRE, DRIVE and VICAVR) are 0.90.9, 0.910, and 0.907, respectively. The experimental results show that the proposed framework has effectively addressed crossover problem, a bottleneck issue in segmentation and vascular topology reconstruction. The vascular topology information significantly improves the accuracy on arteries/veins classification. © 2018 American Association of Physicists in Medicine.

Prevalence and characteristics of femoral injection among Seattle-area injection drug users.

PubMed

Coffin, Phillip O; Coffin, Lara S; Murphy, Shilo; Jenkins, Lindsay M; Golden, Matthew R

2012-04-01

Injection drug use (IDU) into central veins, most common among long-term IDUs with no other options, can lead to severe infectious, vascular, and traumatic medical consequences. To follow-up on anecdotal reports of femoral vein injection and related medical problems in Seattle, we analyzed data from the annual survey of a community-based syringe exchange program. A total of 276 (81%) of 343 program attendees completed the survey in August 2010. Among 248 IDUs, 66% were male, 78% white, and 86% primarily injected opiates. One hundred respondents (40%) had injected into the femoral vein, 55% of whom were actively doing so, and 58% of whom reported medical complications that they attributed to the practice. Most (66%) used the femoral vein due to difficulty accessing other veins, although 61% reported other veins they could access and 67% reporting using other sites since initiating femoral injection. While injecting into muscle was more frequent among older IDUs with longer injection careers, the prevalence of femoral injection was highest among respondents in their late twenties with 2.5-6 years of injecting drugs. Multivariate analysis demonstrated an increased risk of initiating femoral injection each calendar year after 2007. Injecting into the femoral vein was also associated with white versus other race (odds ratio [OR] 2.7, 95% CI 1.3-5.4) and injection of primarily opiates versus other drugs (OR 6.3, 95% CI 1.2-32.9) and not associated with age, length of IDU career, or a history of injecting into muscle. These findings suggest a secular trend of increasing femoral injection among Seattle-area IDUs with a high rate of related medical problems. Interventions, such as education regarding the hazards of central venous injection and guidance on safe injection into peripheral veins, are needed to minimize the health consequences of femoral injection.

[To be a woman in Africa. On the danger of being a mother. Mortality].

PubMed

Sow, F

1994-10-01

Losing their life while giving birth is a risk that too many women face. More than 33% of all maternal deaths each year occur in Africa, which has less than 12% of the world's population. 30-60% of deaths among African women aged 15-44 are pregnancy-related. Africa has the highest global maternal mortality rate. Its rural areas have an even greater maternal mortality rate. Common causes of maternal death are hemorrhaging, infections, anemia, vascular-renal problems, and abortion complications. In Asia and Africa, girls receive a lower quality and quantity of food than boys. They are also taken for medical care later and when in a more serious state. The lack of attention directed to medical care in early childhood is extended to adolescence, when girls are exposed to the risks of pregnancy and premature births. The culture protects young single mothers less than young wives. Single mothers hide their pregnancy and avoid medical visits. Others try to terminate the pregnancy. In developing countries, 25% of pregnancies are terminated. Menopausal women in Africa also face health risks (e.g., uterine cancer). Few underequipped health centers, lack of personnel, and the relative high cost of medical fees contribute to high maternal mortality rates. In Burkina Faso in 1985, there was only one gynecologist, one midwife, and one maternity hospital for every 225,000, 6250, and 69,230 women of reproductive age, respectively. Access to quality care is still a luxury. The recent devaluation of the CFA franc and the total destabilization of the zaire only exacerbates the awful status of women's lives in Africa. Priorities should be: ensuring prevention and treatment of obstetrical problems, increasing information on pregnancy risks, making family planning services accessible, and improving the quality of care. The most important priority is to let women have control over their own bodies, sexuality, and fertility. An inalienable right of women is to not have to die during childbirth.

Splenic injury during percutaneous nephrolithotomy.

PubMed

Thomas, Anil A; Pierce, Gregory; Walsh, R Matthew; Sands, Mark; Noble, Mark

2009-01-01

Injury to the spleen is a recognized complication during percutaneous renal access due to the close anatomical relationship of the spleen and the left kidney. However, transsplenic renal access is a rare complication of percutaneous nephrolithotomy and can also result in considerable morbidity, often requiring emergent splenectomy. We present our experience with splenic injury during percutaneous nephrolithotomy managed conservatively with the use of a collagen-thrombin hemostatic sealant (D-Stat; Vascular Solutions, Inc., Minneapolis, MN) after delayed removal of the nephrostomy tubes. The patient had an uneventful recovery and was discharged home on postoperative day 6. In select hemodynamically stable patients, nonoperative management with the adjunctive use of hemostatic sealants may be considered.

Using a tailored health information technology- driven intervention to improve health literacy and medication adherence in a Pakistani population with vascular disease (Talking Rx) - study protocol for a randomized controlled trial.

PubMed

Kamal, Ayeesha Kamran; Muqeet, Abdul; Farhat, Kashfa; Khalid, Wardah; Jamil, Anum; Gowani, Ambreen; Muhammad, Aliya Amin; Zaidi, Fabiha; Khan, Danyal; Elahi, Touseef; Sharif, Shahrukh; Raz, Sibtain; Zafar, Taha; Bokhari, Syedah Saira; Rahman, Nasir; Sultan, Fateh Ali Tipoo; Sayani, Saleem; Virani, Salim S

2016-03-05

Vascular disease, manifesting as myocardial infarction and stroke, is a major cause of morbidity and mortality, especially in low- and middle-income countries. Current estimates are that only one in six patients have good adherence to medications and very few have sufficient health literacy. Our aim is to explore the effectiveness and acceptability of Prescription Interactive Voice Response (IVR) Talking Prescriptions (Talking Rx) and SMS reminders in increasing medication adherence and health literacy in Pakistani patients with vascular disease. This is a randomized, controlled, single center trial. Adult participants, with access to a cell phone and a history of vascular disease, taking multiple risk-modifying medications (inclusive of anti-platelets and statins) will be selected from cerebrovascular and cardiovascular clinics. They will be randomized in a 1:1 ratio via a block design to the intervention or the control arm with both groups having access to a helpline number to address their queries in addition to standard of care as per institutional guidelines. Participants in the intervention group will also have access to Interactive Voice Response (IVR) technology tailored to their respective prescriptions in the native language (Urdu) and will have the ability to hear information about their medication dosage, correct use, side effects, mechanism of action and how and why they should use their medication, as many times as they like. Participants in the intervention arm will also receive scheduled SMS messages reminding them to take their medications. The primary outcome measure will be the comparison of the difference in adherence to anti-platelet and statin medication between baseline and at 3-month follow-up in each group measured by the Morisky Medication Adherence Scale. To ascertain the impact of our intervention on health literacy, we will also compare a local content-validated and modified version of Test of Health Literacy in Adults (TOFHLA) between the intervention and the control arm. We estimate that a sample size of 86 participants in each arm will be able to detect a difference of 1 point on the MMAS with a power of 90 % and significance level of 5 %. Accounting for an attrition rate of 15 %, we plan to enroll 100 participants in each arm (total study population = 200). We hypothesize that a linguistically tailored health IT intervention based on IVR and SMS will be associated with an improvement in adherence (to anti-platelet and lipid-lowering medications) and an improvement in health literacy in Pakistani patients with vascular disease. This innovative study will provide early data for the feasibility of the use of IT based prescriptions in an lower middle incorme country setting with limited numeracy and literacy skills. Clinical Trials.gov: NCT02354040 - 2 February 2015.

An evidential approach to problem solving when a large number of knowledge systems is available

NASA Technical Reports Server (NTRS)

Dekorvin, Andre

1989-01-01

Some recent problems are no longer formulated in terms of imprecise facts, missing data or inadequate measuring devices. Instead, questions pertaining to knowledge and information itself arise and can be phrased independently of any particular area of knowledge. The problem considered in the present work is how to model a problem solver that is trying to find the answer to some query. The problem solver has access to a large number of knowledge systems that specialize in diverse features. In this context, feature means an indicator of what the possibilities for the answer are. The knowledge systems should not be accessed more than once, in order to have truly independent sources of information. Moreover, these systems are allowed to run in parallel. Since access might be expensive, it is necessary to construct a management policy for accessing these knowledge systems. To help in the access policy, some control knowledge systems are available. Control knowledge systems have knowledge about the performance parameters status of the knowledge systems. In order to carry out the double goal of estimating what units to access and to answer the given query, diverse pieces of evidence must be fused. The Dempster-Shafer Theory of Evidence is used to pool the knowledge bases.

Brain vascular image enhancement based on gradient adjust with split Bregman

NASA Astrophysics Data System (ADS)

Liang, Xiao; Dong, Di; Hui, Hui; Zhang, Liwen; Fang, Mengjie; Tian, Jie

2016-04-01

Light Sheet Microscopy is a high-resolution fluorescence microscopic technique which enables to observe the mouse brain vascular network clearly with immunostaining. However, micro-vessels are stained with few fluorescence antibodies and their signals are much weaker than large vessels, which make micro-vessels unclear in LSM images. In this work, we developed a vascular image enhancement method to enhance micro-vessel details which should be useful for vessel statistics analysis. Since gradient describes the edge information of the vessel, the main idea of our method is to increase the gradient values of the enhanced image to improve the micro-vessels contrast. Our method contained two steps: 1) calculate the gradient image of LSM image, and then amplify high gradient values of the original image to enhance the vessel edge and suppress low gradient values to remove noises. Then we formulated a new L1-norm regularization optimization problem to find an image with the expected gradient while keeping the main structure information of the original image. 2) The split Bregman iteration method was used to deal with the L1-norm regularization problem and generate the final enhanced image. The main advantage of the split Bregman method is that it has both fast convergence and low memory cost. In order to verify the effectiveness of our method, we applied our method to a series of mouse brain vascular images acquired from a commercial LSM system in our lab. The experimental results showed that our method could greatly enhance micro-vessel edges which were unclear in the original images.

Implementation of radial arterial access for cardiac interventions: a strong case for quality assurance protocols by the nursing staff.

PubMed

Steffenino, Giuseppe; Fabrizi, Mauro De Benedetto; Baralis, Giorgio; Tomatis, Marilena; Mogna, Aldo; Dutto, Monica; Dutto, Maria Stefania; Conte, Laura; Lice, Giulietta; Cavallo, Simona; Porcedda, Brunella

2011-02-01

Radial arterial access is becoming increasingly popular for coronary angiography and angioplasty. The technique is, however, more demanding than femoral arterial access, and hemostasis is not care-free. A quality assurance program was run by our nursing staff, with patient follow-up, to monitor radial arterial access implementation in our laboratory. In 973 consecutive patients, both a hydrophilic sheath and an inflatable bandage for hemostasis were used. Bandage inflation volume and time were both reduced through subsequent data audit and protocol changes (A = 175 patients; B = 297; C = 501). An increase was achieved in the percentage of patients with neither loss of radial pulse nor hematoma of any size (A = 81.3%, B = 90.9%, C = 92.2%, P < 0.001), and no discomfort at all (A = 44.2%, B = 75.1%, C = 89.3%, P < 0.001). Follow-up was available for 965 patients (99%), and in 956, the access site could be re-inspected at least once. There were no vascular complications. Overall, the radial artery pulse was absent at latest follow-up in 0.6% of cases (95% confidence interval 0.21-1.05%). In 460 consecutive patients with complete assessment in protocol C, a palpable arterial pulse was absent in 5% of cases at about 20 h after hemostasis. Barbeau's test was positive in 26.5% of patients (95% confidence interval 22.5-30.6%). They had a significantly lower body weight, a lower systolic blood pressure at hemostasis, and a higher bandage inflation volume; a hematoma of any size and the report of any discomfort were also more frequent. Barbeau's test returned to normal in 30% of them 3-60 days later. Our nurse-led quality assurance program helped us in reducing minor vascular sequelae and improving patient comfort after radial access. Early occlusion of the radial artery as detected by pulse oxymeter is frequent, often reversible, and may be mostly related to trauma/occlusion of the artery during hemostasis. 2011 Italian Federation of Cardiology.

Development of a 3D Soil-Plant-Atmosphere Continuum (SPAC) coupled to a Land Surface Model

NASA Astrophysics Data System (ADS)

Bisht, G.; Riley, W. J.; Lorenzetti, D.; Tang, J.

2015-12-01

Exchange of water between the atmosphere and biosphere via evapotranspiration (ET) influences global hydrological, energy, and biogeochemical cycles. Isotopic analysis has shown that evapotranspiration over the continents is largely dominated by transpiration. Water is taken up from soil by plant roots, transported through the plant's vascular system, and evaporated from the leaves. Yet current Land Surface Models (LSMs) integrated into Earth System Models (ESMs) treat plant roots as passive components. These models distribute the ET sink vertically over the soil column, neglect the vertical pressure distribution along the plant vascular system, and assume that leaves can directly access water from any soil layer within the root zone. Numerous studies have suggested that increased warming due to climate change will lead drought and heat-induced tree mortality. A more mechanistic treatment of water dynamics in the soil-plant-atmosphere continuum (SPAC) is essential for investigating the fate of ecosystems under a warmer climate. In this work, we describe a 3D SPAC model that can be coupled to a LSM. The SPAC model uses the variably saturated Richards equations to simulate water transport. The model uses individual governing equations and constitutive relationships for the various SPAC components (i.e., soil, root, and xylem). Finite volume spatial discretization and backward Euler temporal discretization is used to solve the SPAC model. The Portable, Extensible Toolkit for Scientific Computation (PETSc) is used to numerically integrate the discretized system of equations. Furthermore, PETSc's multi-physics coupling capability (DMComposite) is used to solve the tightly coupled system of equations of the SPAC model. Numerical results are presented for multiple test problems.

Perfusion-decellularization of human ear grafts enables ECM-based scaffolds for auricular vascularized composite tissue engineering.

PubMed

Duisit, Jérôme; Amiel, Hadrien; Wüthrich, Tsering; Taddeo, Adriano; Dedriche, Adeline; Destoop, Vincent; Pardoen, Thomas; Bouzin, Caroline; Joris, Virginie; Magee, Derek; Vögelin, Esther; Harriman, David; Dessy, Chantal; Orlando, Giuseppe; Behets, Catherine; Rieben, Robert; Gianello, Pierre; Lengelé, Benoît

2018-06-01

Human ear reconstruction is recognized as the emblematic enterprise in tissue engineering. Up to now, it has failed to reach human applications requiring appropriate tissue complexity along with an accessible vascular tree. We hereby propose a new method to process human auricles in order to provide a poorly immunogenic, complex and vascularized ear graft scaffold. 12 human ears with their vascular pedicles were procured. Perfusion-decellularization was applied using a SDS/polar solvent protocol. Cell and antigen removal was examined by histology and DNA was quantified. Preservation of the extracellular matrix (ECM) was assessed by conventional and 3D-histology, proteins and cytokines quantifications. Biocompatibility was assessed by implantation in rats for up to 60 days. Adipose-derived stem cells seeding was conducted on scaffold samples and with human aortic endothelial cells whole graft seeding in a perfusion-bioreactor. Histology confirmed cell and antigen clearance. DNA reduction was 97.3%. ECM structure and composition were preserved. Implanted scaffolds were tolerated in vivo, with acceptable inflammation, remodeling, and anti-donor antibody formation. Seeding experiments demonstrated cell engraftment and viability. Vascularized and complex auricular scaffolds can be obtained from human source to provide a platform for further functional auricular tissue engineered constructs, hence providing an ideal road to the vascularized composite tissue engineering approach. The ear is emblematic in the biofabrication of tissues and organs. Current regenerative medicine strategies, with matrix from donor tissues or 3D-printed, didn't reach any application for reconstruction, because critically missing a vascular tree for perfusion and transplantation. We previously described the production of vascularized and cell-compatible scaffolds, from porcine ear grafts. In this study, we ---- applied findings directly to human auricles harvested from postmortem donors, providing a perfusable matrix that retains the ear's original complexity and hosts new viable cells after seeding. This approach unlocks the ability to achieve an auricular tissue engineering approach, associated with possible clinical translation. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Analysis of vascular endothelial dysfunction genes and related pathways in obesity through systematic bioinformatics.

PubMed

Zhang, Hui; Wang, Jing; Sun, Ling; Xu, Qiuqin; Hou, Miao; Ding, Yueyue; Huang, Jie; Chen, Ye; Cao, Lei; Zhang, Jianmin; Qian, Weiguo; Lv, Haitao

2015-01-01

Obesity has become an increasingly serious health problem and popular research topic. It is associated with many diseases, especially cardiovascular disease (CVD)-related endothelial dysfunction. This study analyzed genes related to endothelial dysfunction and obesity and then summarized their most significant signaling pathways. Genes related to vascular endothelial dysfunction and obesity were extracted from a PubMed database, and analyzed by STRING, DAVID, and Gene-Go Meta-Core software. 142 genes associated with obesity were found to play a role in endothelial dysfunction in PubMed. A significant pathway (Angiotensin system maturation in protein folding and maturation) associated with obesity and endothelial dysfunction was explored. The genes and the pathway explored may play an important role in obesity. Further studies about preventing vascular endothelial dysfunction obesity should be conducted through targeting these loci and pathways.

Engineering Pre-vascularized Scaffolds for Bone Regeneration.

PubMed

Barabaschi, Giada D G; Manoharan, Vijayan; Li, Qing; Bertassoni, Luiz E

2015-01-01

Survival of functional tissue constructs of clinically relevant size depends on the formation of an organized and uniformly distributed network of blood vessels and capillaries. The lack of such vasculature leads to spatio-temporal gradients in oxygen, nutrients and accumulation of waste products inside engineered tissue constructs resulting in negative biological events at the core of the scaffold. Unavailability of a well-defined vasculature also results in ineffective integration of scaffolds to the host vasculature upon implantation. Arguably, one of the greatest challenges in engineering clinically relevant bone substitutes, therefore, has been the development of vascularized bone scaffolds. Various approaches ranging from peptide and growth factor functionalized biomaterials to hyper-porous scaffolds have been proposed to address this problem with reasonable success. An emerging alternative to address this challenge has been the fabrication of pre-vascularized scaffolds by taking advantage of biomanufacturing techniques, such as soft- and photo-lithography or 3D bioprinting, and cell-based approaches, where functional capillaries are engineered in cell-laden scaffolds prior to implantation. These strategies seek to engineer pre-vascularized tissues in vitro, allowing for improved anastomosis with the host vasculature upon implantation, while also improving cell viability and tissue development in vitro. This book chapter provides an overview of recent methods to engineer pre-vascularized scaffolds for bone regeneration. We first review the development of functional blood capillaries in bony structures and discuss controlled delivery of growth factors, co-culture systems, and on-chip studies to engineer vascularized cell-laden biomaterials. Lastly, we review recent studies using microfabrication techniques and 3D printing to engineer pre-vascularized scaffolds for bone tissue engineering.

Blood-pool SPECT in addition to bone SPECT in the viability assessment in mandibular reconstruction.

PubMed

Aydogan, F; Akbay, E; Cevik, C; Kalender, E

2014-01-01

The assessment of the postoperative viability of vascularized and non-vascularized grafts used in the reconstruction of mandibular defects due to trauma and surgical reasons is a major problem in maxillofacial surgery. In the present study, we evaluated the feasibility and image quality of blood-pool SPECT, which is used for the first time in the literature here in the assessment of mandibular reconstruction, in addition to non-invasive bone scintigraphy and bone SPECT. We also evaluated whether it would be useful in clinical prediction. Micro-vascularized and non-vascularized bone grafts were used in 12 Syrian men with maxillofacial trauma. Between days 5-7 after surgery, three-phase bone scintigraphy, blood-pool SPECT and delayed bone SPECT scans were performed. After month 6, the patients were assessed by control CT scans. Of the non-vascularized grafts, one graft was reported as non-viable at week one. At month 6, graft resorption was demonstrated on the CT images. The remaining non-vascularized grafts and all of the micro-vascularized grafts were considered to be viable according to delayed bone SPECT and blood-pool SPECT images. However, only the anterior and posterior ends could be clearly assessed on delayed SPECT images, while blood-pool SPECT images allowed the clear assessment of the entire graft. The combined use of blood-pool and delayed SPECT scans could allow for better assessment of graft viability in the early period, and can provide more detailed information to clinicians about prognosis in the follow-up of patients undergoing mandibular graft reconstruction.

Travellers accessing addiction services in Ireland (2007 to 2010): analysis of routine surveillance data.

PubMed

Carew, Anne Marie; Cafferty, Siobhán; Long, Jean; Bellerose, Delphine; Lyons, Suzi

2013-01-01

By accessing addiction treatment services recorded in routine national drug treatment data, the characteristics of Irish Travellers were analyzed to understand their needs and develop policies to tackle issues faced by this community. The number of Traveller cases accessing services increased by 163% between 2007 and 2010. Alcohol and opiates were the most common problem substances reported. Traveller women reported high rates of problem opiate use and risky injecting behaviors, contrary to the perception that problem substance use is a predominantly male issue. This presents a challenge to services to provide targeted, effective services to Travellers with problem substance use.

Detection of pulmonary nodules in CT images based on fuzzy integrated active contour model and hybrid parametric mixture model.

PubMed

Li, Bin; Chen, Kan; Tian, Lianfang; Yeboah, Yao; Ou, Shanxing

2013-01-01

The segmentation and detection of various types of nodules in a Computer-aided detection (CAD) system present various challenges, especially when (1) the nodule is connected to a vessel and they have very similar intensities; (2) the nodule with ground-glass opacity (GGO) characteristic possesses typical weak edges and intensity inhomogeneity, and hence it is difficult to define the boundaries. Traditional segmentation methods may cause problems of boundary leakage and "weak" local minima. This paper deals with the above mentioned problems. An improved detection method which combines a fuzzy integrated active contour model (FIACM)-based segmentation method, a segmentation refinement method based on Parametric Mixture Model (PMM) of juxta-vascular nodules, and a knowledge-based C-SVM (Cost-sensitive Support Vector Machines) classifier, is proposed for detecting various types of pulmonary nodules in computerized tomography (CT) images. Our approach has several novel aspects: (1) In the proposed FIACM model, edge and local region information is incorporated. The fuzzy energy is used as the motivation power for the evolution of the active contour. (2) A hybrid PMM Model of juxta-vascular nodules combining appearance and geometric information is constructed for segmentation refinement of juxta-vascular nodules. Experimental results of detection for pulmonary nodules show desirable performances of the proposed method.

Thrombophilia and Pregnancy Complications

PubMed Central

Simcox, Louise E.; Ormesher, Laura; Tower, Clare; Greer, Ian A.

2015-01-01

There is a paucity of strong evidence associated with adverse pregnancy outcomes and thrombophilia in pregnancy. These problems include both early (recurrent miscarriage) and late placental vascular-mediated problems (fetal loss, pre-eclampsia, placental abruption and intra-uterine growth restriction). Due to poor quality case-control and cohort study designs, there is often an increase in the relative risk of these complications associated with thrombophilia, particularly recurrent early pregnancy loss, late fetal loss and pre-eclampsia, but the absolute risk remains very small. It appears that low-molecular weight heparin has other benefits on the placental vascular system besides its anticoagulant properties. Its use is in the context of antiphospholipid syndrome and recurrent pregnancy loss and also in women with implantation failure to improve live birth rates. There is currently no role for low-molecular weight heparin to prevent late placental-mediated complications in patients with inherited thrombophilia and this may be due to small patient numbers in the studies involved in summarising the evidence. There is potential for low-molecular weight heparin to improve pregnancy outcomes in women with prior severe vascular complications of pregnancy such as early-onset intra-uterine growth restriction and pre-eclampsia but further high quality randomised controlled trials are required to answer this question. PMID:26633369

Active iris vascular tufts bleeding successfully treated with argon laser photocoagulation.

PubMed

Sarmad, Ambreen; Alfaqawi, Fadi; Chakrabarti, Monali; Mitra, Arijit; Mushtaq, Bushra

2018-03-01

Iris vascular tufts (IVT) are rare biomicroscopic capillary outgrowths from the pupillary margins. Patients are usually asymptomatic until presenting with blurred vision due to spontaneous hyphema or with raised intraocular pressure. A 61-year-old woman presented to eye casualty with left eye (LE) blurred vision and discomfort for 1 day. Her external ocular examination was unremarkable and visual acuity was 6/6 in the right eye (RE) and 6/9 in the LE. Biomicroscopic examination revealed a 2-mm hyphema in her LE and bilateral multiple small IVT and active bleeding from IVT at the pupillary margin of the LE at the 5 o'clock position. Diagnosis of LE active bleeding from IVT was made and she underwent argon laser photocoagulation directed at the source of bleeding. The bleeding stopped immediately after the second burn. She was followed up for 3 months; her visual acuity was 6/5 and 6/6 in the RE and LE, respectively, with no further problems. Iris vascular tufts are benign and recurrent hemorrhages are unlikely. Therefore, definitive argon laser photocoagulation or surgical treatment are reserved to arrest further episodes of hyphema. Our case demonstrates the effective use of argon laser photocoagulation to completely arrest active bleeding from IVT and excellent recovery of hyphema with no further problems for 5 years.

COX-2 – A Novel Target for Reducing Tumor Angiogenesis and Metastasis | Center for Cancer Research

Cancer.gov

Angiogenesis is essential for tumor growth and metastasis, by supplying a steady stream of nutrients, removing waste, and providing tumor cells access to other sites in the body. The vascular endothelial growth factor (VEGF) and its receptors (VEGFRs) play a key role in tumor-mediated angiogenesis, and this pathway is the target of monoclonal antibodies and tyrosine kinase

Global Genome Biodiversity Network: saving a blueprint of the Tree of Life - a botanical perspective.

PubMed

Seberg, O; Droege, G; Barker, K; Coddington, J A; Funk, V; Gostel, M; Petersen, G; Smith, P P

2016-09-01

Genomic research depends upon access to DNA or tissue collected and preserved according to high-quality standards. At present, the collections in most natural history museums do not sufficiently address these standards, making them often hard or impossible to use for whole-genome sequencing or transcriptomics. In response to these challenges, natural history museums, herbaria, botanical gardens and other stakeholders have started to build high-quality biodiversity biobanks. Unfortunately, information about these collections remains fragmented, scattered and largely inaccessible. Without a central registry or even an overview of relevant institutions, it is difficult and time-consuming to locate the needed samples. The Global Genome Biodiversity Network (GGBN) was created to fill this vacuum by establishing a one-stop access point for locating samples meeting quality standards for genome-scale applications, while complying with national and international legislations and conventions. Increased accessibility to genomic samples will further genomic research and development, conserve genetic resources, help train the next generation of genome researchers and raise the visibility of biodiversity collections. Additionally, the availability of a data-sharing platform will facilitate identification of gaps in the collections, thereby empowering targeted sampling efforts, increasing the breadth and depth of preservation of genetic diversity. The GGBN is rapidly growing and currently has 41 members. The GGBN covers all branches of the Tree of Life, except humans, but here the focus is on a pilot project with emphasis on 'harvesting' the Tree of Life for vascular plant taxa to enable genome-level studies. While current efforts are centred on getting the existing samples of all GGBN members online, a pilot project, GGI-Gardens, has been launched as proof of concept. Over the next 6 years GGI-Gardens aims to add to the GGBN high-quality genetic material from at least one species from each of the approx. 460 vascular plant families and one species from half of the approx. 15 000 vascular plant genera. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company.

Hospitalization in daily home hemodialysis and matched thrice-weekly in-center hemodialysis patients.

PubMed

Weinhandl, Eric D; Nieman, Kimberly M; Gilbertson, David T; Collins, Allan J

2015-01-01

Cardiovascular disease is a common cause of hospitalization in dialysis patients. Daily hemodialysis improves some parameters of cardiovascular function, but whether it associates with lower hospitalization risk is unclear. Observational cohort study using US Renal Data System data. Medicare-enrolled daily (5 or 6 sessions weekly) home hemodialysis (HHD) patients initiating NxStage System One use from January 1, 2006, through December 31, 2009, and contemporary thrice-weekly in-center hemodialysis patients, matched 5 to 1. Daily HHD or thrice-weekly in-center hemodialysis. All-cause and cause-specific hospital admissions, hospital readmissions, and hospital days assessed from Medicare Part A claims. For 3,480 daily HHD and 17,400 thrice-weekly in-center hemodialysis patients in intention-to-treat analysis, the HR of all-cause admission for daily HHD versus in-center hemodialysis was 1.01 (95%CI, 0.98-1.03). Cause-specific admission HRs were 0.89 (95%CI, 0.86-0.93) for cardiovascular disease, 1.18 (95%CI, 1.13-1.23) for infection, 1.01 (95%CI, 0.93-1.09) for vascular access dysfunction, and 1.02 (95%CI, 0.99-1.06) for other morbidity. Regarding cardiovascular disease, first admission and readmission HRs for daily HHD versus in-center hemodialysis were 0.91 and 0.87, respectively. Regarding infection, first admission and readmission HRs were 1.35 and 1.03, respectively. Protective associations of daily HHD with heart failure and hypertensive disease were most pronounced, as were adverse associations of daily HHD with bacteremia/sepsis, cardiac infection, osteomyelitis, and vascular access infection. Results may be confounded by unmeasured factors, including vascular access type; information about dialysis frequency, duration, and dose was lacking; causes of admission may be misclassified; results may not apply to patients without Medicare coverage. All-cause hospitalization risk was similar in daily HHD and thrice-weekly in-center hemodialysis patients. However, risk of cardiovascular-related admission was lower with daily HHD, and risk of infection-related admission was higher. More attention should be afforded to infection in HHD patients. Copyright © 2014 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Main trends in experimental morphological research in angiology and outlook for its development

NASA Technical Reports Server (NTRS)

Dzhavakhishvili, N. A.; Melman, Y. P.

1980-01-01

The main prospective trends in the problem of collateral circulation and new trends in experimental angiology with respect to the effect of gravitational forces, hypodynamia and hypokinesia on the vascular bed are discussed.

ARSENIC - SUSCEPTIBILITY & IN UTERO EFFECTS

EPA Science Inventory

Exposure to inorganic arsenic remains a serious public health problem at many locations worldwide. If has often been noted that prevalences of signs and symptoms of chronic arsenic poisoning differ among various populations. For example, skin lesions or peripheral vascular dis...

[Lack of access to information on oral health problems among adults: an approach based on the theoretical model for literacy in health].

PubMed

Roberto, Luana Leal; Noronha, Daniele Durães; Souza, Taiane Oliveira; Miranda, Ellen Janayne Primo; Martins, Andréa Maria Eleutério de Barros Lima; Paula, Alfredo Maurício Batista De; Ferreira, Efigênia Ferreira E; Haikal, Desirée Sant'ana

2018-03-01

This study sought to investigate factors associated with the lack of access to information on oral health among adults. It is a cross-sectional study, carried out among 831 adults (35-44 years of age). The dependent variable was access to information on how to avoid oral problems, and the independent variables were gathered into subgroups according to the theoretical model for literacy in health. Binary logistic regression was carried out, and results were corrected by the design effect. It was observed that 37.5% had no access to information about dental problems. The lack of access was higher among adults who had lower per capita income, were dissatisfied with the dental services provided, did not use dental floss, had unsatisfactory physical control of the quality of life, and self-perceived their oral health as fair/poor/very poor. The likelihood of not having access to information about dental problems among those dissatisfied with the dental services used was 3.28 times higher than for those satisfied with the dental services used. Thus, decreased access to information was related to unfavorable conditions among adults. Health services should ensure appropriate information to their users in order to increase health literacy levels and improve satisfaction and equity.

Video game access, parental rules, and problem behavior: a study of boys with autism spectrum disorder.

PubMed

Engelhardt, Christopher R; Mazurek, Micah O

2014-07-01

Environmental correlates of problem behavior among individuals with autism spectrum disorder remain relatively understudied. The current study examined the contribution of in-room (i.e. bedroom) access to a video game console as one potential correlate of problem behavior among a sample of 169 boys with autism spectrum disorder (ranging from 8 to 18 years of age). Parents of these children reported on (1) whether they had specific rules regulating their child's video game use, (2) whether their child had in-room access to a variety of screen-based media devices (television, computer, and video game console), and (3) their child's oppositional behaviors. Multivariate regression models showed that in-room access to a video game console predicted oppositional behavior while controlling for in-room access to other media devices (computer and television) and relevant variables (e.g. average number of video game hours played per day). Additionally, the association between in-room access to a video game console and oppositional behavior was particularly large when parents reported no rules on their child's video game use. The current findings indicate that both access and parental rules regarding video games warrant future experimental and longitudinal research as they relate to problem behavior in boys with autism spectrum disorder. © The Author(s) 2013.

Dual implantation of a radio-telemeter and vascular access port allows repeated hemodynamic and pharmacological measures in conscious lean and obese rats.

PubMed

Bussey, C T; Leeuw, A E de; Cook, R F; Ashley, Z; Schofield, J; Lamberts, R R

2014-07-01

Expansion of physiological knowledge increasingly requires examination of processes in the normal, conscious state. The current study describes a novel approach combining surgical implantation of radio-telemeters with vascular access ports (VAPs) to allow repeated hemodynamic and pharmacological measures in conscious rats. Dual implantation was conducted on 16-week-old male lean and obese Zucker rats. Continued viability one month after surgery was observed in 67% of lean and 44% of obese animals, giving an overall 54% completion rate. Over the five-week measurement period, reliable and reproducible basal mean arterial pressure and heart rate measures were observed. VAP patency and receptor-independent vascular reactivity were confirmed by consistent hemodynamic responses to sodium nitroprusside (6.25 µg/kg). Acutely, minimal hemodynamic responses to repeated bolus administration of 0.2 mL saline indicated no significant effect of increased blood volume or administration stress, making repeated acute measures viable. Similarly, repeated administration of the β-adrenoceptor agonist dobutamine (30 µg/kg) at 10 min intervals resulted in reproducible hemodynamic changes in both lean and obese animals. Therefore, our study demonstrates that this new approach is viable for the acute and chronic assessment of hemodynamic and pharmacological responses in both lean and obese conscious rats. This technique reduces the demand for animal numbers and allows hemodynamic measures with minimal disruption to animals' welfare, while providing reliable and reproducible results over several weeks. In conclusion, dual implantation of a radio-telemeter and VAP introduces a valuable technique for undertaking comprehensive studies involving repeated pharmacological tests in conscious animals to address important physiological questions. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Analysis of intraoperative difficulties and management of operative complications in revision anterior exposure of the lumbar spine: a report of 25 consecutive cases.

PubMed

Flouzat-Lachaniette, Charles-Henri; Delblond, William; Poignard, Alexandre; Allain, Jérôme

2013-04-01

After a first anterior approach to the lumbar spine, formation of adhesions of soft tissues to the spine increases the surgical difficulties and potential for iatrogenic injury during the revision exposure. The objective of this study was to identify the intraoperative difficulties and postoperative complications associated with revision anterior lumbar spine procedures in a single institution. This is a retrospective review of 25 consecutive anterior revision lumbar surgeries in 22 patients (7 men and 15 women) operated on between 1998 and 2011. Patients with trauma or malignancies were excluded. The mean age of the patients at the time of revision surgery was 56 years (range 20-80 years). The complications were analyzed depending on the operative level and the time between the index surgery and the revision. Six major complications (five intraoperatively and one postoperatively) occurred in five patients (20 %): three vein lacerations (12 %) and two ureteral injuries (8 %), despite the presence of a double-J ureteral stent. The three vein damages were repaired or ligated by a vascular surgeon. One of the two ureteral injuries led to a secondary nephrectomy after end-to-end anastomosis failure; the other necessitated secondary laparotomy for small bowel obstruction. Anterior revision of the lumbar spine is technically challenging and is associated with a high rate of vascular or urologic complications. Therefore, the potential complications of the procedure must be weighted against its benefits. When iterative anterior lumbar approach is mandatory, exposure should be performed by an access surgeon in specialized centers that have ready access to vascular and urologic surgeons.

Vascular access clinic results before and after implementing a multidisciplinary approach adding routine Doppler ultrasound.

PubMed

Aragoncillo Sauco, Inés; Ligero Ramos, José Manuel; Vega Martínez, Almudena; Morales Muñoz, Ángel Luis; Abad Estébanez, Soraya; Macías Carmona, Nicolás; Ruiz Chiriboga, Diego; García Pajares, Rosario; Cervera Bravo, Teresa; López-Gómez, Juan Manuel; Manzano Grossi, Soledad; Menéndez Sánchez, Elena; Río Gomez, Javier; García Prieto, Ana María; Linares Grávalos, Tania; Garcia Boyano, Fernando; Reparaz Asensio, Luis Manuel; Albalate Ramón, Marta; de Sequera Ortiz, Patricia; Gil Casares, Beatriz; Ampuero Mencía, Jara; Castellano, Sandra; Martín Pérez, Belén; Conty, José Luís Martín; Santos Garcia, Alba; Luño Fernandez, José

2018-06-11

A multidisciplinary approach and Doppler ultrasound (DU) assessment for the creation and maintenance of arteriovenous fistulas (AVF) for haemodialysis can improve prevalence and patency. The aim of this study was to analyse the impact of a new multidisciplinary vascular access (VA) clinic with routine DU. We analysed the VA clinic results from 2014 and 2015, before and after the implementation of a multidisciplinary team protocol (vascular surgeon/nephrologist) with routine DU in preoperative mapping and prevalent AVF. We analysed 345 and 364 patients from 2014 and 2015 respectively. The number of surgical interventions was similar in both periods (p=.289), with a trend towards an increase in preventive surgical repair of AVF in 2015 (17 vs. 29, p=.098). 155 vs. 169 new AVF were performed in 2014 and 2015, with a significantly lower primary failure rate in 2015 (26.4 vs. 15.3%, p=.015), and a non-significant increase in radiocephalic AVF, 25.8 vs. 33.2% (n=40 vs. 56), p=.159. The concordance between the indication at the clinic and the surgery performed also increased (81.3 vs. 93.5%, p=.001). Throughout 2015 fewer complementary imaging test were requested from the clinic (78 vs. 35, p <.001), with a corresponding reduction in costs (€87,716 vs. €59,445). Multidisciplinary approach with routine DU can improve VA results, with a decrease in primary failure rate, higher likelihood of radiocephalic AVF, better management of dis-functioning AVF and lower radiological test costs. Copyright © 2018 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

Current Trends in Heparin Use During Arterial Vascular Interventional Radiology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Durran, Alexandra C., E-mail: durranjobs@hotmail.com; Watts, Christopher, E-mail: Christopher.watts@salisbury.nhs.uk

2012-12-15

Purpose: This study was designed to assess the current use of heparinized saline and bolus doses of heparin in non-neurological interventional radiology and to determine whether consensus could be reached to produce guidance for heparin use during arterial vascular intervention. Methods: An interactive electronic questionnaire was distributed to members of the British Society of Interventional Radiology regarding their current practice in the use, dosage, and timing of heparin boluses and heparinized flushing solutions.ResultsA total of 108 completed questionnaires were received. More than 80% of respondents used heparinized saline with varying concentrations; the most prevalent was 1,000 IU/l (international units ofmore » heparin per liter) and 5,000 IU/l. Fifty-one percent of interventionalists use 3,000 IU as their standard bolus dose; however, the respondents were split regarding the timing of bolus dose with {approx}60% administering it after arterial access is obtained and 40% after crossing the lesion. There was no consensus on altering dose according to body weight, and only 4% monitored clotting parameters. Conclusions: There seems to be some coherence among practicing interventionalists regarding heparin administration. We hypothesize that heparinized saline should be used at a recognized standard concentration of 1,000 IU/l as a flushing concentration in all arterial vascular interventions and that 3,000 IU bolus is considered the standard dose for straightforward therapeutic procedures and 5000 IU for complex, crural, and endovascular aneurysm repair work. The bolus should be given after arterial access is obtained to allow time for optimal anticoagulation to be achieved by the time of active intervention and stenting. Further research into clotting abnormalities following such interventional procedures would be an interesting quantifiable follow-up to this initial survey of opinions and practice.« less

[Quantification and monitoring of vascular resistance in the lower limbs by the Doppler method (animal model)

NASA Technical Reports Server (NTRS)

Arbeille, P.; Berson, M.; Blondeau, B.; Durand, A.; Bodard, S.; Locatelli, A.; Fox, G. E. (Principal Investigator)

1995-01-01

The object of this study was to define and validate a non-invasive method of evaluation and monitoring of vascular resistances in the leg. Blood flow velocity was measured by Doppler ultrasound in an animal model (ewe) with similar blood flow characteristics in the lower limb as man and allowing access to the required invasive measurements for validation of the method (pressure and flow). Vascular resistances distal to the measuring point (femoral, for example) were assessed using the resistance index R = D/S, S being the peak systolic deflection and D that of diastolic reflux of the Doppler spectral analysis of flow in the femoral artery. The values and variations of this resistance index were compared with the vascular resistances calculated from measurements of pressure and flow at the point of Doppler sampling and expressed in mmHg/ml/min. Femoral flow was measured by Doppler ultrasound (Doppler-echo), and mean pressure by an arterial catheter introduced into the abdominal aorta. Compression of the lower limb veins induced a venous return resulting in a reduction of cardiac output and femoral flow. During compression, femoral flow decreased by an average of 29% (p < 0.001) although mean pressure and heart rate did not change significantly. The femoral resistance index (Rf) increased by an average of 37.5% (p < 0.01) and vascular resistances increased by 45.9% (p < 0.01). Injection of 1 mg adrenaline induced peripheral vasoconstriction with an increase in blood pressure and a decrease in heart rate and femoral flow.(ABSTRACT TRUNCATED AT 250 WORDS).

Prevention and management of vascular complications in middle ear and cochlear implant surgery.

PubMed

Di Lella, Filippo; Falcioni, Maurizio; Piccinini, Silvia; Iaccarino, Ilaria; Bacciu, Andrea; Pasanisi, Enrico; Cerasti, Davide; Vincenti, Vincenzo

2017-11-01

The objective of this study is to illustrate prevention strategies and management of vascular complications from the jugular bulb (JB) and internal carotid artery (ICA) during middle ear surgery or cochlear implantation. The study design is retrospective case series. The setting is tertiary referral university hospital. Patients were included if presented pre- or intraoperative evidence of high-risk anatomical anomalies of ICA or JB during middle ear or cochlear implant surgery, intraoperative vascular injury, or revision surgery after the previous iatrogenic vascular lesions. The main outcome measures are surgical outcomes and complications rate. Ten subjects were identified: three underwent cochlear implant surgery and seven underwent middle ear surgery. Among the cochlear implant patients, two presented with anomalies of the JB impeding access to the cochlear lumen and one underwent revision surgery for incorrect positioning of the array in the carotid canal. Subtotal petrosectomy was performed in all cases. Anomalies of the JB were preoperatively identified in two patients with attic and external auditory canal cholesteatoma, respectively. In a patient, a high and dehiscent JB was found during myringoplasty, while another underwent revision surgery after iatrogenic injury of the JB. A dehiscent ICA complicated middle ear effusion in one case, while in another case, a carotid aneurysm determined a cholesterol granuloma. Rupture of a pseudoaneurysm of the ICA occurred in a child during second-stage surgery and required permanent balloon occlusion without neurological complications. Knowledge of normal anatomy and its variants and preoperative imaging are the basis for prevention of vascular complications during middle ear or cochlear implant surgery.

Antenatal Hypoxia and Pulmonary Vascular Function and Remodeling

PubMed Central

Papamatheakis, Demosthenes G.; Blood, Arlin B.; Kim, Joon H.; Wilson, Sean M.

2015-01-01

This review provides evidence that antenatal hypoxia, which represents a significant and worldwide problem, causes prenatal programming of the lung. A general overview of lung development is provided along with some background regarding transcriptional and signaling systems of the lung. The review illustrates that antenatal hypoxic stress can induce a continuum of responses depending on the species examined. Fetuses and newborns of certain species and specific human populations are well acclimated to antenatal hypoxia. However, antenatal hypoxia causes pulmonary vascular disease in fetuses and newborns of most mammalian species and humans. Disease can range from mild pulmonary hypertension, to severe vascular remodeling and dangerous elevations in pressure. The timing, length, and magnitude of the intrauterine hypoxic stress are important to disease development, however there is also a genetic-environmental relationship that is not yet completely understood. Determining the origins of pulmonary vascular remodeling and pulmonary hypertension and their associated effects is a challenging task, but is necessary in order to develop targeted therapies for pulmonary hypertension in the newborn due to antenatal hypoxia that can both treat the symptoms and curtail or reverse disease progression. PMID:24063380

Improvement of vascular function by magnetic nanoparticle-assisted circumferential gene transfer into the native endothelium.

PubMed

Vosen, Sarah; Rieck, Sarah; Heidsieck, Alexandra; Mykhaylyk, Olga; Zimmermann, Katrin; Plank, Christian; Gleich, Bernhard; Pfeifer, Alexander; Fleischmann, Bernd K; Wenzel, Daniela

2016-11-10

Gene therapy is a promising approach for chronic disorders that require continuous treatment such as cardiovascular disease. Overexpression of vasoprotective genes has generated encouraging results in animal models, but not in clinical trials. One major problem in humans is the delivery of sufficient amounts of genetic vectors to the endothelium which is impeded by blood flow, whereas prolonged stop-flow conditions impose the risk of ischemia. In the current study we have therefore developed a strategy for the efficient circumferential lentiviral gene transfer in the native endothelium under constant flow conditions. For that purpose we perfused vessels that were exposed to specially designed magnetic fields with complexes of lentivirus and magnetic nanoparticles thereby enabling overexpression of therapeutic genes such as endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor (VEGF). This treatment enhanced NO and VEGF production in the transduced endothelium and resulted in a reduction of vascular tone and increased angiogenesis. Thus, the combination of MNPs with magnetic fields is an innovative strategy for site-specific and efficient vascular gene therapy. Copyright © 2016 Elsevier B.V. All rights reserved.

[The place of vascular surgery in the treatment of cancer patients].

PubMed

Gaibov, A D; Zikiriakhodzhaev, D Z; Sultanov, D D; Karimova, N R

2004-01-01

The aim of the present work was to analyze the reported data related to the diagnostic potential of delineating the degree of blood vessel involvement into the tumorous process in patients with cancer diseases of varying sites and to the choice of the method for surgical treatment of this group patients. Half century ago an idea was advanced of the necessity of performing vascular operations during evacuation of tumors of certain sites. Based on the analysis of numerous publications the authors have established that the lowering of the lethality and improvement of the quality of life in patients with oncopathology are determined in many respects by one-stage operations performed on the great vessels, allowing to broaden the indications for tumor resection. The review elucidates the current achievements of vascular surgery linked with oncology, mirrors the historical viewpoint of the given problem, describes an experience of different authors gained with the use of the modern noninvasive research modalities in the diagnosis of vascular involvement into tumorous growth. As dependent on the site, tumor morphology and hemodynamic significance of the affected vascular segment, the indications have been worked out for different types of operations on the arteries and veins. The authors emphasize the potential and safety of great vessel ligation after radical resection of tumors of certain sites.

Teleconsultation in vascular surgery: a 13 year single centre experience.

PubMed

Schmidt, Christian A P; Schmidt-Weitmann, Sabine H; Lachat, Mario L; Brockes, Christiane M

2014-01-01

The University Hospital of Zurich has provided an email-based medical consultation service for the general public since 1999. We examined the enquiries in a 13-year period to identify those related to vascular surgery (based on 22 ICD-10 codes specific for vascular surgery). There were 40,062 questions, of which 643 (2%) were selected by ICD-10 codes. After exclusion of diagnoses not relevant to vascular surgery, 139 questions remained, i.e. an average rate of about one per month. The mean age of the users was 43 years (range 19-88). Most users (61%) were women. The majority of users asked questions about their own health problems (79%) with varicose veins and spider veins accounting for 63% of all questions. Arterial diseases accounted for 30%. The patient's intention in contacting the service was to obtain advice on treatment options (37%), information about a diagnosis or symptoms (27%), or a second opinion (15%). The online service responded with detailed information and advice (87%) and suggested a referral to the family doctor or a specialist in 75%. Most patients (82%) rated the service overall as good or very good. It appears likely that telemedicine and in particular email teleconsultations will increase in vascular surgery in the future.

Effect of Caffeic Acid Phenethyl Ester on Vascular Damage Caused by Consumption of High Fructose Corn Syrup in Rats

PubMed Central

Gun, Aburrahman; Bilgic, Sedat; Kocaman, Nevin; Ozan, Gonca

2016-01-01

Fructose corn syrup is cheap sweetener and prolongs the shelf life of products, but fructose intake causes hyperinsulinemia, hypertriglyceridemia, and hypertension. All of them are referred to as metabolic syndrome and they are risk factors for cardiovascular diseases. Hence, the harmful effects of increased fructose intake on health and their prevention should take greater consideration. Caffeic Acid Phenethyl Ester (CAPE) has beneficial effects on metabolic syndrome and vascular function which is important in the prevention of cardiovascular disease. However, there are no known studies about the effect of CAPE on fructose-induced vascular dysfunction. In this study, we examined the effect of CAPE on vascular dysfunction due to high fructose corn syrup (HFCS). HFCS (6 weeks, 30% fed with drinking water) caused vascular dysfunction, but treatment with CAPE (50 micromol/kg i.p. for the last two weeks) effectively restored this problem. Additionally, hypertension in HFCS-fed rats was also decreased in CAPE supplemented rats. CAPE supplements lowered HFCS consumption-induced raise in blood glucose, homocysteine, and cholesterol levels. The aorta tissue endothelial nitric oxide synthase (eNOS) production was decreased in rats given HFCS and in contrast CAPE supplementation efficiently increased its production. The presented results showed that HFCS-induced cardiovascular abnormalities could be prevented by CAPE treatment. PMID:27042260

Effect of Caffeic Acid Phenethyl Ester on Vascular Damage Caused by Consumption of High Fructose Corn Syrup in Rats.

PubMed

Gun, Aburrahman; Ozer, Mehmet Kaya; Bilgic, Sedat; Kocaman, Nevin; Ozan, Gonca

2016-01-01

Fructose corn syrup is cheap sweetener and prolongs the shelf life of products, but fructose intake causes hyperinsulinemia, hypertriglyceridemia, and hypertension. All of them are referred to as metabolic syndrome and they are risk factors for cardiovascular diseases. Hence, the harmful effects of increased fructose intake on health and their prevention should take greater consideration. Caffeic Acid Phenethyl Ester (CAPE) has beneficial effects on metabolic syndrome and vascular function which is important in the prevention of cardiovascular disease. However, there are no known studies about the effect of CAPE on fructose-induced vascular dysfunction. In this study, we examined the effect of CAPE on vascular dysfunction due to high fructose corn syrup (HFCS). HFCS (6 weeks, 30% fed with drinking water) caused vascular dysfunction, but treatment with CAPE (50 micromol/kg i.p. for the last two weeks) effectively restored this problem. Additionally, hypertension in HFCS-fed rats was also decreased in CAPE supplemented rats. CAPE supplements lowered HFCS consumption-induced raise in blood glucose, homocysteine, and cholesterol levels. The aorta tissue endothelial nitric oxide synthase (eNOS) production was decreased in rats given HFCS and in contrast CAPE supplementation efficiently increased its production. The presented results showed that HFCS-induced cardiovascular abnormalities could be prevented by CAPE treatment.

Vascular diseases of the liver. Clinical Guidelines from the Catalan Society of Digestology and the Spanish Association for the Study of the Liver.

PubMed

Martín-Llahí, Marta; Albillos, Agustín; Bañares, Rafael; Berzigotti, Annalisa; García-Criado, M Ángeles; Genescà, Joan; Hernández-Gea, Virginia; Llop-Herrera, Elba; Masnou-Ridaura, Helena; Mateo, José; Navascués, Carmen A; Puente, Ángela; Romero-Gutiérrez, Marta; Simón-Talero, Macarena; Téllez, Luis; Turon, Fanny; Villanueva, Cándido; Zarrabeitia, Roberto; García-Pagán, Juan Carlos

2017-10-01

Despite their relatively low prevalence, vascular diseases of the liver represent a significant health problem in the field of liver disease. A common characteristic shared by many such diseases is their propensity to cause portal hypertension together with increased morbidity and mortality. These diseases are often diagnosed in young patients and their delayed diagnosis and/or inappropriate treatment can greatly reduce life expectancy. This article reviews the current body of evidence concerning Budd-Chiari syndrome, non-cirrhotic portal vein thrombosis, idiopathic portal hypertension, sinusoidal obstruction syndrome, hepatic vascular malformations in hereditary haemorrhagic telangiectasia, cirrhotic portal vein thrombosis and other rarer vascular diseases including arterioportal fistulas. It also includes a section on the diagnostic imaging of vascular diseases of the liver and their treatment from a haematological standpoint (study of thrombotic diathesis and anticoagulation therapy). All recommendations are based on published studies extracted from PubMed. The quality of evidence and strength of recommendations were rated in accordance with the GRADE system (Grading of Recommendations, Assessment Development and Evaluation). In the absence of sufficient evidence, recommendations were based on the opinion of the committee that produced the guide. Copyright © 2017 Elsevier España, S.L.U., AEEH y AEG. All rights reserved.

[Indocyanine green infrared fluorescence angiography and vascular cast--preparation in experimental choroidal circulatory disturbance].

PubMed

Matsunaga, H; Andoh, A; Matsubara, T; Fukushima, I; Takahashi, K; Ohkuma, H; Uyama, M

1996-03-01

We performed experiments in 20 monkey eyes in order to clarify basic problems about interpretation of indocyanine green fluorescence angiography (ICG angiography). We severed the temporal group of posterior ciliary arteries to produce choroidal circulatory disturbance. ICG angiography was performed immediately, and 2 days, 4 days, and 2 weeks later. Following each ICG angiography, the eye was studied by plastic vascular cast technique with scanning electron microscopy. Immediately after occlusion, ICG angiography showed filling defect in the temporal choroidal hemisphere during the early phase. In the later phase, this area was gradually filled by the dye from choroidal arteries in the nasal hemisphere and the anterior ciliary arteries. Vascular cast preparations showed filling defect in the temporal choroidal hemisphere, corresponding with the early ICG angiogaphic findings. Both filling delay in ICG angiography and filling defect in vascular casts improved daily after occlusion. Two weeks after occlusion, The area of choroidal infarct temporal to the macula turned into chorioretinal atrophy. This area showed hypofluorescence in the early-phase ICG angiography and filling defect of the choriocapillaris in plastic casts. The early-phase ICG angiographic findings thus corresponded well with observations of vascular casts. We conclude that ICG angiography correctly reflects the actual circulatory disturbances in the choroid.

Doppler ultrasonography in living donor liver transplantation recipients: Intra- and post-operative vascular complications

PubMed Central

Abdelaziz, Omar; Attia, Hussein

2016-01-01

Living-donor liver transplantation has provided a solution to the severe lack of cadaver grafts for the replacement of liver afflicted with end-stage cirrhosis, fulminant disease, or inborn errors of metabolism. Vascular complications remain the most serious complications and a common cause for graft failure after hepatic transplantation. Doppler ultrasound remains the primary radiological imaging modality for the diagnosis of such complications. This article presents a brief review of intra- and post-operative living donor liver transplantation anatomy and a synopsis of the role of ultrasonography and color Doppler in evaluating the graft vascular haemodynamics both during surgery and post-operatively in accurately defining the early vascular complications. Intra-operative ultrasonography of the liver graft provides the surgeon with useful real-time diagnostic and staging information that may result in an alteration in the planned surgical approach and corrections of surgical complications during the procedure of vascular anastomoses. The relevant intra-operative anatomy and the spectrum of normal and abnormal findings are described. Ultrasonography and color Doppler also provides the clinicians and surgeons early post-operative potential developmental complications that may occur during hospital stay. Early detection and thus early problem solving can make the difference between graft survival and failure. PMID:27468207

The effects of preference assessment type on problem behavior.

PubMed

Tung, Sara Beth; Donaldson, Jeanne M; Kahng, SungWoo

2017-10-01

Individuals with intellectual and developmental disabilities who engage in problem behavior maintained by access to tangibles may exhibit more problem behavior during certain preference assessments. We compared three common preference assessments to determine which resulted in fewer problem behaviors. The paired stimulus and multiple-stimulus without replacement assessments produced higher rates of problem behavior than the free operant (FO) assessment, suggesting that the FO assessment may be the most appropriate assessment for individuals who engage in problem behavior maintained by access to tangibles. © 2017 Society for the Experimental Analysis of Behavior.

Cognitive access to numbers: the philosophical significance of empirical findings about basic number abilities.

PubMed

Giaquinto, Marcus

2017-02-19

How can we acquire a grasp of cardinal numbers, even the first very small positive cardinal numbers, given that they are abstract mathematical entities? That problem of cognitive access is the main focus of this paper. All the major rival views about the nature and existence of cardinal numbers face difficulties; and the view most consonant with our normal thought and talk about numbers, the view that cardinal numbers are sizes of sets, runs into the cognitive access problem. The source of the problem is the plausible assumption that cognitive access to something requires causal contact with it. It is argued that this assumption is in fact wrong, and that in this and similar cases, we should accept that a certain recognize-and-distinguish capacity is sufficient for cognitive access. We can then go on to solve the cognitive access problem, and thereby support the set-size view of cardinal numbers, by paying attention to empirical findings about basic number abilities. To this end, some selected studies of infants, pre-school children and a trained chimpanzee are briefly discussed.This article is part of a discussion meeting issue 'The origins of numerical abilities'. © 2017 The Author(s).

Outdoor motivation moderates the effects of accessibility on mobility in old age.

PubMed

Kamin, Stefan T; Beyer, Anja; Lang, Frieder R

2016-07-01

Mobility plays a major role in healthy aging and social participation. This study explored whether accessibility problems in the housing environment are negatively associated with mobility in old age and whether this association is moderated by differences in an individual's preference for spending time outside the home (outdoor motivation). This article reports the results of a research project on mobility in old age. The project included a survey study of 120 community-dwelling older adults between 59 and 92 years of age (mean = 71.7 years, SD = 7.3 years) living in the metropolitan region of Nuremberg, Germany. Objective assessments were conducted in the participants' housing environment to evaluate the magnitude of accessibility problems. Accessibility problems were negatively associated with mobility. Interaction analyses suggested a buffering effect of outdoor motivation on this association, i.e. participants who reported a preference for spending time outside the home had a higher mobility in the face of accessibility problems as compared with those who preferred staying at home. Outdoor motivation may have protective effects for older adults when accessibility problems challenge mobility. These findings contribute to improving the understanding of how and under what circumstances older adults stay mobile and active in everyday life. Considering interindividual differences in outdoor motivation may binterventions and public health programs that are aimed at enhancing mobility and social participation in old age.

Intraosseous infusions: a review for the anesthesiologist with a focus on pediatric use.

PubMed

Tobias, Joseph D; Ross, Allison Kinder

2010-02-01

Intraosseous (IO) access is used most frequently for emergency care of critically ill infants and children when IV access cannot be rapidly achieved. Despite its efficacy in such situations, applications outside of the emergency room or resuscitation scenario have been limited. Furthermore, although the technique is emphasized in the teaching of those caring for critically ill infants and children in the emergency room or critical care setting, there is limited emphasis on its potential use in the perioperative setting. When peripheral venous access cannot be achieved in the operating room, alternative means of securing vascular access such as central line placement or surgical cutdown are generally successful; however, these techniques may be time consuming. Anyone providing anesthesia care for infants and children may want to become facile with the use of IO infusions for selected indications. We present the history of IO infusions, review the anatomy of the bone marrow space, discuss the potential role of IO infusions in the perioperative period, and analyze its adverse effect profile.

Immunity at Cauliflower Hydathodes Controls Systemic Infection by Xanthomonas campestris pv campestris.

PubMed

Cerutti, Aude; Jauneau, Alain; Auriac, Marie-Christine; Lauber, Emmanuelle; Martinez, Yves; Chiarenza, Serge; Leonhardt, Nathalie; Berthomé, Richard; Noël, Laurent D

2017-06-01

Hydathodes are water pores found on leaves of a wide range of vascular plants and are the sites of guttation. We report here on the detailed anatomy of cauliflower ( Brassica oleracea ) and Arabidopsis ( Arabidopsis thaliana ) hydathodes. Hydathode surface presents pores resembling stomata giving access to large cavities. Beneath, the epithem is composed of a lacunar and highly vascularized parenchyma offering a direct connection between leaf surface and xylem vessels. Arabidopsis hydathode pores were responsive to ABA and light similar to stomata. The flg22 flagellin peptide, a well-characterized elicitor of plant basal immunity, did not induce closure of hydathode pores in contrast to stomata. Because hydathodes are natural infection routes for several pathogens, we investigated hydathode infection by the adapted vascular phytopathogenic bacterium Xanthomonas campestris pv campestris ( Xcc ), the causal agent of black rot disease of Brassicaceae. Microscopic observations of hydathodes six days postinoculation indicated a digestion of the epithem cells and a high bacterial multiplication. Postinvasive immunity was shown to limit pathogen growth in the epithem and is actively suppressed by the type III secretion system and its effector proteins. Altogether, these results give a detailed anatomic description of Brassicaceae hydathodes and highlight the efficient use of this tissue as an initial niche for subsequent vascular systemic dissemination of Xcc in distant plant tissues. © 2017 American Society of Plant Biologists. All Rights Reserved.

A Re-Engineered Software Interface and Workflow for the Open-Source SimVascular Cardiovascular Modeling Package.

PubMed

Lan, Hongzhi; Updegrove, Adam; Wilson, Nathan M; Maher, Gabriel D; Shadden, Shawn C; Marsden, Alison L

2018-02-01

Patient-specific simulation plays an important role in cardiovascular disease research, diagnosis, surgical planning and medical device design, as well as education in cardiovascular biomechanics. simvascular is an open-source software package encompassing an entire cardiovascular modeling and simulation pipeline from image segmentation, three-dimensional (3D) solid modeling, and mesh generation, to patient-specific simulation and analysis. SimVascular is widely used for cardiovascular basic science and clinical research as well as education, following increased adoption by users and development of a GATEWAY web portal to facilitate educational access. Initial efforts of the project focused on replacing commercial packages with open-source alternatives and adding increased functionality for multiscale modeling, fluid-structure interaction (FSI), and solid modeling operations. In this paper, we introduce a major SimVascular (SV) release that includes a new graphical user interface (GUI) designed to improve user experience. Additional improvements include enhanced data/project management, interactive tools to facilitate user interaction, new boundary condition (BC) functionality, plug-in mechanism to increase modularity, a new 3D segmentation tool, and new computer-aided design (CAD)-based solid modeling capabilities. Here, we focus on major changes to the software platform and outline features added in this new release. We also briefly describe our recent experiences using SimVascular in the classroom for bioengineering education.

Vascular effects of advanced glycation end-products: content of immunohistochemically detected AGEs in radial artery samples as a predictor for arterial calcification and cardiovascular risk in asymptomatic patients with chronic kidney disease.

PubMed

Janda, Katarzyna; Krzanowski, Marcin; Gajda, Mariusz; Dumnicka, Paulina; Jasek, Ewa; Fedak, Danuta; Pietrzycka, Agata; Kuźniewski, Marek; Litwin, Jan A; Sułowicz, Władysław

2015-01-01

Our aim was to determine whether vascular deposition of advanced glycation end-products (AGEs) is associated with arterial calcification and cardiovascular mortality in chronic kidney disease (CKD) patients and to assess the relationships between vascular content of AGEs and selected clinical and biochemical parameters. The study comprised 54 CKD patients (33 hemodialyzed, 21 predialyzed). Examined parameters included BMI, incidence of diabetes, plasma fasting glucose, AGEs, soluble receptor for AGEs and 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging, serum C-reactive protein (hsCRP), plasminogen activator inhibitor-1 (PAI-1), and fetuin-A. Fragments of radial artery obtained during creation of hemodialysis access were stained for calcifications using alizarin red. AGEs deposits were identified immunohistochemically and their relative content was quantified. Vascular content of AGEs was positively correlated with BMI, hsCRP, fetuin-A, PAI-1, and DPPH scavenging in simple regression; only fetuin-A was an independent predictor in multiple regression. There was a significant positive trend in the intensity of AGEs immunostaining among patients with grades 1, 2, and 3 calcifications. AGEs immunostaining intensity predicted 3-year cardiovascular mortality irrespective of patient's age. The present study demonstrates an involvement of AGEs in the development of medial arterial calcification and the impact of arterial AGE deposition on cardiovascular mortality in CKD patients.

Design and development of multilayer vascular graft

NASA Astrophysics Data System (ADS)

Madhavan, Krishna

2011-07-01

Vascular graft is a widely-used medical device for the treatment of vascular diseases such as atherosclerosis and aneurysm as well as for the use of vascular access and pediatric shunt, which are major causes of mortality and morbidity in this world. Dysfunction of vascular grafts often occurs, particularly for grafts with diameter less than 6mm, and is associated with the design of graft materials. Mechanical strength, compliance, permeability, endothelialization and availability are issues of most concern for vascular graft materials. To address these issues, we have designed a biodegradable, compliant graft made of hybrid multilayer by combining an intimal equivalent, electrospun heparin-impregnated poly-epsilon-caprolactone nanofibers, with a medial equivalent, a crosslinked collagen-chitosan-based gel scaffold. The intimal equivalent is designed to build mechanical strength and stability suitable for in vivo grafting and to prevent thrombosis. The medial equivalent is designed to serve as a scaffold for the activity of the smooth muscle cells important for vascular healing and regeneration. Our results have shown that genipin is a biocompatible crosslinker to enhance the mechanical properties of collagen-chitosan based scaffolds, and the degradation time and the activity of smooth muscle cells in the scaffold can be modulated by the crosslinking degree. For vascular grafting and regeneration in vivo, an important design parameter of the hybrid multilayer is the interface adhesion between the intimal and medial equivalents. With diametrically opposite affinities to water, delamination of the two layers occurs. Physical or chemical modification techniques were thus used to enhance the adhesion. Microscopic examination and graft-relevant functional characterizations have been performed to evaluate these techniques. Results from characterization of microstructure and functional properties, including burst strength, compliance, water permeability and suture strength, showed that the multilayer graft possessed properties mimicking those of native vessels. Achieving these FDA-required functional properties is essential because they play critical roles in graft performances in vivo such as thrombus formation, occlusion, healing, and bleeding. In addition, cell studies and animal studies have been performed on the multilayer graft. Our results show that the multilayer graft support mimetic vascular culture of cells and the acellular graft serves as an artery equivalent in vivo to sustain the physiological conditions and promote appropriate cellular activity. In conclusion, the newly-developed hybrid multilayer graft provides a proper balance of biomechanical and biochemical properties and demonstrates the potential for the use of vascular tissue engineering and regeneration.

Does erectile tissue angioarchitecture modify with aging? An immunohistological and morphometric approach.

PubMed

Costa, Carla; Vendeira, Pedro

2008-04-01

Introduction. Erectile dysfunction is a common problem in aged men; however, which vascular cavernosal alterations occur with age progression remain unclarified. Aim. Using cavernosal tissue from rats of various ages, we aimed to thoroughly assess erectile vascular-associated morphologic, immunohistological, and morphometric alterations during aging. Methods. Male Wistar rats were divided according to age in groups of 2, 6, 12, 18, 24 months old (N = 5). Cavernosal tissue of all groups was collected and processed for morphologic evaluation, immunodetection of alpha-smooth muscle actin and von Willebrand factor and morphometric quantification of vascular and smooth muscle cell (SMC) areas. Main Outcome Measures. The morphometric assessment of age-related alterations in cavernosal vascular and SMCs using the ImageJ image-processing program. Results. Morphologic and immunohistological evaluation showed a similar structure of erectile tissue among all age groups, divided in two cavernosal bodies containing numerous sinusoidal vascular spaces surrounded by SMCs. Additionally, we observed a reduction of SMC content and an increase in the caliber of vascular spaces, with aging. This was confirmed by the morphometric quantification of the vascular and SMC areas (mean area x10(3) microm(2) +/- x10(3) standard error). Two-month-old animals had a mean vascular area of 4.21 +/- 0.51, approximately 3.5-fold less than the 6-month-old group. The differences increased when comparing the youngest groups with the 12-, 18-, and 24-month-old animals, with mean measurements of 18.99 +/- 1.91, 25.23 +/- 2.76, and 26.34 +/- 2.97. Conversely, SMC areas progressively decreased between 2- and 6-month-old animals, from 6.75 +/- 0.90 to 6.38 +/- 1.24. The elderly 12-, 18-, and 24-month-old groups presented an approximated 1.5-fold reduction on SMCs area, showed by the respective measurements of 4.11 +/- 0.50, 4.01 +/- 0.35, and 4.02 +/- 0.44. Conclusions. We demonstrated that cavernosal angioarchitecture was modified with aging. The decrease in SMCs and the considerable enlargement of vascular lumens may limit the basic function of penile vascular tree in the elderly.

Non-vascularized free toe phalanx transplantation in the treatment of symbrachydactyly and constriction ring syndrome.

PubMed

Gohla, T; Metz, Ch; Lanz, U

2005-10-01

Forty-eight patients underwent a total number of 113 non-vascularized free toe phalanx transplantations for congenital short digits between 1975 and 2003, a mean number of 2.3 transplanted phalanges per patient. The mean age at the time of initial surgery was 3.6 years (range 6 months to 21 years). The follow-up time ranged from 4 months to 14 years with a mean of 6 years. Sixty-four phalanges showed radiographically measured growth, 22 phalanges showed signs of resorption, while 27 phalanges showed neither growth nor resorption. Resorption increased with patient age. Three patients developed donor site problems. The optimum timing for initial surgery is as early as possible because of the safer and greater growth potential and less resorption of the transplanted phalanges. Non-vascularized free toe phalanx transplantations offer a simple and safe method of lengthening with a significant improvement of hand function.

Successful ovarian autotransplant with no vascular reanastomosis in rats.

PubMed

Barros, Flávio S V; de Oliveira, Rodrigo M; Alves, Felipe M T; Sampaio, Marcos; Geber, Selmo

2008-12-15

Preservation of ovarian functions in woman with premature ovarian failure remains an issue in reproductive medicine. Hormone replacement therapy for maintaining endocrine functions, and cryopreservation of embryos or oocytes for those who wish pregnancy, are some of the choices. However, ovarian transplantation is a more physiological alternative, although problems related to ovarian ischemia have been reported. Herein, we investigated the viability of autologous transplantation of the ovarian tissue into the rat peritoneum, without vascular reanastomosis. Twenty animals in the study group had both ovaries excised, and each ovary was dissected into two halves. A half of an ovary was autotransplanted to the peritoneal surface, closely located to the left epigastric vessels. This simple procedure does not require surgical vascular reanastomosis while it maintains appropriate follicular growth and therefore should be further considered as an alternative for women undergoing oophorectomy, not only to maintain endocrine functions but also for fertility preservation.

[The current approach to hemangiomas and vascular malformations of the head and neck].

PubMed

Raveh, E; Waner, M; Kornreich, L; Segal, K; Ben-Amitai, D; Kalish, E; Lapidot, M; Mimon, S; Shalev, B; Feinmesser, R

2002-09-01

Though most hemangiomas do not need treatment, a significant minority are associated with complications and external deformities that demand intervention. Steroids play an important role in therapy, but not infrequently afford only partial and temporary benefit. Thanks to improvements in the surgical approach and equipment, hemostasis control devices and laser techniques, we can now treat patients who would otherwise go untreated. Moreover, in certain cases, we can now recommend earlier intervention, saving patients from years of living with deformities and the concomitant psychosocial problems. Vascular anomalies of the head and neck include venular, venous and arteriovenous malformations. These lesions are slow growing vascular ectasia that never involute spontaneously and almost always require intervention. Treatment includes laser therapy, injection of sclerosing agents, embolization through angiography and surgery, which in many cases is the only definitive treatment. We present the current treatment approach and describe our experience in the treatment of 16 patients.

Splenic Injury During Percutaneous Nephrolithotomy

PubMed Central

Thomas, Anil A.; Pierce, Gregory; Walsh, R. Matthew; Sands, Mark

2009-01-01

Background: Injury to the spleen is a recognized complication during percutaneous renal access due to the close anatomical relationship of the spleen and the left kidney. However, transsplenic renal access is a rare complication of percutaneous nephrolithotomy and can also result in considerable morbidity, often requiring emergent splenectomy. Methods: We present our experience with splenic injury during percutaneous nephrolithotomy managed conservatively with the use of a collagen-thrombin hemostatic sealant (D-Stat; Vascular Solutions, Inc., Minneapolis, MN) after delayed removal of the nephrostomy tubes. Results: The patient had an uneventful recovery and was discharged home on postoperative day 6. Conclusion: In select hemodynamically stable patients, nonoperative management with the adjunctive use of hemostatic sealants may be considered. PMID:19660224

[Peripheral vascular injuries in polytrauma].

PubMed

Richter, A; Silbernik, D; Oestreich, K; Karaorman, M; Storz, L W

1995-09-01

Between 1972 und 1993 a total of 68 patients were treated at the Department of Surgery of the University Clinic of Mannheim for peripheral vascular injury resulting from multiple trauma. The average age of these patients was 31.3 years, and most of them were male (88.2%; n = 60). The injured vessels were localized evenly in all the extremities: 31 patients (45.5%) presented with arterial damage of the upper extremity, and 37 (54.5%) showed lesions along the femoro-popliteal arteries. The most frequent location of injured vessels in the multiply traumatized patient was the popliteal artery (n = 18, 26.5%), the distal part of the superficial femoral artery (n = 12, 17.6%), the brachial artery (n = 14, 20.6%) and the axillary artery (n = 10, 14.6%). The dominant cause, of trauma was road traffic accidents (72%), and 20 patients (29%) acquired their vascular injuries as motorcyclists. There were also 13 occupational accidents (19%) involving vascular injuries. In addition to a vascular trauma 34 patients (50%) had complicated fractures, and a further 34 patients (50%) had multiple fractures: 12 (17.6%) had head and brain damage, 5 (7.3%) had blunt abdominal trauma and 6 (8.8%) had blunt thoracic injury. The general amputation rate was 2.9% (n = 2). One patient died on the table of a torn off subclavian artery combined with multiple other injuries. Paresis of the plexus is a particular problem after vascular lesions of the upper extremity: in 22 patients (71%) paresis of the plexus persisted after successful vascular reconstruction (follow-up period between 3 months and 16 years, median time 3.45 years).(ABSTRACT TRUNCATED AT 250 WORDS)

[Controversy: botulinum toxin, does it prevent cutaneous aging?].

PubMed

Cohen-Letessier, A

2009-05-01

By blocking muscular contraction, even if this effect is reversible, botulinum toxin injected early and regularly to prevent aging modifies the facial traits and can result in muscular and cutaneous atrophy. Mechanical information is indispensable to cell survival and conditions the function of fibroblastic synthesis. Aging cannot be reduced to the facial lines; botulinum toxin cannot prevent the other parameters of age such as drying, pigmentation problems, vascular problems, and loss of volume.

Intracoronary stent implantation: new approach using a monorail system and new large-lumen 7F catheters from the brachial route.

PubMed

Jenny, D B; Robert, G P; Fajadet, J C; Cassagneau, B G; Marco, J

1992-04-01

In this brief report we describe a case of successful multivessel PTCA with intracoronary stent implantation using a new large-lumen 7F catheter from the left brachial approach. The application of this technique should be considered for intravascular stent implantation when anticoagulation ideally should not be interrupted or in anatomical situations limiting femoral vascular access.

A cost-effective peripheral venous port system placed at the bedside.

PubMed

Finney, R; Albrink, M H; Hart, M B; Rosemurgy, A S

1992-07-01

High costs and a paucity of available operating time have led us to seek alternatives to operatively placed vascular access systems. This prospective study is the initial report of a peripheral port system (P.A.S. PORT System, Pharmacia Deltec, Inc.) placed at the bedside. Seventy-nine patients (52 male, 27 female), ages 3-92 years, had ports implanted by surgical residents with attending supervision. Sixty-eight (86%) received the P.A.S. PORT for long-term antibiotics, antifungal, or antiviral therapy; four (5%) for TPN infusion; three (4%) for blood products; two (3%) for chemotherapy; and two (3%) for iv narcotics. Ports were placed in 10 (13%) HIV(+) patients, three (4%) who were fully anticoagulated, and one who was a hemophiliac with a platelet count of zero. Eight patients (10%) developed superficial phlebitis, all of which resolved with nonsteroidal anti-inflammatory agents within 48 hr without port removal. Seven patients (9%) had their port removed due to infection. The average hospital charge to place the P.A.S. PORT System was $1488.00 vs $2811.00 for a tunneled external chest catheter and $3729.00 for the placement of a chest port. Bedside insertion of vascular access devices can be safely performed with acceptable infection rates allowing more efficient use of hospital operating rooms and with substantial cost savings.

Analgesia by cooling vibration during venipuncture in children with cognitive impairment.

PubMed

Schreiber, Silvana; Cozzi, Giorgio; Rutigliano, Rosaria; Assandro, Paola; Tubaro, Martina; Cortellazzo Wiel, Luisa; Ronfani, Luca; Barbi, Egidio

2016-01-01

Children with cognitive impairment experience pain more frequently than healthy children and are more likely to require venipuncture or intravenous cannulation for various procedures. They are frequently unable to report pain and often receive poor pain assessment and management. This study assessed the effectiveness of physical analgesia during vascular access in children with cognitive impairments. We conducted a prospective randomised controlled study at a tertiary-level children's hospital in Italy from April to May 2015 to assess whether a cooling vibration device called Buzzy decreased pain during venipuncture and intravenous cannulation in children with cognitive impairment. None of the children had verbal skills and the main cognitive impairments were cerebral palsy, epileptic encephalopathy and genetic syndromes. We tested 70 children with a median age of nine years: 34 in the Buzzy group and 36 in the no-intervention group. Parents were trained in the use of the Noncommunicating Children's Pain Checklist--postoperative version scale, and they reported no or mild procedural pain in 32 cases (91.4%) in the Buzzy group and in 22 cases (61.1%) in the no-intervention group (p = 0.003). Cooling vibration analgesia during vascular access reduced pain in children with cognitive impairment. ©2015 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Central venous stenosis among hemodialysis patients is often not associated with previous central venous catheters.

PubMed

Kotoda, Atsushi; Akimoto, Tetsu; Kato, Maki; Kanazawa, Hidenori; Nakata, Manabu; Sugase, Taro; Ogura, Manabu; Ito, Chiharu; Sugimoto, Hideharu; Muto, Shigeaki; Kusano, Eiji

2011-01-01

It is widely assumed that central venous stenosis (CVS) is most commonly associated with previous central venous catheterization among the chronic hemodialysis (HD) patients. We evaluated the validity of this assumption in this retrospective study. The clinical records from 2,856 consecutive HD patients with vascular access failure during a 5-year period were reviewed, and a total of 26 patients with symptomatic CVS were identified. Combined with radiological findings, their clinical characteristics were examined. Only seven patients had a history of internal jugular dialysis catheterization. Diagnostic multidetector row computed tomography angiography showed that 7 of the 19 patients with no history of catheterization had left innominate vein stenosis due to extrinsic compression between the sternum and arch vessels. These patients had a shorter period from the time of creation of the vascular access to the initial referral (9.2 ± 7.6 months) than the rest of the patients (35.5 ± 18.6 months, p = 0.0017). Our findings suggest that cases without a history of central venous catheterization may not be rare among the HD patients with symptomatic CVS. However, those still need to be confirm by larger prospective studies of overall chronic HD patients with symptomatic CVS.

Microsurgical anatomy of the transsylvian translimen insula approach to the mediobasal temporal lobe: Technical considerations and case illustration.

PubMed

Straus, David; Byrne, Richard W; Sani, Sepehr; Serici, Anthony; Moftakhar, Roham

2013-01-01

Various vascular, neoplastic, and epileptogenic pathologies occur in the mediobasal temporal region. A transsylvian translimen insula (TTI) approach can be used as an alternative to temporal transcortical approach to the mediobasal temporal region. The aim of this study was to demonstrate the surgical anatomy of the TTI approach, including the gyral, sulcal, and vascular anatomy in and around the limen insula. The use of this approach is illustrated in the resection of a complex arteriovenous malformation. The TTI approach to the mediobasal temporal region was performed on three silicone-injected cadaveric heads. The gyral, sulcal, and arterial anatomy of the limen insula was studied in six formalin-fixed injected hemispheres. The TTI approach provided access to the anterior and middle segments of the mediobasal temporal lobe region as well as allowing access to temporal horn of the lateral ventricle. Using this approach we were able to successfully resect an arteriovenous malformation of the dominant medial temporal lobe. The TTI approach provides a viable surgical route to the region of mediobasal temporal lobe region. This approach offers an advantage over the temporal transcortical route in that there is less risk of damage to optic radiations and speech area in the dominant hemisphere.

Evaluation of the psychometric properties of the phlebitis and infiltration scales for the assessment of complications of peripheral vascular access devices.

PubMed

Groll, Dianne; Davies, Barbara; Mac Donald, Joan; Nelson, Susanne; Virani, Tazim

2010-01-01

To prevent complications from peripheral vascular access device (PVAD) therapy, the Infusion Nurses Society (INS) developed 2 scales to measure the extent and severity of phlebitis and infiltration in PVADs. This study evaluated the psychometric properties of these scales to validate them with respect to their interrater reliability, concurrent validity, feasibility, and acceptability. A total of 182 patients at 2 sites were enrolled, and 416 observations of PVAD sites were made. Two nurses independently rated each PVAD site for the presence or absence of phlebitis and/or infiltration by using the INS scales. The interrater reliability was calculated, as was the agreement of the observed versus charted incidence of phlebitis and infiltration (concurrent validity) and the ease of use of the scales (feasibility, acceptability). Interrater reliability for both the Phlebitis and Infiltration scales and concurrent validity were found to be statistically significant (P < .05). The study nurses reported the scales to be easy to use, taking an average of 1.3 minutes to complete both. The importance of valid measures for use in research cannot be underestimated. The INS Phlebitis and Infiltration scales have been shown to be easy to use, valid, and reliable scales.

Preoperative computer simulation for planning of vascular access surgery in hemodialysis patients.

PubMed

Zonnebeld, Niek; Huberts, Wouter; van Loon, Magda M; Delhaas, Tammo; Tordoir, Jan H M

2017-03-06

The arteriovenous fistula (AVF) is the preferred vascular access for hemodialysis patients. Unfortunately, 20-40% of all constructed AVFs fail to mature (FTM), and are therefore not usable for hemodialysis. AVF maturation importantly depends on postoperative blood volume flow. Predicting patient-specific immediate postoperative flow could therefore support surgical planning. A computational model predicting blood volume flow is available, but the effect of blood flow predictions on the clinical endpoint of maturation (at least 500 mL/min blood volume flow, diameter of the venous cannulation segment ≥4 mm) remains undetermined. A multicenter randomized clinical trial will be conducted in which 372 patients will be randomized (1:1 allocation ratio) between conventional healthcare and computational model-aided decision making. All patients are extensively examined using duplex ultrasonography (DUS) during preoperative assessment (12 venous and 11 arterial diameter measurements; 3 arterial volume flow measurements). The computational model will predict patient-specific immediate postoperative blood volume flows based on this DUS examination. Using these predictions, the preferred AVF configuration is recommended for the individual patient (radiocephalic, brachiocephalic, or brachiobasilic). The primary endpoint is FTM rate at six weeks in both groups, secondary endpoints include AVF functionality and patency rates at 6 and 12 months postoperatively. ClinicalTrials.gov (NCT02453412), and ToetsingOnline.nl (NL51610.068.14).

IFLA General Conference, 1986. Pre-Conference Seminar on Automated Systems for Access to Multilingual and Multiscript Library materials: Problems and Solutions. Papers.

ERIC Educational Resources Information Center

International Federation of Library Associations and Institutions, The Hague (Netherlands).

A seminar which considered problems and solutions regarding automated systems for access to multilingual and multiscript library materials was held as a pre-session before the IFLA general conference in 1986. Papers presented include: (1) "Romanized and Transliterated Databases of Asian Language Materials--History, Problems, and…

Video Game Access, Parental Rules, and Problem Behavior: A Study of Boys with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Engelhardt, Christopher R.; Mazurek, Micah O.

2014-01-01

Environmental correlates of problem behavior among individuals with autism spectrum disorder remain relatively understudied. The current study examined the contribution of in-room (i.e. bedroom) access to a video game console as one potential correlate of problem behavior among a sample of 169 boys with autism spectrum disorder (ranging from 8 to…

MR-guided endovascular interventions: a comprehensive review on techniques and applications.

PubMed

Kos, Sebastian; Huegli, Rolf; Bongartz, Georg M; Jacob, Augustinus L; Bilecen, Deniz

2008-04-01

The magnetic resonance (MR) guidance of endovascular interventions is probably one of the greatest challenges of clinical MR research. MR angiography is not only an imaging tool for the vasculature but can also simultaneously depict high tissue contrast, including the differentiation of the vascular wall and perivascular tissues, as well as vascular function. Several hurdles had to be overcome to allow MR guidance for endovascular interventions. MR hardware and sequence design had to be developed to achieve acceptable patient access and to allow real-time or near real-time imaging. The development of interventional devices, both applicable and safe for MR imaging (MRI), was also mandatory. The subject of this review is to summarize the latest developments in real-time MRI hardware, MRI, visualization tools, interventional devices, endovascular tracking techniques, actual applications and safety issues.

The Integrity bare-metal stent made by continuous sinusoid technology.

PubMed

Turco, Mark A

2011-05-01

The Integrity Coronary Stent System (Medtronic Vascular, CA, USA) is a low-profile, open-cell, cobalt-chromium-alloy advanced bare-metal iteration of the well-known Driver/Micro-Driver Coronary Stent System (Medtronic Vascular). The Integrity stent is made with a process called continuous sinusoid technology. This process allows stent construction via wrapping a single thin strand of wire around a mandrel in a sinusoid configuration, with laser fusion of adjacent crowns. The wire-forming process and fusion pattern provide the stent with a continuous preferential bending plane, intended to allow easier access to, and smoother tracking within, distal and tortuous vessels while radial strength is maintained. Continuous sinusoid technology represents innovation in the design of stent platforms and will provide a future stent platform for newer technology, including drug-eluting stent platforms, drug-filled stents and core wire stents.

Herbarium of vascular plants collection of the university of extremadura (Spain).

PubMed

Espinosa, Marta; López, Josefa

2013-01-01

The herbarium of University of Extremadura (UNEX Herbarium) is formed by 36451 specimens of vascular plants whose main origin is the autonomous region of Extremadura (Spain) and Portugal, although it also contains a smaller number of specimens from different places, including the rest of peninsular Spain, the Baleares Islands, the Macaronesian region (Canary Islands, Madeira and Azores), northwest of Africa (Morocco) and Brazil. 98% of the total records are georeferenced. It is an active collection in continuous growth. Its data can be accessed through the GBIF data portal at http://data.gbif.org/datasets/resource/255 and http://www.eweb.unex.es/eweb/botanica/herbario/. This paper describes the specimen associated data set of the UNEX Herbarium, with an objective to disseminate the data contained in a data set with potential users, and promote the multiple uses of the data.

Interventional radiology in infancy.

PubMed

Barnacle, Alex M

2014-11-01

Interventional radiology (IR) is an emerging sub-speciality within paediatric medicine. In adult care, IR is largely centred on the management of vascular disease but in paediatric practice, IR applications are varied and increasingly innovative, making this an exciting field to be a part of. IR has a central role both in the day to day care of sick children, from long term IV access provision to feeding tube insertions, and in the acute management of critically ill infants, such as those with overwhelming liver disease, neonatal tumours and vascular malformations. Paediatric IR faces a unique set of challenges, developing or modifying techniques and equipment for use in very small patients, training professionals to take the speciality forward and, most importantly, convincing paediatricians and healthcare institutions to create opportunities for IR to make a difference. Copyright © 2014 Elsevier Ltd. All rights reserved.

Large-for-size liver transplant: a single-center experience.

PubMed

Akdur, Aydincan; Kirnap, Mahir; Ozcay, Figen; Sezgin, Atilla; Ayvazoglu Soy, Hatice Ebru; Karakayali Yarbug, Feza; Yildirim, Sedat; Moray, Gokhan; Arslan, Gulnaz; Haberal, Mehmet

2015-04-01

The ideal ratio between liver transplant graft mass and recipient body weight is unknown, but the graft probably must weigh 0.8% to 2.0% recipient weight. When this ratio > 4%, there may be problems due to large-for-size transplant, especially in recipients < 10 kg. This condition is caused by discrepancy between the small abdominal cavity and large graft and is characterized by decreased blood supply to the liver graft and graft dysfunction. We evaluated our experience with large-for-size grafts. We retrospectively evaluated 377 orthotopic liver transplants that were performed from 2001-2014 in our center. We included 188 pediatric transplants in our study. There were 58 patients < 10 kg who had living-donor living transplant with graft-to-bodyweight ratio > 4%. In 2 patients, the abdomen was closed with a Bogota bag. In 5 patients, reoperation was performed due to vascular problems and abdominal hypertension, and the abdomen was closed with a Bogota bag. All Bogota bags were closed in 2 weeks. After closing the fascia, 10 patients had vascular problems that were diagnosed in the operating room by Doppler ultrasonography, and only the skin was closed without fascia closure. No graft loss occurred due to large-for-size transplant. There were 8 patients who died early after transplant (sepsis, 6 patients; brain death, 2 patients). There was no major donor morbidity or donor mortality. Large-for-size graft may cause abdominal compartment syndrome due to the small size of the recipient abdominal cavity, size discrepancies in vascular caliber, insufficient portal circulation, and disturbance of tissue oxygenation. Abdominal closure with a Bogota bag in these patients is safe and effective to avoid abdominal compartment syndrome. Early diagnosis by ultrasonography in the operating room after fascia closure and repeated ultrasonography at the clinic may help avoid graft loss.

Endovascular interventions for central vein stenosis.

PubMed

Agarwal, Anil K

2015-12-01

Central vein stenosis is common because of the placement of venous access and cardiac intravascular devices and compromises vascular access for dialysis. Endovascular intervention with angioplasty and/or stent placement is the preferred approach, but the results are suboptimal and limited. Primary patency after angioplasty alone is poor, but secondary patency can be maintained with repeated angioplasty. Stent placement is recommended for quick recurrence or elastic recoil of stenosis. Primary patency of stents is also poor, though covered stents have recently shown better patency than bare metal stents. Secondary patency requires repeated intervention. Recanalization of occluded central veins is tedious and not always successful. Placement of hybrid graft-catheter with a combined endovascular surgical approach can maintain patency in many cases. In the presence of debilitating symptoms, palliative approach with endovascular banding or occlusion of the access may be necessary. Prevention of central vein stenosis is the most desirable strategy.

Very Low Intravenous Contrast Volume Protocol for Computed Tomography Angiography Providing Comprehensive Cardiac and Vascular Assessment Prior to Transcatheter Aortic Valve Replacement in Patients with Chronic Kidney Disease

PubMed Central

Pulerwitz, Todd C.; Khalique, Omar K.; Nazif, Tamim N.; Rozenshtein, Anna; Pearson, Gregory D.N.; Hahn, Rebecca T.; Vahl, Torsten P.; Kodali, Susheel K.; George, Isaac; Leon, Martin B.; D'Souza, Belinda; Po, Ming Jack; Einstein, Andrew J.

2016-01-01

Background Transcatheter aortic valve replacement (TAVR) is a lifesaving procedure for many patients high risk for surgical aortic valve replacement. The prevalence of chronic kidney disease (CKD) is high in this population, and thus a very low contrast volume (VLCV) computed tomography angiography (CTA) protocol providing comprehensive cardiac and vascular imaging would be valuable. Methods 52 patients with severe, symptomatic aortic valve disease, undergoing pre-TAVR CTA assessment from 2013-4 at Columbia University Medical Center were studied, including all 26 patients with CKD (eGFR<30mL/min) who underwent a novel VLCV protocol (20mL of iohexol at 2.5mL/s), and 26 standard-contrast-volume (SCV) protocol patients. Using a 320-slice volumetric scanner, the protocol included ECG-gated volume scanning of the aortic root followed by medium-pitch helical vascular scanning through the femoral arteries. Two experienced cardiologists performed aortic annulus and root measurements. Vascular image quality was assessed by two radiologists using a 4-point scale. Results VLCV patients had mean(±SD) age 86±6.5, BMI 23.9±3.4 kg/m2 with 54% men; SCV patients age 83±8.8, BMI 28.7±5.3 kg/m2, 65% men. There was excellent intra- and inter-observer agreement for annular and root measurements, and excellent agreement with 3D-transesophageal echocardiographic measurements. Both radiologists found diagnostic-quality vascular imaging in 96% of VLCV and 100% of SCV cases, with excellent inter-observer agreement. Conclusions This study is the first of its kind to report the feasibility and reproducibility of measurements for a VLCV protocol for comprehensive pre-TAVR CTA. There was excellent agreement of cardiac measurements and almost all studies were diagnostic quality for vascular access assessment. PMID:27061253

Construction and validation of a scale of assessment of self-care behaviours anticipatory to creation of arteriovenous fistula.

PubMed

Sousa, Clemente Neves; Figueiredo, Maria Henriqueta; Dias, Vanessa Filipa; Teles, Paulo; Apóstolo, João Luís

2015-12-01

We developed a scale to assess the self-care behaviours developed by patients with end-stage renal disease to preserve the vascular network prior to construction of arteriovenous fistula. The possibility of creation of an arteriovenous fistula depends on the existence of an arterial and venous network in good condition, namely the size and elasticity of the vessels. It is essential to teach the person to develop self-care behaviours for the preservation of the vascular network, regardless of the modality of dialysis selected. Methodological study. The scale was developed based on clinical experience and research conducted by the researcher in the area of the vascular access for haemodialysis. The content of the scale was judged by two panels of experts for content validity. The revised version of the scale was administered to a convenience sample of 90 patients with end-stage renal disease. In the statistical analysis, we used the Cronbach's alpha, the Kaiser-Meyer-Olkin and scree plot and the principal component analysis with varimax rotation. A principal component analysis confirmed the univariate structure of the scale (KMO = 0·759, Bartlett's sphericity test-approximate χ(2) 142·201, p < 0·000). Cronbach's α is 0·831, varying between 0·711-0·879. This scale revealed properties that allow its use to assess the patients self-care behaviours regarding the preservation of the vascular network. This scale can be used to evaluate educational programmes for the development of self-care behaviours in the preservation of vascular network. This scale can identify not only the patients that are able to take care of their vascular network but also the proportion of patients who are not able to do it, that need to be educated. © 2015 John Wiley & Sons Ltd.

Land Development and Subdivision Regulations that Support Access Management

DOT National Transportation Integrated Search

1993-01-01

This report examines the role of the comprehensive plan in developing an access : management program, aspects of current regulatory practice that contribute to : access problems, and regulatory techniques that support access management : principles. ...

Spinal Cord Injury-Induced Dysautonomia via Plasticity in Paravertebral Sympathetic Postganglionic

DTIC Science & Technology

2017-10-01

their near anatomical inaccessibility. We have solved the accessibility problem with a strategic methodological advance. We will determine the extent...inaccessibility. We have solved the accessibility problem with a strategic methodological advance. We will determine the extent to which paravertebral

Antheraea pernyi silk fibroin for targeted gene delivery of VEGF165-Ang-1 with PEI.

PubMed

Ma, Caili; Lv, Linlin; Liu, Yu; Yu, Yanni; You, Renchuan; Yang, Jicheng; Li, Mingzhong

2014-06-01

Vascularization is a crucial challenge in tissue engineering. One solution for this problem is to implant scaffolds that contain functional genes that promote vascularization by providing angiogenic growth factors via a gene delivery carrier. Poly(ethylenimine) (PEI) is a gene delivery carrier with high transfection efficiency but with cytotoxicity. To solve this problem, we utilized Antheraea pernyi silk fibroin (ASF), which has favorable cytocompatibility and biodegradability, RGD sequences and a negative charge, in conjunction with PEI, as the delivery vector for vascular endothelial growth factor (VEGF) 165-angiopoietin-1 (Ang-1) dual gene simultaneous expression plasmid, creating an ASF/PEI/pDNA complex. The results suggested that the zeta potential of the ASF/PEI/pDNA complex was significantly lower than that of the PEI/pDNA complex. Decreased nitrogen and increased oxygen on the surface of the complex demonstrated that the ASF had successfully combined with the surface of the PEI/pDNA. Furthermore, the complexes resisted digestion by nucleic acid enzymes and degradation by serum. L929 cells were cultured and transfected in vitro and improved cytotoxicity was found when the cells were transfected with ASF/PEI/pDNA compared with PEI/pDNA. In addition, the transfection efficiency and VEGF secretion increased. In general, this study provides a novel method for decreasing the cytotoxicity of PEI gene delivery vectors and increasing transfection efficiency of angiogenesis-related genes.

Shock-induced bubble collapse in a vessel: Implications for vascular injury in shockwave lithotripsy

NASA Astrophysics Data System (ADS)

Coralic, Vedran; Colonius, Tim

2014-11-01

In shockwave lithotripsy, shocks are repeatedly focused on kidney stones so to break them. The process leads to cavitation in tissue, which leads to hemorrhage. We hypothesize that shock-induced collapse (SIC) of preexisting bubbles is a potential mechanism for vascular injury. We study it numerically with an idealized problem consisting of the three-dimensional SIC of an air bubble immersed in a cylindrical water column embedded in gelatin. The gelatin is a tissue simulant and can be treated as a fluid due to fast time scales and small spatial scales of collapse. We thus model the problem as a compressible multicomponent flow and simulate it with a shock- and interface-capturing numerical method. The method is high-order, conservative and non-oscillatory. Fifth-order WENO is used for spatial reconstruction and an HLLC Riemann solver upwinds the fluxes. A third-order TVD-RK scheme evolves the solution. We evaluate the potential for injury in SIC for a range of pressures, bubble and vessel sizes, and tissue properties. We assess the potential for injury by comparing the finite strains in tissue, obtained by particle tracking, to ultimate strains from experiments. We conclude that SIC may contribute to vascular rupture and discuss the smallest bubble sizes needed for injury. This research was supported by NIH Grant No. 2PO1DK043881 and utilized XSEDE, which is supported by NSF Grant No. OCI-1053575.

Leaf hydraulics II: vascularized tissues.

PubMed

Rockwell, Fulton E; Holbrook, N Michele; Stroock, Abraham D

2014-01-07

Current models of leaf hydration employ an Ohm's law analogy of the leaf as an ideal capacitor, neglecting the resistance to flow between cells, or treat the leaf as a plane sheet with a source of water at fixed potential filling the mid-plane, neglecting the discrete placement of veins as well as their resistance. We develop a model of leaf hydration that considers the average conductance of the vascular network to a representative areole (region bounded by the vascular network), and represent the volume of tissue within the areole as a poroelastic composite of cells and air spaces. Solutions to the 3D flow problem are found by numerical simulation, and these results are then compared to 1D models with exact solutions for a range of leaf geometries, based on a survey of temperate woody plants. We then show that the hydration times given by these solutions are well approximated by a sum of the ideal capacitor and plane sheet times, representing the time for transport through the vasculature and tissue respectively. We then develop scaling factors relating this approximate solution to the 3D model, and examine the dependence of these scaling factors on leaf geometry. Finally, we apply a similar strategy to reduce the dimensions of the steady state problem, in the context of peristomatal transpiration, and consider the relation of transpirational gradients to equilibrium leaf water potential measurements. © 2013 Published by Elsevier Ltd. All rights reserved.

The economics of vein disease.

PubMed

Sales, Clifford M; Podnos, Joan; Levison, Jonathan

2007-09-01

The management of cosmetic vein problems requires a very different approach than that for the majority of most other vascular disorders that occur in a vascular surgery practice. This article focuses on the business aspects of a cosmetic vein practice, with particular attention to the uniqueness of these issues. Managing patient expectations is critical to the success of a cosmetic vein practice. Maneuvering within the insurance can be difficult and frustrating for both the patient and the practice. Practices should use cost accounting principles to evaluate the success of their vein work. Vein surgery--especially if performed within the office--can undergo an accurate break-even analysis to determine its profitability.

EACTS day in the new EACTS House.

PubMed

von Segesser, Ludwig K

2013-01-01

There is no doubt that the European Association for Cardio-Thoracic Surgery is a success story. In 2011, we celebrated the 25th anniversary of this professional organization. In 2012, we will celebrate the 25th anniversary of the European Journal of Cardio-Thoracic Surgery. In addition, two other journals have been initiated, Interactive CardioVascular and Thoracic Surgery and the Multimedia Manual of Cardio-Thoracic Surgery, and all of them can be accessed through CTSnet (www.ctsnet.org). The most recent development was the birth of EACTS House, and it was to celebrate the official opening of EACTS House on 10 February 2011, that we held the second Strategic meeting, 'EACTS in the Future'. On this occasion, the EACTS council and delegates of the EACTS Domains (Domain of Thoracic Disease, Domain of Vascular Disease, Domain of Congenital Cardiac Disease and Domain of Adult Cardiac Disease) came together with representative thoracic and cardio-vascular surgeons from North America, Asia and BRICS countries as well as senior managers from industry in order to decide where to go from there. As a basis for starting the discussions, a sector analysis of the activities of the Department of Cardio-Vascular Surgery at CHUV in Lausanne, Switzerland was performed in order to identify the trends in the activities of our group of surgeons by pulling the consolidated data for the period running from 1 January 1995 to 31 December 2010. Interestingly enough, the most frequent procedures like coronary artery bypass graft and valve repair/replacement did not increase despite a growing programme. In our setting, the compensation came mainly from vascular surgery and mechanical circulatory support. These data have to be put in perspective by the reports provided by the EACTS domain chairs in order to identify the challenges and opportunities for the future development of our specialties.

The fluoroscopy time, door to balloon time, contrast volume use and prevalence of vascular access site failure with transradial versus transfemoral approach in ST segment elevation myocardial infarction: A systematic review & meta-analysis.

PubMed

Singh, Sukhchain; Singh, Mukesh; Grewal, Navsheen; Khosla, Sandeep

2015-12-01

The authors aimed to conduct first systematic review and meta-analysis in STEMI patients evaluating vascular access site failure rate, fluoroscopy time, door to balloon time and contrast volume used with transradial vs transfemoral approach (TRA vs TFA) for PCI. The PubMed, CINAHL, clinicaltrials.gov, Embase and CENTRAL databases were searched for randomized trials comparing TRA versus TFA. Random effect models were used to conduct this meta-analysis. Fourteen randomized trials comprising 3758 patients met inclusion criteria. The access site failure rate was significantly higher TRA compared to TFA (RR 3.30, CI 2.16-5.03; P=0.000). Random effect inverse variance weighted prevalence rate meta-analysis showed that access site failure rate was predicted to be 4% (95% CI 3.0-6.0%) with TRA versus 1% (95% CI 0.0-1.0 %) with TFA. Door to balloon time (Standardized mean difference [SMD] 0.30 min, 95% CI 0.23-0.37 min; P=0.000) and fluoroscopy time (Standardized mean difference 0.14 min, 95% CI 0.06-0.23 min; P=0.001) were also significantly higher in TRA. There was no difference in the amount of contrast volume used with TRA versus TFA (SMD -0.05 ml, 95% CI -0.14 to 0.04 ml; P=0.275). Statistical heterogeneity was low in cross-over rate and contrast volume use, moderate in fluoroscopy time but high in the door to balloon time comparison. Operators need to consider higher cross-over rate with TRA compared to TFA in STEMI patients while attempting PCI. Fluoroscopy and door to balloon times are negligibly higher with TRA but there is no difference in terms of contrast volume use. Copyright © 2015 Elsevier Inc. All rights reserved.

The French Muséum national d'histoire naturelle vascular plant herbarium collection dataset

NASA Astrophysics Data System (ADS)

Le Bras, Gwenaël; Pignal, Marc; Jeanson, Marc L.; Muller, Serge; Aupic, Cécile; Carré, Benoît; Flament, Grégoire; Gaudeul, Myriam; Gonçalves, Claudia; Invernón, Vanessa R.; Jabbour, Florian; Lerat, Elodie; Lowry, Porter P.; Offroy, Bérangère; Pimparé, Eva Pérez; Poncy, Odile; Rouhan, Germinal; Haevermans, Thomas

2017-02-01

We provide a quantitative description of the French national herbarium vascular plants collection dataset. Held at the Muséum national d'histoire naturelle, Paris, it currently comprises records for 5,400,000 specimens, representing 90% of the estimated total of specimens. Ninety nine percent of the specimen entries are linked to one or more images and 16% have field-collecting information available. This major botanical collection represents the results of over three centuries of exploration and study. The sources of the collection are global, with a strong representation for France, including overseas territories, and former French colonies. The compilation of this dataset was made possible through numerous national and international projects, the most important of which was linked to the renovation of the herbarium building. The vascular plant collection is actively expanding today, hence the continuous growth exhibited by the dataset, which can be fully accessed through the GBIF portal or the MNHN database portal (available at: https://science.mnhn.fr/institution/mnhn/collection/p/item/search/form). This dataset is a major source of data for systematics, global plants macroecological studies or conservation assessments.

The French Muséum national d'histoire naturelle vascular plant herbarium collection dataset.

PubMed

Le Bras, Gwenaël; Pignal, Marc; Jeanson, Marc L; Muller, Serge; Aupic, Cécile; Carré, Benoît; Flament, Grégoire; Gaudeul, Myriam; Gonçalves, Claudia; Invernón, Vanessa R; Jabbour, Florian; Lerat, Elodie; Lowry, Porter P; Offroy, Bérangère; Pimparé, Eva Pérez; Poncy, Odile; Rouhan, Germinal; Haevermans, Thomas

2017-02-14

We provide a quantitative description of the French national herbarium vascular plants collection dataset. Held at the Muséum national d'histoire naturelle, Paris, it currently comprises records for 5,400,000 specimens, representing 90% of the estimated total of specimens. Ninety nine percent of the specimen entries are linked to one or more images and 16% have field-collecting information available. This major botanical collection represents the results of over three centuries of exploration and study. The sources of the collection are global, with a strong representation for France, including overseas territories, and former French colonies. The compilation of this dataset was made possible through numerous national and international projects, the most important of which was linked to the renovation of the herbarium building. The vascular plant collection is actively expanding today, hence the continuous growth exhibited by the dataset, which can be fully accessed through the GBIF portal or the MNHN database portal (available at: https://science.mnhn.fr/institution/mnhn/collection/p/item/search/form). This dataset is a major source of data for systematics, global plants macroecological studies or conservation assessments.

Does cross-taxon analysis show similarity in diversity patterns between vascular plants and bryophytes? Some answers from a literature review.

PubMed

Bagella, Simonetta

2014-04-01

The objective of this study was to clarify the taxon surrogacy hypothesis relative to vascular plants and bryophytes. A literature review was conducted to obtain papers that met the following criteria: (i) they examined species richness values; or (ii) they evaluated the species richness within the same study sites, or under the same spatial variation conditions. Twenty-seven papers were accessed. The richness of the two taxa, compared in 32 cases, positively co-varied in about half of the comparisons. The response to the spatial variation in environmental or human-induced factors of the two taxa in terms of species richness was rather variable. Based on current knowledge, the main documented findings regard forest habitats and nival gradients. In forest habitats, co-variation in species richness is likely when similar environments are analysed and seems to be strengthened for boreal forests. Along the nival gradient, a different response in terms of richness of the two taxa suggests that vascular plants cannot be considered good surrogates for bryophytes. Copyright © 2014 Académie des sciences. Published by Elsevier SAS. All rights reserved.

The French Muséum national d’histoire naturelle vascular plant herbarium collection dataset

PubMed Central

Le Bras, Gwenaël; Pignal, Marc; Jeanson, Marc L.; Muller, Serge; Aupic, Cécile; Carré, Benoît; Flament, Grégoire; Gaudeul, Myriam; Gonçalves, Claudia; Invernón, Vanessa R.; Jabbour, Florian; Lerat, Elodie; Lowry, Porter P.; Offroy, Bérangère; Pimparé, Eva Pérez; Poncy, Odile; Rouhan, Germinal; Haevermans, Thomas

2017-01-01

We provide a quantitative description of the French national herbarium vascular plants collection dataset. Held at the Muséum national d’histoire naturelle, Paris, it currently comprises records for 5,400,000 specimens, representing 90% of the estimated total of specimens. Ninety nine percent of the specimen entries are linked to one or more images and 16% have field-collecting information available. This major botanical collection represents the results of over three centuries of exploration and study. The sources of the collection are global, with a strong representation for France, including overseas territories, and former French colonies. The compilation of this dataset was made possible through numerous national and international projects, the most important of which was linked to the renovation of the herbarium building. The vascular plant collection is actively expanding today, hence the continuous growth exhibited by the dataset, which can be fully accessed through the GBIF portal or the MNHN database portal (available at: https://science.mnhn.fr/institution/mnhn/collection/p/item/search/form). This dataset is a major source of data for systematics, global plants macroecological studies or conservation assessments. PMID:28195585

Computer-aided detection of basal cell carcinoma through blood content analysis in dermoscopy images

NASA Astrophysics Data System (ADS)

Kharazmi, Pegah; Kalia, Sunil; Lui, Harvey; Wang, Z. Jane; Lee, Tim K.

2018-02-01

Basal cell carcinoma (BCC) is the most common type of skin cancer, which is highly damaging to the skin at its advanced stages and causes huge costs on the healthcare system. However, most types of BCC are easily curable if detected at early stage. Due to limited access to dermatologists and expert physicians, non-invasive computer-aided diagnosis is a viable option for skin cancer screening. A clinical biomarker of cancerous tumors is increased vascularization and excess blood flow. In this paper, we present a computer-aided technique to differentiate cancerous skin tumors from benign lesions based on vascular characteristics of the lesions. Dermoscopy image of the lesion is first decomposed using independent component analysis of the RGB channels to derive melanin and hemoglobin maps. A novel set of clinically inspired features and ratiometric measurements are then extracted from each map to characterize the vascular properties and blood content of the lesion. The feature set is then fed into a random forest classifier. Over a dataset of 664 skin lesions, the proposed method achieved an area under ROC curve of 0.832 in a 10-fold cross validation for differentiating basal cell carcinomas from benign lesions.

A national study of neighbourhood access to gambling opportunities and individual gambling behaviour.

PubMed

Pearce, J; Mason, K; Hiscock, R; Day, P

2008-10-01

To investigate associations between neighbourhood accessibility to gambling outlets (non-casino gaming machine locations, sports betting venues and casinos) and individual gambling behaviour in New Zealand. A Geographical Information Systems (GIS) measure of neighbourhood access to gambling venues. Two-level logistic regression models were fitted to examine the effects of neighbourhood access on individual gambling behaviour after controlling for potential individual- and neighbourhood-level confounding factors. 38,350 neighbourhoods across New Zealand. 12,529 respondents of the 2002/03 New Zealand Health Survey. Compared with those living in the quartile of neighbourhoods with the furthest access to a gambling venue, residents living in the quartile of neighbourhoods with the closest access were more likely (adjusted for age, sex, socio-economic status at the individual-level and deprivation, urban/rural status at the neighbourhood-level) to be a gambler (OR 1.60, 95% CI 1.20 to 2.15) or problem gambler (OR 2.70, 95% CI 1.03 to 7.05). When examined independently, neighbourhood access to venues with non-casino gaming machines (gambling: OR 1.67, 95% CI 1.28 to 2.18; problem gambling: OR 2.71, 95% CI 1.45 to 5.07) and sports betting venues (gambling: OR 1.67, 95% CI 1.28 to 2.18; problem gambling: OR 2.71, 95% CI 1.45 to 5.07) were similarly related. Neighbourhood access to opportunities for gambling is related to gambling and problem gambling behaviour, and contributes substantially to neighbourhood inequalities in gambling over and above-individual level characteristics.

Provision of foot health services for people with rheumatoid arthritis in New South Wales: a web-based survey of local podiatrists

PubMed Central

2013-01-01

Background It is unclear if podiatric foot care for people with rheumatoid arthritis (RA) in New South Wales (NSW) meets current clinical recommendations. The objective of this study was to survey podiatrists’ perceptions of the nature of podiatric foot care provision for people who have RA in NSW. Methods An anonymous, cross-sectional survey with a web-based questionnaire was conducted. The survey questionnaire was developed according to clinical experience and current foot care recommendations. State registered podiatrists practising in the state of NSW were invited to participate. The survey link was distributed initially via email to members of the Australian Podiatry Association (NSW), and distributed further through snowballing techniques using professional networks. Data was analysed to assess significant associations between adherence to clinical practice guidelines, and private/public podiatry practices. Results 86 podiatrists participated in the survey (78% from private practice, 22% from public practice). Respondents largely did not adhere to formal guidelines to manage their patients (88%). Only one respondent offered a dedicated service for patients with RA. Respondents indicated that the primary mode of accessing podiatry was by self-referral (68%). Significant variation was observed regarding access to disease and foot specific assessments and treatment strategies. Assessment methods such as administration of patient reported outcome measures, vascular and neurological assessments were not conducted by all respondents. Similarly, routine foot care strategies such as prescription of foot orthoses, foot health advice and footwear were not employed by all respondents. Conclusions The results identified issues in foot care provision which should be explored through further research. Foot care provision in NSW does not appear to meet the current recommended standards for the management of foot problems in people who have RA. Improvements to foot care could be undertaken in terms of providing better access to examination techniques and treatment strategies that are recommended by evidence based treatment paradigms. PMID:23972081

Inhibition of intimal thickening after vascular injury with a cocktail of vascular endothelial growth factor and cyclic Arg-Gly-Asp peptide.

PubMed

Li, Yue; McRobb, Lucinda S; Khachigian, Levon M

2016-10-01

Percutaneous coronary intervention is widely used for the treatment of coronary artery disease; however, significant challenges such as restenosis remain. Key to solving these problems is to inhibit smooth muscle cell activation while enhancing re-endothelialization. Early growth response-1 (Egr-1) is a transcription factor that regulates vascular smooth muscle cell (SMC) proliferation and migration through its control of an array of downstream genes. A "cocktail" of vascular endothelial growth factor (VEGF)-A, VEGF-D and cyclic RGD was tested for its ability to inhibit neointima formation and accelerate re-endothelialization following balloon injury to carotid arteries of rats. In vitro, the cocktail stimulated endothelial cell growth yet inhibited smooth muscle cell growth. In vivo, cocktail-treated injured arteries exhibited reduced intimal thickening by >50% (P<0.05). It increased both re-endothelialization and endothelial nitric oxide synthase (NOS) expression. Cocktail reduced Egr-1 expression, an effect blocked by the NOS inhibitor L-N(G)-nitroarginine methyl ester (L-NAME) that also prevented cocktail inhibition of neointima inhibition. This combination may potentially be useful for the treatment of restenosis with concomitant stimulation of revascularization. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Near-infrared spectroscopic assessment of oxygen delivery to free flaps on monkeys following vascular occlusions and inhalation of pure oxygen

NASA Astrophysics Data System (ADS)

Tian, Fenghua; Ding, Haishu; Cai, Zhigang; Wang, Guangzhi; Zhao, Fuyun

2002-04-01

In recent studies, near-infrared spectroscopy (NIRS) has been considered as a potentially ideal noninvasive technique for the postoperative monitoring of plastic surgery. In this study, free flaps were raised on rhesus monkeys' forearms and oxygen delivery to these flaps was monitored following vascular occlusions and inhalation of pure oxygen. Optical fibers were adopted in the probe of the oximeter so that the detection could be performed in reflectance mode. The distance between emitter and detector can be adjusted easily to achieve the best efficacy. Different and repeatable patterns of changes were measured following vascular occlusions (arterial occlusion, venous occlusion and total occlusion) on flaps. It is clear that the near-infrared spectroscopy is capable of postoperatively monitoring vascular problems in flaps. NIRS showed high sensitivity to detect the dynamic changes in flaps induced by inhalation of pure oxygen in this study. The experimental results indicated that it was potential to assess tissue viability utilizing the dynamic changes induced by a noninvasive stimulation. It may be a new assessing method that is rapid, little influenced by other factors and brings less discomfort to patients.

Simulated hypogravity impairs the angiogenic response of endothelium by up-regulating apoptotic signals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morbidelli, Lucia; Monici, Monica; Marziliano, Nicola

Health hazards in astronauts are represented by cardiovascular problems and impaired bone healing. These disturbances are characterized by a common event, the loss of function by vascular endothelium, leading to impaired angiogenesis. We investigated whether the exposure of cultured endothelial cells to hypogravity condition could affect their behaviour in terms of functional activity, biochemical responses, morphology, and gene expression. Simulated hypogravity conditions for 72 h produced a reduction of cell number. Genomic analysis of endothelial cells exposed to hypogravity revealed that proapoptotic signals increased, while antiapoptotic and proliferation/survival genes were down-regulated by modelled low gravity. Activation of apoptosis was accompaniedmore » by morphological changes with mitochondrial disassembly and organelles/cytoplasmic NAD(P)H redistribution, as evidenced by autofluorescence analysis. In this condition cells were not able to respond to angiogenic stimuli in terms of migration and proliferation. Our study documents functional, morphological, and transcription alterations in vascular endothelium exposed to simulated low gravity conditions, thus providing insights on the occurrence of vascular tissue dysregulation in crewmen during prolonged space flights. Moreover, the alteration of vascular endothelium can intervene as a concause in other systemic effects, like bone remodelling, observed in weightlessness.« less

A catheter-related bloodstream infection caused by Chryseobacterium indologenes successfully treated with antibiotic-lock rescue therapy.

PubMed

Corbella, Marta; Brandolini, Micaela; Cambieri, Patrizia; Decembrino, Nunzia; Pagani, Michele; Bottazzi, Andrea; Muzzi, Alba; Zecca, Marco; Mariani, Bianca; Marone, Piero

2017-07-01

We report the case of a catheter-related bloodstream infection caused by Chryseobacterium indologenes, an uncommon and multi-resistant pathogen, in a pediatric patient with a long-term vascular access device placed for chemotherapy treatment. The infection was successfully treated with ciprofloxacin antibiotic-lock therapy. This is the first report on successful salvage of a long-term device colonized by multi-resistant Chryseobacterium indologenes.

Clinical use of closed-system safety peripheral intravenous cannulas.

PubMed

Barton, Andrew

2018-04-26

Peripheral intravenous (IV) cannulas are the quickest and most effective way of gaining venous vascular access and administering IV therapy. Closed-system peripheral IV cannulas have been shown to be safe and more reliable than open, non-valved peripheral cannulas in clinical practice. This article introduces the Smiths Medical DeltaVen closed-system peripheral IV cannula and includes three case studies describing its use in clinical practice and associated patient outcomes.

Differences between Roma and non-Roma in how social support from family and friends helps to overcome health care accessibility problems.

PubMed

Bobakova, Daniela; Dankulincova Veselska, Zuzana; Babinska, Ingrid; Klein, Daniel; Madarasova Geckova, Andrea; Cislakova, Lydia

2015-04-14

Roma are the most deprived ethnic minority in Slovakia, suffering from discrimination, poverty and social exclusion. Problematic access to good quality health care as result of institutional and interpersonal discrimination affects their health; therefore, factors which affect health care accessibility of Roma are of high importance for public health and policy makers. The aim of this study was to explore the association between health care accessibility problems and ethnicity and how different levels of social support from family and friends affect this association. We used data from the cross-sectional HepaMeta study conducted in 2011 in Slovakia. The final sample comprised 452 Roma (mean age = 34.7; 35.2% men) and 403 (mean age = 33.5; 45.9% men) non-Roma respondents. Roma in comparison with non-Roma have a more than 3-times higher chance of reporting health care accessibility problems. Social support from family and friends significantly decreases the likelihood of reporting health care accessibility problems in both Roma and non-Roma, while the family seems to be the more important factor. The worse access to health care of Roma living in so-called settlements seems to be partially mediated by social support. Interventions should focus on Roma health mediators and community workers who can identify influential individuals who are able to change a community's fear and distrust and persuade and teach Roma to seek and appropriately use health care services.

Contextual Uncertainties, Human Mobility, and Perceived Food Environment: The Uncertain Geographic Context Problem in Food Access Research.

PubMed

Chen, Xiang; Kwan, Mei-Po

2015-09-01

We examined the uncertainty of the contextual influences on food access through an analytic framework of the uncertain geographic context problem (UGCoP). We first examined the compounding effects of two kinds of spatiotemporal uncertainties on people's everyday efforts to procure food and then outlined three key dimensions (food access in real time, temporality of the food environment, and perceived nutrition environment) in which research on food access must improve to better represent the contributing environmental influences that operate at the individual level. Guidelines to address the UGCoP in future food access research are provided to account for the multidimensional influences of the food environment on dietary behaviors.

Impairment of vascularization of the surface covering epithelium induces ischemia and promotes malignization: a new hypothesis of a possible mechanism of cancer pathogenesis.

PubMed

Karseladze, A I

2015-06-01

To study the peculiarities of vascularization at the stromal-epithelial interface in different types of epithelia and their alterations in precancerous lesions. Peritumoral tissues of 310 patients, tissues of 180 healthy persons and of 50 human embryos and fetuses were used. Traditional histological as well as immunohistochemical methods have been used. The study reveals that the occurrence of blood capillaries in surface squamous epithelium is an ordinary event, both in healthy persons and in peritumoral regions of the patients with squamous cell carcinoma. Glandular epithelial coverings, as well as transitional epithelium, do not contain blood vessels. In squamous epithelium, only basal cells are in contact with the membrane and underlying stroma, the cells of the upper layer receiving nutrients through diffusion. Thus, the cells of squamous epithelium are more vulnerable to blood deficiency, since for instance in the pseudo-multilayered respiratory epithelium each cell is attached directly to the basal membrane and has more ample access to the blood supply. Metaplastic squamous epithelium has a markedly reduced vascularization and seems to be more sensitive to carcinogenic stimuli. High-grade dysplastic squamous epithelium and carcinoma in situ do not contain blood vessels. The process of redistribution of vascular network occurring at the interface of epithelial-stromal frontier plays an important role in maintaining the adequate metabolism of cells including those of epithelial covering. Impairment of this mechanism most probably promotes precancerous alterations.

Contrast imaging in mouse embryos using high-frequency ultrasound.

PubMed

Denbeigh, Janet M; Nixon, Brian A; Puri, Mira C; Foster, F Stuart

2015-03-04

Ultrasound contrast-enhanced imaging can convey essential quantitative information regarding tissue vascularity and perfusion and, in targeted applications, facilitate the detection and measure of vascular biomarkers at the molecular level. Within the mouse embryo, this noninvasive technique may be used to uncover basic mechanisms underlying vascular development in the early mouse circulatory system and in genetic models of cardiovascular disease. The mouse embryo also presents as an excellent model for studying the adhesion of microbubbles to angiogenic targets (including vascular endothelial growth factor receptor 2 (VEGFR2) or αvβ3) and for assessing the quantitative nature of molecular ultrasound. We therefore developed a method to introduce ultrasound contrast agents into the vasculature of living, isolated embryos. This allows freedom in terms of injection control and positioning, reproducibility of the imaging plane without obstruction and motion, and simplified image analysis and quantification. Late gestational stage (embryonic day (E)16.6 and E17.5) murine embryos were isolated from the uterus, gently exteriorized from the yolk sac and microbubble contrast agents were injected into veins accessible on the chorionic surface of the placental disc. Nonlinear contrast ultrasound imaging was then employed to collect a number of basic perfusion parameters (peak enhancement, wash-in rate and time to peak) and quantify targeted microbubble binding in an endoglin mouse model. We show the successful circulation of microbubbles within living embryos and the utility of this approach in characterizing embryonic vasculature and microbubble behavior.

Coating of Dacron vascular grafts with an ionic polyurethane: a novel sealant with protein binding properties.

PubMed

Phaneuf, M D; Dempsey, D J; Bide, M J; Quist, W C; LoGerfo, F W

2001-03-01

The purpose of this study was to develop a novel sealant that would seal prosthetic vascular graft interstices and be accessible for protein binding. Crimped knitted Dacron vascular grafts were cleaned (CNTRL) and hydrolyzed in boiling sodium hydroxide (HYD). These HYD grafts were sealed using an 11% solids solution of a polyether-based urethane with carboxylic acid groups (PEU-D) via a novel technique that employs both trans-wall and luminal perfusion. Carboxylic acid content, determined via methylene blue dye uptake, was 2.3- and 4.2-fold greater in PEU-D segments (1.0+/-0.27 nmol/mg) as compared to HYD and CNTRL segments, respectively. Water permeation through PEU-D graft (1.1+/-2 ml/cm2 min(-1)) was comparable to collagen-impregnated Dacron (9.8+/-10 ml/cm2 min(-1)). Non-specific 125I-albumin (125I-Alb) binding to PEU-D segments (18+/-3 ng/mg) was significantly lower than HYD and CNTRL segments. 125I-Alb linkage to PEU-D using the crosslinker EDC resulted in 5.7-fold greater binding (103+/-2 ng/mg) than non-specific PEU-D controls. However, covalent linkage of 125I-Alb to PEU-D was 4.9- and 5.9-fold less than CNTRL and HYD segments with EDC, respectively. Thus, ionic polyurethane can be applied to a pre-formed vascular graft, seal the interstices and create "anchor" sites for protein attachment.

Down Syndrome: A Cardiovascular Perspective

ERIC Educational Resources Information Center

Vis, J. C.; Duffels, M. G. J.; Winter, M. M.; Weijerman, M. E.; Cobben, J. M.; Huisman, S. A.; Mulder, B. J. M.

2009-01-01

This review focuses on the heart and vascular system in patients with Down syndrome. A clear knowledge on the wide spectrum of various abnormalities associated with this syndrome is essential for skillful management of cardiac problems in patients with Down syndrome. Epidemiology of congenital heart defects, cardiovascular aspects and…

Medical School Education in Hypertension Management: A National Survey.

ERIC Educational Resources Information Center

Moser, Marvin; And Others

1983-01-01

The management of patients with primary hypertension remains a significant problem for the medical profession. In spite of this, specific programs for education in hypertensive vascular disease have been poorly organized. A survey to determine the level of training in this discipline is discussed. (MLW)

Gaming machine addiction: the role of avoidance, accessibility and social support.

PubMed

Thomas, Anna C; Allen, Felicity L; Phillips, James; Karantzas, Gery

2011-12-01

Commonality in etiology and clinical expression plus high comorbidity between pathological gambling and substance use disorders suggest common underlying motives. It is important to understand common motivators and differentiating factors. An overarching framework of addiction was used to examine predictors of problem gambling in current electronic gaming machine (EGM) gamblers. Path analysis was used to examine the relationships between antecedent factors (stressors, coping habits, social support), gambling motivations (avoidance, accessibility, social) and gambling behavior. Three hundred and forty seven (229 females: M = 29.20 years, SD = 14.93; 118 males: M = 29.64 years, SD = 12.49) people participated. Consistent with stress, coping and addiction theory, situational life stressors and general avoidance coping were positively related to avoidance-motivated gambling. In turn, avoidance-motivated gambling was positively related to EGM gambling frequency and problems. Consistent with exposure theory, life stressors were positively related to accessibility-motivated gambling, and accessibility-motivated gambling was positively related to EGM gambling frequency and gambling problems. These findings are consistent with other addiction research and suggest avoidance-motivated gambling is part of a more generalized pattern of avoidance coping with relative accessibility to EGM gambling explaining its choice as a method of avoidance. Findings also showed social support acted as a direct protective factor in relation to gambling frequency and problems and indirectly via avoidance and accessibility gambling motivations. Finally, life stressors were positively related to socially motivated gambling but this motivation was not related to either social support or gambling behavior suggesting it has little direct influence on gambling problems.