Central venous catheter infection-related glomerulonephritis under long-term parenteral nutrition: a report of two cases.

PubMed

Okada, Mari; Sato, Mai; Ogura, Masao; Kamei, Koichi; Matsuoka, Kentaro; Ito, Shuichi

2016-03-31

Advances in long-term parenteral nutrition via indwelling central venous catheter have improved the quality of life and mortality in patients with life-threatening gastrointestinal diseases complicated with severely impaired absorption. However, infection to central venous catheter is still a common and critical complication for such patients. We encountered two patients under long-term parenteral nutrition who developed glomerulonephritis associated with central venous catheter infection. Persistent bacterial infection in indwelling medical devices placed in the blood-stream such as a ventricular-atrial shunt is known to cause glomerulonephritis, a condition termed shunt nephritis. We reported the clinical manifestations, treatment and their pathological findings in the two patients with glomerulonephritis associated with central venous catheter infection. Both patients suffered from megacystis microcolon intestinal hypoperistalsis syndrome, a form of pseudo-Hirschsprung's disease. They had been receiving home parenteral nutrition via central venous catheter because of severe malabsorption. They presented proteinuria, hematuria, hypocomplementemia and positive PR3-antineutrophilic cytoplasmic antibody accompanied by Staphylococcus epidermidis infection in the central venous catheter. Their renal biopsy revealed membranoproliferative glomerulonephritis with positive C3 deposition. One of them recovered completely following the removal of catheter and administration of antibiotics, while another did not respond to the treatments. We then treated her with methylprednisolone pulse therapy followed by prednisolone. She responded well, and achieved complete remission. As central venous catheter infection-related glomerulonephritis has a similar etiology to shunt nephritis, removal of the catheter and administration of antibiotics is fundamental to the treatment. If a patient is resistant to such conventional therapy, additional steroid and/or immunosuppressive agent

Changing concepts in long-term central venous access: catheter selection and cost savings.

PubMed

Horattas, M C; Trupiano, J; Hopkins, S; Pasini, D; Martino, C; Murty, A

2001-02-01

Long-term central venous access is becoming an increasingly important component of health care today. Long-term central venous access is important therapeutically for a multitude of reasons, including the administration of chemotherapy, antibiotics, and total parenteral nutrition. Central venous access can be established in a variety of ways varying from catheters inserted at the bedside to surgically placed ports. Furthermore, in an effort to control costs, many traditionally inpatient therapies have moved to an outpatient setting. This raises many questions regarding catheter selection. Which catheter will result in the best outcome at the least cost? It has become apparent in our hospital that traditionally placed surgical catheters (ie, Hickmans and central venous ports) may no longer be the only options. The objective of this study was to explore the various modalities for establishing central venous access comparing indications, costs, and complications to guide the clinician in choosing the appropriate catheter with the best outcome at the least cost. We evaluated our institution's central venous catheter use during a 3-year period from 1995 through 1997. Data was obtained retrospectively through chart review. In addition to demographic data, specific information regarding catheter type, placement technique, indications, complications, and catheter history were recorded. Cost data were obtained from several departments including surgery, radiology, nursing, anesthesia, pharmacy, and the hospital purchasing department. During a 30-month period, 684 attempted central venous catheter insertions were identified, including 126 surgically placed central venous catheters, 264 peripherally inserted central catheters by the nursing service, and 294 radiologically inserted peripheral ports. Overall complications were rare but tended to be more severe in the surgical group. Relative cost differences between the groups were significant. Charges for peripherally inserted

The Impact of Tunneled Catheters for Ascites and Peritoneal Carcinomatosis on Patient Rehospitalizations

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

Qu, Chuanxing; Xing, Minzhi; Ghodadra, Anish

PurposeThe aim of the study is to assess patient outcomes, complications, impact on rehospitalizations, and healthcare costs in patients with malignant ascites treated with tunneled catheters.Materials and MethodsA total of 84 patients with malignant ascites (mean age, 60 years) were treated with tunneled catheters. Patients with peritoneal carcinomatosis and malignant ascites treated with tunneled drain catheter placement over a 3-year period were studied. Overall survival from the time of ascites and catheter placement were stratified by primary cancer and analyzed using the Kaplan–Meier method. Complications were graded by the Common Terminology Criteria for Adverse Events v3.0 (CTCAE). The differences between pre-more » and post-catheter admissions, hospitalizations, and Emergency Department (ED) visits, as well as related inpatient expenses were compared using paired t tests.ResultsThere were no significant differences in gender, age, or race between different primary cancer subgroups. One patient (1 %) developed bleeding (CTCAE-2). Four patients (5 %) developed local cellulitis (CTCAE-2). Three patients (4 %) had prolonged hospital stay (between 7 and 10 days) to manage ascites-related complications such as abdominal distention, discomfort, or pain. Comparison between pre- and post-catheter hospitalizations showed significantly lower admissions (−1.4/month, p < 0.001), hospital stays (−4.2/month, p = 0.003), and ED visits (−0.9/month, p = 0.002). The pre- and post-catheter treatment health care cost was estimated using MS-DRG IPPS payment system and it demonstrated significant cost savings from decreased inpatient admissions in post-treatment period (−$9535/month, p < 0.001).ConclusionsTunneled catheter treatment of malignant ascites is safe, feasible, well tolerated, and cost effective. Tunneled catheter treatment may play an important role in improving patients’ quality of life and outcomes while controlling health care

Changes observed in urine microbiology following replacement of long-term urinary catheters: need to modify UTI guidelines in the UK?

PubMed

Batura, Deepak; Gopal Rao, G; Foran, Marion; Brempong, Fatmata

2018-01-01

Bacteria adherent to long-term urinary catheters (LTUC) may give misleading urine culture results. Guidelines in the USA recommend changing LTUC before urine collection to diagnose UTI and before commencing appropriate antimicrobial treatment. However, in the UK there is no such guidance. In this study, we evaluated differences in urine cultures before and after changing LTUC. In a prospective study in a UK urology department, we made a quantitative and qualitative comparison between paired urines collected before and after catheter change in patients with LTUC. We measured culture growth on a four-point ordinal scale as nil, scanty (< 10 7  cfu/L), moderate (10 7 -10 8  cfu/L) or heavy (> 10 8  cfu/L) and recorded the range of bacterial species isolated. Statistical analysis was by Wilcoxon matched-pairs test. Sixty-six patients (55 males, 11 females) took part in the study. Urines with no growth increased from 7/66 (11%) before change of catheter to 21/66(32%) after change of catheter. Cultures reported as heavy growth (> 10 8  cfu/L) reduced from 48/66 (73%) to 25/66 (38%) after catheter change (p < 0.001). Except for Pseudomonas spp., other organisms were isolated less frequently after catheter change. No Proteus spp. was isolated after catheter change. This study confirms that failure to change long-term catheters before collecting urine for culture may give misleading results. In the interest of accurate diagnosis and antimicrobial stewardship, UK guidelines should recommend changing long-term urinary catheters before collection of urine for culture.

Cigarette smoking causes a worse long-term outcome in persistent atrial fibrillation following catheter ablation.

PubMed

Cheng, Wen-Han; Lo, Li-Wei; Lin, Yenn-Jiang; Chang, Shih-Lin; Hu, Yu-Feng; Hung, Yuan; Chung, Fa-Po; Chang, Ting-Yung; Huang, Ting-Chung; Yamada, Shinya; Salim, Simon; Te, Abigail Louise D; Liao, Jo-Nan; Tuan, Ta-Chuan; Chao, Tze-Fan; Tsai, Tseng-Ying; Liu, Shin-Huei; Chen, Shih-Ann

2018-02-09

Cigarette smoking contributes to the development of atrial fibrosis via nicotine. The impact of smoking on ablation results in persistent atrial fibrillation (AF) is unknown. We aimed to investigate the triggers and long-term outcome between smokers and nonsmokers in the patients with persistent AF after catheter ablation. This study included 201 (177 males, 53 ± 10 years old) patients who received index catheter ablation, including pulmonary vein isolation (PVI) and complex fractionated atrial electrograms (CFAEs) ablation for persistent AF, retrospectively. Electrophysiological characteristics at the index procedure and long-term outcome were investigated to determine the differences between smokers and nonsmokers. Baseline characteristics were similar between two groups. Pulmonary vein (PV) triggers were found in all patients in the two groups. There was a higher incidence of nonpulmonary vein (NPV) triggers in smokers than in nonsmokers (61% vs. 31%, P < 0.05). There were no differences of the long-term ablation outcomes between smokers and nonsmokers in Kaplan-Meier analysis. Smokers with PV plus right atrial NPV (RA-NPV) triggers had a higher incidence of recurrence (log-rank P < 0.05) than those without RA-NPV triggers, but not in nonsmokers, after a mean follow-up of 31 ± 25 months. Smoking increases the incidence of NPV triggers in patients with persistent AF. Smokers who have RA-NPV triggers during index procedure do have a worse outcome after catheter ablation, indicating the harmful effects of nicotine to right atrium. © 2018 Wiley Periodicals, Inc.

Long-term use of nerve block catheters in paediatric patients with cancer related pathologic fractures

PubMed Central

BURGOYNE, L. L.; PEREIRAS, L. A.; BERTANI, L. A.; KADDOUM, R. N.; NEEL, M.; FAUGHNAN, L. G.; ANGHELESCU, D. L.

2013-01-01

SUMMARY We report three cases of children with osteosarcoma and pathologic fractures treated with long-term continuous nerve blocks for preoperative pain control. One patient with a left distal femoral diaphysis fracture had a femoral continuous nerve block catheter for 41 days without complications. Another with a fractured left proximal femoral shaft had three femoral continuous nerve block catheters for 33, 26 and 22 days respectively. The third patient, whose right proximal humerus was fractured, had a brachial plexus continuous nerve block catheter for 36 days without complication. In our experience, prolonged use of continuous nerve block is safe and effective in children with pathologic fractures for preoperative pain control. PMID:22813501

Do catheter washouts extend patency time in long-term indwelling urethral catheters? A randomized controlled trial of acidic washout solution, normal saline washout, or standard care.

PubMed

Moore, Katherine N; Hunter, Kathleen F; McGinnis, Rosemary; Bacsu, Chasta; Fader, Mandy; Gray, Mikel; Getliffe, Kathy; Chobanuk, Janice; Puttagunta, Lakshmi; Voaklander, Donald C

2009-01-01

Blockage of long-term indwelling catheters with mineral deposit is an ongoing management issue, but evidence on optimal management is lacking. Our purpose was to examine whether catheter washouts prevent or reduce catheter blockage. A multisite randomized controlled trial. Adults with long-term indwelling catheters that required changing every 3 weeks or less, living in the community, and requiring supportive or continuing care were recruited. Participants were randomly assigned to 1 of 3 groups: control (usual care, no washout), saline washout, or commercially available acidic washout solution (Contisol Maelor Pharmaceuticals Ltd, Wrexham, UK). At baseline visit, the catheter was changed and participants were followed weekly for 8 weeks, with checks for catheter patency and urine pH. Participants randomized to saline or commercial solution had a weekly washout with the appropriate solution. Endpoints were 8 weeks (completion data), 3 or more catheter changes in the 8-week period, or symptomatic urinary tract infection (UTI) requiring antibiotics. The study hypothesis was that catheter life would be extended by 25% in the commercial solution group. It was not possible to blind participants or research nurses to washout versus no intervention, but participants in the saline and washout solution groups were blinded to solution type. One hundred twelve potential participants were screened; 73 were enrolled, randomized, and included in the final analysis. Of these, 53 completed the full 8 weeks of data collection; 16 terminated early because of 3 catheter changes or self-reported 'UTI'. Other reasons for termination were hematuria, latex sensitivity, deceased/severe illness, or personal choice. Analysis of variance was used to analyze mean differences on demographic variables and mean number of weeks in study. Kaplan-Meier survival curve analysis showed no statistical difference between the groups in time to first catheter change. At this time, the evidence is

Long-term urethral catheterisation.

PubMed

Turner, Bruce; Dickens, Nicola

This article discusses long-term urethral catheterisation, focusing on the relevant anatomy and physiology, indications for the procedure, catheter selection and catheter care. It is important that nurses have a good working knowledge of long-term catheterisation as the need for this intervention will increase with the rise in chronic health conditions and the ageing population.

Evaluation of healing and external tunnel histology of silver-coated peritoneal catheters in rats.

PubMed

Kathuria, P; Moore, H L; Mehrotra, R; Prowant, B F; Khanna, R; Twardowski, Z J

1996-01-01

A previous study showed that silver-coating peritoneal catheters tended to decrease the incidence of early exit-site infections in rats. This study was designed to further evaluate the healing, biocompatability, and external tunnel morphology of standard and silver-coated catheters. Catheters were coated with silver by an ion beam-assisted process. Fourteen male Sprague-Dawley rats underwent implantation of either a standard or silver-coated double-cuff peritoneal catheter. Weekly observation and photographs documented exit-site characteristics. Erythema, exudate, loose fit, and poor hair growth were evidence of an inflamed exit. Overt infection was indicated by the presence of three or more of the following: erythema, purulent exudate, exuberant granulation tissue, loose fit, and poor hair growth. Animals were sacrificed at six weeks, and catheters were removed and processed for histology of the external tunnel. Multiple measurements were taken using a Filar eyepiece, and data were expressed as a mean of several readings. Inflammation, vascularity, and fibrosis were judged semiquantitatively. At the end of six weeks, six of the seven exits of the silver catheters showed excellent healing, while one exit site had signs of excessive inflammation. Four of the exit sites of the standard catheters healed well, two were inflamed, and one was overtly infected. The sinus tract of the standard and silver catheters had similar characteristics: keratinized and nonkeratinized epithelium lined the external part of the sinus tract and merged into granulation tissue. A fibrous sheath was noted in some sinus tracts between the granulation tissue and the cuff. The cuff evoked a foreign body reaction, with fibrosis, multiple giant cells, and vascularization. Poorly healing or infected sinus tracts had highly vascular granulation tissue with overlying exudate. The cuff of these catheters had marked inflammation and scanty giant cells, although collagen bundle thickness was similar

Short-Term Plasticity and Long-Term Potentiation in Magnetic Tunnel Junctions: Towards Volatile Synapses

NASA Astrophysics Data System (ADS)

Sengupta, Abhronil; Roy, Kaushik

2016-02-01

Synaptic memory is considered to be the main element responsible for learning and cognition in humans. Although traditionally nonvolatile long-term plasticity changes are implemented in nanoelectronic synapses for neuromorphic applications, recent studies in neuroscience reveal that biological synapses undergo metastable volatile strengthening followed by a long-term strengthening provided that the frequency of the input stimulus is sufficiently high. Such "memory strengthening" and "memory decay" functionalities can potentially lead to adaptive neuromorphic architectures. In this paper, we demonstrate the close resemblance of the magnetization dynamics of a magnetic tunnel junction (MTJ) to short-term plasticity and long-term potentiation observed in biological synapses. We illustrate that, in addition to the magnitude and duration of the input stimulus, the frequency of the stimulus plays a critical role in determining long-term potentiation of the MTJ. Such MTJ synaptic memory arrays can be utilized to create compact, ultrafast, and low-power intelligent neural systems.

Reduction of exit-site infections of tunnelled intravascular catheters among neutropenic patients by sustained-release chlorhexidine dressings: results from a prospective randomized controlled trial.

PubMed

Chambers, S T; Sanders, J; Patton, W N; Ganly, P; Birch, M; Crump, J A; Spearing, R L

2005-09-01

Exit-site and tunnel infections of tunnelled central intravascular catheters are a frequent source of morbidity among neutropenic patients and may necessitate catheter removal. They require antimicrobial therapy that increases healthcare costs and is associated with adverse drug reactions. A prospective randomized clinical trial was conducted among adult patients undergoing chemotherapy in a haematology unit. Tunnelled intravascular catheters were randomized to receive the control of a standard dressing regimen as recommended by the British Committee for Standards in Haematology, or to receive the intervention of a sustained-release chlorhexidine dressing. Follow-up data were available in 112 of 114 tunnelled intravascular catheters which were randomized. Exit-site or combined exit-site/tunnel infections occurred in 23 (43%) of 54 catheters in the control group, and five (9%) of 58 catheters in the intervention group [odds ratio (OR) for intervention group compared with control group =0.13, 95% confidence intervals (CI) 0.04-0.37, P<0.001]. More tunnelled intravascular catheters were prematurely removed from the control group than the intervention group for documented infections [20/54 (37%) vs 6/58 (10%), OR=0.20, 95%CI 0.53-0.07]. However, there was no difference in the numbers of tunnelled intravascular catheters removed for all proven and suspected intravascular catheter-related infections [21/54 (39%) vs 19/58 (33%)], or in the time to removal of catheters for any reason other than death or end of treatment for underlying disease. Thus chlorhexidine dressings reduced the incidence of exit-site/tunnel infections of indwelling tunnelled intravascular catheters without prolonging catheter survival in neutropenic patients, and could be considered as part of the routine management of indwelling tunnelled intravascular catheters among neutropenic patients.

[Prevalence of stenosis and thrombosis of central veins in hemodialysis after a tunneled jugular catheter].

PubMed

Jean, G; Vanel, T; Chazot, C; Charra, B; Terrat, J C; Hurot, J M

2001-01-01

Central venous stenosis (ST) and thrombosis (TB) related to catheter (KT) had been reported mostly for the subclavian vein. We performed a systematic cavographic study to evaluate the prevalence of these complications in 51 hemodialysis patients with present or previous history of tunneled internal jugular catheter. Each of them had used one or several KT (1.8 +/- 1.4 KT) for a mean 28 +/- 26 month cumulative time (i.e. 43,584 days total exposure time). Fifty percent of the KT were PermCath Quinton and 50% were Twincath (uncuffed) or CS 100 (cuffed) Medcomp. Twenty-seven had no ST (53%, group I), 24 had one or several significant ST (47%, group II) of superior Vena Cava (SVC, n = 4), inferior Vena Cava (IVC, n = 1), Brachio-cephalic Vein (BCV, n = 5) and subclavian vein (SC, n = 10), or a TB of SVC (n = 1), IVC (n = 3), BCV (n = 3), SC (n = 2). This accounts for an incidence of 0.55 ST or TB/1000 patient-days. Five of the twelve subclavian ST and TB had no history of previous subclavian catheter. Comparison between the two groups showed no differences according to age, time on dialysis, diabetes, hematocrit, CRP, cumulative time with catheter, catheter-related infections, type of catheter and anticoagulant treatment. IVC catheter tip's position is an important risk factor for TB and ST (4/6). Twelve group II patients had ST or TB-related symptoms, with a functional AV fistula in 9 cases. Eleven patients underwent repeated percutaneous angioplasty with 4 additional Wallstents and in 2 cases an AV fistula need to be closed. Central venous ST and TB after a jugular KT is extremely frequent, mostly without any symptoms. Consequences on peripheral or central vascular access, cost and poor long-term patency rate of angioplasty are of major importance. These results incite us to further reduce the catheter use in dialysis patients.

Hemodialysis tunneled central venous catheters: five-year outcome analysis.

PubMed

Mandolfo, Salvatore; Acconcia, Pasqualina; Bucci, Raffaella; Corradi, Bruno; Farina, Marco; Rizzo, Maria Antonietta; Stucchi, Andrea

2014-01-01

Tunneled central venous catheters (tCVCs) are considered inferior to arteriovenous fistulas (AVFs) and grafts in all nephrology guidelines. However, they are being increasingly used as hemodialysis vascular access. The purpose of this study was to document the natural history of tCVCs and determine the rate and type of catheter replacement. This was a prospective study of 141 patients who underwent hemodialysis with tCVCs between January 2008 and December 2012. The patients used 154 tCVCs. Standard protocols about management of tCVCs, according to European Renal Best Practice, were well established. All catheters were inserted in the internal jugular vein. Criteria for catheter removal were persistent bloodstream infection, detection of an outbreak of catheter-related bloodstream (CRBS) infections, or catheter dysfunction. Event rates were calculated per 1,000 catheter days; tCVC cumulative survival was estimated by Kaplan-Meier analysis. Catheter replacement occurred in 15 patients (0.29 per 1,000 days); catheter dysfunction was the main cause of replacement (0.18 per 1,000 days), typically within 12 months of surgical insertion. A total of 53 CRBS events in 36 patients were identified (0.82 per 1,000 days); 17 organisms, most commonly Gram-positive pathogens, were isolated; 87% of CVC infections were treated by systemic antibiotics associated with lock therapy. tCVC cumulative survival was 91% at 1 year, 88% at 2 years and 85% at 4 years. Our data show a high survival rate of tCVCs in hemodialysis patients, with low incidence of catheter dysfunction and CRBS events. These data justify tCVC use for hemodialysis vascular access, also as first choice, especially in patients with exhausted peripheral access and limited life expectancy.

[Infections on catheters in hemodialysis: Temporal fluctuations of the infectious risk].

PubMed

Izoard, S; Ayzac, L; Meynier, J; Seghezzi, J-C; Jolibois, B; Tolani, M L

2017-11-01

International guidelines recommend to limit the long-term use of central-veinous catheters in patients undergoing hemodialysis, because they expose the patient to a higher infectious risk than the fistulas. However, for some patients with comorbidity, switching to a permanent vascular access is not possible. In such case, the catheter is used for a longer period. It seems therefore important to study the influence of a prolonged duration of catheterization on infectious complications. The temporal fluctuation profile of the infectious risk is poorly studied in the literature and the results published may be contradictory. This multicentric prospective study included 1053 incident tunneled catheters. Multivariate logistic regression was used to identify significant risk factors of infection. An infection-free survival analysis was performed afterwards to estimate the variation of the instantaneous infectious risk during catheterization. The major risks factors of infections on tunneled catheters were: previous Staphylococcus aureus infection (aOR=1.95 [1.16-3.27]; P=0.012), diabetes (aOR=1.67 [1.16-2.41]; P=0.006), and long duration of catheterization (0-3months vs.≥24months: aOR=2.42 [1.34-4.36]; P=0.003). The survival analysis showed a higher risk of infections of tunneled catheters during the first months after placement. Risk declines over time. The fluctuation profile of the infectious risk show that preventive precautions should target the first months of catheterization. Copyright © 2017 Société francophone de néphrologie, dialyse et transplantation. Published by Elsevier Masson SAS. All rights reserved.

Problems of long-term spinal opioid treatment in advanced cancer patients.

PubMed

Mercadante, S

1999-01-01

Epidural and intrathecal techniques are well established techniques in cancer pain. However, several questions remain unresolved. The several problems of long-term spinal opioid treatment in advance cancer patients were reviewed. Indications for the use of spinal opioids include patients treated by systemic opioids with effective pain relief but with unacceptable side effects, or unsuccessful treatment with sequential strong opioid drug trials despite escalating doses. Therefore, the previous aggressive treatment with systemic opioids would leave as failures patients with difficult pain syndromes unresponsive to opioids. The choice of external or totally implanted delivery systems is based on different clinical considerations. The use of externalized tunneled intrathecal catheters has not been associated with higher rates of complications and is easier to place and use at home in debilitated patients late in the course of their disease. The intrathecal administration has a lower incidence of catheter occlusion, lower malfunctioning rate, lower dose requirement, and more effective pain control. Due to the lower daily doses and volumes, intrathecal treatment proved to be more suitable for treatment at home by a continuous infusion than the epidural treatment. Advantages of infusion techniques are more evident when using local anesthetics, since intermittent administration of bupivacaine often results in motor paralysis and hemodynamic instability. Morphine is the opioid of choice. An epidural dose of 10% of the systemic dose is often used. However, intrathecal administration of opioids and bupivacaine may substantially improve pain relief in patients unresponsive to high epidural doses of these drugs, Bupivacaine-induced adverse effects, including sensory deficits, motor complaints, signs of autonomic dysfunction or neurotoxicity have been reported to not occur with bupivacaine doses less than 30-60 mg/day. Adjuvant drugs may further improve analgesia. Different

Hemodialysis Tunneled Catheter Noninfectious Complications

PubMed Central

Miller, Lisa M.; MacRae, Jennifer M.; Kiaii, Mercedeh; Clark, Edward; Dipchand, Christine; Kappel, Joanne; Lok, Charmaine; Luscombe, Rick; Moist, Louise; Oliver, Matthew; Pike, Pamela; Hiremath, Swapnil

2016-01-01

Noninfectious hemodialysis catheter complications include catheter dysfunction, catheter-related thrombus, and central vein stenosis. The definitions, causes, and treatment strategies for catheter dysfunction are reviewed below. Catheter-related thrombus is a less common but serious complication of catheters, requiring catheter removal and systemic anticoagulation. In addition, the risk factors, clinical manifestation, and treatment options for central vein stenosis are outlined. PMID:28270922

Central venous catheters: legal issues.

PubMed

Gallieni, Maurizio; Martina, Valentina; Rizzo, Maria Antonietta; Gravellone, Luciana; Mobilia, Francesca; Giordano, Antonino; Cusi, Daniele; Genovese, Umberto

2011-01-01

In dialysis patients, both central venous catheter (CVC) insertion and CVC use during the dialysis procedure pose important legal issues, because of potentially severe, even fatal, complications. The first issue is the decision of the kind of vascular access that should be proposed to patients: an arteriovenous (AV) fistula, a graft, or a CVC. The second issue, when choosing the CVC option, is the choice of CVC: nontunneled versus tunneled. Leaving a temporary nontunneled CVC for a prolonged time increases the risk of complications and could raise a liability issue. Even when choosing a long-term tunneled CVC, nephrologists should systematically explain its potential harms, presenting them as "unsafe for long-term use" unless there is a clear contraindication to an AV native or prosthetic access. Another critical issue is the preparation of a complete, informative, and easy-to-understand consent form. The CVC insertion procedure has many aspects of legal interest, including the choice of CVC, the use of ECG monitoring, the use of ultrasound guidance for cannulation, and the use of fluoroscopy for checking the position of the metal guidewire during the procedure as well as the CVC tip before the end of the procedure. Use of insertion devices and techniques that can prevent complications should obviously be encouraged. Complications of CVC use are mainly thrombosis and infection. These are theoretically expected as pure complications (and not as malpractice effects), but legal issues might relate to inappropriate catheter care (in both the inpatient and outpatient settings) rather than to the event per se. Thus, in the individual case it is indeed very difficult to establish malpractice and liability with a catheter-related infection or thrombosis. In conclusion, we cannot avoid complications completely when using CVCs, but reducing them to a minimum and adopting safe approaches to their insertion and use will reduce legal liability.

Tensile strength decreases and perfusion pressure of 3-holed polyamide epidural catheters increases in long-term epidural infusion.

PubMed

Kim, Pascal; Meyer, Urs; Schüpfer, Guido; Rukwied, Roman; Konrad, Christoph; Gerber, Helmut

2011-01-01

Epidural analgesia is an established method for pain management. The failure rate is 8% to 12% due to technical difficulties (catheter dislocation and/or disconnection; partial or total catheter occlusion) and management. The mechanical properties of the catheters, like tensile strength and flow rate, may also be affected by the analgesic solution and/or the tissue environment. We investigated the tensile strength and perfusion pressure of new (n=20), perioperatively (n=30), and postoperatively (n=73) used epidural catheters (20-gauge, polyamide, closed tip, 3 side holes; Perifix [B. Braun]). To prevent dislocation, epidural catheters were taped (n=5) or fixed by suture (n=68) to the skin. After removal, mechanical properties were assessed by a tensile-testing machine (INSTRON 4500), and perfusion pressure was measured at flow rates of 10, 20, and 40 mL/h. All catheters demonstrated a 2-step force transmission. Initially, a minimal increase of length could be observed at 15 N followed by an elongation of several cm at additional forces (7 N). Breakage occurred in the control group at 23.5±1.5 N compared with 22.4±1.6 N in perioperative and 22.4±1.7 N in postoperative catheters (P<0.05). Duration of catheter use had no effect on tensile strength, whereas perfusion pressure at clinically used flow rates (10 mL/h) increased significantly from 19±1.3 to 44±72 mm Hg during long-term (≥7 days) epidural analgesia (P<0.05, analysis of variance). Fixation by suture had no influence on tensile strength or perfusion pressure. Epidural catheter use significantly increases the perfusion pressure and decreases the tensile strength. Copyright © 2011 by American Society of Regional Anesthesia and Pain Medicine

Microbiology of tunnelled catheter-related infections in a multi-ethnic South-east Asian patient population.

PubMed

Teo, Boon Wee; Sau, Po Yi; Xu, Hui; Ma, Valerie; Vathsala, A; Lee, Evan J C

2011-01-01

Clinical practice guidelines recommend empiric antibiotic therapy for suspected tunnelled haemodialysis catheter-related infections (CRI), and the choice of antibiotics should be adjusted according to the local microbiological profile and antimicrobial sensitivities. We aim to describe the microbiology, antibiotic sensitivities, and clinical outcomes of CRI with tunnelled haemodialysis catheters in a multi-ethnic South-East Asian population. Using a prospective vascular access registry, we identified 99 patients who had catheters removed for suspected or confirmed CRI (50.5% male, mean age 56.9 years) from January 1, 2007, till May 2009. We retrospectively retrieved microbiology, mortality and echocardiography data from the hospital electronic databases. There were 115 removal-unique cultures that yielded 75.7% Gram-positive and 24.3% Gram-negative isolates (15 removals were polymicrobial). Organisms isolated were methicillin-resistant Staphylococcus aureus (MRSA) 28.6%, methicillin-sensitive S. aureus 26.5%, coagulase-negative staphylococci 21.4%, Pseudomonas aeruginosa 10.2%, and others. Out of 8 patients who died, 7 had MRSA. Risk factors associated with mortality were Chinese race (p = 0.03), MRSA infection (p < 0.001), and older age (p < 0.001). Gram-positive isolates accounted for most tunnelled CRI and MRSA was highly associated with death. In sick patients presenting with suspected CRI, the preferred empiric antibiotic regimen should include agents active against both MRSA and P. aeruginosa. Copyright © 2010 S. Karger AG, Basel.

Long-Term Outcome With Catheter Ablation of Ventricular Tachycardia in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy.

PubMed

Santangeli, Pasquale; Zado, Erica S; Supple, Gregory E; Haqqani, Haris M; Garcia, Fermin C; Tschabrunn, Cory M; Callans, David J; Lin, David; Dixit, Sanjay; Hutchinson, Mathew D; Riley, Michael P; Marchlinski, Francis E

2015-12-01

Catheter ablation of ventricular tachycardia (VT) in arrhythmogenic right ventricular cardiomyopathy improves short-term VT-free survival. We sought to determine the long-term outcomes of VT control and need for antiarrhythmic drug therapy after endocardial (ENDO) and adjuvant epicardial (EPI) substrate modification in patients with arrhythmogenic right ventricular cardiomyopathy. We examined 62 consecutive patients with Task Force criteria for arrhythmogenic right ventricular cardiomyopathy referred for VT ablation with a minimum follow-up of 1 year. Catheter ablation was guided by activation/entrainment mapping for tolerated VT and pacemapping/targeting of abnormal substrate for unmappable VT. Adjuvant EPI ablation was performed when recurrent VT or persistent inducibility after ENDO-only ablation. Endocardial plus adjuvant EPI ablation was performed in 39 (63%) patients, including 13 who crossed over to ENDO-EPI after VT recurrence during follow-up, after ENDO-only ablation. Before ablation, 54 of 62 patients failed a mean of 2.4 antiarrhythmic drugs, including amiodarone in 29 (47%) patients. During follow-up of 56±44 months after the last ablation, VT-free survival was 71% with only a single VT episode in additional 9 patients (15%). At last follow-up, 39 (64%) patients were only on β-blockers or no treatment, 21 were on class 1 or 3 antiarrhythmic drugs (11 for atrial arrhythmias), and 2 were on amiodarone as a bridge to heart transplantation. The long-term outcome after ENDO and adjuvant EPI substrate ablation of VT in arrhythmogenic right ventricular cardiomyopathy is good. Most patients have complete VT control without amiodarone therapy and limited need for antiarrhythmic drugs. © 2015 American Heart Association, Inc.

Early catheter removal after radical retropubic prostatectomy: long-term followup.

PubMed

Koch, Michael O; Nayee, Anish H; Sloan, James; Gardner, Thomas; Wahle, Greg R; Bihrle, Richard; Foster, Richard S

2003-06-01

We examine the complication and continence rates with early catheter removal (day 3 or 4) after radical retropubic prostatectomy. A total of 365 patients with localized prostate cancer underwent radical retropubic prostatectomy at Indiana University Hospital with planned urethral catheter removal before discharge home. Low pressure cystograms were performed on postoperative day 3 or 4 to determine if catheter removal was possible. A subset of patients were analyzed using a validated prostate cancer specific questionnaire (University of California, Los Angeles Prostate Cancer Symptom Index) to determine quality of life outcomes. The catheter was removed on postoperative day 3 or 4 in 263 patients (72%). The reasons for leaving the catheter indwelling were significant leak on cystogram or excessive suprapubic drainage (21%), extensive bladder neck reconstruction (1%) and prolonged hospitalization because of an ileus or other complicating factor (6%). Thirteen patients (3.6%) were either unable to void after catheter removal or presented with retention (not associated with hematuria or clots) after hospital discharge, requiring reinsertion of the Foley catheter. A total of 41 patients (11%) had either an early or late complication (excluding incontinence). There were 3 complications (0.8%) that were considered major because they were potentially life threatening or required a return to the operating room. A pelvic abscess developed in 2 patients and a lymphocele in 1, which required percutaneous drainage. After at least 6 months (mean 20.9 months) 140 patients (89.2%) and 14 (8.9%) reported excellent and good continence, respectively. The patient questionnaire demonstrated bother scores to be minimal to no bother for 95% to 98% of patients at 6 and 12 months. This study confirms that it is safe to remove catheters in most patients 3 to 4 days after prostatectomy if a cystogram demonstrates no extravasation. Complication rates and continence rates with this approach

Pre-surgery Disability Compensation Predicts Long-Term Disability among Workers with Carpal Tunnel Syndrome

PubMed Central

Spector, June T.; Turner, Judith A.; Fulton-Kehoe, Deborah; Franklin, Gary

2012-01-01

Background We sought to identify early risk factors for work disability compensation prior to and after carpal tunnel syndrome (CTS) surgery, and to determine whether pre-surgery disability compensation is associated with long-term disability. Methods Washington State workers’ compensation administrative data and data from interviews with workers 18 days (median) after submitting new workers’ compensation claims for CTS were examined. Baseline risk factors for pre-surgery disability compensation and for long-term disability (≥365 days of work disability compensation prior to two years after claim filing) were evaluated for workers who underwent CTS surgery and had at least one day of disability compensation (N=670). Results After adjustment for baseline long-term disability risk factors, workers with pre-surgery disability compensation had over five times the odds of long-term disability. Baseline factors in multiple domains, including job, psychosocial, clinical, and worker pain and function, were associated with both pre-surgery disability compensation and long-term disability. Conclusions Risk factors for work disability prior to and after CTS surgery are similar, and early work disability is a risk factor for long-term CTS-related disability. An integrated approach to CTS-related disability prevention could include identifying and addressing combined risk factors soon after claim filing, more efficient use of conservative treatments and appropriate work modifications to minimize early work loss, and, when indicated, timely surgical intervention. PMID:22392804

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.

Long-Term Outcomes of Single-Port Laparoscopic Placement of Peritoneal Dialysis Catheter.

PubMed

Pan, Alan; Poi, Mun J; Matos, Jesus; Jiang, Jenny S; Kfoury, Elias; Echeverria, Angela; Bechara, Carlos F; Lin, Peter H

2016-07-01

Laparoscopic insertion of peritoneal dialysis (PD) catheter has become a preferred method compared to the traditional open technique for PD catheter insertion. We retrospectively report the outcome of 1-port laparoscopic placement PD catheters in our institution. A total of 263 patients with end-stage renal disease who underwent single-trocar laparoscopic PD catheter insertion during a recent 6-year period were reviewed. Laparoscopic technique involves introducing a PD catheter over a stiff guidewire into the abdominal cavity through a 10-mm laparoscopic port. Pertinent clinical variables, procedural complications, and follow-up outcome were analyzed. There were 182 men and 81 women. The mean age was 56 years. Technical success was 95.8%. Catheter occlusion was the most common early complications (<6 months) that occurred in 4 (1.5%) patients. Late complications (> 6 months) including catheter occlusion, cuff extrusion, catheter leakage, catheter migration, infection, and hernia occurred in 5 patients (1.9%), 2 patients (0.8%), 3 patients (1.1%), 3 patients (1.1%), 6 patients (2.3%), and 4 patients (1.5), respectively. Mean follow-up time was 39 ± 18 months. Catheter survival rate at 1, 2, 3, 4, and 5 years was 96%, 94%, 90%, 85%, and 82%, respectively. Laparoscopic PD catheter implantation via a single-trocar utilizing a stiff guidewire technique is feasible and safe. This method can result in low complication and high catheter survival rate. © The Author(s) 2016.

Identification of Targets for Prevention of Peritoneal Catheter Tunnel and Exit-Site Infections in Low Incidence Settings.

PubMed

Santos, Clara; Pérez-Fontán, Miguel; Rodríguez-Carmona, Ana; Calvo-Rodríguez, María; López-Muñiz, Andrés; López-Calviño, Beatriz; García-Falcón, Teresa

2016-01-01

♦ Peritoneal catheter tunnel and exit-site infection (TESI) complicates the clinical course of peritoneal dialysis (PD) patients. Adherence to recommendations for catheter insertion, exit-site care, and management of Staphylococcus aureus (SAu) carriage reduces, but does not abrogate the risk of these infections. ♦ To reappraise the risk profile for TESI in an experienced center with a long-term focus on management of SAu carriage and a low incidence of these infections. ♦ Following a retrospective, observational design, we investigated 665 patients incident on PD. The main study variable was survival to the first episode of TESI. We considered selected demographic, clinical, and technical variables, applying multivariate strategies of analysis. ♦ The overall incidence of TESI was 1 episode/68.5 patient-months. Staphylococcus aureus carriage disclosed at inception of PD (but not if observed sporadically during follow-up) (hazard ratio [HR] 1.53, p = 0.009), PD started shortly after catheter insertion (HR 0.98 per day, p = 0.011), PD after kidney transplant failure (HR 2.18, p = 0.017), lower hemoglobin levels (HR 0.88 per g/dL, p = 0.013) and fast peritoneal transport rates (HR 2.92, p = 0.03) portended an increased risk of TESI. Delaying PD ≥ 30 days after catheter insertion markedly improved the probability of TESI. Carriage of methicillin-resistant SAu since the start of PD was associated with a high incidence of TESI by these bacteria. On the contrary, resistance to mupirocin did not predict such a risk, probably due to the use of an alternative regime in affected patients. ♦ Adherence to current recommendations results in a low incidence of TESI in PD patients. Interventions on specific risk subsets have a potential to bring incidence close to negligible levels. Despite systematic screening and management, SAu carriage is still a predictor of TESI. Antibiotic susceptibility patterns may help to refine stratification of the risk of TESI by these

REcanalisation and Balloon-Oriented Puncture for Re-Insertion of Dialysis Catheter in Nonpatent Central Veins (REBORN)

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

Too, Chow Wei, E-mail: toochowwei@gmail.com; Sayani, Raza; Lim, Elvin Yuan Ting

PurposeTo describe a technique involving REcanalisation and Balloon-Oriented puncture for Re-insertion of dialysis catheter in Nonpatent central veins (REBORN) and to report long-term results.Materials and MethodsThis is a retrospective study of ten subjects in whom dialysis catheters were inserted using the REBORN technique from March 2012 to October 2014 and followed up till April 2016. Data on the duration of catheter usage, complications and reasons for removal were obtained. Seven patients had partially occluded lower internal jugular veins (IJV) recanalised in an antegrade fashion via a more cranial puncture. The balloon was then inflated at usual puncture site with anmore » 18G needle. The collapsed balloon was cannulated with a guide wire, and both balloon and guide wire were advanced together into the superior vena cava. This was followed by tunnelled catheter placement using standard techniques. Two patients had catheters placed in the subclavian vein using a similar antegrade technique, and one patient had catheter placed via the left IJV following retrograde recanalisation from a right femoral puncture.ResultsMean duration of catheter use was 278 days (range 32–503). Three catheters were removed due to matured arteriovenous accesses. Four patients had successful catheter change over the same subcutaneous track due to catheter malfunction. One catheter was removed after 7 months because of sepsis. No complications were reported.ConclusionThe REBORN technique allows for the preservation of central veins for future haemodialysis access, which can be challenging in patients requiring long-term dialysis.« less

Home-based drainage of refractory ascites by a permanent-tunneled peritoneal catheter can safely replace large-volume paracentesis.

PubMed

Solbach, Philipp; Höner Zu Siederdissen, Christoph; Taubert, Richard; Ziegert, Szilvia; Port, Kerstin; Schneider, Andrea; Hueper, Katja; Manns, Michael P; Wedemeyer, Heiner; Jaeckel, Elmar

2017-05-01

Refractory ascites has a poor prognosis. Recurrent large-volume paracentesis is the current standard of care; however, it results in circulatory dysfunction and renal dysfunction, and hospitalization is commonly required. Transjugular intrahepatic portosystemic shunt placement is not an option in a substantial number of patients because of contraindications. The placement of a tunneled peritoneal drainage catheter has been shown to be effective in patients with malignant ascites. However, data in patients with nonmalignant refractory ascites are rare. We followed 24 consecutive patients in whom tunneled peritoneal drainage catheters were placed in the Endoscopy Unit at Hannover Medical School between June 2013 and December 2014. Catheters were placed in 24 patients with refractory ascites in end-stage liver disease and with a contraindication to transjugular intrahepatic portosystemic shunt placement. Placement was technically successful in all patients. The dosage of diuretics could be reduced significantly. The number of paracentesis decreased from 2.2±1 to 0 per week, although the volume of daily ascites removal remained stable (2 l). Despite frequent drainage of ascites, kidney function, serum sodium, and serum albumin remained stable. Seven adverse events occurred in six (25%) patients. Five patients listed for liver transplantation underwent successful transplantation without a negative impact. The tunneled peritoneal drainage catheter placement is a viable and effective treatment alternative in patients with refractory ascites because of end-stage liver disease, reducing diuretic intake and the need for paracentesis. The procedure avoids hyponatremia, worsening kidney function, and albumin infusions without an increased risk of spontaneous bacterial peritonitis.

A pilot study to assess adductor canal catheter tip migration in a cadaver model.

PubMed

Leng, Jody C; Harrison, T Kyle; Miller, Brett; Howard, Steven K; Conroy, Myles; Udani, Ankeet; Shum, Cynthia; Mariano, Edward R

2015-04-01

An adductor canal catheter may facilitate early ambulation after total knee arthroplasty, but there is concern over preoperative placement since intraoperative migration of catheters may occur from surgical manipulation and result in ineffective analgesia. We hypothesized that catheter type and subcutaneous tunneling may influence tip migration for preoperatively inserted adductor canal catheters. In a male unembalmed human cadaver, 20 catheter insertion trials were divided randomly into one of four groups: flexible epidural catheter either tunneled or not tunneled; or rigid stimulating catheter either tunneled or not tunneled. Intraoperative patient manipulation was simulated by five range-of-motion exercises of the knee. Distance and length measurements were performed by a blinded regional anesthesiologist. Changes in catheter tip to nerve distance (p = 0.225) and length of catheter within the adductor canal (p = 0.467) were not different between the four groups. Two of five non-tunneled stimulating catheters (40 %) were dislodged compared to 0/5 in all other groups (p = 0.187). A cadaver model may be useful for assessing migration of regional anesthesia catheters; catheter type and subcutaneous tunneling may not affect migration of adductor canal catheters based on this preliminary study. However, future studies involving a larger sample size, actual patients, and other catheter types are warranted.

Short-term infection in cuffed versus noncuffed small bore central catheters: a randomized trial.

PubMed

Trerotola, Scott O; Patel, Aalpen A; Shlansky-Goldberg, Richard D; Solomon, Jeffrey A; Mondschein, Jeffrey I; Stavropoulos, S William; Soulen, Michael C; Itkin, Maxim; Chittams, Jesse

2010-02-01

To determine if a polyester cuff offered benefit in jugular small-bore central catheters (SBCCs). Eighty-four patients were randomly assigned to receive a 5-F single- or 6-F dual-lumen SBCC with (n = 42) or without (n = 42) a polyester cuff. Follow-up was performed at 2 weeks, 1 month, and 3 months or at catheter removal, whichever came first. At scheduled follow-up, catheter function, patient satisfaction, and infection were determined. At catheter removal, tip culture was performed to determine colonization and jugular vein patency was determined with ultrasonography (US). The overall infection rate was 0.4 per 1,000 catheter days. There was one clinical infection (noncuffed catheter). Colonization occurred in two noncuffed catheters and one cuffed catheter. There was one catheter dislodgment in the noncuffed group and none in the cuffed group. Cuffed catheters were no more difficult to insert but took slightly longer to remove (6 minutes +/- 4.7 vs 5 minutes +/- 3, P = .39) and often required local anesthesia for removal, whereas noncuffed catheters did not (41% vs 0%, P = .001). Partial (two cuffed, 0 noncuffed) or complete (two cuffed, one noncuffed) jugular thrombosis was seen on five of 58 completion US studies (8.6%). A polyester cuff on a SBCC confers no significant benefit in short-term colonization rates. Infection in SBCCs is uncommon. Despite their small diameters, SBCCs can result in jugular thrombosis, an important consideration in any patient requiring long-term venous access. Copyright (c) 2010 SIR. Published by Elsevier Inc. All rights reserved.

Serratia marcescens bacteraemia outbreak in haemodialysis patients with tunnelled catheters due to colonisation of antiseptic solution. Experience at 4 hospitals.

PubMed

Merino, José L; Bouarich, Hanane; Pita, Mª José; Martínez, Patricia; Bueno, Blanca; Caldés, Silvia; Corchete, Elena; Jaldo, Mª Teresa; Espejo, Beatriz; Paraíso, Vicente

The application of antiseptic solution for handling tunnelled catheters is recommended in patients undergoing haemodialysis. These routine antiseptic procedures in handling catheters are crucial to avoid complications. We report an outbreak of Serratia marcescens (S. marcescens) bacteraemia in numerous haemodialysis units of the Community of Madrid. The first cases of bacteraemia due to S. marcescens were isolated in December 2014. The Preventive Medicine Services were informed of the detection of an atypical pathogen in several patients, suspecting a probable nosocomial outbreak. Information from 4 centres with similar S. marcescens bacteraemia was analysed. Twenty-one cases of bacteraemia related to S. marcescens were identified. The mean age of affected patients was 72±10 years. The mean time on haemodialysis of affected patients was 33±13 months (range: 3-83 months), the median time of tunnelled catheter was 22±13 months. In 11 cases the clinical picture was similar, with hypotension and general malaise during the haemodialysis session. Fever was present in a further 7 cases. In 3 cases the presentation was asymptomatic and was detected by blood cultures. All patients had tunnelled catheters (12 patients with catheter in the right jugular vein, 5 in the left jugular, 2 in the right femoral artery and 2 in the left subclavian artery). Gentamicin intravenous doses (1mg/kg) with catheter lock solution with ciprofloxacin post-dialysis were administered for 3 weeks in 6 patients. In 12 patients the treatment was ceftazidime (2g IV) plus catheter lock solution with the same antibiotic, for 2 weeks. Four patients received oral ciprofloxacin for 2 weeks, in one case together with IV vancomycin. The patients were asymptomatic and without new episodes 48hours after the treatment. No major complications were observed. The teams informed the health authorities of the situation, which then reported the presence of batches of antiseptic (chlorhexidine 0.05 and 2

A simple method for long-term biliary access in large animals.

PubMed

Andrews, J C; Knutsen, C; Smith, P; Prieskorn, D; Crudip, J; Klevering, J; Ensminger, W D

1988-07-01

A simple method to obtain long-term access to the biliary tree in dogs and pigs is presented. In ten dogs and four pigs, a cholecystectomy was performed, the cystic duct isolated, and a catheter inserted into the cut end of the cystic duct. The catheter was connected to a subcutaneous infusion port, producing a closed, internal system to allow long-term access. The catheter placement was successful in three of the pigs and all of the dogs. Thirty-five cholangiograms were obtained in the 13 subjects by accessing the port with a 20 gauge Huber needle and injecting small amounts (4-10 mL) of contrast under fluoroscopic control. Cholangiograms were obtained up to four months after catheter placement without evidence for catheter failure or surgically induced changes in the biliary tree. This model provides a simple, reliable means to obtain serial cholangiograms in a research setting.

Executive summary: Diagnosis and Treatment of Catheter-Related Bloodstream Infection: Clinical Guidelines of the Spanish Society of Clinical Microbiology and Infectious Diseases (SEIMC) and the Spanish Society of Intensive Care Medicine and Coronary Units (SEMICYUC).

PubMed

Chaves, Fernando; Garnacho-Montero, José; Del Pozo, José Luis; Bouza, Emilio; Capdevila, José Antonio; de Cueto, Marina; Domínguez, M Ángeles; Esteban, Jaime; Fernández-Hidalgo, Nuria; Fernández Sampedro, Marta; Fortún, Jesús; Guembe, María; Lorente, Leonardo; Paño, Jose Ramón; Ramírez, Paula; Salavert, Miguel; Sánchez, Miguel; Vallés, Jordi

2018-02-01

Catheter-related bloodstream infections (CRBSI) constitute an important cause of hospital-acquired infection associated with morbidity, mortality, and cost. The aim of these guidelines is to provide updated recommendations for the diagnosis and management of CRBSI in adults. Prevention of CRBSI is excluded. Experts in the field were designated by the two participating Societies (Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica and the Sociedad Española de Medicina Intensiva, Crítica y Unidades Coronarias). Short-term peripheral venous catheters, non-tunneled and long-term central venous catheters, tunneled catheters and hemodialysis catheters are covered by these guidelines. The panel identified 39 key topics that were formulated in accordance with the PICO format. The strength of the recommendations and quality of the evidence were graded in accordance with ESCMID guidelines. Recommendations are made for the diagnosis of CRBSI with and without catheter removal and of tunnel infection. The document establishes the clinical situations in which a conservative diagnosis of CRBSI (diagnosis without catheter removal) is feasible. Recommendations are also made regarding empirical therapy, pathogen-specific treatment (coagulase-negative staphylococci, Sthaphylococcus aureus, Enterococcus spp, Gram-negative bacilli, and Candida spp), antibiotic lock therapy, diagnosis and management of suppurative thrombophlebitis and local complications. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Long-term symptomatic, functional, and work outcomes of carpal tunnel syndrome among construction workers.

PubMed

Evanoff, Bradley; Gardner, Bethany T; Strickland, Jaime R; Buckner-Petty, Skye; Franzblau, Alfred; Dale, Ann Marie

2016-05-01

The long-term outcomes of carpal tunnel syndrome (CTS) including symptoms, functional status, work disability, and economic impact are unknown. We conducted a retrospective study of 234 active construction workers with medical claims for CTS and 249 workers without CTS claims; non-cases were matched on age, trade, and insurance eligibility. We conducted telephone interviews with cases and non-cases and collected administrative data on work hours. Compared to non-cases, CTS cases were more likely to report recurrent hand symptoms, decreased work productivity/quality, decreased performance of physical work demands, and greater functional limitations. Surgical cases showed larger improvements on multiple outcomes than non-surgical cases. Minimal differences in paid work hours were seen between cases and non-cases in the years preceding and following CTS claims. Persistent symptoms and functional impairments were present several years after CTS diagnosis. Long-term functional limitations shown by this and other studies indicate the need for improved prevention and treatment. © 2016 Wiley Periodicals, Inc.

Immersion-scanning-tunneling-microscope for long-term variable-temperature experiments at liquid-solid interfaces

NASA Astrophysics Data System (ADS)

Ochs, Oliver; Heckl, Wolfgang M.; Lackinger, Markus

2018-05-01

Fundamental insights into the kinetics and thermodynamics of supramolecular self-assembly on surfaces are uniquely gained by variable-temperature high-resolution Scanning-Tunneling-Microscopy (STM). Conventionally, these experiments are performed with standard ambient microscopes extended with heatable sample stages for local heating. However, unavoidable solvent evaporation sets a technical limit on the duration of these experiments, hence prohibiting long-term experiments. These, however, would be highly desirable to provide enough time for temperature stabilization and settling of drift but also to study processes with inherently slow kinetics. To overcome this dilemma, we propose a STM that can operate fully immersed in solution. The instrument is mounted onto the lid of a hermetically sealed heatable container that is filled with the respective solution. By closing the container, both the sample and microscope are immersed in solution. Thereby solvent evaporation is eliminated and an environment for long-term experiments with utmost stable and controllable temperatures between room-temperature and 100 °C is provided. Important experimental requirements for the immersion-STM and resulting design criteria are discussed, the strategy for protection against corrosive media is described, the temperature stability and drift behavior are thoroughly characterized, and first long-term high resolution experiments at liquid-solid interfaces are presented.

Radiologically Guided Placement of Mushroom-retained Gastrostomy Catheters: Long-term Outcomes of Use in 300 Patients at a Single Center.

PubMed

Ahmed, Osman; Jilani, Danial; Sheth, Sujay; Giger, Maryellen; Funaki, Brian

2015-08-01

To assess long-term outcomes including risk of complications and nutritional benefits of mushroom-retained (pull-type) gastrostomy catheters placed in patients by interventional radiologists. All patients who received pull-type gastrostomy tubes between 2010 and 2013 were retrospectively reviewed, including 142 men (average weight, 169.6 lb [76.32 kg]; mean age, 65.2 years; range, 22-92 years) and 158 women (average weight, 150.4 lb [67.68 kg]; mean age, 65.2 years; range, 18-98 years). Indications for placement were cerebrovascular accident (n = 80), failure to thrive (n = 71), other central nervous system disorder (n = 51), head and neck cancer (n = 47), and other malignancy (n = 51). Complications were recorded per Society of Interventional Radiology practice guidelines. Patient weight was documented at specific follow-up intervals. Statistical analysis was performed by using the Student t test and one-way analysis of variance for the effects of sex and indication for placement, respectively, on average weight change. The technical success rate was 98.4% (300 of 305 patients). Major and minor complications occurred at a rate of 3.7% (n = 11) and 13% (n = 39), respectively. Follow-up weight during the early (≤45 days), intermediate (≤180 days), and long-term (>180 days) periods was available for 71% (n = 214), 36% (n = 108), and 15% (n = 44) of the 300 patients, respectively. Weight gain occurred in 77% (160 of 214), 60% (65 of 108), and 73% (32 of 44) of the patients, respectively. Patients who gained weight gained 6.7, 10.6, and 16.3 lb (3.02, 4.77, and 7.34 kg) during each follow-up period, respectively. Average weight gain at follow-up in all patients was 4.2, 0.6, and 5.4 lb (1.89, 0.27, and 2.43 kg), respectively. No significant differences in average weight change were seen among groups when they were classified according to sex or indication for placement. Placement of mushroom-retained gastrostomy catheters is a viable long-term treatment option for

[Urinary catheter biofilm infections].

PubMed

Holá, V; Růzicka, F

2008-04-01

Urinary tract infections, most of which are biofilm infections in catheterized patients, account for more than 40% of hospital infections. Bacterial colonization of the urinary tract and catheters causes not only infection but also other complications such as catheter blockage by bacterial encrustation, urolithiasis and pyelonephritis. About 50% of long-term catheterized patients face urinary flow obstruction due to catheter encrustation, but no measure is currently available to prevent it. Encrustation has been known either to result from metabolic dysfunction or to be of microbial origin, with urease positive bacterial species implicated most often. Infectious calculi account for about 15-20% of all cases of urolithiasis and are often associated with biofilm colonization of a long-term indwelling urinary catheter or urethral stent. The use of closed catheter systems is helpful in reducing such problems; nevertheless, such a system only delays the inevitable, with infections emerging a little later. Various coatings intended to prevent the bacterial adhesion to the surface of catheters and implants and thus also the emergence of biofilm infections, unfortunately, do not inhibit the microbial adhesion completely and permanently and the only reliable method for biofilm eradication remains the removal of the foreign body from the patient.

[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

Tunneled catheters with taurolidine-citrate-heparin lock solution significantly improve the inflammatory profile of hemodialysis patients.

PubMed

Fontseré, Néstor; Cardozo, Celia; Donate, Javier; Soriano, Alex; Muros, Mercedes; Pons, Mercedes; Mensa, Josep; Campistol, Josep M; Navarro-González, Juan F; Maduell, Francisco

2014-07-01

Mortality and morbidity are significantly higher among patients with dialysis catheters, which has been associated with chronic activation of the immune system. We hypothesized that bacteria colonizing the catheter lumen trigger an inflammatory response. We aimed to evaluate the inflammatory profile of hemodialysis patients before and after locking catheters with an antimicrobial lock solution. High-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), IL-10, and tumor necrosis factor alpha (TNF-α) were measured in serum, and levels of mRNA gene expression of IL-6, IL-10, and TNF-α were analyzed in peripheral blood mononuclear cells (PBMC). Samples were obtained at baseline and again after 3 months' use of taurolidine-citrate-heparin lock solution (TCHLS) in 31 hemodialysis patients. The rate of catheter-related bloodstream infections (CRBSI) was 1.08 per 1,000 catheter-days in the heparin period and 0.04 in the TCHLS period (P = 0.023). Compared with the baseline data, serum levels of hs-CRP and IL-6 showed median percent reductions of 18.1% and 25.2%, respectively (P < 0.01), without significant changes in TNF-α or IL-10 levels. Regarding cytokine gene expression in PBMC, the median mRNA expression levels of TNF-α and IL-6 decreased by 20% (P < 0.05) and 19.7% (P = 0.01), respectively, without changes in IL-10 expression levels. The use of TCHLS to maintain the catheter lumen sterility significantly reduces the incidence of CRBSI and improves the inflammatory profile in hemodialysis patients with tunneled catheters. Further studies are needed to evaluate the potential beneficial effects on clinical outcomes. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Tunneled Catheters with Taurolidine-Citrate-Heparin Lock Solution Significantly Improve the Inflammatory Profile of Hemodialysis Patients

PubMed Central

Cardozo, Celia; Donate, Javier; Soriano, Alex; Muros, Mercedes; Pons, Mercedes; Mensa, Josep; Campistol, Josep M.; Navarro-González, Juan F.; Maduell, Francisco

2014-01-01

Mortality and morbidity are significantly higher among patients with dialysis catheters, which has been associated with chronic activation of the immune system. We hypothesized that bacteria colonizing the catheter lumen trigger an inflammatory response. We aimed to evaluate the inflammatory profile of hemodialysis patients before and after locking catheters with an antimicrobial lock solution. High-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), IL-10, and tumor necrosis factor alpha (TNF-α) were measured in serum, and levels of mRNA gene expression of IL-6, IL-10, and TNF-α were analyzed in peripheral blood mononuclear cells (PBMC). Samples were obtained at baseline and again after 3 months' use of taurolidine-citrate-heparin lock solution (TCHLS) in 31 hemodialysis patients. The rate of catheter-related bloodstream infections (CRBSI) was 1.08 per 1,000 catheter-days in the heparin period and 0.04 in the TCHLS period (P = 0.023). Compared with the baseline data, serum levels of hs-CRP and IL-6 showed median percent reductions of 18.1% and 25.2%, respectively (P < 0.01), without significant changes in TNF-α or IL-10 levels. Regarding cytokine gene expression in PBMC, the median mRNA expression levels of TNF-α and IL-6 decreased by 20% (P < 0.05) and 19.7% (P = 0.01), respectively, without changes in IL-10 expression levels. The use of TCHLS to maintain the catheter lumen sterility significantly reduces the incidence of CRBSI and improves the inflammatory profile in hemodialysis patients with tunneled catheters. Further studies are needed to evaluate the potential beneficial effects on clinical outcomes. PMID:24820084

Long-Term Outcomes of Catheter Ablation of Ventricular Tachycardia in Patients With Cardiac Sarcoidosis.

PubMed

Muser, Daniele; Santangeli, Pasquale; Pathak, Rajeev K; Castro, Simon A; Liang, Jackson J; Magnani, Silvia; Hayashi, Tatsuya; Garcia, Fermin C; Hutchinson, Mathew D; Supple, Gregory E; Frankel, David S; Riley, Michael P; Lin, David; Schaller, Robert D; Desjardins, Benoit; Dixit, Sanjay; Callans, David J; Zado, Erica S; Marchlinski, Francis E

2016-08-01

Catheter ablation (CA) of ventricular tachycardia (VT) in patients with cardiac sarcoidosis can be challenging because of the complex underlying substrate. We sought to determine the long-term outcome of CA of VT in patients with cardiac sarcoidosis. We enrolled 31 patients (age, 55±10 years) with diagnosis of cardiac sarcoidosis based on Heart Rhythm Society criteria and VT who underwent CA. In 23 (74%) patients, preprocedure cardiac magnetic resonance imaging and positron emission tomographic (PET) evaluation were performed. Preprocedure magnetic resonance imaging was positive for late gadolinium enhancement in 21 of 23 (91%) patients, whereas abnormal 18-fluorodeoxyglucose uptake was found in 15 of 23 (65%) cases. In 14 of 15 patients with positive PET at baseline, PET was repeated after 6.1±3.7-month follow-up. After a median follow-up of 2.5 (range, 0-10.5) years, 1 (3%) patient died and 4 (13%) underwent heart transplant. Overall VT-free survival was 55% at 2-year follow-up. Among the 16 (52%) patients with VT recurrences, CA resulted in a significant reduction of VT burden, with 8 (50%) having only isolated (1-3) VT episodes and only 1 patient with recurrent VT storm. The presence of late gadolinium enhancement at magnetic resonance imaging, a positive PET at baseline, and lack of PET improvement over follow-up were associated with increased risk of recurrent VT. In patients with cardiac sarcoidosis and VT, CA is effective in achieving long-term freedom from VT or improvement in VT burden in the majority of patients. The presence of late gadolinium enhancement at magnetic resonance imaging, a positive PET scan at baseline, or lack of improvement at repeat PET over follow-up predict worse arrhythmia-free survival. © 2016 American Heart Association, Inc.

Long-term efficacy of single procedure remote magnetic catheter navigation for ablation of ischemic ventricular tachycardia: a retrospective study.

PubMed

Dinov, Borislav; Schönbauer, Robert; Wojdyla-Hordynska, Agnieska; Braunschweig, Frieder; Richter, Sergio; Altmann, David; Sommer, Philipp; Gaspar, Thomas; Bollmann, Andreas; Wetzel, Ulrike; Rolf, Sascha; Piorkowski, Christopher; Hindricks, Gerhard; Arya, Arash

2012-05-01

Remote magnetic navigation (RMN) aims to reduce some inherent limitations of manual radiofrequency (RF) ablation. However, data comparing the effectiveness of both methods are scarce. This study evaluated the acute and long-term success of RMN guided versus manual RF ablation in patients with ischemic sustained ventricular tachycardia (sVT). One hundred two consecutive patients (age 68 ± 10 years, LVEF 32 ± 12%, 88 men) with ischemic sVT were ablated with RMN (Stereotaxis; 49%) or manually (51%) using substrate and/or activation mapping (Carto) and open-irrigated-tip catheters. All received implantable defibrillators or loop recorders. Acute success was defined as noninducibility of any sVT at the end of the ablation procedure and long-term success as freedom from VT upon follow-up. There was no difference in the baseline characteristics between the groups. Three patients died in hospital. Acute success rate was similar for RMN and manual ablation (82% vs 71%, P = 0.246). RMN was associated with significantly shorter fluoroscopy time (13 ± 12 minutes vs 32 ± 17 minutes, P = 0.0001) and RF time (2337.59 ± 1248.22 seconds vs 1589.95 ± 1047.42 seconds, P = 0.049), although total procedure time was similar (157 ± 40 minutes vs 148 ± 50 minutes, P = 0.42). There was a nonsignificant trend toward better long-term success in RMN group: after a median of 13 (range 1-34) months, 63% in the RMN and 53% in the manual ablation group were free from VT recurrence (P = 0.206). RMN guided RF ablation of ischemic sustained VT is equally efficient compared with manual ablation in terms of acute and long-term success rate. These results are achieved with a significantly reduced fluoroscopy time and shorter RF time. © 2012 Wiley Periodicals, Inc.

Retained embolized fragment of totally implantable central venous catheter in right ventricle: it is really necessary to remove?

PubMed

Tazzioli, Giovanni; Gargaglia, Eleonora; Vecchioni, Ilaria; Papi, Simona; Di Blasio, Petronilla; Rossi, Rosario

2015-01-01

Central venous catheters are often required in oncologic patients for long-term safe administration of chemotherapeutic agents, antibiotics, and parenteral nutrition. Rupture of these devices and intracardiac migration is a rare complication. We report one spontaneous rupture and embolization of a totally implantable vascular access device (TIVAD) in an asymptomatic patient. A 50-year-old woman received a TIVAD silicone catheter 8 FR for adjuvant chemotherapy. After 3 years of port time in situ, during a follow-up control, a catheter malfunction was found and radiologic investigations showed a rupture and migration of the catheter to the right ventricle. The attempt to remove the fragment under fluoroscopic control using the femoral route was unsuccessful. We did not try a surgical approach because of the complete absence of symptomatology and hemodynamic impairment. The catheter rupture and intracardiac embolization is a rare complication associated with totally implantable or tunneled central venous catheters. When such an event happens, the patient should be managed by expert hemodynamists or interventional radiologists making an effort to remove the fragment without surgical measures. When the intravascular percutaneous route fails, the possibility to leave the fragmented catheter in heart chambers should be evaluated, being surgery questionable in asymptomatic patients.

Catheter-related bloodstream infection with removal of catheter in pediatric oncology patients: a 10-year experience in Taiwan.

PubMed

Chen, Shih-Hsiang; Yang, Chao-Ping; Jaing, Tang-Her; Lai, Jin-Yao; Hung, Iou-Jih

2012-04-01

Long-term central venous catheter (CVC) implantation has become more affordable in Taiwan since 1995. Surgical removal of the catheter may be the essential treatment for catheter-related bloodstream infections (CRBSI). The aim of this study was to evaluate the clinical features and microbial isolates in pediatric cancer patients with removal of CVC for CRBSI. The records of positive blood culture from hospitalized pediatric oncology patients between 1995 and 2004 were reviewed. One hundred and forty-three patients implanted with a long-term CVC were further identified. Seventeen catheters in 16 patients developed catheter-related bacteremia that needed catheter removal. The rate of catheter removal was 11.9%. The median device life was 7.7 months. Six catheters were removed within 3 months of insertion. Nine of the 17 catheters were removed from patient younger than 2 years. Eight infections occurred during severe neutropenia, and 6 patients had refractory or relapsed underlying disease. The cultural isolates were Gram-negative bacilli in 7, Gram-positive in 5, fungi in 5, and atypical mycobacterium in 1. The frequency of catheter removal for infection control was significantly higher in the first 5 years (1994-1999) compared to the last 5 years (2000-2004) (30.9 vs. 4.0%, p = 2.3 × 10(-4)). Factors such as microbiological isolates, age of infection, the status of malignancy, and neutropenia are related to catheter outcome. The reduction in patients with positive cultures needing removal of the catheters can be related to improved nursing care and more aggressive antibiotic therapy.

Peritoneal Dialysis Catheter Insertion.

PubMed

Crabtree, John H; Chow, Kai-Ming

2017-01-01

The success of peritoneal dialysis as renal-replacement therapy depends on a well-functioning peritoneal catheter. Knowledge of best practices in catheter insertion can minimize the risk of catheter complications that lead to peritoneal dialysis failure. The catheter placement procedure begins with preoperative assessment of the patient to determine the most appropriate catheter type, insertion site, and exit site location. Preoperative preparation of the patient is an instrumental step in facilitating the performance of the procedure, avoiding untoward events, and promoting the desired outcome. Catheter insertion methods include percutaneous needle-guidewire with or without image guidance, open surgical dissection, peritoneoscopic procedure, and surgical laparoscopy. The insertion technique used often depends on the geographic availability of material resources and local provider expertise in placing catheters. Independent of the catheter implantation approach, adherence to a number of universal details is required to ensure the best opportunity for creating a successful long-term peritoneal access. Finally, appropriate postoperative care and catheter break-in enables a smooth transition to dialysis therapy. Copyright © 2017 Elsevier Inc. All rights reserved.

Tunnelled haemodialysis catheter and haemodialysis outcomes: a retrospective cohort study in Zagreb, Croatia.

PubMed

Pašara, Vedran; Maksimović, Bojana; Gunjača, Mihaela; Mihovilović, Karlo; Lončar, Andrea; Kudumija, Boris; Žabić, Igor; Knotek, Mladen

2016-05-17

Studies have reported that the tunnelled dialysis catheter (TDC) is associated with inferior haemodialysis (HD) patient survival, in comparison with arteriovenous fistula (AVF). Since many cofactors may also affect survival of HD patients, it is unclear whether the greater risk for survival arises from TDC per se, or from associated conditions. Therefore, the aim of this study was to determine, in a multivariate analysis, the long-term outcome of HD patients, with respect to vascular access (VA). Retrospective cohort study. This retrospective cohort study included all 156 patients with a TDC admitted at University Hospital Merkur, from 2010 to 2012. The control group consisted of 97 patients dialysed via AVF. The groups were matched according to dialysis unit and time of VA placement. The site of choice for the placement of the TDC was the right jugular vein. Kaplan-Meier analysis with log-rank test was used to assess patient survival. Multivariate Cox regression analysis was used to determine independent variables associated with patient survival. Patient survival with respect to VA. The cumulative 1-year survival of patients who were dialysed exclusively via TDC was 86.4% and of those who were dialysed exclusively via AVF, survival was 97.1% (p=0.002). In multivariate Cox regression analysis, male sex and older age were independently negatively associated with the survival of HD patients, while shorter HD vintage before the creation of the observed VA, hypertensive renal disease and glomerulonephritis were positively associated with survival. TDC was an independent risk factor for survival of HD patients (HR 23.0, 95% CI 6.2 to 85.3). TDC may be an independent negative risk factor for HD patient survival. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Long-range electron tunneling.

PubMed

Winkler, Jay R; Gray, Harry B

2014-02-26

Electrons have so little mass that in less than a second they can tunnel through potential energy barriers that are several electron-volts high and several nanometers wide. Electron tunneling is a critical functional element in a broad spectrum of applications, ranging from semiconductor diodes to the photosynthetic and respiratory charge transport chains. Prior to the 1970s, chemists generally believed that reactants had to collide in order to effect a transformation. Experimental demonstrations that electrons can transfer between reactants separated by several nanometers led to a revision of the chemical reaction paradigm. Experimental investigations of electron exchange between redox partners separated by molecular bridges have elucidated many fundamental properties of these reactions, particularly the variation of rate constants with distance. Theoretical work has provided critical insights into the superexchange mechanism of electronic coupling between distant redox centers. Kinetics measurements have shown that electrons can tunnel about 2.5 nm through proteins on biologically relevant time scales. Longer-distance biological charge flow requires multiple electron tunneling steps through chains of redox cofactors. The range of phenomena that depends on long-range electron tunneling continues to expand, providing new challenges for both theory and experiment.

Quantum gases. Observation of many-body dynamics in long-range tunneling after a quantum quench.

PubMed

Meinert, Florian; Mark, Manfred J; Kirilov, Emil; Lauber, Katharina; Weinmann, Philipp; Gröbner, Michael; Daley, Andrew J; Nägerl, Hanns-Christoph

2014-06-13

Quantum tunneling is at the heart of many low-temperature phenomena. In strongly correlated lattice systems, tunneling is responsible for inducing effective interactions, and long-range tunneling substantially alters many-body properties in and out of equilibrium. We observe resonantly enhanced long-range quantum tunneling in one-dimensional Mott-insulating Hubbard chains that are suddenly quenched into a tilted configuration. Higher-order tunneling processes over up to five lattice sites are observed as resonances in the number of doubly occupied sites when the tilt per site is tuned to integer fractions of the Mott gap. This forms a basis for a controlled study of many-body dynamics driven by higher-order tunneling and demonstrates that when some degrees of freedom are frozen out, phenomena that are driven by small-amplitude tunneling terms can still be observed. Copyright © 2014, American Association for the Advancement of Science.

Long-term outcome of catheter ablation for left posterior fascicular ventricular tachycardia with the development of left posterior fascicular block and characteristics of repeat procedures.

PubMed

Luo, Bin; Zhou, Gongbu; Guo, Xiaogang; Liu, Xu; Yang, Jiandu; Sun, Qi; Ma, Jian; Zhang, Shu

2017-06-01

The present study aimed to retrospectively investigate long-term clinical outcomes of patients undergoing catheter ablation of left posterior fascicular ventricular tachycardia (LPF-VT) with the development of left posterior fascicular block (LPF block) and characteristics of repeat procedures. A total of 195 patients (mean age 29.76±1.03years, 16.4% females) who underwent catheter ablation for LPF-VT were consecutively enrolled. The earliest ventricular potential with a single fused Purkinje potential (PP) during VT and the PP located in the inferior-apical or mid-apical septum during SR were targeted for linear ablation. The endpoint of the procedure was noninducible VT and development of new-onset LPF block. Follow-up with clinic visits or telephonic interviews, electrocardiogram (ECG), or Holter monitoring was performed after the procedure. With a median follow-up of 85 (18,181) months, 20 patients were censored and 152 of 175 (86.86%) patients had long-term freedom from VT after a single procedure. No statistical difference in the outcome of catheter ablation of LPF-VT was found between inducible and non-inducible groups (P=0.89). Twenty-three patients exhibited recurrent LPF-VT. Seven of 23 patients developed new-onset left upper septal ventricular tachycardia that was successfully ablated. All the patients undergoing repeat procedures had freedom from VT. No procedural complications occurred. Ablation of LPF-VT using the development of LPF block as the endpoint is associated with a high procedural success rate. No difference in freedom from LPF-VT was found between inducible and non-inducible patients. New-onset LPF block recovery and non-early PP-QRS interval can be the predictors of LPF-VT repeat procedure. Copyright © 2017 Elsevier B.V. All rights reserved.

Catheter associated urinary tract infections

PubMed Central

2014-01-01

Urinary tract infection attributed to the use of an indwelling urinary catheter is one of the most common infections acquired by patients in health care facilities. As biofilm ultimately develops on all of these devices, the major determinant for development of bacteriuria is duration of catheterization. While the proportion of bacteriuric subjects who develop symptomatic infection is low, the high frequency of use of indwelling urinary catheters means there is a substantial burden attributable to these infections. Catheter-acquired urinary infection is the source for about 20% of episodes of health-care acquired bacteremia in acute care facilities, and over 50% in long term care facilities. The most important interventions to prevent bacteriuria and infection are to limit indwelling catheter use and, when catheter use is necessary, to discontinue the catheter as soon as clinically feasible. Infection control programs in health care facilities must implement and monitor strategies to limit catheter-acquired urinary infection, including surveillance of catheter use, appropriateness of catheter indications, and complications. Ultimately, prevention of these infections will require technical advances in catheter materials which prevent biofilm formation. PMID:25075308

Risk of catheter-associated infection in young hematology/oncology patients receiving long-term peripheral nerve blocks.

PubMed

Anghelescu, Doralina L; Harris, Brittney L; Faughnan, Lane G; Oakes, Linda L; Windsor, Kelley B; Wright, Becky B; McCullers, Jonathan A

2012-11-01

Continuous peripheral nerve blocks (CPNBs) are increasingly used to control postoperative and chronic pain. At our pediatric oncology institution, the duration of CPNBs is often prolonged. The risk of catheter-associated infection with prolonged CPNBs has not been previously investigated. We analyzed the incidence of CPNB-related infection and its relation to catheter duration, catheter site, intensive care stay, and antibiotic coverage. All CPNBs placed at our institution between August 1, 2005 and October 31, 2010 were studied. Primary diagnosis and the site, indication, duration, and infectious adverse effects of CPNBs were obtained from our Pain Service QI database. Patients' age and sex, antibiotic administration, and number of days in intensive care were collected from patients' medical records. The use of 179 catheters in 116 patients was evaluated. Mean age at CPNB placement was 15.1 years (median, 14.7; range, 0.4-26.9). The most frequent indication for CPNB was surgery (89.4%), most commonly orthopedic (78.8%). Mean CPNB duration was 7.2 days (median, 5.0; range, 1-81 days). Two cases (1.12%) of CPNBs developed signs of infection, both associated with femoral catheters. The infections were mild and necessitated catheter removal at days 10 and 13, respectively. Nerve block catheter-associated infections are infrequent at our institution despite prolonged CPNB use. Both patients with infection had femoral catheters and prolonged catheter (≥ 10 days) use. © 2012 Blackwell Publishing Ltd.

[Incidence and risk factors for infections from hemodialysis catheters].

PubMed

Jean, G

2001-01-01

We report here a revue of hemodialysis catheter-related infections data published since 1985. The reported prevalence of bacteremia is 1 to 20% of catheters, and incidence is 0.72 to 9/1000 catheter-days. Local infection is reported in 6 to 63% of catheters and in 1 to 5/1000 catheter-days. Tunneled catheters and implantables chambers reported less infection rate. The most severe complication is endocarditis (4% rate). Death occurs in 8 to 20% of cases. Reported microbial data show that Staphylococcus aureus (SA) is responsible for most infections ahead of non-aureus Staphylococcus. SA skin colonisation is a risk factor for catheter colonisation and the first step of infection. On the other hand, the host immunity impairment in hemodialysis patients seems a significant risk factor. Iron overload, specially after blood transfusions, older age, diabetes mellitus, low serum albumin level, previous history of bacteremia and immunosuppressive treatment have been frequently involved. Other catheter-related factors are time of use, absence of tunnel and use for parenteral nutrition. Nurses plans, dressing type and frequency, nurses work experience are also important. In spite of recent progress in risk factor understanding, hemodialysis-related infection remains frequent. Multicentre studies are necessary to better evaluated care protocols and new catheter material.

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.

Correlation Between Glycemic Control and the Incidence of Peritoneal and Catheter Tunnel and Exit-Site Infections in Diabetic Patients Undergoing Peritoneal Dialysis

PubMed Central

Rodríguez-Carmona, Ana; Pérez-Fontán, Miguel; López-Muñiz, Andrés; Ferreiro-Hermida, Tamara; García-Falcón, Teresa

2014-01-01

♦ Background: Diabetes mellitus, especially if complicated by poor glycemic control, portends an increased risk of infection. The significance of this association in the case of diabetic patients undergoing peritoneal dialysis (PD) has not been assessed. ♦ Methods: Using a retrospective observational design, we analyzed the association between glycemic control at the start of PD (estimated from glycosylated hemoglobin levels) and the risk of peritoneal and catheter tunnel and exit-site infections during follow-up in 183 incident patients on PD. We used the median value of glycosylated hemoglobin to classify patients into good (group A) or poor (group B) glycemic control groups. We applied multivariate strategies of analysis to control for other potential predictors of PD-related infection. ♦ Results: Groups A and B differed significantly in age, dialysis vintage, use of insulin, and rate of Staphylococcus aureus carriage. Neither the incidence (0.60 episodes in group A vs 0.56 episodes in group B per patient-year) nor the time to a first peritoneal infection (median: 42 months vs 38 months) differed significantly between the study groups. In contrast, group B had a significantly higher incidence of catheter tunnel and exit-site infections (0.23 episodes vs 0.12 episodes per patient-year) and shorter time to a first infection episode (64 months vs 76 months, p = 0.004). The difference persisted in multivariate analysis (adjusted hazard ratio: 2.65; 95% confidence interval: 1.13 to 6.05; p = 0.013). We observed no differences between the study groups in the spectrum of causative organisms or in the outcomes of PD-related infections. ♦ Conclusions: Poor glycemic control is a consistent predictor of subsequent risk of catheter tunnel and exit-site infection, but not of peritoneal infection, among diabetic patients starting PD therapy. PMID:23818005

Long-term reliable physically unclonable function based on oxide tunnel barrier breakdown on two-transistors two-magnetic-tunnel-junctions cell-based embedded spin transfer torque magnetoresistive random access memory

NASA Astrophysics Data System (ADS)

Takaya, Satoshi; Tanamoto, Tetsufumi; Noguchi, Hiroki; Ikegami, Kazutaka; Abe, Keiko; Fujita, Shinobu

2017-04-01

Among the diverse applications of spintronics, security for internet-of-things (IoT) devices is one of the most important. A physically unclonable function (PUF) with a spin device (spin transfer torque magnetoresistive random access memory, STT-MRAM) is presented. Oxide tunnel barrier breakdown is used to realize long-term stability for PUFs. A secure PUF has been confirmed by evaluating the Hamming distance of a 32-bit STT-MRAM-PUF fabricated using 65 nm CMOS technology.

Long-term results from the Contura multilumen balloon breast brachytherapy catheter phase 4 registry trial.

PubMed

Cuttino, Laurie W; Arthur, Douglas W; Vicini, Frank; Todor, Dorin; Julian, Thomas; Mukhopadhyay, Nitai

2014-12-01

To describe the long-term outcomes from a completed, multi-institutional phase 4 registry trial using the Contura multilumen balloon (CMLB) breast brachytherapy catheter to deliver accelerated partial breast irradiation (APBI) in patients with early-stage breast cancer. Three hundred forty-two evaluable patients were enrolled by 23 institutions between January 2008 and February 2011. All patients received 34 Gy in 10 fractions, delivered twice daily. Rigorous target coverage and normal tissue dose constraints were observed. The median follow-up time was 36 months (range, 1-54 months). For the entire patient cohort of 342 patients, 10 patients experienced an ipsilateral breast tumor recurrence (IBTR). Eight of these IBTR were classified as true recurrences/marginal miss (TRMM), and 2 were elsewhere failures (EF). Local recurrence-free survival was 97.8% at 3 years. For the entire cohort, 88% of patients had good to excellent overall cosmesis. The overall incidence of infection was 8.5%. Symptomatic seroma was reported in only 4.4% of patients. A separate analysis was performed to determine whether improved outcomes would be observed for patients treated at high-volume centers with extensive brachytherapy experience. Three IBTR were observed in this cohort, only 1 of which was classified as a TRMM. Local recurrence-free survival at high-volume centers was 98.1% at 3 years. Overall cosmetic outcome and toxicity were superior in patients treated at high-volume centers. In these patients, 95% had good to excellent overall cosmesis. Infection was observed in only 2.9% of patients, and symptomatic seroma was reported in only 1.9%. Use of the CMLB for APBI delivery is associated with acceptable long-term local control and toxicity. Local recurrence-free survival was 97.8% at 3 years. Significant (grade 3) toxicity was uncommon, and no grade 4 toxicity was observed. Treatment at high-volume centers was associated with decreased late toxicity. Copyright © 2014 Elsevier Inc

Long-Term Results From the Contura Multilumen Balloon Breast Brachytherapy Catheter Phase 4 Registry Trial

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

Cuttino, Laurie W., E-mail: lcuttino@mcvh-vcu.edu; Arthur, Douglas W.; Vicini, Frank

2014-12-01

Purpose: To describe the long-term outcomes from a completed, multi-institutional phase 4 registry trial using the Contura multilumen balloon (CMLB) breast brachytherapy catheter to deliver accelerated partial breast irradiation (APBI) in patients with early-stage breast cancer. Methods and Materials: Three hundred forty-two evaluable patients were enrolled by 23 institutions between January 2008 and February 2011. All patients received 34 Gy in 10 fractions, delivered twice daily. Rigorous target coverage and normal tissue dose constraints were observed. Results: The median follow-up time was 36 months (range, 1-54 months). For the entire patient cohort of 342 patients, 10 patients experienced an ipsilateral breast tumor recurrencemore » (IBTR). Eight of these IBTR were classified as true recurrences/marginal miss (TRMM), and 2 were elsewhere failures (EF). Local recurrence-free survival was 97.8% at 3 years. For the entire cohort, 88% of patients had good to excellent overall cosmesis. The overall incidence of infection was 8.5%. Symptomatic seroma was reported in only 4.4% of patients. A separate analysis was performed to determine whether improved outcomes would be observed for patients treated at high-volume centers with extensive brachytherapy experience. Three IBTR were observed in this cohort, only 1 of which was classified as a TRMM. Local recurrence-free survival at high-volume centers was 98.1% at 3 years. Overall cosmetic outcome and toxicity were superior in patients treated at high-volume centers. In these patients, 95% had good to excellent overall cosmesis. Infection was observed in only 2.9% of patients, and symptomatic seroma was reported in only 1.9%. Conclusion: Use of the CMLB for APBI delivery is associated with acceptable long-term local control and toxicity. Local recurrence-free survival was 97.8% at 3 years. Significant (grade 3) toxicity was uncommon, and no grade 4 toxicity was observed. Treatment at high-volume centers was

Thrombotic complications of central venous catheters in cancer patients.

PubMed

Kuter, David J

2004-01-01

Central venous catheters (CVCs), such as the tunneled catheters and the totally implanted ports, play a major role in general medicine and oncology. Aside from the complications (pneumothorax, hemorrhage) associated with their initial insertion, all of these CVCs are associated with the long-term risks of infection and thrombosis. Despite routine flushing with heparin or saline, 41% of CVCs result in thrombosis of the blood vessel, and this markedly increases the risk of infection. Only one-third of these clots are symptomatic. Within days of insertion, almost all CVCs are coated with a fibrin sheath, and within 30 days, most CVC-related thrombi arise. Aside from reducing the function of the catheter, these CVC-related thrombi can cause postphlebitic syndrome in 15%-30% of cases and pulmonary embolism in 11% (only half of which are symptomatic). Risk factors for CVC thrombosis include the type of malignancy, type of chemotherapy, type of CVC, and locations of insertion site and catheter tip, but not inherited thrombophilic risk factors. Efforts to reduce CVC thrombosis with systemic prophylactic anticoagulation with low-molecular-weight heparin have failed. Low-dose warfarin prophylaxis remains controversial; all studies are flawed, with older studies, but not newer ones, showing benefit. Currently, less than 10% of patients with CVCs receive any systemic prophylaxis. Although its general use cannot be recommended, low-dose warfarin may be a low-risk treatment in patients with good nutrition and adequate hepatic function. Clearly, additional studies are required to substantiate the prophylactic use of low-dose warfarin. Newer anticoagulant treatments, such as pentasaccharide and direct thrombin inhibitors, need to be explored to address this major medical problem.

[The role of the uretral catheter in the development of catheter- related urinary tract infection].

PubMed

Vasilyev, A O; Govorov, A V; Shiryaev, A A; Pushkar, D Yu

2017-12-01

The most common source of nosocomial infection is the urinary tract, especially if they it is drained with a urethral catheter. Catheter-associated urinary tract infections account for at least 80% of all complicated urinary tract infections and are the most common type of hospital-acquired infection. Intestinal microflora plays the leading role in the pathogenesis of catheter-associated urinary tract infections, whereas the most important risk factor for their development is the long duration of urinary catheter drainage. In the case of short-term and intermittent catheterization, routine antibiotic prophylaxis is not required, but if a patient develops clinically significant infection, antibiotic therapy is required followed by definitive therapy based on culture. Urethral catheters coated with antimicrobial substances and anti-inflammatory agents can significantly reduce the adhesion and migration of bacteria, thereby reducing the incidence of urinary tract infections. Despite this, the incidence of catheter-associated infection remains high. We have reviewed recent literature related to catheter-associated urinary tract infections and the best means of preventing this condition.

[Complications associated to central venous catheters in hematology patients].

PubMed

García-Gabás, Carmen; Castillo-Ayala, Ana; Hinojo-Marín, Begoña; Muriel-Abajo, M Ángeles; Gómez-Gutiérrez, Isabel; de Mena-Arenas, Ana M; Rodríguez-Gonzalo, Ana; Chao-Lozano, Cristina; García-Menéndez, Carmen; Madroñero-Agreda, M Antonia

2015-01-01

To discover the incidence of central venous catheters (tunnelled, subcutaneous and PICC) in patients with onco-hematological conditions, hospitalized in the Hematology or Transplantations of Hematopoietic Stem Cells Units, in two tertiary care hospitals. A cross-sectional, descriptive study form was developed in order to gather sociodemographic, clinical data as well as complications and follow-up of the care protocol. Each catheter was assigned a correlative identification number. Information was collected on 366 catheters: 185 in the University Hospital Ramón y Cajal (HURYC), 80 tunnelled, 40 subcutaneous venous access and 65 PICC, and 181 in the University Hospital Gregorio Marañón (HUGM), 101 tunnelled and 80 subcutaneous venous access. Major complications in the tunnellized were infections (13.7% in HURYC vs. 6.8% in HUGM - p<0.001) and occlusions (at least once in 3.8% vs. 21.8%). In subcutaneous venous access, infections were confirmed in 5% in HURYC vs. 1.2% in HUGM. There were occlusions at least once in 10% in HUGM and no other significant complications were detected. Regarding PICC, information was only collected in HURYC, where complications were phlebitis 10.8%, thrombosis 7.7%, confirmed or suspected infection 4.6%, occlusion at least once 7.7%. Differences between hospitals with regard to major complications, infection and occlusion may be related to different care protocol. We need to stress the high incidence of phlebitis and thrombosis in PICC catheters, compared with data of lower incidence of other papers. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

Catheter-associated bloodstream infections in pediatric hematology-oncology patients: factors associated with catheter removal and recurrence.

PubMed

Adler, Amos; Yaniv, Isaac; Solter, Ester; Freud, Enrique; Samra, Zmira; Stein, Jerry; Fisher, Salvador; Levy, Itzhak

2006-01-01

The aims of this study were to analyze the factors associated with antibiotic failure leading to tunneled central venous catheter (CVC) removal during catheter-associated bloodstream infections (CABSIs) and with recurrence and reinfection in children with cancer. All cases of CABSI in patients attending the Department of Pediatric Hematology-Oncology between November 2000 and November 2003 were reviewed. A total of 207 episodes of CABSI, including multiple episodes involving the same catheter, were identified in 146 of 410 tunneled CVCs (167 Hickman, 243 implantable ports). The most common organism isolated was coagulase-negative Staphylococcus (CONS). The CVC was removed in 96 (46%) episodes. Hypotension, persistent bacteremia, previous stem cell transplantation, multiple CABSIs in the same CVC, exit-site infection, inappropriate empiric antibiotic therapy, and Candida infection were all significantly associated with increased risk of catheter removal (P < 0.05, odds ratios 7.81, 1.14, 2.22, 1.93, 3.04, 2.04 and 24.53, respectively). There were 12 episodes of recurrent infection, all except 1 caused by CONS (odds ratio 20.5, P = 0.006). Inappropriate empiric therapy, especially in implantable ports, was the only mutable risk factor for antibiotic failure. Because CONS was the predominant isolate in these devices, adding glycopeptides to the empiric therapy for suspected implantable-port CABSI might decrease the removal rate. This issue should be explored in future controlled trials.

Choline deficiency is associated with increased risk for venous catheter thrombosis.

PubMed

Buchman, Alan L; Ament, Marvin E; Jenden, Donald J; Ahn, Chul

2006-01-01

Patients with intestinal failure who require long-term parenteral nutrition (PN) develop catheter thrombosis as a complication. This patient group may also develop choline deficiency because of a defect in the hepatic transsulfuration pathway in the setting of malabsorption. This study was undertaken to determine whether choline deficiency is a risk factor for development of catheter thrombosis. Plasma free and phospholipid-bound choline concentrations were measured in a group of 41 patients that required long-term PN. Episodes of catheter thrombosis from onset of PN to the time of blood testing were recorded. Sixteen (39%) patients developed catheter thrombosis, and 5 of these had recurrent catheter thrombosis. Plasma free choline was 7.7 +/- 2.7 nmol/mL in patients with no history of catheter thrombosis and 6.2 +/- 1.7 nmol/mL in patients with previous catheter thrombosis (p = .076 by Wilcoxon rank-sum test). The partial correlation between plasma free choline concentration and the frequency of clots after controlling for catheter duration was r = -0.33 (p = .038). The relative risk for catheter thrombosis in subjects with a plasma free choline concentration <8 nmol/mL was 10.0, 95% confidence interval (1.134-88.167). Plasma phospholipid-bound choline concentration was 2191.7 +/- 679.0 nmol/mL in patients with previous catheter thrombosis and 2103.3 +/- 531.2 nmol/mL in patients without history of catheter thrombosis (p = NS). Choline deficiency is a significant risk factor for development of catheter thrombosis in patients with intestinal failure who require PN.

Magnetic Tunnel Junction Based Long-Term Short-Term Stochastic Synapse for a Spiking Neural Network with On-Chip STDP Learning

NASA Astrophysics Data System (ADS)

Srinivasan, Gopalakrishnan; Sengupta, Abhronil; Roy, Kaushik

2016-07-01

Spiking Neural Networks (SNNs) have emerged as a powerful neuromorphic computing paradigm to carry out classification and recognition tasks. Nevertheless, the general purpose computing platforms and the custom hardware architectures implemented using standard CMOS technology, have been unable to rival the power efficiency of the human brain. Hence, there is a need for novel nanoelectronic devices that can efficiently model the neurons and synapses constituting an SNN. In this work, we propose a heterostructure composed of a Magnetic Tunnel Junction (MTJ) and a heavy metal as a stochastic binary synapse. Synaptic plasticity is achieved by the stochastic switching of the MTJ conductance states, based on the temporal correlation between the spiking activities of the interconnecting neurons. Additionally, we present a significance driven long-term short-term stochastic synapse comprising two unique binary synaptic elements, in order to improve the synaptic learning efficiency. We demonstrate the efficacy of the proposed synaptic configurations and the stochastic learning algorithm on an SNN trained to classify handwritten digits from the MNIST dataset, using a device to system-level simulation framework. The power efficiency of the proposed neuromorphic system stems from the ultra-low programming energy of the spintronic synapses.

Magnetic Tunnel Junction Based Long-Term Short-Term Stochastic Synapse for a Spiking Neural Network with On-Chip STDP Learning.

PubMed

Srinivasan, Gopalakrishnan; Sengupta, Abhronil; Roy, Kaushik

2016-07-13

Spiking Neural Networks (SNNs) have emerged as a powerful neuromorphic computing paradigm to carry out classification and recognition tasks. Nevertheless, the general purpose computing platforms and the custom hardware architectures implemented using standard CMOS technology, have been unable to rival the power efficiency of the human brain. Hence, there is a need for novel nanoelectronic devices that can efficiently model the neurons and synapses constituting an SNN. In this work, we propose a heterostructure composed of a Magnetic Tunnel Junction (MTJ) and a heavy metal as a stochastic binary synapse. Synaptic plasticity is achieved by the stochastic switching of the MTJ conductance states, based on the temporal correlation between the spiking activities of the interconnecting neurons. Additionally, we present a significance driven long-term short-term stochastic synapse comprising two unique binary synaptic elements, in order to improve the synaptic learning efficiency. We demonstrate the efficacy of the proposed synaptic configurations and the stochastic learning algorithm on an SNN trained to classify handwritten digits from the MNIST dataset, using a device to system-level simulation framework. The power efficiency of the proposed neuromorphic system stems from the ultra-low programming energy of the spintronic synapses.

Does the Implantation Technique for Totally Implantable Venous Access Ports (TIVAPs) Influence Long-Term Outcome?

PubMed

Biacchi, Daniele; Sammartino, Paolo; Sibio, Simone; Accarpio, Fabio; Cardi, Maurizio; Sapienza, Paolo; De Cesare, Alessandro; Atta, Joseph Maher Fouad; Impagnatiello, Alessio; Di Giorgio, Angelo

2016-02-01

Totally implantable venous access ports (TIVAP) are eventually explanted for various reasons, related or unrelated to the implantation technique used. Having more information on long-term explantation would help improve placement techniques. From a series of 1572 cancer patients who had TIVAPs implanted in our center with the cutdown technique or Seldinger technique, we studied the 542 patients who returned to us to have their TIVAP explanted after 70 days or more. As outcome measures we distinguished between TIVAPs explanted for long-term complications (infection, catheter-, reservoir-, and patient-related complications) and TIVAPs no longer needed. Univariate and multivariate analyses were run to investigate the reasons for explantation and their possible correlation with implantation techniques. The most common reason for explantation was infection (47.6 %), followed by catheter-related (20.8 %), patient-related (14.7 %), and reservoir-related complications (4.7 %). In the remaining 12.2 % of cases, the TIVAP was explanted complication free after the planned treatments ended. Infection correlated closely with longer TIVAP use. Univariate and multivariate analyses identified the Seldinger technique as a major risk factor for venous thrombosis and catheter dislocation. The need for long-term TIVAP explantation in about one-third of cancer patients is related to the implantation techniques used.

Surgical Placement of Catheters for Long-term Cardiovascular Exercise Testing in Swine

PubMed Central

van Duin, Richard W B; Verzijl, Annemarie; Reiss, Irwin K; Duncker, Dirk J; Merkus, Daphne

2016-01-01

This protocol describes the surgical procedure to chronically instrument swine and the procedure to exercise swine on a motor-driven treadmill. Early cardiopulmonary dysfunction is difficult to diagnose, particularly in animal models, as cardiopulmonary function is often measured invasively, requiring anesthesia. As many anesthetic agents are cardiodepressive, subtle changes in cardiovascular function may be masked. In contrast, chronic instrumentation allows for measurement of cardiopulmonary function in the awake state, so that measurements can be obtained under quiet resting conditions, without the effects of anesthesia and acute surgical trauma. Furthermore, when animals are properly trained, measurements can also be obtained during graded treadmill exercise. Flow probes are placed around the aorta or pulmonary artery for measurement of cardiac output and around the left anterior descending coronary artery for measurement of coronary blood flow. Fluid-filled catheters are implanted in the aorta, pulmonary artery, left atrium, left ventricle and right ventricle for pressure measurement and blood sampling. In addition, a 20 G catheter is positioned in the anterior interventricular vein to allow coronary venous blood sampling. After a week of recovery, swine are placed on a motor-driven treadmill, the catheters are connected to pressure and flow meters, and swine are subjected to a five-stage progressive exercise protocol, with each stage lasting 3 min. Hemodynamic signals are continuously recorded and blood samples are taken during the last 30 sec of each exercise stage. The major advantage of studying chronically instrumented animals is that it allows serial assessment of cardiopulmonary function, not only at rest but also during physical stress such as exercise. Moreover, cardiopulmonary function can be assessed repeatedly during disease development and during chronic treatment, thereby increasing statistical power and hence limiting the number of animals

Long-term venous access using a subcutaneous implantable drug delivery system.

PubMed Central

Soo, K. C.; Davidson, T. I.; Selby, P.; Westbury, G.

1985-01-01

To facilitate long-term venous access in patients receiving chemotherapy, a subcutaneous totally implantable system (Port-a-Cath, Phamacia) has been used in 14 patients. The method of implantation and the advantages over conventional central venous catheters are discussed. The expense of the system necessitates careful patient selection. PMID:4037644

Tarsal tunnel syndrome in a patient on long-term peritoneal dialysis: case report.

PubMed

Ozdemir, Ozgür; Calişaneller, Tarkan; Sönmez, Erkin; Altinörs, Nur

2007-10-01

Tarsal tunnel syndrome (TTS) is defined as the entrapment of the posterior tibial nerve in the tarsal tunnel of the ankle. The etiologies of tarsal tunnel syndrome are mainly the presence of a ganglion, osseous prominence with tarsal bone coalition, trauma, varicose veins, neurinoma, hypertrophy of the flexor retinaculum, or systemic disease (rheumatoid arthritis, ankylosing spondylitis). However, no specific cause can be identified in some cases. Patients with chronic renal failure tend to develop peripheral nerve entrapment and carpal tunnel syndrome is the best-known peripheral entrapment neuropathy among them. Contrary to carpal tunnel syndrome, tarsal tunnel syndrome is observed less frequently in chronic renal failure patients. The common presenting symptoms of TTS are paresthesias and/or pain in the plantar side of the foot. Motor symptoms are rarely detected. Diagnosis is made primarily by electroneuromyographic studies and physical examination. Surgery is the treatment of choice and the outcome is generally favourable. In this report, we present a patient with tarsal tunnel syndrome complicating peritoneal dialysis.

Pulmonary embolism as a complication of long-term total parenteral nutrition.

PubMed

Mailloux, R J; DeLegge, M H; Kirby, D F

1993-01-01

Although much has been written concerning the complications of long-term total parenteral nutrition, little or no mention of pulmonary embolism is made in the literature. We present two patients maintained on home total parenteral nutrition who suffered pulmonary emboli, one while receiving standard heparin therapy. No potential source other than their indwelling total parenteral nutrition catheter was identified. Studies have revealed catheter-related thrombosis in up to 50% of patients with indwelling central venous catheters. Although early surgical literature suggested that upper extremity deep vein thromboses rarely embolize, more recent investigations have proven this false. In fact, the risk of pulmonary emboli appeared to be greatest in those thrombi that were catheter related. Because of this risk, we suggest a hypercoaguable work-up in any patient with a history of recurrent thrombosis. Heparin is central to the current preventive regimens; however, further study is needed to determine the most efficacious dose. Future development of less thrombogenic catheters will also be of assistance. Thrombolytic agents currently have an expanding role in the treatment of thrombotic complications. Whether they will have a future role in prevention remains unknown.

Types of urethral catheters for management of short-term voiding problems in hospitalized adults: a short version Cochrane review.

PubMed

Schumm, K; Lam, T B L

2008-01-01

Urinary tract infection (UTI) is the most common hospital acquired infection. The major associated cause is indwelling urinary catheters. Currently there are many types of catheters available. A variety of specialized urethral catheters have been designed to reduce the risk of infection. These include antiseptic impregnated catheters and antibiotic impregnated catheters. Other issues that should be considered when choosing a catheter are ease of use, comfort and cost. The primary objective of this review was to determine the effect of type of indwelling urethral catheter on the risk of urinary tract infection in adults who undergo short-term urinary catheterization. We searched the Specialized Trials Register of the Cochrane Incontinence Group (searched September 11, 2007). We also examined the bibliographies of relevant articles and contacted catheter manufacturer representatives for trials. All randomized and quasi-randomized trials comparing types of indwelling urinary catheters for short-term catheterization in hospitalized adults. Short-term catheterization was defined as up to and including 14 days, or other temporary short-term use as defined by the trialists (for example <21 days with data time points at 7-day intervals). Data were extracted by one reviewer and independently verified by a second reviewer for both the original review and for the update. Disagreements were resolved by discussion. Data were processed as described in the Cochrane Handbook. Where data in trials were not fully reported, clarification was sought directly from the trialists (secondary sources were used to confirm results of one trial). Twenty-three trials met the inclusion criteria involving 5,236 hospitalized adults in 22 parallel group trials and 27,878 adults in one large cluster-randomized cross-over trial. The antiseptic catheters were either impregnated with silver oxide or silver alloy. Silver oxide catheters were not associated with a statistically significant reduction in

Long term indwelling urethral catheterisation for congenital neuropathic bladder.

PubMed Central

Rickwood, A M; Philp, N H; Thomas, D G

1983-01-01

Long term urethral catheterisation remains an important and effective method of achieving dryness and maintaining renal function in children with congenital neuropathic bladders. Those most likely to require an indwelling catheter are girls who are severely disabled because of myelomeningocele. The management of such catheterisation and its consequences, in the light of our experience with a 100 children treated over a 12 year period, is described. Images Fig. 2 PMID:6847235

The Role of Astro-Geodetic in Precise Guidance of Long Tunnels

NASA Astrophysics Data System (ADS)

Mirghasempour, M.; Jafari, A. Y.

2015-12-01

One of prime aspects of surveying projects is guidance of paths of a long tunnel from different directions and finally ending all paths in a specific place. This kind of underground surveying, because of particular condition, has some different points in relation to the ground surveying, including Improper geometry in underground transverse, low precise measurement in direction and length due to condition such as refraction, distinct gravity between underground point and corresponding point on the ground (both value and direction of gravity) and etc. To solve this problems, astro-geodetic that is part of geodesy science, can help surveying engineers. In this article, the role of astronomy is defined in two subjects: 1- Azimuth determination of directions from entrance and exit nets of tunnel and also calibration of gyro-theodolite to use them in Underground transvers: By astronomical methods, azimuth of directions can be determine with an accuracy of 0.5 arcsecond, whereas, nowadays, no gyroscope can measure the azimuth in this accuracy; For instance, accuracy of the most precise gyroscope (Gyromat 5000) is 1.2 cm over a distance of one kilometre (2.4 arcsecond). Furthermore, the calibration methods that will be mention in this article, have significance effects on underground transverse. 2- Height relation between entrance point and exit point is problematic and time consuming; For example, in a 3 km long tunnel ( in Arak- Khoram Abad freeway), to relate entrance point to exit point, it is necessary to perform levelling about 90 km. Other example of this boring and time consuming levelling is in Kerman tunnel. This tunnel is 36 km length, but to transfer the entrance point height to exit point, 150 km levelling is needed. According to this paper, The solution for this difficulty is application of astro-geodetic and determination of vertical deflection by digital zenith camera system TZK2-D. These two elements make possible to define geoid profile in terms of

A prospective interventional study to examine the effect of a silver alloy and hydrogel-coated catheter on the incidence of catheter-associated urinary tract infection.

PubMed

Chung, P Hy; Wong, C Wy; Lai, C Kc; Siu, H K; Tsang, D Nc; Yeung, K Y; Ip, D Km; Tam, P Kh

2017-06-01

Catheter-associated urinary tract infection is a major hospital-acquired infection. This study aimed to analyse the effect of a silver alloy and hydrogel-coated catheter on the occurrence of catheter-associated urinary tract infection. This was a 1-year prospective study conducted at a single centre in Hong Kong. Adult patients with an indwelling urinary catheter for longer than 24 hours were recruited. The incidence of catheter-associated urinary tract infection in patients with a conventional latex Foley catheter without hydrogel was compared with that in patients with a silver alloy and hydrogel-coated catheter. The most recent definition of urinary tract infection was based on the latest surveillance definition of the National Healthcare Safety Network managed by Centers for Disease Control and Prevention. A total of 306 patients were recruited with a similar ratio between males and females. The mean (standard deviation) age was 81.1 (10.5) years. The total numbers of catheter-days were 4352 and 7474 in the silver-coated and conventional groups, respectively. The incidences of catheter-associated urinary tract infection per 1000 catheter-days were 6.4 and 9.4, respectively (P=0.095). There was a 31% reduction in the incidence of catheter-associated urinary tract infection per 1000 catheter-days in the silver-coated group. Escherichia coli was the most commonly involved pathogen (36.7%) of all cases. Subgroup analysis revealed that the protective effect of silver-coated catheter was more pronounced in long-term users as well as female patients with a respective 48% (P=0.027) and 42% (P=0.108) reduction in incidence of catheter-associated urinary tract infection. The mean catheterisation time per person was the longest in patients using a silver-coated catheter (17.0 days) compared with those using a conventional (10.8 days) or both types of catheter (13.6 days) [P=0.01]. Silver alloy and hydrogel-coated catheters appear to be effective in preventing catheter

Change in Vascular Access and Hospitalization Risk in Long-Term Hemodialysis Patients

PubMed Central

Wang, Weiling; Lazarus, J. Michael; Hakim, Raymond M.

2010-01-01

Background and objectives: Conversion from central venous catheters to a graft or a fistula is associated with lower mortality risk in long-term hemodialysis (HD) patients; however, a similar association with hospitalization risk remains to be elucidated. Design, setting, participants, & measurements: We conducted a prospective observational study all maintenance in-center HD patients who were treated in Fresenius Medical Care, North America legacy facilities; were alive on January 1, 2007; and had baseline laboratory data from December 2006. Access conversion (particularly from a catheter to a fistula or a graft) during the 4-month period from January 1 through April 30, 2007, was linked using Cox models to hospitalization risk during the succeeding 1-year follow-up period (until April 30, 2008). Results: The cohort (N = 79,545) on January 1, 2007 had 43% fistulas, 29% catheters, and 27% grafts. By April 30, 2007, 70,852 patients were still on HD, and among 19,792 catheters initially, only 10.3% (2045 patients) converted to either a graft or a fistula. With catheters as reference, patients who converted to grafts/fistulas had similar adjusted hazard ratios (0.69) as patients on fistulas (0.71), while patients with fistulas/grafts who converted to catheters did worse (1.22), all P < 0.0001. Conclusions: Catheters remain associated with the greatest hospitalization risk. Conversion from a catheter to either graft or fistula had significantly lower hospitalization risk relative to keeping the catheter. Prospective studies are needed to determine whether programs that reduce catheters will decrease hospitalization risk in HD patients. PMID:20884778

Videolaparoscopic Catheter Placement Reduces Contraindications to Peritoneal Dialysis

PubMed Central

Santarelli, Stefano; Zeiler, Matthias; Monteburini, Tania; Agostinelli, Rosa Maria; Marinelli, Rita; Degano, Giorgio; Ceraudo, Emilio

2013-01-01

♦ Background: Videolaparoscopy is considered the reference method for peritoneal catheter placement in patients with previous abdominal surgery. The placement procedure is usually performed with at least two access sites: one for the catheter and the second for the laparoscope. Here, we describe a new one-port laparoscopic procedure that uses only one abdominal access site in patients not eligible for laparotomic catheter placement. ♦ Method: We carried out one-port laparoscopic placement in 21 patients presenting contraindications to blind surgical procedures because of prior abdominal surgery. This technique consists in the creation of a single mini-laparotomy access through which laparoscopic procedures and placement are performed. The catheter, rectified by an introducer, is inserted inside the port. Subsequently, the port is removed, leaving the catheter in pelvic position. The port is reintroduced laterally to the catheter, confirming or correcting its position. Laparotomic placement was performed in a contemporary group of 32 patients without contraindications to blind placement. Complications and long-term catheter outcome in the two groups were evaluated. ♦ Results: Additional interventions during placement were necessary in 12 patients of the laparoscopy group compared with 5 patients of the laparotomy group (p = 0.002). Laparoscopy documented adhesions in 13 patients, with need for adhesiolysis in 6 patients. Each group had 1 intraoperative complication: leakage in the laparoscopy group, and intestinal perforation in the laparotomy group. During the 2-year follow-up period, laparoscopic revisions had to be performed in 6 patients of the laparoscopy group and in 5 patients of the laparotomy group (p = 0.26). The 1-year catheter survival was similar in both groups. Laparoscopy increased by 40% the number of patients eligible to receive peritoneal dialysis. ♦ Conclusions: Videolaparoscopy placement in patients not eligible for blind surgical

Tip Design of Hemodialysis Catheters Influences Thrombotic Events and Replacement Rate.

PubMed

Petridis, C; Nitschke, M; Lehne, W; Smith, E; Goltz, J P; Lehnert, H; Meier, M

2017-02-01

Central venous tunnelled hemodialysis catheters (CVTC) are used for initial vascular access in patients with renal failure. Tip design of the CVTC may play an important role in catheter function and complication rates, influencing adequate hemodialysis treatment of these patients. This prospective, observational cohort study compared the function and complication rates of two CVTCs in patients with end stage renal disease (ESRD) within a follow-up period of 24 months. The study included patients with ESRD who received either a CVTC with a split tip (ST) or a shotgun tip (SG). All patients underwent dialysis within 24 h of intervention. Blood flow was documented initially (Qb 0 ) and was followed up after 6 (Qb 6 ), 12 (Qb 12 ), and 24 (Qb 24 ) months. Analysis of blood flow and complication rates within the follow-up period was performed by questionnaires. In total, 185 patients were included, of whom 93 received a ST CVTC and 92 a SG CVTC. Baseline parameters did not differ significantly between groups. CVTC blood flow was not significantly different between the two devices. Thrombolytic therapy with Alteplase was used significantly more often in the ST group (29%) than in the SG group (16%) (p < 0.05). The CVTC replacement rate was significantly higher in the ST group (19.3%) compared with the SG group (8.7%) (p < 0.05). The tip design of CVTC (split or shotgun) appears to be irrelevant for long-term blood flow during dialysis treatment. However, patients may benefit from SG catheters over ST catheters where replacement rates and thrombolytic treatment are concerned. Copyright © 2016 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Light intensity distribution optimization for tunnel lamps in different zones of a long tunnel.

PubMed

Lai, Wei; Liu, Xianming; Chen, Weimin; Lei, Xiaohua; Cheng, Xingfu

2014-09-22

The light distributions in different tunnel zones have different requirements in order to meet the driver's visual system. In this paper, the light intensity distributions of tunnel lamps in different zones of a long tunnel are optimized separately. A common nonlinear optimization approach is proposed to minimize the consuming power as well as satisfy the luminance and glare requirements both on the road surface and on the wall set by International Commission on Illumination (CIE). Compared with that of the reported linear optimization method, the optimization model can save energy from 11% to 57.6% under the same installation conditions.

Washout policies in long-term indwelling urinary catheterisation in adults.

PubMed

Hagen, Suzanne; Sinclair, Lesley; Cross, Stephen

2010-03-17

People requiring long-term bladder draining with an indwelling catheter can experience catheter blockage. Regimens involving different solutions can be used to washout catheters with the aim of preventing blockage. To determine if certain washout regimens are better than others in terms of effectiveness, acceptability, complications, quality of life and economics for the management of long-term indwelling urinary catheterisation in adults. We searched the Cochrane Incontinence Group Specialised Trials Register, MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, CINAHL and EMBASE (searches last updated April 2009). Additionally, we examined all reference lists of identified trials. All randomised and quasi-randomised trials comparing catheter washout policies (e.g. washout versus no washout, different washout solutions, frequency, duration, volume, concentration, method of administration) in adults (16 years and above) in any setting (i.e. hospital, nursing/residential home, community) with an indwelling urethral or suprapubic catheter for more than 28 days. Data were extracted by three reviewers independently and compared. Disagreements were resolved by discussion. Data were processed as described in the Cochrane Handbook. If the data in trials were not fully reported, clarification was sought from the authors. For categorical outcomes, the numbers reporting an outcome were related to the numbers at risk in each group to derive an risk ratio (RR). For continuous outcomes, means and standard deviations were used to derive weighted mean differences (WMD). No meta-analysis of study results was possible. Five trials met the inclusion criteria involving 242 patients (132 completed) in two cross-over and three parallel-group randomised controlled trials. Only three of the eight pre-stated comparisons were addressed in these trials. Some trials addressed more than one comparison (e.g. washout versus no washout and one type of washout solution versus another). The

S-Nitroso-N-acetylpenicillamine (SNAP) Impregnated Silicone Foley Catheters: A Potential Biomaterial/Device To Prevent Catheter-Associated Urinary Tract Infections

PubMed Central

2016-01-01

Urinary Foley catheters are utilized for management of hospitalized patients and are associated with high rates of urinary tract infections (UTIs). Nitric oxide (NO) potently inhibits microbial biofilm formation, which is the primary cause of catheter associated UTIs (CAUTIs). Herein, commercial silicone Foley catheters are impregnated via a solvent swelling method with S-nitroso-N-acetyl-D-penicillamine (SNAP), a synthetic NO donor that exhibits long-term NO release and stability when incorporated into low water-uptake polymers. The proposed catheters generate NO surface-fluxes >0.7 × 10–10 mol min–1 cm–2 for over one month under physiological conditions, with minimal SNAP leaching. These biomedical devices are demonstrated to significantly decrease formation of biofilm on the surface of the catheter tubings over 3, 7, and 14 day periods by microbial species (Staphylococcus epidermidis and Proteus mirabilis) commonly causing CAUTIs. Toxicity assessment demonstrates that the SNAP-impregnated catheters are fully biocompatible, as extracts of the catheter tubings score 0 on a 3-point grading scale using an accepted mouse fibroblast cell-line toxicity model. Consequently, SNAP-impregnated silicone Foley catheters can likely provide an efficient strategy to greatly reduce the occurrence of nosocomial CAUTIs. PMID:26462294

[Catheter occlusion and venous thrombosis prevention and incidence in adult home parenteral nutrition (HPN) programme patients].

PubMed

Puiggròs, C; Cuerda, C; Virgili, N; Chicharro, M L; Martínez, C; Garde, C; de Luis, D

2012-01-01

In adult home parenteral nutrition (HPN) programme patients up to now no evidence-based recommendations exist on the central venous catheter maintenance nor venous thrombosis prevention. The use of heparin flushes could be linked with long term complications, besides, anticoagulants use is controversial. To be aware of the usual maintenance practice for HPN central venous catheters, catheter occlusion and related venous thrombosis incidence in our country. Retrospective study of active HPN patients older than 18 years registered by the NADYA- SENPE working group until November 2008. 49 patients were registered (16 males and 33 females), with an average age of 52.1 ± 13.9 years, belonging to 6 hospitals. HPN length was 57.4 ± 73.3 months with 5.8 ± 1.8 PN days a week. The most frequent pathologies were actinic enteritis, intestinal motility disorders and mesenteric ischemia (20.4% each), and neoplasm (16.3%). The reason for HPN provision was short bowel syndrome (49.0%), and intestinal obstruction (28.6%). Neoplasm (16.3%), thrombotic diathesis, thromboembolic syndrome and bed rest (6.1% each) were the main venous thrombosis adjuvant factors. Tunnelled catheters were used in 77.6% of patients, with implanted port-catheters in the remainder. Maintenance of the line was done with saline solution flushes (28.6%) and different concentrations of heparin solutions (69.4%). When heparin was used, it was removed before PN infusion in 63.3% of patients. Catheter occlusion and venous thrombotic events rates were 0.061/10³ and 0.115/10³ HPN days respectively. Eleven patients (22.4%) were treated with anticoagulant drugs due to previous episodes of venous thrombosis or pulmonary embolism. [corrected] The incidence of catheter related thrombotic complications incidence is low in this group of patients on HPN. There is a great variety of practices focused on the prevention of both: line occlusion and catheter related venous thrombosis. In conclusion, it would be necessary to

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.

Long-term Outcome of Peripherally Implanted Venous Access Ports in the Forearm in Female Cancer Patients

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

Klösges, Laura, E-mail: l.kloesges@uni-bonn.de; Meyer, Carsten, E-mail: carsten.meyer@ukb.uni-bonn.de; Boschewitz, Jack, E-mail: jack.boschewitz@ukb.uni-bonn.de

PurposeThe aim of this retrospective study was to analyze the long-term outcome of peripherally implanted venous access ports in the forearm at our institution in a female patient collective.MethodsBetween June 2002 and May 2011, a total of 293 female patients with an underlying malignancy had 299 forearm ports implanted in our interventional radiology suite. The mean age of the cohort was 55 ± 12 years (range 26–81 years). The majority of women suffered from breast (59.5 %) or ovarian cancer (28.1 %). Complications were classified as infectious complications, thrombotic and nonthrombotic catheter dysfunction (dislocation of the catheter or port chamber, fracture with/without embolization or kinking ofmore » the catheter, port occlusion), and others.ResultsWe analyzed a total of 90,276 catheter days in 248 port systems (47 patients were lost to follow-up). The mean device service interval was 364 days per catheter (range 8–2,132, median 223 days, CI 311–415, SD 404). Sixty-seven early (≤30 days from implantation) or late complications (>30 days) occurred during the observation period (0.74/1,000 catheter days). Common complications were port infection (0.18/1,000 days), thrombotic dysfunction (0.12/1,000 days), and skin dehiscence (0.12/1,000 days). Nonthrombotic dysfunction occurred in a total of 21 cases (0.23/1,000 days) and seemed to cumulate on the venous catheter entry site on the distal upper arm.ConclusionPeripherally implanted venous access ports in the forearm are a safe alternative to chest or upper-arm ports in female oncology patients. Special attention should be paid to signs of skin dehiscence and nonthrombotic dysfunction, especially when used for long-term treatment.« less

Acute and long term outcomes of catheter ablation using remote magnetic navigation for the treatment of electrical storm in patients with severe ischemic heart failure.

PubMed

Jin, Qi; Jacobsen, Peter Karl; Pehrson, Steen; Chen, Xu

2015-03-15

Catheter ablation with remote magnetic navigation (RMN) can offer some advantages compared to manual techniques. However, the relevant clinical evidence for how RMN-guided ablation affects electrical storm (ES) due to ventricular tachycardia (VT) in patients with severe ischemic heart failure (SIHF) is still limited. Forty consecutive SIHF patients (left ventricular ejection fraction, 21 ± 6.9%) presenting with ES underwent ablation using RMN. All the patients received implantable cardioverter-defibrillators (ICDs) either before or after ablation. Acute ablation success was defined as noninducibility of any sustained monophasic VT at the end of the procedure. Long-term analysis addressed VT recurrence, ICD therapies and all-cause death. ES was acutely suppressed by ablation in all patients. Acute ablation success was obtained in 32 of 40 (80%) patients. The procedure time and fluoroscopy time were 105 ± 27 min and 7.5 ± 4.8 min respectively. No major complications occurred during procedures. During a mean follow-up of 17.4 months, 19 patients (47.5%) remained free of VT recurrence. The percentage of patients receiving ICD shocks after ablation was lower than before ablation (30% vs 69%, P<0.01). The mean number of ICD shocks per individual per year was reduced from 4.3 before ablation to 1.9 after ablation (P<0.05). Ten patients died during follow-up. Acute catheter ablation with RMN is safe and effective to suppress ES in SIHF patients. RMN-guided catheter ablation can prevent VT recurrence and significantly reduce ICD shocks, suggesting that this strategy can be used as an alternative therapy for VT storm in SIHF patients with ICDs. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Long-term catheterization: current approaches in the diagnosis and treatment of port-related infections

PubMed Central

Bustos, Cesar; Aguinaga, Aitziber; Carmona-Torre, Francisco; Del Pozo, Jose Luis

2014-01-01

Since the first description in 1982, totally implanted venous access ports have progressively improved patients’ quality of life and medical assistance when a medical condition requires the use of long-term venous access. Currently, they are part of the standard medical care for oncohematologic patients. However, apart from mechanical and thrombotic complications, there are also complications associated with biofilm development inside the catheters. These biofilms increase the cost of medical assistance and extend hospitalization. The most frequently involved micro-organisms in these infections are gram-positive cocci. Many efforts have been made to understand biofilm formation within the lumen catheters, and to resolve catheter-related infection once it has been established. Apart from systemic antibiotic treatment, the use of local catheter treatment (ie, antibiotic lock technique) is widely employed. Many different antimicrobial options have been tested, with different outcomes, in clinical and in in vitro assays. The stability of antibiotic concentration in the lock solution once instilled inside the catheter lumen remains unresolved. To prevent infection, it is mandatory to perform hand hygiene before catheter insertion and manipulation, and to disinfect catheter hubs, connectors, and injection ports before accessing the catheter. At present, there are still unresolved questions regarding the best antimicrobial agent for catheter-related bloodstream infection treatment and the duration of concentration stability of the antibiotic solution within the lumen of the port. PMID:24570595

Spiculated Bladder Calculi: The Culprit for Repeated Catheter Failure

PubMed Central

Wek, C.; Fox, T. P.; Muir, G. H.

2013-01-01

We report on the case of a frustrated 90-year-old gentleman who was seen in the Accident and Emergency department for the third time in four days with failure of his long-term urethral catheter. He reported that the catheter simply “fell out” with the balloon deflated. On each occasion previously, the catheter had been reinserted in A&E and the patient discharged home. These repeated visits to A&E were understandably a source of much frustration for the patient and his family. On the third presentation, plain abdominal radiography demonstrated a large spiculated bladder calculus. PMID:23984173

Antifouling coating with controllable and sustained silver release for long-term inhibition of infection and encrustation in urinary catheters.

PubMed

Wang, Rong; Neoh, Koon Gee; Kang, En-Tang; Tambyah, Paul Anantharajah; Chiong, Edmund

2015-04-01

Urinary tract infections constitute a large proportion of nosocomial infections, and the urinary catheter is the most important predisposing factor. Encrustation induced by urease-producing uropathogens like Proteus mirabilis causes further complications. In the present work, a strategy for controllable and sustained release of silver over several weeks has been developed for combating bacterial infection and encrustation in urinary devices. Silver nanoparticles (AgNPs) were first immobilized on polydopamine (PDA) pre-treated silicone catheter surface and this was followed by another PDA coating. The number of AgNP-PDA bilayers could be manipulated to control the amount of silver loaded and its subsequent release. Poly(sulfobetaine methacrylate-co-acrylamide) was then grafted to provide an antifouling outer layer, and to ensure free diffusion of Ag from the surface. The micron-scale combination of an antifouling coating with AgNP-PDA bilayers reduced colonization of the urinary catheter by uropathogens by approximately two orders of magnitude. With one and two AgNP-PDA bilayers, the coated catheter could resist encrustation for 12 and 45 days, respectively, compared with approximately 6 days with the Dover™ silver-coated catheter. Such anti-infective and anti-encrustation catheters can potentially have a large impact on reducing patient morbidity and healthcare expenditure. © 2014 Wiley Periodicals, Inc.

Indwelling catheters and medical implants with FXIIIa inhibitors: a novel approach to the treatment of catheter and medical device-related infections

PubMed Central

Daneshpour, Nooshin; Collighan, Russell; Perrie, Yvonne; Lambert, Peter; Rathbone, Dan; Lowry, Deborah; Griffin, Martin

2013-01-01

Central venous catheters (CVCs) are being utilized with increasing frequency in intensive care and general medical wards. In spite of the extensive experience gained in their application, CVCs are related to the long-term risks of catheter sheath formation, infection and thrombosis (of the catheter or vessel itself) during catheterisation. Such CVC-related-complications are associated with increased morbidity, mortality, duration of hospitalisation and medical care cost [1]. The present study incorporates a novel group of Factor XIIIa (FXIIIa, plasma transglutaminase) inhibitors into a lubricious silicone elastomer in order to generate an optimized drug delivery system whereby a secondary sustained drug release profile occurs following an initial burst release for catheters and other medical devices. We propose that the incorporation of FXIIIa inhibitors into catheters, stents and other medical implant devices would reduce the incidence of catheter sheath formation, thrombotic occlusion and associated staphylococcal infection. This technique could be used as a local delivery system for extended release with an immediate onset of action for other poorly aqueous soluble compounds. PMID:23022540

Catheter-Related Bloodstream Infections in Patients on Emergent Hemodialysis.

PubMed

Rojas-Moreno, Christian A; Spiegel, Daniel; Yalamanchili, Venkata; Kuo, Elizabeth; Quinones, Henry; Sreeramoju, Pranavi V; Luby, James P

2016-03-01

This study had 2 objectives: (1) to describe the epidemiology of catheter-related bloodstream infections (CRBSI) in patients with end-stage renal disease (ESRD) who have no access to scheduled dialysis and (2) to evaluate whether a positive culture of the heparin-lock solution is associated with subsequent development of bacteremia. Retrospective observational cohort design for objective 1; and prospective cohort design for objective 2. The study was conducted in a 770-bed public academic tertiary hospital in Dallas, Texas. The participants were patients with ESRD undergoing scheduled or emergent hemodialysis. We reviewed the records of 147 patients who received hemodialysis between January 2011 and May 2011 and evaluated the rate of CRBSI in the previous 5 years. For the prospective study, we cultured the catheter heparin-lock solution in 62 consecutive patients between June 2012 and August 2012 and evaluated the incidence of CRBSI at 6 months. Of the 147 patients on emergent hemodialysis, 125 had a tunneled catheter, with a CRBSI rate of 2.61 per 1,000 catheter days. The predominant organisms were Gram-negative rods (GNR). In the prospective study, we found that the dialysis catheter was colonized more frequently in patients on emergent hemodialysis than in those on scheduled hemodialysis. Colonization with GNR or Staphylococcus aureus was associated with subsequent CRBSI at 6 months follow-up. Patients undergoing emergent hemodialysis via tunneled catheter are predisposed to Gram-negative CRBSI. Culturing the heparin-lock solution may predict subsequent episodes of CRBSI if it shows colonization with GNR or Staphylococcus aureus. Prevention approaches in this population need to be studied further.

Endoluminal dilatation for embedded hemodialysis catheters: A case-control study of factors associated with embedding and clinical outcomes

PubMed Central

Talreja, Hari; Ryan, Stephen Edward; Graham, Janet; Sood, Manish M.; Hadziomerovic, Adnan; Clark, Edward

2017-01-01

Background With the increasing frequency of tunneled hemodialysis catheter use there is a parallel increase in the need for removal and/or exchange. A small but significant minority of catheters become embedded or ‘stuck’ and cannot be removed by traditional means. Management of embedded catheters involves cutting the catheter, burying the retained fragment with a subsequent increased risk of infections and thrombosis. Endoluminal dilatation may provide a potential safe and effective technique for removing embedded catheters, however, to date, there is a paucity of data. Objectives 1) To determine factors associated with catheters becoming embedded and 2) to determine outcomes associated with endoluminal dilatation Methods All patients with endoluminal dilatation for embedded catheters at our institution since Jan. 2010 were included. Patients who had an embedded catheter were matched 1:3 with patients with uncomplicated catheter removal. Baseline patient and catheter characteristics were compared. Outcomes included procedural success and procedure-related infection. Logistic regression models were used to determine factors associated with embedded catheters. Results We matched 15 cases of embedded tunneled catheters with 45 controls. Among patients with embedded catheters, there were no complications with endoluminal dilatation. Factors independently associated with embedded catheters included catheter dwell time (> 2 years) and history of central venous stenosis. Conclusion Embedded catheters can be successfully managed by endoluminal dilatation with minimal complications and factors associated with embedding include dwell times > 2 years and/or with a history of central venous stenosis. PMID:28346468

[Infectious complications of long term intravenous devices: incidence, risk factors, diagnostic tools].

PubMed

Douard, M C; Ardoin, C; Payri, L; Tarot, J P

1999-03-01

Implantable venous ports and Hickman central venous catheters are widely used in patients with cancer, blood disorders, or HIV infection, both for in-hospital care and at home. Infectious complications are among the common causes for readmission in these patients. The present review discusses the incidence, risk factors, and diagnostic tools for infectious complications associated with long-term venous access devices.

Hydrophilic Catheters

PubMed Central

2006-01-01

catheter package when the catheter is ready to use. Review Strategy The Medical Advisory Secretariat searched for reports of systematic reviews of randomized controlled trials (RCTs), meta-analyses of RCTs, and RCTs. The following databases were searched: Cochrane Library International Agency for Health Technology Assessment (fourth quarter 2005), Cochrane Database of Systematic Reviews (fourth quarter 2005), Cochrane Central Register of Controlled Trials (fourth quarter 2005), MEDLINE (1966 to the third week of November 2005), MEDLINE In-Process and Other Non-indexed Citations (1966 to November 2005), and EMBASE (1980 to week 49 in 2005). Search terms were urinary catheterization, hydrophilic, intermittent, and bladder catheter. The Medical Advisory Secretariat also conducted Internet searches of Medscape (www.medscape.com) for recent reports on trials that were unpublished but presented at international conferences. In addition, the Web site Current Controlled Trials (www.controlled-trials.com) was searched for ongoing trials on urinary catheterization. Summary of Findings Five RCTs were identified that compared hydrophilic catheters to standard catheters. There was substantial variation across the studies in terms of the reason for catheterization, inclusion criteria, and type of catheter used. Two studies used reusable catheters in the control arm, while the other 3 RCTs used single-use catheters in the control arm. All 5 RCTs focused mainly on males requiring intermittent catheterization. Age varied considerably across studies. One study consisted of young males (mean age 12 years), while another included older males (mean age 71 years). The RCTs reported conflicting results regarding the effectiveness of the hydrophilic catheters compared with standard catheters in terms of rates of UTIs. All 5 RCTs had serious limitations. Two of the studies were small, and likely underpowered to detect significant differences between groups. One RCT reported 12-month follow-up data

Long-term outcomes of remote magnetic navigation for ablation of supraventricular tachycardias.

PubMed

Kim, Sung-Hwan; Oh, Yong-Seog; Kim, Dong-Hwi; Choi, Ik Jun; Kim, Tae-Seok; Shin, Woo-Seung; Kim, Ji-Hoon; Jang, Sung-Won; Lee, Man Young; Rho, Tai-Ho

2015-08-01

Little is known about the long-term outcomes of catheter ablation of supraventricular tachycardia (SVT) using remote magnetic navigation system (RMN). One hundred twenty patients underwent catheter ablation of SVTs with RMN (Niobe, Stereotaxis, USA): atrioventricular nodal re-entrant tachycardia (AVNRT; n = 59), atrioventricular re-entrant tachycardia (AVRT; n = 45), and focal atrial tachycardia (AT, n = 16). The outcome of AVRT with right free wall accessory pathway was compared with those of a group of 26 consecutive patients undergoing manual ablation. Mean follow-up period was 2.2 ± 1.4 years. Overall arrhythmia-free survival was 86%; AVRT (77%), AVNRT (96%), and focal AT (71%). After the learning period (initial 50 cases), procedural outcomes had improved for AVRT and AVNRT (91% in overall group, 90% in AVRT group, 100% in AVNRT group, and 68% in focal AT group). The recurrence-free rate was higher for the free wall accessory pathways than those of the other sites (92 vs. 73%, log-rank P = 0.06). Furthermore, when it is confined for the right free wall accessory pathway, RMN showed excellent long-term outcome (7/7, 100 %) compared to the results of manual approach (18/26, 69.2%, log-rank P = 0.07). RMN showed favorable long-term outcomes for the ablation of SVT. In our experience, RMN-guided ablation may be associated with a higher success rate as compared to manual ablation when treating right-sided free wall pathways.

Lights, camera and action in the implementation of central venous catheter dressing.

PubMed

Ferreira, Maria Verônica Ferrareze; de Godoy, Simone; de Góes, Fernanda dos Santos Nogueira; Rossini, Fernanda de Paula; de Andrade, Denise

2015-01-01

To develop and validate an educational digital video on changing the dressing of short-term, non-cuffed, non-tunneled central venous catheters in hospitalized adult patients. This is a descriptive, methodological study based on Paulo Freire's assumptions. The development of the script and video storyboard were based on scientific evidence, on the researchers' experience, and that of nurse experts, as well as on a virtual learning environment. The items related to the script were approved by 97.2% of the nurses and the video was approved by 96.1%. The educational instrument was considered to be appropriate and we believe it will contribute to professional training in the nursing field, the updating of human resources, focusing on the educational process, including distance education. We believe it will consequently improve the quality of care provided to patients with central venous catheters.

Middle-term results of trans-catheter creation of atrial communication in patients receiving mechanical circulatory support.

PubMed

O'Byrne, Michael L; Glatz, Andrew C; Rossano, Joseph W; Schiavo, Kellie L; Dori, Yoav; Rome, Jonathan J; Gillespie, Matthew J

2015-06-01

To describe our center's middle-term outcomes following trans-catheter creation of atrial communication (ASD) in patients on mechanical circulatory support. Trans-catheter creation of an ASD in patients on mechanical circulatory support is an adjuvant therapy to reduce left atrial pressure and associated morbidity. Data on middle term outcomes following this procedure, specifically in regards to the fate of the ASD, are limited. Retrospective observational study of consecutive children and adults undergoing trans-catheter creation of an atrial septal communication between 1/1/2006 and 5/1/2014, reviewing their baseline characteristics, procedural details, and data from follow-up. Over the study period, 37/227 (16%) subjects undergoing veno-arterial extra-corporeal membrane oxygenation (VA-ECMO) underwent trans-catheter creation of an atrial communication. Mortality on VA-ECMO support in this subgroup was 19%, with an additional 24% transitioning to ventricular assist device. Of the 57% who survived to separation from VA-ECMO, 16/21 (76%) had residual atrial communications. 56% of these underwent closure procedures. Following trans-catheter creation of ASD, a residual ASD is present in the majority of assessable survivors and represents a potential volume overload and/or right to left shunt that may need to be addressed. © 2015 Wiley Periodicals, Inc.

Urinary catheters: history, current status, adverse events and research agenda

PubMed Central

Feneley, Roger C. L.; Hopley, Ian B.; Wells, Peter N. T.

2015-01-01

Abstract For more than 3500 years, urinary catheters have been used to drain the bladder when it fails to empty. For people with impaired bladder function and for whom the method is feasible, clean intermittent self-catheterization is the optimal procedure. For those who require an indwelling catheter, whether short- or long-term, the self-retaining Foley catheter is invariably used, as it has been since its introduction nearly 80 years ago, despite the fact that this catheter can cause bacterial colonization, recurrent and chronic infections, bladder stones and septicaemia, damage to the kidneys, the bladder and the urethra, and contribute to the development of antibiotic resistance. In terms of medical, social and economic resources, the burden of urinary retention and incontinence, aggravated by the use of the Foley catheter, is huge. In the UK, the harm resulting from the use of the Foley catheter costs the National Health Service between £1.0–2.5 billion and accounts for ∼2100 deaths per year. Therefore, there is an urgent need for the development of an alternative indwelling catheter system. The research agenda is for the new catheter to be easy and safe to insert, either urethrally or suprapubically, to be retained reliably in the bladder and to be withdrawn easily and safely when necessary, to mimic natural physiology by filling at low pressure and emptying completely without damage to the bladder, and to have control mechanisms appropriate for all users. PMID:26383168

Peritoneal dialysis catheter implantation: avoiding problems and optimizing outcomes.

PubMed

Crabtree, John H

2015-01-01

The success of peritoneal dialysis (PD) as renal replacement therapy is dependent upon the patient having a functional long-term peritoneal access. There are a number of identified best practices that must be adhered to during PD catheter placement to achieve a durable and infection-resistant access. The clinical setting, available resources, and the employed catheter insertion method may not always permit complete adherence to these practices; however, an attempt should be made to comply with them as closely as possible. Although omission of any one of the practices can lead to catheter loss, departures from some are committed more frequently, manifesting as commonly occurring clinical problems, such as drain pain, catheter tip migration, omental entrapment, pericatheter leaks and hernias, and poor exit-site location. Understanding the technical pitfalls in PD catheter placement that lead to these problems, enable the provider to modify practice habits to avoid them and optimize outcomes. © 2014 Wiley Periodicals, Inc.

Urethral versus suprapubic catheter: choosing the best bladder management for male spinal cord injury patients with indwelling catheters.

PubMed

Katsumi, H K; Kalisvaart, J F; Ronningen, L D; Hovey, R M

2010-04-01

Bladder management for male patients with spinal cord injury (SCI) challenges the urologist to work around physical and social restrictions set forth by each patient. The objective of this study was to compare the complications associated with urethral catheter (UC) versus suprapubic tube (SPT) in patients with SCI. A retrospective review of records at Long Beach Veterans Hospital was carried out to identify SCI patients managed with SPT or UC. Chart review identified morbidities including urinary tract infection (UTI), bladder stones, renal calculi, urethral complications, scrotal abscesses, epididymitis, gross hematuria and cancer. Serum creatinine measurements were evaluated to determine whether renal function was maintained. In all, 179 patients were identified. There was no significant difference between the two catheter groups in any areas in which they could be compared. There were catheter-specific complications specific to each group that could not be compared. These included erosion in the UC group and urethral leak, leakage from the SPT and SPT revision in the SPT group. Average serum creatinine for the UC and SPT groups was 0.74 and 0.67 mg per 100 ml, respectively. SCI patients with a chronic catheter have similar complication rates of UTIs, recurrent bladder/renal calculi and cancer. Urethral and scrotal complications may be higher with UC; however, morbidity from SPT-specific procedures may offset benefits from SPT. Serum creatinine was maintained in both groups. Overall, bladder management for patients with chronic indwelling catheters should be selected on the basis of long-term comfort for the patient and a physician mind-set that allows flexibility in managing these challenges.

Perceived Value of a Urinary Catheter Self-Management Program in the Home

PubMed Central

Wilde, Mary; Zhang, Feng; Fairbanks, Eileen; Shah, Shivani; McDonald, Margaret V.; Brasch, Judith

2013-01-01

A long-term indwelling urinary catheter intervention was tested in a randomized trial that is described in this article. The perceived value of the intervention to the catheter users, one of the study’s specific aims, was assessed at the end of their 12-month participation and is reported here. Study participants’ responses, our findings, and implications for home healthcare are discussed. PMID:24081128

Acute cerebellitis successfully managed with temporary cerebrospinal fluid diversion using a long tunnel external ventricular drain: a long-term radiological follow-up of two cases

PubMed Central

Waqas, Muhammad; Hadi, Yousaf Bashir; Sheikh, Sadaf; Shamim, Shahzad M

2016-01-01

Acute cerebellitis (AC) is a rare inflammatory childhood disorder. Although there is no consensus on standard treatment for cerebellitis, its outcome is usually favourable. We report two cases of AC in the paediatric age group, successfully managed with long tunnel external ventricular drain (EVD). The first patient was an 8-year-old boy with a history of fever and headache. Sequential MRI showed diffuse cerebellar swelling with tonsillar herniation and resulting hydrocephalus. The second patient was a 6-month-old boy who presented with high-grade fever associated with chills. CT scan of the head showed triventricular hydrocephalus with obliteration of cerebrospinal fluid spaces and cisterns. Both patients underwent immediate emergency right-sided long tunnel EVD insertion. The EVD was removed on the 9th day in the first patient and the 10th day in the second patient; the patients showed no neurological deficits at a follow-up of 2 years and 1 year, respectively. PMID:27166004

Intermittent catheterization with hydrophilic catheters as a treatment of chronic neurogenic urinary retention.

PubMed

Chartier-Kastler, Emmanuel; Denys, Pierre

2011-01-01

Neurogenic bladder can be effectively managed with intermittent catheterization (IC) to improve or restore continence, but there is no consensus on which type of catheter is preferred. Hydrophilic catheters were developed to reduce urethral friction, thereby minimizing trauma and sticking, and making them more acceptable to the patient, and easier and safer to use. The objective of this article was to review the literature on the benefits of hydrophilic catheters in patients with neurogenic bladder. A large body of experimental and observational evidence, including randomized controlled trials, was identified using PubMed. Compared with plastic catheters that have been manually lubricated with gel, hydrophilic catheters reduce urinary tract infection and microhematuria. Hydrophilic catheters are also associated with high levels of patient satisfaction because they are comfortable to use. There is a wealth of evidence, including randomized controlled trials, to support the benefits of hydrophilic catheters in terms of safety and quality of life, especially in men with spinal cord injury. More data are required for spina bifida, multiple sclerosis, and in women. Further research is warranted, especially large-scale and long-term robust comparisons of different types of catheter, and in well-defined and stratified populations. Copyright © 2010 Wiley-Liss, Inc.

A Review of Arteriovenous Fistulae Creation in Octogenarians.

PubMed

Diandra, Jennifer Clarissa; Lo, Zhiwen Joseph; Ang, Wei-Wen; Feng, Jue Fei; Narayanan, Sriram; Tan, Glenn Wei Leong; Chandrasekar, Sadhana

2018-01-01

To analyze the outcomes of arteriovenous fistulae (AVFs) creation in octogenarians. A retrospective study of 47 AVFs created in patients aged 80 years and above from 2008 to 2014. Patient and AVF characteristics and outcomes were evaluated. Predictors of patency were analyzed with multivariate analysis and Kaplan-Meier patency, and survival analysis was performed. Forty-seven of 1,259 AVFs created were for octogenarians (4%). Mean age was 83 years old (range: 80-91 years), with 27 male (57%) and 35 with tunneled dialysis catheters in situ (75%). There were a total of 15 (32%) radiocephalic AVFs, 30 (64%) brachial-cephalic AVFs, and 2 (4%) brachial-basilic transposition AVFs. At 12 months, assisted primary patency rate was 28% (13 patients) while primary failure rate was 72% (34 patients). Subset analysis showed brachial-cephalic AVFs to have the highest assisted primary patency rate at 33%. Within 24 months, tunneled dialysis catheter-related sepsis rate was 31% (11 patients). Multivariate analysis did not reveal any factor to be statistically significant in predicting AVF patency. Kaplan-Meier survival curve showed a 50% survival rate at 63 months after AVF creation. In view of high AVF primary failure rate and relatively low tunneled dialysis catheter bacteremia rate, long-term tunneled dialysis catheters as the main form of hemodialysis renal access may be a viable option. However, with 50% of end-stage renal failure patients surviving up to 63 months after AVF creation, the risks and benefits of long-term tunneled dialysis catheters must be balanced against those of AVF creation. Copyright © 2017 Elsevier Inc. All rights reserved.

Lymphatic Leak Complicating Central Venous Catheter Insertion

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

Barnacle, Alex M., E-mail: alexbarnacle@yahoo.co.uk; Kleidon, Tricia M.

2005-12-15

Many of the risks associated with central venous access are well recognized. We report a case of inadvertent lymphatic disruption during the insertion of a tunneled central venous catheter in a patient with raised left and right atrial pressures and severe pulmonary hypertension, which led to significant hemodynamic instability. To our knowledge, this rare complication is previously unreported.

Relationship between Race and the Effect of Fluids on Long-term Mortality after Acute Respiratory Distress Syndrome. Secondary Analysis of the National Heart, Lung, and Blood Institute Fluid and Catheter Treatment Trial.

PubMed

Jolley, Sarah E; Hough, Catherine L; Clermont, Gilles; Hayden, Douglas; Hou, Suqin; Schoenfeld, David; Smith, Nicholas L; Thompson, Boyd Taylor; Bernard, Gordon R; Angus, Derek C

2017-09-01

Short-term follow-up in the Fluid and Catheter Treatment Trial (FACTT) suggested differential mortality by race with conservative fluid management, but no significant interaction. In a post hoc analysis of FACTT including 1-year follow-up, we sought to estimate long-term mortality by race and test for an interaction between fluids and race. We performed a post hoc analysis of FACTT and the Economic Analysis of Pulmonary Artery Catheters (EAPAC) study (which included 655 of the 1,000 FACTT patients with near-complete 1-year follow up). We fit a multistate Markov model to estimate 1-year mortality for all non-Hispanic black and white randomized FACTT subjects. The model estimated the distribution of time from randomization to hospital discharge or hospital death (available on all patients) and estimated the distribution of time from hospital discharge to death using data on patients after hospital discharge for patients in EAPAC. The 1-year mortality was found by combining these estimates. Non-Hispanic black (n = 217, 25%) or white identified subjects (n = 641, 75%) were included. There was a significant interaction between race and fluid treatment (P = 0.012). One-year mortality was lower for black subjects assigned to conservative fluids (38 vs. 54%; mean mortality difference, 16%; 95% confidence interval, 2-30%; P = 0.027 between conservative and liberal). Conversely, 1-year mortality for white subjects was 35% versus 30% for conservative versus liberal arms (mean mortality difference, -4.8%; 95% confidence interval, -13% to 3%; P = 0.23). In our cohort, conservative fluid management may have improved 1-year mortality for non-Hispanic black patients with ARDS. However, we found no long-term benefit of conservative fluid management in white subjects.

Is catheter-directed foam sclerotherapy more effective than the usual foam sclerotherapy for treatment of the great saphenous vein?

PubMed

Camillo, Orsini

2018-01-01

Objective This retrospective study presents the long-term results of catheter-directed foam sclerotherapy of the great saphenous vein. Method From January 2003 to June 2017, 277 patients with varices and great saphenous vein incompetence were treated with echo-guided foam sclerotherapy. Forty-six patients were treated with long-catheters guided by foam sclerotherapy. Foaming was carried out with sodium-tetra-decyl-sulphate. Results Results were examined in the two groups: A (long-catheters) and B (other procedures). The median overall follow-up was 52.1 months. In the A-group, the complete occlusion rate was 34/46 pts (73.9%) and partial occlusion was 10/46 (21.7%). In the B-group, respectively, 130/231 (56.2%) and 90/231 (38.9%). Comparisons between groups were statistically significant (p = 0.023; p = 0.021). Failures involved, respectively, 2/46 (4.3%) and 11/231 (4.7%) with no statistical significance. The complication rates were similar in the two groups. Conclusions In this long-term experience (median follow-up exceeding four years), foam-guided sclerotherapy of the great saphenous vein with a long-catheter turned out to be more effective than the usual foam-guided sclerotherapy.

Long-segment plication technique for arteriovenous fistulae threatened by diffuse aneurysmal degeneration: short-term results.

PubMed

Powell, Alexis; Wooster, Mathew; Carroll, Megan; Cardentey-Oliva, Damian; Cavanagh-Voss, Sean; Armstrong, Paul; Shames, Murray; Illig, Karl; Gabbard, Wesley

2015-08-01

A substantial number of patients with autologous arteriovenous fistulas (AVFs) develop diffuse aneurysmal degeneration, which frequently interferes with successful access. These AVFs are often deemed unsalvageable. We hypothesize that long-segment plication in these patients can be performed safely with acceptable short-term AVF salvage rates. We reviewed a prospectively maintained database to identify all patients with extensive AVF aneurysmal disease operated on for this problem. Thirty-five patients, 25 (71%) male and 10 (29%) female were operated on between July 2012 and January 2014. AVFs included 23 (66%) brachiocephalic, 5 (14%) radiocephalic, and 7 brachiobasilic (20%) fistulae (one first stage only but in use). The cohort had one or a combination of local pain, arm edema, cannulation issue, recurrent thrombosis, dysfunctional during dialysis, or extreme tortuousity. Time range for AVF creation to consultation ranged from 3 months to 11 years. All underwent long-segment plication over a 20-Fr Bougie with or without segmental vein resection; 3 underwent concomitant first rib resection for costoclavicular stenosis; 21 patients had tunneled catheter placement for use while healing, whereas 13 were allowed segmental use of their AVF during the perioperative period (1 patient was not yet on dialysis). Early in our experience, AVFs were left under the wound, whereas all but one repaired since early 2013 were left under a lateral flap. All patients were followed by clinical examination and duplex. In the 30-day postoperative period, 2 AVFs (5.7%) became infected requiring excision, 2 occluded (5.7%), 1 day 1 and the other at 24 days out, 1 patient developed steal and required DRIL 1 week postoperatively, and 1 patient died, unrelated to his surgery. Postoperative functional primary patency was 88% (30 of 34). Of the patients needing temporary access catheter, mean time to first fistula use was 44 days. No wound or bleeding complications have occurred in repaired

Lights, camera and action in the implementation of central venous catheter dressing1

PubMed Central

Ferreira, Maria Verônica Ferrareze; de Godoy, Simone; de Góes, Fernanda dos Santos Nogueira; Rossini, Fernanda de Paula; de Andrade, Denise

2015-01-01

Objective: to develop and validate an educational digital video on changing the dressing of short-term, non-cuffed, non-tunneled central venous catheters in hospitalized adult patients. Method: this is a descriptive, methodological study based on Paulo Freire's assumptions. The development of the script and video storyboard were based on scientific evidence, on the researchers' experience, and that of nurse experts, as well as on a virtual learning environment. Results: the items related to the script were approved by 97.2% of the nurses and the video was approved by 96.1%. Conclusion: the educational instrument was considered to be appropriate and we believe it will contribute to professional training in the nursing field, the updating of human resources, focusing on the educational process, including distance education. We believe it will consequently improve the quality of care provided to patients with central venous catheters. PMID:26626011

[Experitoneal bladder perforation due to in-dwelling urethral catheter successfully treated by urethral drainage: a case report].

PubMed

Okuda, Hidenobu; Tei, Norihide; Shimizu, Kiyonori; Imazu, Tetsuo; Yoshimura, Kazuhiro; Kiyohara, Hisakazu

2008-07-01

Perforation of the bladder related to long-term indwelling urethral catheter is a rare and serious complication. A 85-year-old man with an indwelling urethral catheter presented severe hematuria, abdominal pain with rebound tenderness and muscular tension over the suprapubic area after the exchange of the urethral catheter. Computed tomography and cystogram revealed experitoneal bladder perforation due to indwelling catheter. Three weeks after the indwelling urethral catheter had been placed, the perforation was closed. In most cases, laparotomy and suprapubic cystostomy are performed. We describe the case of experitoneal bladder perforation successfully treated by urethral drainage.

Efficacy of Antiarrhythmic Drugs Short-Term Use After Catheter Ablation for Atrial Fibrillation (EAST-AF) trial.

PubMed

Kaitani, Kazuaki; Inoue, Koichi; Kobori, Atsushi; Nakazawa, Yuko; Ozawa, Tomoya; Kurotobi, Toshiya; Morishima, Itsuro; Miura, Fumiharu; Watanabe, Tetsuya; Masuda, Masaharu; Naito, Masaki; Fujimoto, Hajime; Nishida, Taku; Furukawa, Yoshio; Shirayama, Takeshi; Tanaka, Mariko; Okajima, Katsunori; Yao, Takenori; Egami, Yasuyuki; Satomi, Kazuhiro; Noda, Takashi; Miyamoto, Koji; Haruna, Tetsuya; Kawaji, Tetsuma; Yoshizawa, Takashi; Toyota, Toshiaki; Yahata, Mitsuhiko; Nakai, Kentaro; Sugiyama, Hiroaki; Higashi, Yukei; Ito, Makoto; Horie, Minoru; Kusano, Kengo F; Shimizu, Wataru; Kamakura, Shiro; Morimoto, Takeshi; Kimura, Takeshi; Shizuta, Satoshi

2016-02-14

Substantial portion of early arrhythmia recurrence after catheter ablation for atrial fibrillation (AF) is considered to be due to irritability in left atrium (LA) from the ablation procedure. We sought to evaluate whether 90-day use of antiarrhythmic drug (AAD) following AF ablation could reduce the incidence of early arrhythmia recurrence and thereby promote reverse remodelling of LA, leading to improved long-term clinical outcomes. A total of 2038 patients who had undergone radiofrequency catheter ablation for paroxysmal, persistent, or long-lasting AF were randomly assigned to either 90-day use of Vaughan Williams class I or III AAD (1016 patients) or control (1022 patients) group. The primary endpoint was recurrent atrial tachyarrhythmias lasting for >30 s or those requiring repeat ablation, hospital admission, or usage of class I or III AAD at 1 year, following the treatment period of 90 days post ablation. Patients assigned to AAD were associated with significantly higher event-free rate from recurrent atrial tachyarrhythmias when compared with the control group during the treatment period of 90 days [59.0 and 52.1%, respectively; adjusted hazard ratio (HR) 0.84; 95% confidence interval (CI) 0.73-0.96; P = 0.01]. However, there was no significant difference in the 1-year event-free rates from the primary endpoint between the groups (69.5 and 67.8%, respectively; adjusted HR 0.93; 95% CI 0.79-1.09; P = 0.38). Short-term use of AAD for 90 days following AF ablation reduced the incidence of recurrent atrial tachyarrhythmias during the treatment period, but it did not lead to improved clinical outcomes at the later phase. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

Going with the flow or swimming against the tide: should children with central venous catheters swim?

PubMed

Miller, Jessica; Dalton, Meghan K; Duggan, Christopher; Lam, Shirley; Iglesias, Julie; Jaksic, Tom; Gura, Kathleen M

2014-02-01

Children who require long-term parenteral nutrition (PN) have central venous catheters (CVCs) in place to allow the safe and effective infusion of life-sustaining fluids and nutrition. Many consider recreational swimming to be a common part of childhood, but for some, the risk may outweigh the benefit. Children with CVCs may be at increased risk of exit site, tunnel, and catheter-related bloodstream infections (CRBSIs) if these catheters are immersed in water. The purpose of this review is to evaluate the current literature regarding the risk of infection for patients with CVCs who swim and determine if there is consensus among home PN (HPN) programs on this controversial issue. A total 45 articles were reviewed and 16 pediatric HPN programs were surveyed regarding swimming and CVCs. Due to the limited data available, a firm recommendation cannot be made. Recreational water associated outbreaks are well documented in the general public, as is the presence of human pathogens even in chlorinated swimming pools. As a medical team, practitioners can provide information and education regarding the potential risk, but ultimately the decision lies with the parents. If the parents decide swimming is worth the risk, they are encouraged to use products designed for this use and to change their child's dressing immediately after swimming. Due to our experience with a fatal event immediately after swimming, we continue to strongly discourage patients with CVCs from swimming. Further large and well-designed studies regarding the risk of swimming with a CVC are needed to make a strong, evidence-based recommendation.

[Chronic outcome of patients with paroxysmal atrial fibrillation post catheter ablation].

PubMed

Lin, Yu-bi; Xia, Yun-long; Gao, Lian-jun; Chu, Zhen-liang; Cong, Pei-xin; Chang, Dong; Yin, Xiao-meng; Zhang, Shu-long; Yang, Dong-Hui; Yang, Yan-Zong

2009-12-01

High short-term successful rate was reported for catheter ablation in patients with paroxysmal atrial fibrillation (AF), we analyzed the long-term outcome (success rate, anticoagulation therapy and embolism event, anti-arrhythmic therapy and death post procedure) of catheter ablation for paroxysmal AF in this study. From January 2000 to December 2004, 106 consecutive patients with drug-refractory paroxysmal AF underwent catheter ablation and were followed-up for (60.7 + or - 11.8) months. Segmental pulmonary vein isolation (SPVI) was routinely performed by radiofrequency energy under the guidance of circular mapping catheter. The patients were followed up with 24 h-holter, ECG, telephone or letter. Data on recurrence of AF, the anticoagulation medication and the incidence of embolism, anti-arrhythmic therapy were obtained. There were 9 patients lost to follow up. In the remaining 97 patients [65 males, (54.8 + or - 11.2) years old], 3 cases died from cancer, sinus rhythm was maintained in 68 patients (Group S, 72.3%) and AF recurrence evidenced in 26 patients (Group R, 27.7%). In Group S, 56 patients (82.4%) discontinued anticoagulation medication, and 12 patients continued to take aspirin. There was no embolism event in Group S during follow-up. In Group R, 1 patient continued to take warfarin; 11 patients continued to take aspirin and 2 patients suffered from cerebral embolism. Anticoagulation medication was discontinued in 14 patients (53.8%) and 1 patient suffered form cerebral embolism. The incidence of embolism event in Group R is significantly higher than in Group S (P < 0.01). More patients discontinued anti-arrhythmic medication in Group S than in Group R (80.9% vs. 56.0%, P < 0.05). Catheter ablation is associated with satisfactory long-term success rate, reduced anti-arrhythmia medication, improved quality of life in patients with paroxysmal AF.

Value of an old school approach: safety and long-term success of radiofrequency current catheter ablation of atrioventricular nodal reentrant tachycardia in children and young adolescents.

PubMed

Siebels, Henrike; Sohns, Christian; Nürnberg, Jan-Hendrik; Siebels, Jürgen; Langes, Klaus; Hebe, Joachim

2018-05-15

Radiofrequency current energy (RFC) ablation is still considered as the gold standard for atrioventricular nodal reentrant tachycardia (AVNRT). Success-rates for AVNRT ablation vary irrespective of the ablation technology and strategy. This study aimed to access safety, efficacy, and long-term outcome of RFC catheter ablation for the treatment of AVNRT in children and adolescents aged < 19 years with special focus on modulation versus ablation of the AV nodal slow pathway (SP). A total number of 1143 patients (pts) < 19 years were referred for invasive electrophysiological testing due to paroxysmal supraventricular tachycardia (SVT). Diagnosis of AVNRT was confirmed in 412 pts, and RFC-guided ablation was attempted in 386 pts (age 13.0 ± 3.5 years). No permanent complications were observed. RFC application resulted in SP-ablation in 171/386 (44.3%) and in SP modulation in 208/386 (53.9%) children, whereas attempts for RFC treatment failed in 7 pts. Follow-up was completed for 396/412 patients (96.1%). Within a mean follow-up period of 54.9 ± 39.7 months, in 51/379 pts (13.5%) AVNRT recurrence was observed. The median time until tachycardia recurrence was 19.5 months. No difference for AVNRT recurrence was found comparing SP ablation versus SP modulation (p > 0.05), whereas the recurrence rate was significantly higher in patients with non-inducible SVT and therefore empiric SP treatment as compared to patients with inducible AVNRT (p = 0.01). RFC-guided ablation for AVNRT in children and adolescents is safe and leads to an acceptable long-term freedom from recurrences. SP modulation and SP ablation resulted in comparable acute and long-term success rates. Late AVNRT recurrences can occur even after years of freedom from tachycardia-related symptoms.

Minimizing Hemodialysis Catheter Dysfunction: An Ounce of Prevention

PubMed Central

Lee, Timmy; Lok, Charmaine; Vazquez, Miguel; Moist, Louise; Maya, Ivan; Mokrzycki, Michele

2012-01-01

The maintenance of tunneled catheter (TC) patency is critical for the provision of adequate hemodialysis in patients who are TC-dependent. TC dysfunction results in the need for costly and inconvenient interventions, and reduced quality of life. Since the introduction of TCs in the late 1980s, heparin catheter lock has been the standard prophylactic regimen for the prevention of TC dysfunction. More recently, alternative catheter locking agents have emerged, and in some cases have shown to be superior to heparin lock with respect to improving TC patency and reducing TC-associated infections. These include citrate, tissue plasminogen activator, and a novel agent containing sodium citrate, methylene blue, methylparaben, and propylparaben. In addition, prophylaxis using oral anticoagulants/antiplatelet agents, including warfarin, aspirin, ticlodipine, as well as the use of modified heparin-coated catheters have also been studied for the prevention of TC dysfunction with variable results. The use of oral anticoagulants and/or antiplatelet agents as primary or secondary prevention of TC dysfunction must be weighed against their potential adverse effects, and should be individualized for each patient. PMID:22518310

Determining the noninfectious complications of indwelling urethral catheters: a systematic review and meta-analysis.

PubMed

Hollingsworth, John M; Rogers, Mary A M; Krein, Sarah L; Hickner, Andrew; Kuhn, Latoya; Cheng, Alex; Chang, Robert; Saint, Sanjay

2013-09-17

Although the epidemiology of catheter-associated urinary tract infection is well-described, little is known about noninfectious complications resulting from urethral catheter use. To determine the frequency of noninfectious complications after catheterization. MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, CINAHL, Conference Papers Index, BIOSIS Previews, Scopus, and ClinicalTrials.gov were searched for human studies without any language limits and through 30 July 2012. Clinical trials and observational studies assessing noninfectious complications of indwelling urethral catheters in adults. Relevant studies were sorted into 3 categories: short-term catheterization in patients without spinal cord injury (SCI), long-term catheterization in patients without SCI, and catheterization in patients with SCI. The proportion of patients who had bladder cancer, bladder stones, blockage, false passage, gross hematuria, accidental removal, urine leakage, or urethral stricture was then pooled using random-effects models. Thirty-seven studies (2868 patients) were pooled. Minor complications were common. For example, the pooled frequency of urine leakage ranged from 10.6% (95% CI, 2.4% to 17.7%) in short-term catheterization cohorts to 52.1% (CI, 28.6% to 69.5%) among outpatients with long-term indwelling catheters. Serious complications were also noted, including urethral strictures, which occurred in 3.4% (CI, 1.0% to 7.0%) of patients with short-term catheterization. For patients with SCI, 13.5% (CI, 3.4% to 21.9%) had gross hematuria and 1.0% (CI, 0.0% to 5.0%) developed bladder cancer. Although heterogeneity existed across studies for several outcomes, most could be accounted for by differences between studies with respect to quality and sex composition. Evidence published after 30 July 2012 is not included. Many noninfectious catheter-associated complications are at least as common as clinically significant urinary tract infections. Agency for Healthcare

A qualitative descriptive study of self-management issues in people with long-term intermittent urinary catheters.

PubMed

Wilde, Mary H; Brasch, Judith; Zhang, Yi

2011-06-01

The study was to identify and describe issues of intermittent urinary catheter users for future self-management research and/or training programmes. Limited studies were found of how people using clean intermittent catheterization manage their daily routines or troubleshoot problems. Self-management research related to intermittent catheterization could lead to improved compliance with the method and better quality of life. This qualitative descriptive study involved in-depth tape-recorded telephone interviews in 2008-2009 with 34 people in the United States of America using permanent intermittent catheterization, mostly individuals with spinal cord injury or multiple sclerosis. Recruitment was through Internet sites where individuals could link to the study website and then contact the researchers. The sample included 13 men and 21 women aged 21-72 years (mean 42 years). Content analysis for qualitative data involved iterative comparisons of transcripts, summaries and memos. Coding, key quotes and tables were developed to determine themes. Six major themes were identified: Knowing the Body, Practising Intermittent Catheterization, Limited Options in Catheters and Equipment, Inaccessible Bathrooms, Hassles, and Adjustment in Making Intermittent Catheterization a Part of Life. While some persons had choices in catheters, many did not because of insurance constraints. Some individuals developed knowledge of how to balance the procedure with fluid intake and activities. The lack of acceptable bathrooms can interfere with being able to go to work, travel or be with friends and family. All using intermittent catheterization should have adequate insurance coverage when this is needed. Research into training programmes could incorporate knowledge of experienced users. © 2011 Blackwell Publishing Ltd.

Implementing clinical guidelines to prevent catheter-associated urinary tract infections and improve catheter care in nursing homes: Systematic review.

PubMed

Gould, Dinah; Gaze, Sarah; Drey, Nicholas; Cooper, Tracey

2017-05-01

Catheter-associated urinary tract infection is the most common health care-associated infection, is considered avoidable, and has cost implications for health services. Prevalence is high in nursing homes, but little research has been undertaken to establish whether implementing clinical guidelines can reduce infection rates in long-term care or improve quality of urinary catheter care. Systematic search and critical appraisal of the literature. Three studies evaluated the impact of implementing a complete clinical guideline. Five additional studies evaluated the impact of implementing individual elements of a clinical guideline. Prevention of catheter-associated urinary tract infection in nursing homes has received little clinical or research attention. Studies concerned with whole guideline implementation emerged as methodologically poor using recognized criteria for critically appraising epidemiologic studies concerned with infection prevention. Research evaluating the impact of single elements of clinical guidelines is more robust, and their findings could be implemented to prevent urinary infections in nursing homes. Copyright © 2017. Published by Elsevier Inc.

Sodium citrate 4% versus heparin as a lock solution in hemodialysis patients with central venous catheters.

PubMed

Yon, Calantha K; Low, Chai L

2013-01-15

The effects of heparin versus sodium citrate 4% as a lock solution on catheter-related infections (CRIs), catheter patency, and hospitalizations in long-term hemodialysis patients with central venous catheters (CVCs) were compared. Data for patients receiving heparin lock solutions were collected from July 2008 to July 2009. Data on patients receiving sodium citrate 4% lock solution were collected from September 2009 through December 2010. Patients who were receiving the heparin lock solution who continued to have a CVC in September 2009 were transitioned from heparin to sodium citrate catheter 4% lock solution. New patients with CVCs placed after September 2009 received sodium citrate 4% without a period of using heparin lock solution. Pertinent information on patient medical history, bleeding or clotting events, infections, and hospitalization was collected. Data were collected retrospectively for the heparin group and prospectively for the sodium citrate group. Data were collected from 360 patient-months among 60 patients during the heparin treatment period and from 451 patient-months among 58 patients during the sodium citrate period. Thirty-three patients were common to both study groups. There were significantly more CRIs and CRIs per 1000 catheter-days in the heparin than the sodium citrate treatment group. Secondary outcomes of hospitalizations and catheter thrombosis were comparable. CRIs and thrombosis led to significantly more catheter exchanges or removals in the heparin group than the sodium citrate group. In patients with long-term hemodialysis catheters, a lock solution of sodium citrate 4% was associated with fewer CRIs and similar effectiveness when compared with heparin 5000 units/mL.

Management of complications related to central venous catheters in cancer patients: an update.

PubMed

Linnemann, Birgit

2014-04-01

Central venous catheters (CVCs) are important for the treatment of patients with cancer, especially in the perioperative and palliative care settings. These devices not only allow for the administration of chemotherapy, parenteral nutrition, and other intravenous therapies, but they may also improve the patients' quality of life by reducing the need for repeated peripheral venipunctures. Thrombotic and infectious complications are common, especially in the long-term use of CVCs. There are different types of thrombotic complications associated with CVCs, that is, a thrombotic occlusion of the catheter, a mural thrombus at the catheter tip and classical deep vein thrombosis, which occurs most frequently in the upper extremity where the majority of long-term catheters are inserted. Infections are common complications associated with CVCs. Patients with cancer who receive intensive chemotherapy and those patients who undergo hematopoietic stem cell transplantation have a markedly increased risk for insertion site and bloodstream infections. In this review, the epidemiology and risk factors that predispose patients to CVC-related thrombosis and infection are discussed. The diagnostic and therapeutic options according to the published data and the current guidelines are summarized and data for establishing primary and secondary preventative strategies are provided. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Endovascular recanalization of a port catheter-associated superior vena cava syndrome.

PubMed

Tonak, Julia; Fetscher, Sebastian; Barkhausen, Jörg; Goltz, Jan Peter

2015-01-01

Superior vena cava (SVC) syndrome owing to benign etiology is rare and endovascular techniques have been advocated as the treatment of choice. We report a case of endovascular revascularization of a port catheter-associated complete occlusion of the SVC with reversed flow in the azygos vein. In this setting using a sheath in combination with its dilatator to pass the occlusion of the SVC after neither a diagnostic catheter nor a PTA balloon would pass the lesion may be a valid option. A dual venous approach was established using the right common femoral vein and an indwelling port catheter in the right cephalic vein to dilate and stent the lesion. Finally, a port may be implanted after the revascularization had been successful. Passage through the port catheter-associated occlusion of the SVC was only possible by use of the sheath in combination with its dilatator. A dual venous access by the femoral approach and the indwelling central catheter is helpful in treating a SVC occlusion. Long-term central venous catheters may cause SVC syndrome, especially with a catheter tip located too far cranially. An endovascular revascularization of a complete occlusion of the SVC represents the therapy of choice.

Long-Term Outcomes of Catheter Ablation of Electrical Storm in Nonischemic Dilated Cardiomyopathy Compared With Ischemic Cardiomyopathy.

PubMed

Muser, Daniele; Liang, Jackson J; Pathak, Rajeev K; Magnani, Silvia; Castro, Simon A; Hayashi, Tatsuya; Garcia, Fermin C; Supple, Gregory E; Riley, Michael P; Lin, David; Dixit, Sanjay; Zado, Erica S; Frankel, David S; Callans, David J; Marchlinski, Francis E; Santangeli, Pasquale

2017-07-01

The goal of this study was to determine the long-term outcomes of catheter ablation (CA) of electrical storm in patients with nonischemic dilated cardiomyopathy (NIDCM) compared with patients with ischemic cardiomyopathy (ICM). CA of ventricular tachycardia (VT) electrical storm has been shown to improve VT-free survival in patients with ICM. Data on the outcomes of CA of electrical storm in patients with NIDCM are insufficient. The study included 267 consecutive patients with NIDCM (n = 71; ejection fraction 32 ± 14%) and ICM (n = 196; ejection fraction 28 ± 12%). Endo-epicardial CA was performed in 59 (22%) patients. CA was guided by activation and entrainment mapping for tolerated VT and pacemapping/targeting of abnormal substrate for unmappable VT. After a median follow-up of 45 (25th to 75th percentile: 9 to 71) months and 1 (25th to 75th percentile: 1 to 8) procedures, 76 (29%) patients died, 25 (9%) underwent heart transplantation, 87 (33%) experienced VT recurrence, and 13 (5%) had recurrence of electrical storm. Overall VT-free survival was 54% at 60 months (48% in NIDCM and 54% in ICM; p = 0.128). Patients with VT recurrence experienced a median of 2 (1 to 10) VT episodes in the 5 (1 to 14) months after the procedure. Death/transplantation-free survival was 62% at 60 months (53% in NIDCM and 64% in ICM; p = 0.067). Persistent inducibility of any VT with cycle length ≥250 ms at programmed stimulation at the end of the procedure was the only independent predictor of VT recurrence. Low ejection fraction, New York Heart Association functional class, and VT recurrence over follow-up independently predicted death/transplantation. CA of electrical storm was similarly effective in patients with NIDCM compared with patients with ICM, with elimination of electrical storm in 95% of cases and achievement of complete VT control at long-term follow-up in most patients. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc

Long-Term Natural History of Adult Wolff-Parkinson-White Syndrome Patients Treated With and Without Catheter Ablation.

PubMed

Bunch, T Jared; May, Heidi T; Bair, Tami L; Anderson, Jeffrey L; Crandall, Brian G; Cutler, Michael J; Jacobs, Victoria; Mallender, Charles; Muhlestein, Joseph B; Osborn, Jeffrey S; Weiss, J Peter; Day, John D

2015-12-01

There are a paucity of data about the long-term natural history of adult Wolff-Parkinson-White syndrome (WPW) patients in regard to risk of mortality and atrial fibrillation. We sought to describe the long-term outcomes of WPW patients and ascertain the impact of ablation on the natural history. Three groups of patients were studied: 2 WPW populations (ablation: 872, no ablation: 1461) and a 1:5 control population (n=11 175). Long-term mortality and atrial fibrillation rates were determined. The average follow-up for the WPW group was 7.9±5.9 (median: 6.9) years and was similar between the ablation and nonablation groups. Death rates were similar between the WPW group versus the control group (hazard ratio, 0.96; 95% confidence interval, 0.83-1.11; P=0.56). Nonablated WPW patients had a higher long-term death risk compared with ablated WPW patients (hazard ratio, 2.10; 95% confidence interval: 1.50-20.93; P<0.0001). Incident atrial fibrillation risk was higher in the WPW group compared with the control population (hazard ratio, 1.55; 95% confidence interval, 1.29-1.87; P<0.0001). Nonablated WPW patients had lower risk than ablated patients (hazard ratio, 0.39; 95% confidence interval, 0.28-0.53; P<0.0001). Long-term mortality rates in WPW patients are low and similar to an age-matched and gender-matched control population. WPW patients that underwent the multifactorial process of ablation had a lower mortality compared to nonablated WPW patients. Atrial fibrillation rates are high long-term, and ablation does not reduce this risk. © 2015 American Heart Association, Inc.

Washout policies in long-term indwelling urinary catheterisation in adults.

PubMed

Shepherd, Ashley J; Mackay, William G; Hagen, Suzanne

2017-03-06

People requiring long-term bladder draining with an indwelling catheter can experience catheter blockage. Regimens involving different solutions can be used to wash out catheters with the aim of preventing blockage. This is an update of a review published in 2010. To determine if certain washout regimens are better than others in terms of effectiveness, acceptability, complications, quality of life and critically appraise and summarise economic evidence for the management of long-term indwelling urinary catheterisation in adults. We searched the Cochrane Incontinence Group Specialised Trials Register, which contains trials identified from the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, MEDLINE In-Process, MEDLINE Epub Ahead of Print, CINAHL, ClinicalTrials.gov, WHO ICTRP and handsearching of journals and conference proceedings to 23 May 2016. We also examined all reference lists of identified trials and contacted manufacturers and researchers in the field. All randomised and quasi-randomised trials comparing catheter washout policies (e.g. washout versus no washout, different washout solutions, frequency, duration, volume, concentration, method of administration) in adults (aged 16 years and above) in any setting (i.e. hospital, nursing/residential home, community) with an indwelling urethral or suprapubic catheter for more than 28 days. Two review authors independently extracted data. Disagreements were resolved by discussion. Data were assessed and analysed as described in the Cochrane Handbook. If data in trials were not fully reported, clarification was sought from the study authors. For categorical outcomes, the numbers reporting an outcome were related to the numbers at risk in each group to derive a risk ratio (RR). For continuous outcomes, means and standard deviations were used to derive mean differences (MD). We included seven trials involving a total of 349 participants, 217 of whom completed the studies. Three were cross-over and

WKB approximation and tunneling in theories with noncanonical kinetic terms

NASA Astrophysics Data System (ADS)

González, Mariana Carrillo; Masoumi, Ali; Solomon, Adam R.; Trodden, Mark

2017-09-01

Tunneling is a fascinating aspect of quantum mechanics that renders the local minima of a potential meta-stable, with important consequences for particle physics, for the early hot stage of the universe, and more speculatively, for the behavior of the putative multiverse. While this phenomenon has been studied extensively for systems which have canonical kinetic terms, many theories of fundamental physics contain fields with noncanonical kinetic structures. It is therefore desirable to have a detailed framework for calculating tunneling rates and initial states after tunneling for these theories. In this work we present such a rigorous formulation and illustrate its use by applying it to a number of examples.

The development of a pseudo-chamber after balloon pulmonary angioplasty: long-term complications of balloon pulmonary angioplasty.

PubMed

Sugiyama, Hisashi; Kise, Hiroaki; Toda, Takako; Hoshiai, Minako

2016-11-01

We experienced a rare complication where extravasation developed a pseudo-chamber long after the balloon pulmonary angioplasty for supravalvular pulmonary stenosis. A 3-month-old girl was diagnosed with an anomalous origin of the left coronary artery from the pulmonary artery. She underwent the Takeuchi procedure at 10 months of age. During the follow-up, the supravalvular pulmonary stenosis deteriorated, and was treated by balloon pulmonary angioplasty with the double balloon technique catheter at 6 years of age. Angiography at the main pulmonary artery showed a small amount of extravasation contrast medium after the procedure. Follow-up echocardiography showed a diminished extravasation hemorrhage. Twelve years later, right ventricular enlargement due to pulmonary regurgitation had been observed on echocardiography. In addition, abnormal echo free space was detected at the left posterior of the left atrium. Enhanced computed tomography clearly demonstrated there was an orifice and extent of the pseudo-chamber. Surgical findings revealed a large tear just distal to the coronary tunnel. We speculated that extravasation blood was limited in the perivascular area early after the procedure but eventually reached the non-adhesive oblique pericardial sinus with age. Consequently, pulmonary to oblique pericardial sinus communication was established and looked like a pseudo-chamber long after the procedure. In conclusion, even if extravasation seems to be limited immediately after the balloon pulmonary angioplasty, it could expand for non-adhesive space and could develop a huge blood space like chamber. Long-term careful observation should be necessary for extravasation of pulmonary artery even with surgical adhesion.

[Intrathoracic migration of a ventriculoperitoneal shunt catheter: a case report].

PubMed

Sánchez-Medina, Yanire; Domínguez-Báez, Jaime; Lazo-Fernández, Eglis; Pérez Del Rosario, Pedro Antonio; Zanabria-Ortiz, Robert

2015-01-01

The intrathoracic complications from ventriculoperitoneal shunt placement are very rare. However, they are potentially serious if not treated. We report the case of thoracic migration of a peritoneal catheter after ventriculoperitoneal shunt and we also review the literature references with discussion of the different mechanisms of shunt-tip migration described. No case of previous sternotomy as in our patient has been found published. All reports recommend early catheter repositioning into the peritoneal cavity after diagnosing the migration described, to prevent worse complications. Moreover, it is important to keep in mind that intrathoracic migration can happen and it is necessary to palpate the catheter continuously during passage through subcutaneous tunnelling to prevent it. Copyright © 2014 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.

Modified laparoscopic placement of peritoneal dialysis catheter with intra-abdominal fixation.

PubMed

Shen, Quanquan; Jiang, Xinxin; Shen, Xiaogang; Yu, Fangyan; Tu, Qiudi; Chen, Wangfang; Ye, Qing; Behera, Tapas Ranjan; He, Qiang

2017-08-01

Peritoneal dialysis (PD) is a commonly accepted method of treating end-stage renal disease (ESRD). Various laparoscopic techniques for the placement of PD catheter have been described. In this study, we developed a novel modified laparoscopic technique for PD catheter placement and evaluated the early results. A straight Tenckhoff PD catheter was placed employing the modified technique in 39 consecutive patients with ESRD from May 2013 to April 2016. The technique is laparoscopically guided intra-abdominal fixation of the PD catheter tip at one point by using suture passer hernia forceps. Individual information including sex, age, primary disease etiology, complications, surgical duration, morbidity, mortality and catheter survival was collected and analyzed. The modified laparoscopic procedure was effectively performed in all patients with a mean operative time of 45 ± 7 min. No conversions from laparoscopy to open surgery of catheter placement occurred. There was one case showing early pericatheter leakage. There were no serious complications, such as bleeding, abdominal wall hernias, distal catheter cuff extrusion and infections of the exit site or tunnel during surgery or the postoperative duration. No mortality was observed in this group of patients. The 6-month follow-up study showed 100% catheter-related complication-free survival. Our modified laparoscopic intra-abdominal fixation technique using suture passer hernia forceps is a simple and safe method for PD catheter placement and is effective in minimizing the risk of catheter migration.

Endometrial lesions caused by catheters used for embryo transfers: a preliminary report.

PubMed

Marconi, Guillermo; Vilela, Martín; Belló, José; Diradourián, Marco; Quintana, Ramiro; Sueldo, Carlos

2003-08-01

To visualize by microhysteroscopy any possible lesions on the endocervix and endometrium made by the catheters commonly used for embryo transfer (ET). Prospective descriptive study. Tertiary fertility center (IFER). Twenty-three infertile patients underwent a mock transfer before a microhysteroscopy during the postovulatory phase (days 2-5 after ovulation) of the cycle with a Tomcat catheter (n = 5), Frydman's catheter (n = 5), Frydman's set (n = 3), or Wallace's catheter (n = 10). Mock ETs and subsequent mycrohysteroscopies.Visualization, description, and documentation of endocervical and endometrial lesions. The lesions in all 23 patients were described and documented (tunnel-like, groove-like, punch-out, crater-like). The Wallace catheter appears to be less traumatic to the endometrium (but it seems that it is important to take care to not pass the internal os with the outer sheath). The Tomcat catheter and the Frydman's set caused the more significant lesions that were observed. In this preliminary study, for the first time endometrial lesions caused by the ET catheters were directly visualized and documented. Some of these observed lesions appear to be capable of compromising the success of ET.

Pulmonary vein stenosis following catheter ablation of atrial fibrillation.

PubMed

Pürerfellner, Helmut; Martinek, Martin

2005-11-01

This review provides an update on the mechanisms, incidence, and current management of significant pulmonary vein stenosis following catheter ablation of atrial fibrillation. Catheter ablation involving the pulmonary veins and the surrounding left atrial tissue is increasingly used to treat atrial fibrillation. In parallel with the fact that these procedures may cure a substantial proportion of patients, severe complications have been observed. Pulmonary vein stenosis is a new clinical entity produced by radiofrequency energy delivery mainly within or at the orifice of the pulmonary veins. The exact incidence is currently unknown because the diagnosis is dependent on the imaging modality and on the rigor with which patients are followed up. The optimal method for screening patients has not been determined. Stenosis of a pulmonary vein may be assessed by combining anatomic and functional imaging using computed tomographic or magnetic resonance imaging, transesophageal echocardiography, and lung scanning. Symptoms vary considerably and may be misdiagnosed, leading to severe clinical consequences. Current treatment strategies involve pulmonary vein dilatation or stenting; however, the restenosis rate remains high. The long-term outcome in patients with pulmonary vein stenosis is unclear. Strategies under development to prevent pulmonary vein stenosis include alternate energy sources and modified ablation techniques. Pulmonary vein stenosis following catheter ablation is a new clinical entity that has been described in various reports recently. There is much uncertainty with respect to causative factors, incidence, diagnosis, and treatment, and long-term sequelae are unclear.

Renal sympathetic denervation using an externally irrigated radiofrequency ablation catheter for treatment of resistant hypertension - Acute safety and short term efficacy.

PubMed

Yalagudri, Sachin; Raju, Narayana; Das, Bharati; Daware, Ashwin; Maiya, Shreesha; Jothiraj, Kannan; Ravikishore, A G

2015-01-01

This study was conducted to assess the acute safety and short term efficacy of renal sympathetic denervation (RSDN) using solid tip radiofrequency ablation (RFA) catheter and saline irrigation through the renal guiding catheter to achieve effective denervation. RSDN using a specialized solid-tip RFA catheter has recently been demonstrated to safely reduce systemic blood pressure in patients with refractory hypertension, the limitation being inadequate power delivery in renal arteries. So, we used solid-tip RFA catheter along with saline irrigation for RSDN. Nine patients with resistant hypertension underwent CT and conventional renal angiography, followed by bilateral or unilateral RSDN using 5F RFA catheter with saline irrigation through renal guiding catheter. Repeat renal angiography was performed at the end of the procedure. In all patients, pre- and post-procedure serum creatinine was measured. Over 1-month period: 1) the systolic/diastolic blood pressure decreased by -57 ± 20/-25 ± 7.5 mm Hg; 2) all patients experienced a decrease in systolic blood pressure of at least -36 mm Hg (range 36-98 mm Hg); 3) there was no evidence of renal artery injury immediate post-procedure. There was no significant change in serum creatinine level. This data shows the acute procedural safety and short term efficacy of RSDN using modified externally irrigated solid tip RFA catheter. Copyright © 2015 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

Single-stick tunneled central venous access using the jugular veins in infants weighing less than 5 kg.

PubMed

Lindquester, Will S; Hawkins, C Matthew; Monroe, Eric J; Gill, Anne E; Shivaram, Giridhar M; Seidel, F Glen; Lungren, Matthew P

2017-11-01

Despite the demonstrated feasibility of the single-stick technique in the femoral vein, its use in neonates and infants for placing central lines in internal and external jugular veins has not been reported. Describe and assess the safety and efficacy of tunneled jugular central venous catheter placement performed under ultrasound (US) and fluoroscopic guidance in neonates and infants weighing <5 kg using the single-stick technique at three tertiary pediatric hospitals. Thirty-three children weighing less than 5 kg received tunneled central venous access in either internal or external jugular veins using the single-stick technique. Patient history, procedural records and clinical follow-up documents were retrospectively reviewed. Complication rates were compared to those of 41 patients receiving single-stick femoral central lines. Technical complications occurred during one (3.0%) jugular placement with the patient having a failed right-side attempt with subsequent successful left-side placement. The catheters did not last the entire course of treatment in three (9.1%) patients with jugular lines. One patient had the catheter removed due to concern for infection, one catheter was accidentally removed during dressing changes, and one catheter was displaced and subsequently exchanged. Of patients receiving femoral central lines, 1 (2.4%) had a technical complication and 5 catheters (12.2%) did not last the entire course of treatment. The placement of tunneled central venous catheters in neonates/infants <5 kg is safe and technically feasible using the internal/external jugular vein via the single-stick technique. By theoretically reducing the risks of catheter infection by avoiding the diaper area and thrombosis by using larger veins, it may be preferable in certain patient populations.

Safety of latex urinary catheters for the short time drainage

PubMed Central

Hosseinpour, Mehrdad; Noori, Saeed; Amir-Beigi, Mahdieh; Pourfakharan, Mohammad Hassan; Ehteram, Hassan; Hamsayeh, Mohadese

2014-01-01

Background: In this study, we attempt to identify the most appropriate catheter (silicone vs. latex) for short-term urinary catheterization. We compared the post-operative clinico-pathological complications between latex and silicone for short term catheterization in rabbits with hypospadias. Materials and Methods: Forty rabbits were used in our study to compare complications of catheterization. They were divided in two groups. Hypospadias like defect was created by a 1 cm long excision of the ventral urethra. For urethroplasty, we used tubularized incised plate technique. Latex and silicon catheters were used in groups 1 and 2, respectively. Post-operatively, routine laboratory urine test and complications (allergy, infection, bleeding) were compared in groups. Results: A total of 40 rabbits underwent hypospadias repair. Findings showed that there were no significant differences between groups based on urine test indices (P = NS). Urinary tract infection rate was 10% (2 rabbits) in latex and 0% in silicone groups (P = NS). There were no significant differences between groups regarding of cystitis grades between study groups (P = NS). Conclusion: It seems that urinary tract catheterization with latex catheters is a safe, feasible, and in-expensive procedure for short-term post-operative course in hypospadias surgery in patients without latex hypersensitivity. PMID:25125890

Washout policies in long-term indwelling urinary catheterization in adults: a short version cochrane review.

PubMed

Sinclair, Lesley; Hagen, Suzanne; Cross, Stephen

2011-09-01

People requiring long-term bladder draining with an indwelling catheter can experience catheter blockage. Regimens involving different solutions can be used to wash out catheters with the aim of preventing blockage. To determine if certain washout regimens (including no washout) are better than others in terms of effectiveness, acceptability, complications, quality of life, and economics for the management of long-term indwelling urinary catheters in adults. We searched the Cochrane Incontinence Group Specialized Trials Register (searched April 30, 2009), MEDLINE (January 1966 to April 2009), MEDLINE In-Process (April 30, 2009), EMBASE (January 1980 to April 2009), and CINAHL (December 1981 to April 2009). Additionally, we examined all reference lists of identified trials and contacted manufacturers and researchers in the field. All randomized and quasi-randomized trials comparing catheter washout policies (e.g., washout vs. no washout, different washout solutions, frequency, duration, volume, concentration, method of administration) in adults (16 years and above) in any setting (i.e., hospital, nursing/residential home, community) with an indwelling urethral or suprapubic catheter in place for more than 28 days. Data were extracted by three reviewers independently and compared. Disagreements were resolved by discussion. Data were processed as described in the Cochrane Handbook. If the trial data were not fully reported, clarification was sought from the authors. For categorical outcomes, the numbers reporting an outcome were related to the numbers at risk in each group to derive a risk ratio (RR). For continuous outcomes, means, and standard deviations were used to derive weighted mean differences (WMD). No meta-analysis of study results was possible. Five trials met the inclusion criteria involving 242 patients (132 completed) in two cross-over and three parallel-group randomized controlled trials. Only three of the eight comparisons pre-stated in the review

Minimally invasive fluoroscopic percutaneous peritoneal dialysis catheter salvage.

PubMed

Narayan, Rajeev; Fried, Terrance; Chica, Gerardo; Schaefer, Mathew; Mullins, Daniel

2014-06-01

Peritoneal dialysis catheter (PDC) dysfunction can often be treated fluoroscopically by manipulation with wire, balloon or stiff stylet, saving surgical intervention for refractory cases. We describe an enhanced percutaneous approach to PDC salvage that can lead to a more definitive intervention and salvage for cases refractory to fluoroscopic manipulation. In five cases of PD catheter malfunction, the deep cuff was dissected free after a 0.035 hydrophilic wire was passed into the peritoneum through the PDC. Only the intraperitoneal portion of the PDC was explanted. The PDC was cleared of obstruction and omentum. The intraperitoneal portion of the PDC was reimplanted over wire via a peel-away sheath and the deep cuff sutured. Omental entrapment was present in three of five patients and fibrin occlusion in four of the five cases. All catheters were repaired successfully by the described technique. Post procedure, 3-5 days of lower volume, recumbent PD exchanges were performed prior to full-dose PD. No perioperative complications or leaks were noted. All PDCs were patent at 6 months. One patient required laparoscopy for recurrent omental wrapping 3 months post intervention. PDC salvage in this manner is a cost-effective alternative to laparoscopic repair of PDCs failing catheter manipulation. The infection barrier afforded by the original superficial cuff and subcutaneous tunnel is maintained. PD can be resumed immediately. Only refractory cases need laparoscopy. This procedure allows for a more definitive correction of catheter migration and obstruction, avoids placement of a new PDC or temporary hemodialysis, is cost-effective and expands percutaneous options for dysfunctional PD catheters.

Mucinous adenocarcinoma of the bladder associated with long term suprapubic tube: a case report.

PubMed

Bauman, Tyler M; Potretzke, Theodora A; Potretzke, Aaron M; Siegel, Cary L; Brandes, Steven B

2015-12-03

Chronic indwelling catheters may induce histologic changes within the bladder, and these changes are sometimes pre-malignant. There are many documented cases of squamous cell carcinoma associated with indwelling catheters, but only three cases of catheter-associated adenocarcinoma have been reported. In this case report, we present radiographic findings of a case of mucinous adenocarcinoma of the bladder and suprapubic (SP) tract in a quadriplegic patient. A 71-year-old male with a history of spinal cord injury presented with hematuria and SP discharge after SP catheterization for 51 years. CT urography was performed and revealed an irregular, infiltrative, and heterogeneous mass arising from the anterior bladder at the level of the suprapubic catheter and extending along the SP tube tract. Cystoscopy and biopsy revealed an adenocarcinoma of the anterior bladder and stoma with extensive associated mucin production and a background of acute and chronic inflammation. Surgical therapy included cystoprostatectomy, abdominal wall resection, ileal conduit creation, and abdominal wall reconstruction. The final diagnosis was a high-grade, T2a/N0/M0 (Stage II) mucinous adenocarcinoma of the bladder. There has been no evidence of tumor recurrence over the previous 5 years. Few cases of adenocarcinoma associated with long term indwelling catheter have been reported in the literature, and due to the rarity of this disease process, the prognosis with surgical therapy is not well known. The patient described herein has been free of recurrence for the previous five years, suggesting that surgery is a viable management option for these patients.

Comparison of three types of central venous catheters in patients with malignant tumor receiving chemotherapy

PubMed Central

Fang, Shirong; Yang, Jinhong; Song, Lei; Jiang, Yan; Liu, Yuxiu

2017-01-01

Background Central venous catheters (CVCs) have been an effective access for chemotherapy instead of peripherally intravenous catheters. There were limited studies on the choices and effects of different types of CVCs for chemotherapy. The aim of this study was to compare the complications, cost, and patients’ quality of life and satisfaction of three commonly used CVCs for chemotherapy, such as implanted venous port, peripherally inserted central catheters (PICCs), and external non-tunneled central venous catheters (NTCs). Methods A double-center prospective cohort study was carried out from March 2014 to December 2016. Catheterization situation, complications, catheter maintenance, cost, and patients’ quality of life and satisfaction were recorded, investigated, and analyzed. Forty-five ports, 60 PICCs and 40 NTCs were included. All the CVCs were followed up to catheter removal. Results There was no statistical difference in catheterization success rates between port and PICC. NTC had less success rate by one puncture compared with port. Ports had fewer complications compared with PICCs and NTCs. The complication rates of ports, PICCs and NTCs were 2.2%, 40%, and 27.5%, respectively. If the chemotherapy process was <12 months, NTCs cost least, and the cost of port was much higher than PICC and NTC. When the duration time was longer than 12 months, the cost of port had no difference with the cost of PICC. Quality of life and patients’ satisfaction of port group were significantly higher than the other two groups. Conclusion Although port catheterization costs more and needs professional medical staff and strict operational conditions, ports have fewer complications and higher quality of life and patients’ satisfaction than PICCs and NTCs. Therefore, not following consideration of the economic factor, we recommend port as a safe and an effective chemotherapy access for cancer patients, especially for whom needing long chemotherapy process. PMID:28744109

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.

Occlusion of a Long-Term Transpleural Biliary Drainage Tract Using a Gelatin Pledget (Hep-Plug™).

PubMed

Kortes, Nikolas; Gnutzmann, Daniel; Konietzke, Philip; Mayer, Philipp; Sumkauskaite, Migle; Kauczor, Hans-Ulrich; Radeleff, Boris A

2017-11-01

This case describes a technique used to close a long-term 14F transpleural biliary drainage catheter tract to prevent biliopleural fistula and further complications. We deployed a compressed gelatin foam pledget provided in a pre-loaded delivery device (Hep-Plug™) along the intrahepatic tissue tract for sealing it against the pleural cavity. The device used is easy to handle and gives the Interventional Radiologist the possibility to safely manage and prevent complications after percutaneous transhepatic interventions.

Improved methods for venous access: the Port-A-Cath, a totally implanted catheter system.

PubMed

Strum, S; McDermed, J; Korn, A; Joseph, C

1986-04-01

We prospectively evaluated the performance and rate of long-term complications with the Port-A-Cath (PAC), a totally implanted vascular access system. Two catheter styles were evaluated, a small-bore (SB) catheter (0.51-mm diameter) and a large-bore (LB) catheter (1.02-mm diameter), in conjunction with the use of a strict catheter care protocol. The PAC performed well, and with both SB and LB systems, no significant extravasation, skin necrosis, hematoma, septum damage or leakage, or subcutaneous portal infections occurred after 7,240 days of implantation and 1,435 days of use. Complications with the PAC system consisted of catheter occlusion (seven patients, 21.5%) and one instance of possible catheter infection (3.1%). Occlusions were limited to patients implanted with the SB catheter (seven of 16, 43.8%), and five of the seven (71.4%) occurred in patients receiving continuous infusion chemotherapy and/or total parenteral nutrition. Patency of the PAC system was maintained using a regular flushing schedule once every 30 days, a significant advantage compared with the daily maintenance schedule required with externally placed venous catheters. The results of this study suggest that the PAC system can provide a safe and reliable method for venous access in patients requiring intermittent or prolonged intravenous therapy.

Women's Experiences with and Preference for Induction of Labor with Oral Misoprostol or Foley Catheter at Term.

PubMed

Ten Eikelder, Mieke L G; van de Meent, Marieke M; Mast, Kelly; Rengerink, Katrien Oude; Jozwiak, Marta; de Graaf, Irene M; Scholtenhuis, Marloes A G Holswilder-Olde; Roumen, Frans J M E; Porath, Martina M; van Loon, Aren J; van den Akker, Eline S; Rijnders, Robbert J P; Feitsma, A Hanneke; Adriaanse, Albert H; Muller, Moira A; de Leeuw, Jan W; Visser, Harry; Woiski, Mallory D; Weerd, Sabina Rombout-de; van Unnik, Gijs A; Pernet, Paula J M; Versendaal, Hans; Mol, Ben W; Bloemenkamp, Kitty W M

2017-01-01

Objective  We assessed experience and preferences among term women undergoing induction of labor with oral misoprostol or Foley catheter. Study Design  In 18 of the 29 participating hospitals in the PROBAAT-II trial, women were asked to complete a questionnaire within 24 hours after delivery. We adapted a validated questionnaire about expectancy and experience of labor and asked women whether they would prefer the same method again in a future pregnancy. Results  The questionnaire was completed by 502 (72%) of 695 eligible women; 273 (54%) had been randomly allocated to oral misoprostol and 229 (46%) to Foley catheter. Experience of the duration of labor, pain during labor, general satisfaction with labor, and feelings of control and fear related to their expectation were comparable between both the groups. In the oral misoprostol group, 6% of the women would prefer the other method if induction is necessary in future pregnancy, versus 12% in the Foley catheter group (risk ratio: 0.70; 95% confidence interval: 0.55-0.90; p =  0.02). Conclusion  Women's experiences of labor after induction with oral misoprostol or Foley catheter are comparable. However, women in the Foley catheter group prefer more often to choose a different method for future inductions. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Catheter-based photoacoustic endoscope

PubMed Central

Yang, Joon-Mo; Li, Chiye; Chen, Ruimin; Zhou, Qifa; Shung, K. Kirk; Wang, Lihong V.

2014-01-01

Abstract. We report a flexible shaft-based mechanical scanning photoacoustic endoscopy (PAE) system that can be potentially used for imaging the human gastrointestinal tract via the instrument channel of a clinical video endoscope. The development of such a catheter endoscope has been an important challenge to realize the technique’s benefits in clinical settings. We successfully implemented a prototype PAE system that has a 3.2-mm diameter and 2.5-m long catheter section. As the instrument’s flexible shaft and scanning tip are fully encapsulated in a plastic catheter, it easily fits within the 3.7-mm diameter instrument channel of a clinical video endoscope. Here, we demonstrate the intra-instrument channel workability and in vivo animal imaging capability of the PAE system. PMID:24887743

Central Vein Dilatation Prior to Concomitant Port Implantation

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

Krombach, Gabriele A., E-mail: krombach@rad.rwth-aachen.de; Plumhans, Cedric; Goerg, Fabian

2010-04-15

Implantation of subcutaneous port systems is routinely performed in patients requiring repeated long-term infusion therapy. Ultrasound- and fluoroscopy-guided implantation under local anesthesia is broadly established in interventional radiology and has decreased the rate of complications compared to the surgical approach. In addition, interventional radiology offers the unique possibility of simultaneous management of venous occlusion. We present a technique for recanalization of central venous occlusion and angioplasty combined with port placement in a single intervention which we performed in two patients. Surgical port placement was impossible owing to occlusion of the superior vena cava following placement of a cardiac pacemaker andmore » occlusion of multiple central veins due to paraneoplastic coagulopathy, respectively. In both cases the affected vessel segments were dilated with balloon catheters and the port systems were placed thereafter. After successful dilatation, the venous access was secured with a 25-cm-long, 8-Fr introducer sheath, a subcutaneous pocket prepared, and the port catheter tunneled to the venipuncture site. The port catheter was introduced through the sheath with the proximal end connected to a 5-Fr catheter. This catheter was pulled through the tunnel in order to preserve the tunnel and, at the same time, allow safe removal of the long sheath over the wire. The port system functioned well in both cases. The combination of recanalization and port placement in a single intervention is a straightforward alternative for patients with central venous occlusion that can only be offered by interventional radiology.« less

Randomized Controlled Trial Comparing Open Versus Laparoscopic Placement of a Peritoneal Dialysis Catheter and Outcomes: The CAPD I Trial.

PubMed

van Laanen, Jorinde H H; Cornelis, Tom; Mees, Barend M; Litjens, Elisabeth J; van Loon, Magda M; Tordoir, Jan H M; Peppelenbosch, Arnoud G

2018-01-01

had a paramedian wound infection. In the laparoscopic group, 1 patient had a transient cardiac event, 1 patient had intraabdominal bleeding requiring reoperation, and 1 patient had fluid leakage that could be managed conservatively. The survival curve demonstrated a good long-term function of PD. This randomized controlled trial (RCT) comparing open vs laparoscopic placement of PD catheters demonstrates equal clinical success rates between the 2 techniques. Advanced laparoscopic techniques such as catheter fixation techniques and omentopexy might further improve clinical outcome. Copyright © 2018 International Society for Peritoneal Dialysis.

Contact force monitoring during catheter ablation of intraatrial reentrant tachycardia in patients with congenital heart disease.

PubMed

Krause, Ulrich; Backhoff, David; Klehs, Sophia; Schneider, Heike E; Paul, Thomas

2016-08-01

Monitoring of catheter contact force during catheter ablation of atrial fibrillation has been shown to increase efficacy and safety. However, almost no data exists on the use of this technology in catheter ablation of intraatrial reentrant tachycardia in patients with congenital heart disease. The aim of the present study was to evaluate the impact of contact force monitoring during catheter ablation of intraatrial reentrant tachycardia in those patients. Catheter ablation of intraatrial reentrant tachycardia using monitoring of catheter contact force was performed in 28 patients with congenital heart disease (CHD). Thirty-two patients matched according to gender, age, and body weight with congenital heart disease undergoing catheter ablation without contact force monitoring served as control group. Parameters reflecting acute procedural success, long-term efficacy, and safety were compared. Acute procedural success was statistically not different in both groups (contact force 93 % vs. control 84 %, p = 0.3). Likewise the recurrence rate 1 year after ablation as shown by Kaplan-Meier analysis did not differ (contact force 28 % vs. control 37 %, p = 0.63). Major complications were restricted to groin vessel injuries and occurred in 3 out of 60 patients (contact force n = 1; control n = 2). Complications related to excessive catheter contact force were not observed. The present study did not show superiority of catheter contact force monitoring during ablation of intraatrial reentrant tachycardia in patients with CHD in terms of efficacy and safety. Higher contact force compared to pulmonary vein isolation might therefore be required to increase the efficacy of catheter ablation of intraatrial reentrant tachycardia in patients with congenital heart disease.

Concurrent myotomy and tunneling after establishment of a half tunnel instead of myotomy after establishment of a full tunnel: a more efficient method of peroral endoscopic myotomy.

PubMed

Philips, George M; Dacha, Sunil; Keilin, Steve A; Willingham, Field F; Cai, Qiang

2016-04-01

Peroral endoscopic myotomy (POEM) is a time-consuming and challenging procedure. Traditionally, the myotomy is done after the submucosal tunnel has been completed. Starting the myotomy earlier, after submucosal tunneling is half completed (concurrent myotomy and tunneling), may be more efficient. This study aims to assess if the method of concurrent myotomy and tunneling may decrease the procedural time and be efficacious. This is a retrospective case series of patients who underwent modified POEM (concurrent myotomy and tunneling) or traditional POEM at a tertiary care medical center. Modified POEM or traditional POEM was performed at the discretion of the endoscopist in patients presenting with achalasia. The total procedural duration, myotomy duration, myotomy length, and time per unit length of myotomy were recorded for both modified and traditional POEM. Modified POEM was performed in 6 patients whose mean age (± standard deviation [SD]) was 58 ± 13.3 years. Of these, 5 patients had type II achalasia and 1 patient had esophageal dysmotility. The mean Eckardt score (± SD) before the procedure was 8.8 ± 1.3. The modified technique was performed in 47 ± 8 minutes, with 6 ± 1 minutes required per centimeter of myotomy and 3 ± 1 minutes required per centimeter of submucosal space. The Eckardt score was 3 ± 1.1 at 1 month and 3 ± 2.5 at 3 months. The procedure time for modified POEM was significantly shorter than that for traditional POEM. Modified POEM with short submucosal tunneling may be more efficient than traditional POEM with long submucosal tunneling, and outcomes may be equivalent over short-term follow-up. Long-term data and randomized controlled studies are needed to compare the clinical efficacy of modified POEM with that of the traditional method.

Rational choice of peritoneal dialysis catheter.

PubMed

Dell'Aquila, Roberto; Chiaramonte, Stefano; Rodighiero, Maria Pia; Spanó, Emilia; Di Loreto, Pierluigi; Kohn, Catalina Ocampo; Cruz, Dinna; Polanco, Natalia; Kuang, Dingwei; Corradi, Valentina; De Cal, Massimo; Ronco, Claudio

2007-06-01

The peritoneal catheter should be a permanent and safe access to the peritoneal cavity. Catheter-related problems are often the cause of permanent transfer to hemodialysis (HD) in up to 20% of peritoneal dialysis (PD) patients; in some cases, these problems require a temporary period on HD. Advances in connectology have reduced the incidence of peritonitis, and so catheter-related complications during PD have become a major concern. In the last few years, novel techniques have emerged in the field of PD: new dialysis solutions, better connectology, and cyclers for automated PD. However, extracorporeal dialysis has continued to improve in terms of methods and patient survival, but PD has failed to do so. The main reason is that peritoneal access has remained problematical. The peritoneal catheter is the major obstacle to wide-spread use of PD. Overcoming catheter-related problems means giving a real chance to development of the peritoneal technique. Catheters should be as efficient, safe, and acceptable as possible. Since its introduction in the mid-1960s, the Tenckhoff catheter has not become obsolete: dozens of new models have been proposed, but none has significantly reduced the pre-dominance of the first catheter. No convincing prospective data demonstrate the superiority of any peritoneal catheter, and so it seems that factors other than choice of catheter are what affect survival and complication rates. Efforts to improve peritoneal catheter survival and complication rates should probably focus on factors other than the choice of catheter. The present article provides an overview of the characteristics of the best-known peritoneal catheters.

21 CFR 880.5200 - Intravascular catheter.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Devices § 880.5200 Intravascular catheter. (a) Identification. An intravascular catheter is a device that consists of a slender tube and any necessary connecting fittings and that is inserted into the patient's vascular system for short term use (less than 30 days) to sample blood, monitor blood pressure, or...

[Urinary catheters prevalence study in a university hospital].

PubMed

Carrouget, J; Legeay, C; Poirier, A; Azzouzi, A-R; Zahar, J-R; Bigot, P

2017-04-01

Urinary tract infection is the most common healthcare-association infection, especially because of urinary catheter. We evaluated our practices concerning catheter insertion and management in our institution. We conducted a single-centre descriptive cross-sectional study during 1 week in September 2014 in all adult departments. We noted prevalence, indications, length, management of urinary catheter (UC) and symptomatic catheter-associated urinary tract infections (SCAUTI). Amongst 1046 patients audited, 125 (12%) had UC. The mean age was 72 years (64.8-79.2). UC prevalence was higher in surgical (88%) and medical (87%) intensive care, urology (50%), geriatrics (18%) and long-term care (18%) departments. The average catheterisation length was 7.8 days (3.8-11.8); it was shorter in surgery than in medicine departments (3.6 vs 9.7 days, P<0.001). Catheters were present for more than 4 days in 60% of the cases. Acute urinary retention was the most frequent indication (59%), significantly more in medical than surgical departments (75% vs 26%). Others indications were perioperative (17%), diuresis monitoring (12%), strict immobilization (4%) and unnecessary indications or staff comfort (4%). A SCAUTI was present in 10% of cases, mostly in medicine department (30% vs 8%). The prevalence of our institution is higher than the national prevalence (8.1%), but still below the European average (17.2%). Control of the risk of CAUTI requires compliance with UC appropriate indications, UC management, and prompt removal of unnecessary UC. 4. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Micrococcus-associated central venous catheter infection in patients with pulmonary arterial hypertension.

PubMed

Oudiz, Ronald J; Widlitz, Allison; Beckmann, X Joy; Camanga, Daisy; Alfie, Jose; Brundage, Bruce H; Barst, Robyn J

2004-07-01

To determine the incidence of catheter-related infection in patients with pulmonary arterial hypertension (PAH) receiving epoprostenol (EPO), and to note an etiologic role for Micrococcus spp, which is rarely reported as a pathogen in the medical literature. Observational study. Two PAH specialty treatment centers, Harbor-UCLA Medical Center (Torrance, CA), and the College of Physicians and Surgeons, Columbia University (New York, NY). A total of 192 patients with PAH receiving continuous therapy with IV EPO. From 1987 to 2000, 192 patients with PAH received infusions of EPO via central venous catheter. Catheter care included regular dressing changes with dry gauze using a sterile procedure, without the use of flushes. Patients were asked to report on known infections and treatments, and symptoms. All infections were verified by a telephone call to the patient, care provider, and microbiology laboratory whenever possible. There were 335,285 catheter days (mean +/- SD, 1,325 +/- 974 catheter days). There were 88 clinical catheter infections with 51 blood culture-positive infections, necessitating catheter removal in 38 instances. The following pathogens were isolated: Staphylococcus aureus (25); Micrococcus spp (14); mixed flora (3); coagulase-negative Staphylococcus spp (2); Corynebacterium spp (2); Serratia marcessens (1); Enterobacter spp (1); Pseudomonas aeruginosa (1); enterococci (1); and unidentified Gram-positive cocci (1). The catheter infection rate was 0.26 per 1,000 catheter days. The use of long-term therapy with continuous EPO appears to be associated with a low incidence of catheter-related infections. Micrococcus spp were the second most common etiologic agent. Caregivers managing patients with PAH must be aware of the risk of catheter infection, as it may contribute to the morbidity and mortality associated with the use of EPO. When isolated, Micrococcus spp should not be viewed as a contaminant, but rather as a true pathogen that may require

Test method for mechanical properties of implantable catheters according to DIN 10555-3.

PubMed

Busch, J D; Schröder, H; Sellenschloh, K; Adam, G; Ittrich, H; Huber, G

2018-06-01

To enable causal analysis of port catheter failure, this study aimed to develop an experimental setup for uniaxial tensile tests that addresses the specific requirements of highly elastic medical catheters; and to quantify parameters of the catheters' mechanical competence with respect to effects of artificial aging. Segments of 6F-polyurethane catheters were tested in their native status, after chemical and after mechanical aging. Tension experiments were performed with a rate of 220 mm/min until catheter failure. Material behavior was analyzed based on load cell measurements of the universal test system and an additional optical distance registration. The Young's modulus, the ultimate stress and the ultimate strain were determined. Chemical aging significantly decreased Young's modulus (84%; p = 0.001) and ultimate stress (83%; p < 0.001), whereas mechanical aged samples demonstrated similar results for the Young's modulus (p = 0.772) and a non-significant rise of ultimate stress (13%; p = 0.128). Ultimate strain did not differ significantly regardless of the pretreatment. The results proof reliability, reproducibility and sensitivity to quantify artificial aging induced variations and also promise to detect deviations in material features caused by long-term clinical usage of catheters. Copyright © 2018 Elsevier Ltd. All rights reserved.

Previous PICC Placement May Be Associated With Catheter-Related Infections in Hemodialysis Patients

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

Butler, Philip J., E-mail: philip.butler@yale.edu; Sood, Shreya; Mojibian, Hamid

2011-02-15

Background: Catheter-related infections (CRIs) are a significant source of morbidity and mortality in hemodialysis patients. The identification of novel, modifiable risk factors for CRIs may lead to improved outcomes in this population. Peripherally inserted central catheters (PICCs) have been hypothesized to compromise vascular access due to vascular damage and venous thrombosis, whereas venous thrombosis has been linked to the development of CRIs. Here we examine the association between PICC placement and CRIs. Methods: A retrospective review was performed of all chronic hemodialysis catheter placements and exchanges performed at a large university hospital from September 2003 to September 2008. History ofmore » PICC line use was determined by examining hospital radiologic records from December 1993 to September 2008. Catheter-related complications were assessed and correlated with PICC line history. Results: One hundred eighty-five patients with 713 chronic tunneled hemodialysis catheter placements were identified. Thirty-eight of those patients (20.5%) had a history of PICC placement; these patients were more likely to have CRIs (odds ratio = 2.46, 95% confidence interval = 1.71-3.53, p < .001) compared with patients without a history of PICC placement. There was no difference between the two groups in age or number of catheters placed. Conclusion: Previous PICC placement may be associated with catheter-related infections in hemodialysis patients.« less

Complications of Peripherally Inserted Central Venous Catheters: A Retrospective Cohort Study

PubMed Central

Jose Amo-Setién, Francisco; Herrero-Montes, Manuel; Olavarría-Beivíde, Encarnación; Rodríguez-Rodríguez, Mercedes; Torres-Manrique, Blanca; Rodríguez-de la Vega, Carlos; Caso-Álvarez, Vanesa; González-Parralo, Laura

2016-01-01

Background and Aim The use of venous catheters is a widespread practice, especially in oncological and oncohematological units. The objective of this study was to evaluate the complications associated with peripherally inserted central catheters (PICCs) in a cohort of patients. Materials and Methods In this retrospective cohort study, we included all patient carrying PICCs (n = 603) inserted at our institute between October 2010 and December 2013. The main variables collected were medical diagnosis, catheter care, location, duration of catheterization, reasons for catheter removal, complications, and nursing care. Complications were classified as infection, thrombosis, phlebitis, migration, edema, and/or ecchymosis. Results All patients were treated according to the same “nursing care” protocol. The incidence rate of complications was two cases per 1000 days of catheter duration. The most relevant complications were infection and thrombosis, both with an incidence of 0.17 cases per 1000 days of the total catheterization period. The total average duration of catheterization was 170 days [SD 6.06]. Additionally to “end of treatment” (48.42%) and “exitus”, (22.53%) the most frequent cause of removal was migration (displacement towards the exterior) of the catheter (5.80%). Conclusions PICCs are safe devices that allow the administration of long-term treatment and preserve the integrity of the venous system of the patient. Proper care of the catheter is very important to improve the quality life of patients with oncologic and hematologic conditions. Therefore, correct training of professionals and patients as well as following the latest scientific recommendations are particularly relevant. PMID:27588946

Embryo Transfer Catheters: Softer is Easier.

PubMed

Ruhlmann, Claudio; Gnocchi, Diego C; Cattaneo, Antonio R; Molina, Lucas G; Rivadeneira, Luciano Ruiz; Tessari, Lautaro; Martínez, Alejandro G

2015-11-01

This study aimed to compare the use of semi-rigid and flexible catheters in terms of pregnancy rate and level of difficulty of the embryo transfer (ET) procedure. Seven hundred and thirty-nine consecutive follicular aspirations for IVF or ICSI performed in our private fertility clinic within a 30-month period were randomly divided into two groups. Patients were allocated to either of the groups at the time of follicular retrieval with the aid of a random number generator according to the catheter used in ET: Group 1 (n = 370) - Frydman Classic Catheter 4.5 catheters; and Group 2 (n = 369) - Frydman Ultrasoft 4.5 catheters. Only patients offered ET in the randomized cycle were included (Group 1 = 363 and Group 2 = 340). Patients did not change groups after catheter allocation. Statistical analysis was carried out using an unpaired t-test or a chi square test as appropriate. Differences with P<0.05 were considered. A statistically significant difference in favor of the use of the Ultrasoft catheter was evident for parameters use of a tenaculum (19.8% vs. 5.9%) or a hysterometer (5.0% vs. 1.2%), presence of blood during post-ET inspection of the catheter (9.9% vs. 3.8%), and implantation rate (13.0% vs. 16.4%). Clinical pregnancy and delivery rates were comparable in both groups. Our results suggest that a softer catheter may help with difficult ETs. Softer catheters, as also reported by other authors, resulted in better implantation rates.

Estimating Tunnel Strain in the Weak and Schistose Rock Mass Influenced by Stress Anisotropy: An Evaluation Based on Three Tunnel Cases from Nepal

NASA Astrophysics Data System (ADS)

Panthi, Krishna Kanta; Shrestha, Pawan Kumar

2018-06-01

Total plastic deformation in tunnels passing through weak and schistose rock mass consists of both time-independent and time-dependent deformations. The extent of this total deformation is heavily influenced by the rock mass deformability properties and in situ stress condition prevailing in the area. If in situ stress is not isotropic, the deformation magnitude is not only different along the longitudinal alignment but also along the periphery of the tunnel wall. This manuscript first evaluates the long-term plastic deformation records of three tunnel projects from the Nepal Himalaya and identifies interlink between the time-independent and time-dependent deformations using the convergence law proposed by Sulem et al. (Int J Rock Mech Min Sci Geomech 24(3):145-154, 1987a, Int J Rock Mech Min Sci Geomech 24(3):155-164, 1987b). Secondly, the manuscript attempts to establish a correlation between plastic deformations (tunnel strain) and rock mass deformable properties, support pressure and in situ stress conditions. Finally, patterns of time-independent and time-dependent plastic deformations are also evaluated and discussed. The long-term plastic deformation records of 24 tunnel sections representing four different rock types of three different headrace tunnel cases from Nepal Himalaya are extensively used in this endeavor. The authors believe that the proposed findings will be a step further in analysis of plastic deformations in tunnels passing through weak and schistose rock mass and along the anisotropic stress conditions.

The effect of peripherally inserted central catheter (PICC) valve technology on catheter occlusion rates--the 'ELeCTRiC' study.

PubMed

Johnston, Andrew J; Streater, Carmel T; Noorani, Remy; Crofts, Joanne L; Del Mundo, Aldwin B; Parker, Richard A

2012-01-01

Peripherally Inserted Central Catheters (PICCs) are increasingly being used to provide short to medium-term central venous access. The current study was designed to test the hypothesis that PICC valve technology does not influence PICC occlusion rates. Intensive care unit (ICU) patients who required a PICC were randomized to one of three types of dual lumen PICC (open ended non-valved, Groshong valve, PASV valve). PICC occlusions were recorded and managed with a protocol that used urokinase. A total of 102 patients were recruited to the study. The overall risk of occlusion per catheter was 35% (95% CI 26% to 44%). The overall rate of occlusion was 76 occlusions per 1000 catheter days (95% CI 61 to 95). Presence or type of valve did not significantly influence this rate (open-ended non-valved PICC 38% of catheters, 79 occlusions per 1000 catheter days; Groshong 38% of catheters, 60 occlusions per 1000 catheter days; PASV 27% of catheters, 99 occlusions per 1000 catheter days). The dose of urokinase required to treat PICC occlusions did not significantly differ between PICC types. Valved PICCs do not appear to influence PICC occlusion rates.

Efficacy of Minocycline and EDTA Lock Solution in Preventing Catheter-Related Bacteremia, Septic Phlebitis, and Endocarditis in Rabbits

PubMed Central

Raad, Issam; Hachem, Ray; Tcholakian, Robert K.; Sherertz, Robert

2002-01-01

To determine the efficacy of antibiotic catheter lock solution in preventing catheter-related infections, silicone catheters were tunneled and inserted into the jugular veins of 18 rabbits. The catheters were challenged with an intraluminal injection of 105 CFU of slime-producing Staphylococcus epidermidis in 0.1 ml of water. The catheters were maintained on heparin (100 IU/ml) flush for the first 3 days. On day 3, quantitative blood samples for culture were obtained from the catheters and ear veins, which documented catheter-related bacteremia, and the rabbits were randomized to have their catheters flushed as follows: five animals were continued on heparin (100 IU/ml), five animals received vancomycin (3 mg/ml) with heparin (100 IU/ml), and eight animals received 3 mg of minocycline per ml with 30 mg of EDTA per ml (M-EDTA). All animals were killed at day 7. Blood, catheters, jugular veins, and heart valves were cultured quantitatively. Animals maintained on heparin developed catheter-related colonization, bacteremia, septic phlebitis, and endocarditis. Vancomycin-heparin partially prevented catheter colonization, bacteremia, and phlebitis (P = 0.2). M-EDTA completely prevented catheter colonization, catheter-related bacteremia, and phlebitis in all of the animals (P < 0.01). Tricuspid endocarditis was equally prevented by vancomycin-heparin and M-EDTA (P ≤ 0.06). In conclusion, the M-EDTA catheter flush solution was highly efficacious in preventing catheter-related colonization, bacteremia, septic phlebitis, and endocarditis in rabbits. PMID:11796338

[An efficient strategy to decrease the central venous catheter-related adverse events rate in haemodialysis patients].

PubMed

Jean, Guillaume; Vanel, Thierry; Bresson, Eric; Terrat, Jean-Claude; Hurot, Jean-Marc; Lorriaux, Christie; Mayor, Brice; Chazot, Charles

2009-07-01

Catheter-related adverse events (CAE) remain a major cause of mortality and morbidity. We aimed to compare the CAE prevalence and adverse events rate at 10 years interval in one centre using different devices, dressing procedures. We compared two periods, from 1994 to 1997 (period 1) and from 2004 to 2007 (period 2). We recorded all prevalent tunnelled CAE and their related adverse event rate: catheter-related bacteraemia (CRB), catheter local infection (CLI), catheter dysfunction leading to CAE exchange, thrombolytic use and spontaneous pulling up. In period 1, PermCath catheter (Quinton, N=63) and TwinCath catheter (MedComp, N=76) were used in 95 HD. BioFlex catheter (N=52) and ASPC split catheter (MedComp, N=52) were used in 72 HD in period 2. In period 1, we performed catheter dressing using povidone iodine versus alcoholic chlorexidine in period 2. Between period 1 and period 2, the CAE prevalence decreased from 15-18% to 9-6%, CRB from 1.1 to 0.23/1000 day-catheter (p<0.001), CLI from 1.1 to 0.28/1000 day-catheter (p<0.001), definitive dysfunction from 12 to 1.2% (p<0.001) and CAE pulling up from 4 to 0%. The annual urokinase consumption decreased from three to one unit per CAE. This study shows the dramatic decrease in CAE prevalence (-50%) and related-adverse events (approximately -200%) since 10 years. Switching povidone iodine to chlorexidine and using more recent catheter devices appear very efficient in decreasing catheter-related adverse events.

[Testing methods for the characterization of catheter balloons and lumina].

PubMed

Werner, C; Rössler, K; Deckert, F

1995-10-01

The present paper reports on the characterization of catheter balloons and lumina on the basis of such known parameters as residual volume, compliance, burst pressure and flow rate, with the aim of developing standards, test methods and testing equipment as well as standards. These are becoming ever more important with the coming into force of the EC directive on medical products [7] and the law governing medical products in Germany [13], which requires manufacturers to specify the properties of their products. Our testing concept is based on a commercially available machine that subjects materials to alternating extension and compression forces over the long-term, to which we added a special hydraulic module. Using the multimedia technology we achieved a real time superimposition of the volume-diameter curve on the balloon. The function of the testing device and method is demonstrated on dilatation catheters. Our initial results reveal compatibility with the requirements of the 1% accuracy class. Use of this methodology for comparative testing of catheters and quality evaluation is recommended.

Long-axis view for ultrasound-guided central venous catheter placement via the internal jugular vein.

PubMed

Mahan, Angel F; McEvoy, Matthew D; Gravenstein, Nikolaus

2016-04-01

In modern practice, real-time ultrasound guidance is commonly employed for the placement of internal jugular vein catheters. With a new tool, such as ultrasound, comes the opportunity to refine and further optimize the ultrasound view during jugular vein catheterization. We describe jugular vein access techniques and use the long-axis view as an alternative to the commonly employed short-axis cross-section view for internal jugular vein access and cannulation. The long-axis ultrasound-guided internal jugular vein approach for internal jugular vein cannulation is a useful alternative technique that can provide better needle tip and guidewire visualization than the more traditional short-axis ultrasound view.

Central vein perforation during tunneled dialysis catheter insertion: principles of acute management.

PubMed

Pua, Uei

2014-10-01

Central venous perforation during dialysis catheter insertion is a potentially fatal complication. Prompt recognition and judicious initial steps are important in optimizing the outcome. The purpose of this manuscript is to illustrate the imaging features and steps in initial management. © 2014 International Society for Hemodialysis.

Origin of Long-Term Storage Stability and Nitric Oxide Release Behavior of CarboSil Polymer Doped with S-Nitroso-N-acetyl-D-penicillamine.

PubMed

Wo, Yaqi; Li, Zi; Brisbois, Elizabeth J; Colletta, Alessandro; Wu, Jianfeng; Major, Terry C; Xi, Chuanwu; Bartlett, Robert H; Matzger, Adam J; Meyerhoff, Mark E

2015-10-14

The prolonged and localized delivery of nitric oxide (NO), a potent antithrombotic and antimicrobial agent, has many potential biomedical applications. In this work, the origin of the long-term storage stability and sustained NO release mechanism of S-nitroso-N-acetyl-D-penicillamine (SNAP)-doped CarboSil 20 80A polymer, a biomedical thermoplastic silicone-polycarbonate-urethane, is explored. Long-term (22 days) localized NO release is achieved by utilizing a cross-linked silicone rubber as topcoats, which can greatly reduce the amount of SNAP, NAP, and NAP disulfide leaching from the SNAP-doped CarboSil films, as measured by LC-MS. Raman spectroscopy and powder X-ray diffraction characterization of SNAP-doped CarboSil films demonstrate that a polymer-crystal composite is formed during the solvent evaporation process when SNAP exceeds its solubility in CarboSil (ca. 3.4-4.0 wt %). Further, when exceeding this solubility threshold, SNAP exists in an orthorhombic crystal form within the bulk of the polymer. The proposed mechanism of sustained NO release in SNAP-doped CarboSil is that the solubilized SNAP in the polymer matrix decomposes and releases NO, primarily in the water-rich regions near the polymer/solution interface, and the dissolved SNAP in the bulk polymeric phase becomes unsaturated, resulting in the dissolution of crystalline SNAP within the bulk of the polymer. This is a very slow process that ultimately leads to NO release at the physiological flux levels for >3 weeks. The increased stability of SNAP within CarboSil is attributed to the intermolecular hydrogen bonds between the SNAP molecules that crystallize. This crystallization also plays a key role in maintaining RSNO stability within the CarboSil polymer for >8 months at 37 °C (88.5% remains). Further, intravascular catheters fabricated with this new material are demonstrated to significantly decrease the formation of Staphylococcus aureus biofilm (a leading cause of nosocomial bloodstream

Tissue adhesion to bioactive glass-coated silicone tubing in a rat model of peritoneal dialysis catheters and catheter tunnels.

PubMed

Ross, Edward A; Batich, Christopher D; Clapp, William L; Sallustio, Judith E; Lee, Nadeen C

2003-02-01

Silicone peritoneal dialysis catheters do not develop tissue ingrowth, lack a mechanical barrier to periluminal bacterial migration and need cuffs for anchorage. We hypothesized that a bioactive glass coating composed of silicon, calcium, sodium and phosphorous oxides would cause a beneficial tissue reaction causing catheter adhesion, and tested this in a rat model. A hexane solvent-based method of coating silicone tubes with Bioglass powder was used, which maintained flexibility, and then the ultrastructure was confirmed with scanning electron microscopy (EM). Segments 2.5 cm were implanted subcutaneously in 8 Sprague-Dawley rats, with uncoated tubes as a contralateral control, and histology was done at 2, 4 and 6 weeks, including special stains and EM. The uncoated segments grossly had no adherence to surrounding tissue, and were physically separate from a thin fibrous capsule of approximately 50 micro width. Trichrome stains demonstrated the capsule was rich in collagen. There was minimal adjacent tissue reaction. In contrast, the coated tubes were palpably fixed to the soft tissues, and sections demonstrated an adjacent prominent layer of macrophages and multinucleated giant cells. Small numbers of lymphocytes were noted. This cellular reaction increased over the 6-week implant duration, and was also associated with neovascularization of the tissue adjacent to the segments (33 vessels in coated vs. 20 in controls per x 200 field, P < 0.0001). Many refractile silicone particles and prominent multinucleated giant cells were present, with small numbers of lymphocytes and macrophages. Stains showed scattered discontinuous calcific deposits. These findings are consistent with reports that the Bioglass(R) silicon oxide leads to the formation of a layer of hydroxyapatite, which binds to collagen and induces a tissue cellular reaction. In summary, bioactive glass coatings can improve the tissue retention of silicone tubing by promoting adhesion by collagen and cell

Concurrent myotomy and tunneling after establishment of a half tunnel instead of myotomy after establishment of a full tunnel: a more efficient method of peroral endoscopic myotomy

PubMed Central

Philips, George M.; Dacha, Sunil; Keilin, Steve A.; Willingham, Field F.; Cai, Qiang

2016-01-01

Background and study aims: Peroral endoscopic myotomy (POEM) is a time-consuming and challenging procedure. Traditionally, the myotomy is done after the submucosal tunnel has been completed. Starting the myotomy earlier, after submucosal tunneling is half completed (concurrent myotomy and tunneling), may be more efficient. This study aims to assess if the method of concurrent myotomy and tunneling may decrease the procedural time and be efficacious. Patients and methods: This is a retrospective case series of patients who underwent modified POEM (concurrent myotomy and tunneling) or traditional POEM at a tertiary care medical center. Modified POEM or traditional POEM was performed at the discretion of the endoscopist in patients presenting with achalasia. The total procedural duration, myotomy duration, myotomy length, and time per unit length of myotomy were recorded for both modified and traditional POEM. Results: Modified POEM was performed in 6 patients whose mean age (± standard deviation [SD]) was 58 ± 13.3 years. Of these, 5 patients had type II achalasia and 1 patient had esophageal dysmotility. The mean Eckardt score (± SD) before the procedure was 8.8 ± 1.3. The modified technique was performed in 47 ± 8 minutes, with 6 ± 1 minutes required per centimeter of myotomy and 3 ± 1 minutes required per centimeter of submucosal space. The Eckardt score was 3 ± 1.1 at 1 month and 3 ± 2.5 at 3 months. The procedure time for modified POEM was significantly shorter than that for traditional POEM. Conclusions: Modified POEM with short submucosal tunneling may be more efficient than traditional POEM with long submucosal tunneling, and outcomes may be equivalent over short-term follow-up. Long-term data and randomized controlled studies are needed to compare the clinical efficacy of modified POEM with that of the traditional method. PMID:27092318

Guidewire Catheter Exchange in Pediatric Oncology: Indications, Postoperative Complications, and Outcomes.

PubMed

Fernandez-Pineda, I; Ortega-Laureano, L; Wu, H; Wu, J; Sandoval, J A; Rao, B N; Shochat, S J; Davidoff, A M

2016-06-01

Maintaining long-term central venous catheters (CVCs) in children undergoing chemotherapy can be challenging. Guidewire catheter exchange (GCE) replaces a CVC without repeat venipuncture. This study evaluated the indications, success rate, and complications of GCE in a large cohort of pediatric cancer patients. Medical records of pediatric cancer patients who underwent GCE at our institution between 2003 and 2013 were retrospectively reviewed. Variables analyzed included gender, age at GCE, primary cancer diagnosis, indication for GCE, absolute neutrophil count (ANC) at GCE, vein used, success rate, and postoperative complications (<30 days after exchange). A total of 435 GCEs performed in 407 patients (230 males and 177 females) were reviewed. Median age at GCE was 8 years (range, 0.2-24). Acute lymphoblastic leukemia was the most common diagnosis (50.6%). The primary indication for GCE was the desire to have an alternative type of CVC (71%). Other indications included catheter displacement (17%), catheter malfunction (11%), and catheter infection (1%). Median ANC at GCE was 2,581/mm(3) (range, 0-43,400). Left subclavian vein was more commonly used (57.7%). The success rate of GCE was 93.4% (406 of 435 procedures, 95% confidence interval: 91.0-97.5%). A total of 33 (7.5%) postoperative complications occurred including central line associated bloodstream infection (CLABSI) (n = 20, 4.5%), catheter dislodgement (n = 6, 1.4%), and catheter malfunction (n = 7, 1.6%). We conclude that GCE in pediatric cancer patients is associated with a high success rate and a low risk of complications. The most common postoperative complication, CLABSI, occurred at a rate significantly lower than following de novo CVC placement. © 2016 Wiley Periodicals, Inc.

Rectus sheath catheters for continuous analgesia after upper abdominal surgery.

PubMed

Cornish, Philip; Deacon, Alf

2007-01-01

The segmental nerves T6-T11 pass through and innervate the rectus abdominis muscle and overlying skin. The arcuate lines compartmentalize the rectus, but they are deficient posteriorly and hence a catheter tunnelled into the posterior sheath can be used to achieve an effective continuous analgesic block. Volume is important to fill the compartment. It is a simple surgical procedure that has several advantages and appears a viable alternative to epidural analgesia.

Development of an Infection-Responsive Fluorescent Sensor for the Early Detection of Urinary Catheter Blockage.

PubMed

Milo, Scarlet; Acosta, Florianne B; Hathaway, Hollie J; Wallace, Laura A; Thet, Naing T; Jenkins, A Toby A

2018-03-23

Formation of crystalline biofilms following infection by Proteus mirabilis can lead to encrustation and blockage of long-term indwelling catheters, with serious clinical consequences. We describe a simple sensor, placed within the catheter drainage bag, to alert of impending blockage via a urinary color change. The pH-responsive sensor is a dual-layered polymeric "lozenge", able to release the self-quenching dye 5(6)-carboxyfluorescein in response to the alkaline urine generated by the expression of bacterial urease. Sensor performance was evaluated within a laboratory model of the catheterized urinary tract, infected with both urease positive and negative bacterial strains under conditions of established infection, achieving an average "early warning" of catheter blockage of 14.5 h. Signaling only occurred following infection with urease positive bacteria. Translation of these sensors into a clinical environment would allow appropriate intervention before the occurrence of catheter blockage, a problem for which there is currently no effective control method.

Bacteriophage Can Prevent Encrustation and Blockage of Urinary Catheters by Proteus mirabilis

PubMed Central

Nzakizwanayo, Jonathan; Hanin, Aurélie; Alves, Diana R.; McCutcheon, Benjamin; Dedi, Cinzia; Salvage, Jonathan; Knox, Karen; Stewart, Bruce; Metcalfe, Anthony; Clark, Jason; Gilmore, Brendan F.; Gahan, Cormac G. M.; Jenkins, A. Toby A.

2015-01-01

Proteus mirabilis forms dense crystalline biofilms on catheter surfaces that occlude urine flow, leading to serious clinical complications in long-term catheterized patients, but there are presently no truly effective approaches to control catheter blockage by this organism. This study evaluated the potential for bacteriophage therapy to control P. mirabilis infection and prevent catheter blockage. Representative in vitro models of the catheterized urinary tract, simulating a complete closed drainage system as used in clinical practice, were employed to evaluate the performance of phage therapy in preventing blockage. Models mimicking either an established infection or early colonization of the catheterized urinary tract were treated with a single dose of a 3-phage cocktail, and the impact on time taken for catheters to block, as well as levels of crystalline biofilm formation, was measured. In models of established infection, phage treatment significantly increased time taken for catheters to block (∼3-fold) compared to untreated controls. However, in models simulating early-stage infection, phage treatment eradicated P. mirabilis and prevented blockage entirely. Analysis of catheters from models of established infection 10 h after phage application demonstrated that phage significantly reduced crystalline biofilm formation but did not significantly reduce the level of planktonic cells in the residual bladder urine. Taken together, these results show that bacteriophage constitute a promising strategy for the prevention of catheter blockage but that methods to deliver phage in sufficient numbers and within a key therapeutic window (early infection) will also be important to the successful application of phage to this problem. PMID:26711744

Urinary catheters

MedlinePlus

... drainage bag. The condom catheter must be changed every day. INTERMITTENT CATHETERS You would use an intermittent catheter ... and the catheter itself with soap and water every day. Also clean the area after every bowel movement ...

Assessment of right liver graft perfusion effectiveness between one and two-catheter infusion methods.

PubMed

Jung, Bo-Hyun; Hwang, Shin; Ha, Tae-Yong; Song, Gi-Won; Jung, Dong-Hwan; Kim, Ki-Hun; Ahn, Chul-Soo; Moon, Deok-Bog; Park, Gil-Chun; Kang, Sung-Hwa; Yoon, Young-In; Lee, Sung-Gyu

2014-05-01

Conventional graft perfusion method using one small-caliber catheter takes a relatively long time for right liver graft perfusion, thus some modification is needed. In this study, we intended to assess the effectiveness of right liver graft perfusion methods through comparison of different infusion catheters. The study consisted of two parts including one bench experiment to obtain data of hydraulic infusion and one clinical trial of 40 cases on graft perfusion with one- versus two-catheter infusion methods. These two graft infusion methods were compared in terms of the perfusion time and washing-out efficiency. At bench experiment, the infusion flow rate and infusion pressure were 3.3 ml/sec and 1.9 cmH20 in one blood transfusion catheter group, and 11.7 ml/sec and 3.1 cmH20 in single transurethral resection of prostate irrigation catheter group, and 6.6 ml/sec and 2.0 cmH20 in two blood transfusion catheters group, respectively. In clinical trial with 40 right liver grafts, two-catheter group had a shorter graft portal perfusion time for the first 2 L of histidine-tryptophan-ketoglutarate (HTK) solution than the conventional one-catheter group (375±25 seconds vs. 662±34 seconds; p=0.001) and a lower rate of incomplete blood washing-out after the initial 2 L portal perfusion (40% vs. 85%; p=0.03). The two-catheter infusion method appears to be more effective than the conventional one-catheter infusion method for right liver graft perfusion at the back table. Large size of right liver grafts seems to be its good indication.

Quantum tunneling recombination in a system of randomly distributed trapped electrons and positive ions.

PubMed

Pagonis, Vasilis; Kulp, Christopher; Chaney, Charity-Grace; Tachiya, M

2017-09-13

During the past 10 years, quantum tunneling has been established as one of the dominant mechanisms for recombination in random distributions of electrons and positive ions, and in many dosimetric materials. Specifically quantum tunneling has been shown to be closely associated with two important effects in luminescence materials, namely long term afterglow luminescence and anomalous fading. Two of the common assumptions of quantum tunneling models based on random distributions of electrons and positive ions are: (a) An electron tunnels from a donor to the nearest acceptor, and (b) the concentration of electrons is much lower than that of positive ions at all times during the tunneling process. This paper presents theoretical studies for arbitrary relative concentrations of electrons and positive ions in the solid. Two new differential equations are derived which describe the loss of charge in the solid by tunneling, and they are solved analytically. The analytical solution compares well with the results of Monte Carlo simulations carried out in a random distribution of electrons and positive ions. Possible experimental implications of the model are discussed for tunneling phenomena in long term afterglow signals, and also for anomalous fading studies in feldspars and apatite samples.

Heart rate variability during hemodialysis is an indicator for long-term vascular access survival in uremic patients

PubMed Central

Huang, Ya-Ting; Chang, Yu-Ming; Chen, I-Ling; Yang, Chuan-Lan; Leu, Show-Chin; Su, Hung-Li; Kao, Jsun-Liang; Tsai, Shih-Ching; Jhen, Rong-Na; Tang, Woung-Ru

2017-01-01

Background Vascular access (VA) is the lifeline of hemodialysis patients. Although the autonomic nervous system might be associated with VA failure (VAF), it has never been addressed in previous studies. This study aimed to evaluate the predictive values of the heart rate variability (HRV) indices for long-term VA outcomes. Methods This retrospective study was conducted using a prospectively established cohort enrolling 175 adult chronic hemodialysis patients (100 women, mean age 65.1 ± 12.9 years) from June 2010 to August 2010. Each participant received a series of HRV measurements at enrollment. After a 60-month follow-up period, we retrospectively reviewed all events and therapeutic procedures of the VAs which existed at the enrollment and during the follow-up period. Results During the 60-month follow-up period, 37 (26.8%) had VAF but 138 (73.2%) didn’t. The values of most HRV indices were statistically increased during hemodialysis since initiation in the non-VAF group, but not in the VAF group. Among all participants, the independent indicators for VAF included higher normalized high-frequency (nHF) activity [hazard ratio (HR) 1.04, p = 0.005], lower low-frequency/high-frequency (LF/HF) ratio (HR 0.80, p = 0.015), experience of urokinase therapy (HR 11.18, p = 0.002), percutaneous transluminal angioplasty (HR 2.88, p = 0.003) and surgical thrombectomy (HR 2.36, p = 0.035), as well as higher baseline serum creatinine (HR 1.07, p = 0.027) and potassium level (HR 1.58, p = 0.037). In subgroup analysis, a lower sympathetic activity indicated by lower LF/HF ratio was an independent indicator for VAF (HR 0.61, p = 0.03) for tunneled cuffed catheter, but conversely played a protective role against VAF (HR 1.27, p = 0.002) for arteriovenous fistula. Conclusions HRV is a useful tool for predicting long-term VAF among hemodialysis patients. PMID:28249028

A prospective randomized study of prophylactic teicoplanin to prevent early Hickman catheter-related sepsis in patients receiving intensive chemotherapy for haematological malignancies.

PubMed

Lim, S H; Smith, M P; Machin, S J; Goldstone, A H

1993-01-01

In all, 88 patients with haematological malignancies requiring Hickman catheters for intensive chemotherapy were randomized to receive either one single bolus intravenous injection of teicoplanin, 400 mg, or no teicoplanin immediately before insertion of a double-lumen Hickman catheter. Lower incidences of catheter-related Gram-positive sepsis were recorded in patients receiving prophylactic teicoplanin; exit site infection, tunnel infection and catheter-related Gram-positive septicaemia were all reduced. The benefit of prophylactic teicoplanin was observed particularly among patients who were already neutropenic at the time of catheterization. All Gram-positive organisms isolated from infected skin sites or from blood cultures taken from Hickman catheters were susceptible to teicoplanin. No adverse reaction was reported in any of the patients receiving prophylaxis. Prophylactic teicoplanin, therefore, may be used routinely for patients requiring insertion of Hickman catheters for intensive chemotherapy, to reduce the early incidence of catheter-related sepsis, particularly during the period of neutropenia following chemotherapy.

A prospective randomized study of prophylactic teicoplanin to prevent early Hickman catheter-related sepsis in patients receiving intensive chemotherapy for haematological malignancies.

PubMed

Lim, S H; Smith, M P; Salooja, N; Machin, S J; Goldstone, A H

1991-07-01

Eighty-eight patients with haematological malignancies requiring Hickman catheters for intensive chemotherapy were randomized to receive either one single bolus intravenous injection of teicoplanin or no teicoplanin immediately before insertion of a double lumen Hickman catheter. There were lower incidences of catheter-related Gram-positive sepsis in patients receiving prophylactic teicoplanin. There were less exit site infections, tunnel infections and catheter-related Gram-positive septicaemia. The benefit of prophylactic teicoplanin was observed especially among patients who were already neutropenic at the time of catheterization. All Gram-positive organisms isolated from the infected skin sites or from blood cultures taken from the Hickman catheters were sensitive to teicoplanin. No adverse reaction was reported in any of the patients in the prophylactic group. Prophylactic teicoplanin therefore may be used routinely for patients requiring insertion of Hickman catheters for intensive chemotherapy to reduce the early incidence of catheter-related sepsis, especially during the associated period of neutropenia following chemotherapy.

Blocked urinary catheters: solutions are not the only solution.

PubMed

Williams, Cath; Tonkin, Sharon

2003-07-01

The use of catheter maintenance solutions to manage clients whose catheters block has long been a subject for debate. An understanding of the causes of blockage, and awareness of appropriate management may reduce frequency of blockage and reduce unnecessary interruptions to a closed urinary drainage system.

Observations on the development of the crystalline bacterial biofilms that encrust and block Foley catheters.

PubMed

Stickler, D J; Morgan, S D

2008-08-01

The care of many patients undergoing long-term bladder catheterisation is complicated when the flow of urine through the catheter is blocked by encrustation. The problem results from infection by urease-producing bacteria, especially Proteus mirabilis, and the subsequent formation of crystalline biofilms on the catheter. The aim of this study was to discover how P. mirabilis initiates the development of these crystalline biofilms. The early stages in the formation of the biofilms were observed on a range of Foley catheters in a laboratory model of the catheterised bladder. Scanning electron micrographs revealed that when all-silicone, silicone-coated latex, hydrogel-coated latex, hydrogel/silver-coated latex and nitrofurazone silicone catheters were inserted into bladder models containing P. mirabilis and alkaline urine, their surfaces were rapidly coated with a microcrystalline foundation layer. X-ray microanalysis showed that this material was composed of calcium phosphate. Bacterial colonisation of the foundation layer followed and by 18h the catheters were encrusted by densely populated crystalline P. mirabilis biofilms. These observations have important implications for the development of encrustation-resistant catheters. In the case of silver catheters for example, bacterial cells can attach to the crystalline foundation layer and continue to grow, protected from contact with the underlying silver. If antimicrobials are to be incorporated into catheters to prevent encrustation, it is important that they diffuse into the urine and prevent the rise in pH that triggers crystal formation.

Fiber photo-catheters for laser treatment of atrial fibrillation

PubMed Central

Peshko, Igor; Rubtsov, Vladimir; Vesselov, Leonid; Sigal, Gennady; Laks, Hillel

2009-01-01

A fiber photo-catheter has been developed for surgical treatment of atrial fibrillation with laser radiation. Atrial fibrillation (AF) is a heart rhythm abnormality that involves irregular and rapid heartbeats. Recent studies demonstrate the superiority of treating AF disease with optical radiation of the near infrared region. To produce long continuous transmural lesions, solid-state lasers and laser diodes, along with end-emitting fiber catheters, have been used experimentally. The absence of side-emitting flexible catheters with the ability to produce long continuous lesions limits the further development of this technology. In this research, a prototype of an optical catheter, consisting of a flexible 10-cm fiber diffuser has been used to make continuous photocoagulation lesions for effective maze procedure treatments. The system also includes: a flexible optical reflector; a series of openings for rapid self-attachment to the tissue; and an optional closed-loop irrigating chamber with circulating saline to cool the optical diffuser and irrigate the tissue. PMID:19587838

A Novel Nonantibiotic Nitroglycerin-Based Catheter Lock Solution for Prevention of Intraluminal Central Venous Catheter Infections in Cancer Patients

PubMed Central

Hachem, Ray; Szvalb, Ariel; Taremi, Mahnaz; Granwehr, Bruno; Viola, George Michael; Sapna, Amin; Assaf, Andrew; Numan, Yazan; Shah, Pankil; Gasitashvili, Ketevan; Natividad, Elizabeth; Jiang, Ying; Slack, Rebecca; Reitzel, Ruth; Rosenblatt, Joel; Mouhayar, Elie; Raad, Issam

2017-01-01

ABSTRACT For long-term central lines (CL), the lumen is the major source of central line-associated bloodstream infections (CLABSI). The current standard of care for maintaining catheter patency includes flushing the CL with saline or heparin. Neither agent has any antimicrobial activity. Furthermore, heparin may enhance staphylococcal biofilm formation. We evaluated the safety and efficacy of a novel nonantibiotic catheter lock solution for the prevention of CLABSI. Between November 2015 and February 2016, we enrolled 60 patients with hematologic malignancies who had peripherally inserted central catheters (PICC) to receive the study lock solution. The study lock consisted of 15 or 30 μg/ml of nitroglycerin in combination with 4% sodium citrate and 22% ethanol. Each lumen was locked for at least 2 h once daily prior to being flushed. After enrollment of 10 patients at the lower nitroglycerin dose without evidence of toxicity, the dose was escalated to the higher dose (30 μg/ml). There were no serious related adverse events or episodes of hypotension with lock administration. Two patients experienced mild transient adverse events (one headache and one rash) possibly related to the lock and that resolved without residual effect. The CLABSI rate was 0 on lock days versus 1.6/1,000 catheter days (CD) off lock prophylaxis, compared with a rate of 1.9/1,000 CD at the institution in the same patient population. In conclusion, the nitroglycerin-based lock prophylaxis is safe and well tolerated. It may prevent CLABSI when given daily to cancer patients. Large, prospective, randomized clinical trials are needed to validate these findings. (This study has been registered at ClinicalTrials.gov under identifier NCT02577718.) PMID:28416559

An Intelligent Catheter System Robotic Controlled Catheter System

PubMed Central

Negoro, M.; Tanimoto, M.; Arai, F.; Fukuda, T.; Fukasaku, K.; Takahashi, I.; Miyachi, S.

2001-01-01

Summary We have developed a novel catheter system, an intelligent catheter system, which is able to control a catheter by an externally-placed controller. This system has made from master-slave mechanism and has following three components; 1) a joy stick as a master (for operators) 2)a catheter controller as a slave (for a patient),3)a micro force sensor as a sensing device. This catheter tele-guiding system has abilities to perform intravascular procedures from the distant places. It may help to reduce the radiation exposures to the operators and also to help train young doctors. PMID:20663387

An in-situ infection detection sensor coating for urinary catheters

PubMed Central

Milo, Scarlet; Thet, Naing Tun; Liu, Dan; Nzakizwanayo, Jonathan; Jones, Brian V.; Jenkins, A. Toby A.

2016-01-01

We describe a novel infection-responsive coating for urinary catheters that provides a clear visual early warning of Proteus mirabilis infection and subsequent blockage. The crystalline biofilms of P. mirabilis can cause serious complications for patients undergoing long-term bladder catheterisation. Healthy urine is around pH 6, bacterial urease increases urine pH leading to the precipitation of calcium and magnesium deposits from the urine, resulting in dense crystalline biofilms on the catheter surface that blocks urine flow. The coating is a dual layered system in which the lower poly(vinyl alcohol) layer contains the self-quenching dye carboxyfluorescein. This is capped by an upper layer of the pH responsive polymer poly(methyl methacrylate-co-methacrylic acid) (Eudragit S100®). Elevation of urinary pH (>pH 7) dissolves the Eudragit layer, releasing the dye to provide a clear visual warning of impending blockage. Evaluation of prototype coatings using a clinically relevant in vitro bladder model system demonstrated that coatings provide up to 12 h advanced warning of blockage, and are stable both in the absence of infection, and in the presence of species that do not cause catheter blockage. At the present time, there are no effective methods to control these infections or provide warning of impending catheter blockage. PMID:26945183

An in-situ infection detection sensor coating for urinary catheters.

PubMed

Milo, Scarlet; Thet, Naing Tun; Liu, Dan; Nzakizwanayo, Jonathan; Jones, Brian V; Jenkins, A Toby A

2016-07-15

We describe a novel infection-responsive coating for urinary catheters that provides a clear visual early warning of Proteus mirabilis infection and subsequent blockage. The crystalline biofilms of P. mirabilis can cause serious complications for patients undergoing long-term bladder catheterisation. Healthy urine is around pH 6, bacterial urease increases urine pH leading to the precipitation of calcium and magnesium deposits from the urine, resulting in dense crystalline biofilms on the catheter surface that blocks urine flow. The coating is a dual layered system in which the lower poly(vinyl alcohol) layer contains the self-quenching dye carboxyfluorescein. This is capped by an upper layer of the pH responsive polymer poly(methyl methacrylate-co-methacrylic acid) (Eudragit S100®). Elevation of urinary pH (>pH 7) dissolves the Eudragit layer, releasing the dye to provide a clear visual warning of impending blockage. Evaluation of prototype coatings using a clinically relevant in vitro bladder model system demonstrated that coatings provide up to 12h advanced warning of blockage, and are stable both in the absence of infection, and in the presence of species that do not cause catheter blockage. At the present time, there are no effective methods to control these infections or provide warning of impending catheter blockage. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Design of a pulse-type strain gauge balance for a long-test-duration hypersonic shock tunnel

NASA Astrophysics Data System (ADS)

Wang, Y.; Liu, Y.; Jiang, Z.

2016-11-01

When the measurement of aerodynamic forces is conducted in a hypersonic shock tunnel, the inertial forces lead to low-frequency vibrations of the model, and its motion cannot be addressed through digital filtering because a sufficient number of cycles cannot be obtained during a tunnel run. This finding implies restrictions on the model size and mass as the natural frequencies are inversely proportional to the length scale of the model. Therefore, the force measurement still has many problems, particularly for large and heavy models. Different structures of a strain gauge balance (SGB) are proposed and designed, and the measurement element is further optimized to overcome the difficulties encountered during the measurement of aerodynamic forces in a shock tunnel. The motivation for this study is to assess the structural performance of the SGB used in a long-test-duration JF12 hypersonic shock tunnel, which has more than 100 ms of test time. Force tests were conducted for a large-scale cone with a 10^° semivertex angle and a length of 0.75 m in the JF12 long-test-duration shock tunnel. The finite element method was used for the analysis of the vibrational characteristics of the Model-Balance-Sting System (MBSS) to ensure a sufficient number of cycles, particularly for the axial force signal during a shock tunnel run. The higher-stiffness SGB used in the test shows good performance, wherein the frequency of the MBSS increases because of the stiff construction of the balance. The experimental results are compared with the data obtained in another wind tunnel and exhibit good agreement at M = 7 and α =5°.

Development and psychometric properties of a measure of catheter burden with bladder drainage after pelvic reconstructive surgery.

PubMed

Carpenter, Janet S; Heit, Michael; Rand, Kevin L

2017-04-01

Catheter burden after pelvic reconstructive surgery is an important patient-reported quality of life outcome in research and clinical practice. However, existing tools focus on long-term catheter users rather than short-term postoperative patients. The study aim was to evaluate the psychometric properties of a modified version of the intermittent self-catheterization questionnaire (ISC-Q) in postoperative pelvic reconstructive patients. After experts convened to discuss and modify the ISC-Q items based on their knowledge of women's experiences and clinical practices, 178 women (108 with transurethral and 70 with suprapubic catheters) completed the modified scale and other measures as part of a larger parent study designed to assess health-related quality of life (HRQoL) following pelvic reconstructive surgery requiring bladder drainage. During psychometric testing, the modified ISC-Q was reduced to six items encompassing two factors: a three-item difficulty of use factor and a 3-item embarrassment factor. The new scale was named the short-term catheter burden questionnaire (STCBQ). The two-factor model was robust in both subsamples. Only scores within and not between subsamples can be meaningfully compared due to a lack of scalar invariance. Correlations among STCBQ total scores, subscores, and a single satisfaction item indicated good construct validity. Correlations with patient demographics provided further information about the scale. The STCBQ is a short, efficient assessment of short-term catheter burden following pelvic reconstructive surgery. The scale can be used as an important patient reported outcome measure in clinical practice and research. Neurourol. Urodynam. 36:1140-1146, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Analysis of wind-tunnel stability and control tests in terms of flying qualities of full-scale airplanes

NASA Technical Reports Server (NTRS)

Kayten, Gerald G

1945-01-01

The analysis of results of wind-tunnel stability and control tests of powered airplane models in terms of the flying qualities of full-scale airplanes is advocated. In order to indicated the topics upon which comments are considered desirable in the report of a wind-tunnel stability and control investigation and to demonstrate the nature of the suggested analysis, the present NACA flying-qualities requirements are discussed in relation to wind-tunnel tests. General procedures for the estimation of flying qualities from wind-tunnel tests are outlined.

Permanent catheters for recurrent ascites-a critical and systematic review of study methodology.

PubMed

Christensen, Lars; Wildgaard, Lorna; Wildgaard, Kim

2016-06-01

Management of refractory ascites traditionally includes medical treatment with diuretics or intermittent paracentesis. Patients with recurrent ascites may benefit from the use of permanent intra-abdominal catheters with more frequent drainage without hospitalization. The objective was to systematically asses the methodology of factors and endpoints reported in studies investigating permanent catheters for recurrent ascites treatment. Using a systematic search strategy, we critically assessed the methodology when treating refractory ascites using a permanent catheter. Studies critically assessed included both retro- and prospective studies. A total of 715 unique articles were found via PubMed, The Cochrane Library and Embase. Twenty-nine studies (tunnelled catheter = 12, peritoneal ports = 6 and peritoneovenous shunts = 11) with three distinct types of permanent catheters fulfilled the inclusion criteria. Only three studies reported technical success less than 100 %. Data on complications and treatment were not available in all papers; peritonitis (48 %), cellulitis (41 %), prophylactic antibiotics (48 %) and complications to catheter insertion were difficult to distinguish from advanced co-morbidity of patients. Thirteen studies (45 %) reported some type of evaluating patient experience or functional outcome, but only three studies used validated reproducible scales when assessing outcomes. Fifteen of the 29 studies included 30 patients or less. Knowledge is limited because complications and outcomes are poorly defined. The expected increase in catheter treatment of refractory ascites necessitates comparative studies, using validated patient-related outcomes, and the reporting of unambiguous complications. A proposal of variables to include in future studies is presented.

Post-marketing surveillance in the published medical and grey literature for percutaneous transluminal coronary angioplasty catheters: a systematic review.

PubMed

Polisena, Julie; Forster, Alan J; Cimon, Karen; Rabb, Danielle

2013-10-10

Post-marketing surveillance (PMS) may identify rare serious incidents or adverse events due to the long-term use of a medical device, which was not captured in the pre-market process. Percutaneous transluminal coronary angioplasty (PTCA) is a non-surgical procedure that uses a balloon-tipped catheter to enlarge a narrowed artery. In 2011, 1,942 adverse event reports related to the use of PTCA catheters were submitted to the FDA by the manufacturers, an increase from the 883 reported in 2008. The primary research objective is to conduct a systematic review of the published and grey literature published between 2007 and 2012 for the frequency of incidents, adverse events and malfunctions associated with the use of PTCA catheters in patients with coronary artery disease (CAD). Grey literature has not been commercially published. We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials and PubMed for medical literature on PMS for PTCA catheters in patients with CAD published between January 2007 and July 2012. We also searched the grey literature. This review included 11 studies. The in-hospital adverse events reported were individual cases of myocardial infarction and hematoma. In studies of patients with coronary perforation, more patients with balloon angioplasty were identified compared with patients who required stenting. Our systematic review illustrates that the volume and quality of PMS studies associated with the use of PTCA catheters in patients with CAD are low in the published and grey literature, and may not be useful sources of information for decisions on safety. In most studies, the objectives were not to monitor the long-term safety of the use of PTCA catheters in clinical practice. Future studies can explore the strengths and limitations of PMS databases administered by regulatory authorities.

Long‐term Outcomes of Catheter Ablation of Atrial Fibrillation: A Systematic Review and Meta‐analysis

PubMed Central

Ganesan, Anand N.; Shipp, Nicholas J.; Brooks, Anthony G.; Kuklik, Pawel; Lau, Dennis H.; Lim, Han S.; Sullivan, Thomas; Roberts‐Thomson, Kurt C.; Sanders, Prashanthan

2013-01-01

Background In the past decade, catheter ablation has become an established therapy for symptomatic atrial fibrillation (AF). Until very recently, few data have been available to guide the clinical community on the outcomes of AF ablation at ≥3 years of follow‐up. We aimed to systematically review the medical literature to evaluate the long‐term outcomes of AF ablation. Methods and Results A structured electronic database search (PubMed, Embase, Web of Science, Cochrane) of the scientific literature was performed for studies describing outcomes at ≥3 years after AF ablation, with a mean follow‐up of ≥24 months after the index procedure. The following data were extracted: (1) single‐procedure success, (2) multiple‐procedure success, and (3) requirement for repeat procedures. Data were extracted from 19 studies, including 6167 patients undergoing AF ablation. Single‐procedure freedom from atrial arrhythmia at long‐term follow‐up was 53.1% (95% CI 46.2% to 60.0%) overall, 54.1% (95% CI 44.4% to 63.4%) in paroxysmal AF, and 41.8% (95% CI 25.2% to 60.5%) in nonparoxysmal AF. Substantial heterogeneity (I2>50%) was noted for single‐procedure outcomes. With multiple procedures, the long‐term success rate was 79.8% (95% CI 75.0% to 83.8%) overall, with significant heterogeneity (I2>50%).The average number of procedures per patient was 1.51 (95% CI 1.36 to 1.67). Conclusions Catheter ablation is an effective and durable long‐term therapeutic strategy for some AF patients. Although significant heterogeneity is seen with single procedures, long‐term freedom from atrial arrhythmia can be achieved in some patients, but multiple procedures may be required. PMID:23537812

Differences in Bacterial Colonization and Biofilm Formation Property of Uropathogens between the Two most Commonly used Indwelling Urinary Catheters.

PubMed

Verma, Amit; Bhani, Deepa; Tomar, Vinay; Bachhiwal, Rekha; Yadav, Shersingh

2016-06-01

Catheter Associated Urinary Tract Infections (CAUTI) are one of the most common cause of nosocomial infections. Many bacterial species show biofilm production, which provides survival benefit to them by providing protection from environmental stresses and causing decreased susceptibility to antimicrobial agents. Two most common types of catheters used in our setup are pure silicone catheter and silicone coated latex catheter. The advantage of pure silicone catheter for long term catheterization is well established. But there is still a controversy about any advantage of the silicone catheter regarding bacterial colonization rates and their biofilm production property. The aim of our study was to compare the bacterial colonization and the biofilm formation property of the colonizing bacteria in patients with indwelling pure silicone and silicone coated latex catheters. This prospective observational study was conducted in the Urology Department of our institute. Patients who needed catheterization for more than 5 days during the period July 2015 to January 2016 and had sterile precatheterisation urine were included in the study. Patients were grouped into 2 groups of 50 patients each, Group A with the pure silicone catheter and Group B with the silicone coated latex catheter. Urine culture was done on the 6(th) day of indwelling urinary catheter drainage. If growth was detected, then that bacterium was tested for biofilm production property by tissue culture plate method. Statistical analyses were performed using the Statistical Package for the Social Science Version 22 (SPSS-22). After 5 days of indwelling catheterization, the pure silicone catheter had significantly less bacterial colonization than the silicone coated latex catheter (p-value=0.03) and the biofilm forming property of colonizing bacteria was also significantly less in the pure silicone catheter as compared to the silicone coated latex catheter (p-value=0.02). There were no significant differences in

Design and calibration of the carousel wind tunnel

NASA Technical Reports Server (NTRS)

Leach, R. N.; Greeley, R.; Iversen, J.; White, B.; Marshall, J. R.

1986-01-01

In the study of planetary aeolian processes the effect of gravity is not readily modeled. Gravity appears in the equations of particle motion along with interparticle forces but the two terms are not separable. A wind tunnel that would permit variable gravity would allow separation of the forces and aid greatly in understanding planetary aeolian processes. The design Carousel Wind Tunnel (CWT) allows for a long flow distance in a small sized tunnel since the test section is a continuo us circuit and allows for a variable pseudo gravity. A prototype design was built and calibrated to gain some understanding of the characteristics of the design and the results presented.

Design and calibration of the carousel wind tunnel

NASA Technical Reports Server (NTRS)

Leach, R. N.; Greeley, Ronald; Iversen, James D.; White, Bruce R.; Marshall, John R.

1987-01-01

In the study of planetary aeolian processes the effect of gravity is not readily modeled. Gravity appears in the equations of particle motion along with interparticle forces but the two terms are not separable. A wind tunnel that would permit variable gravity would allow separation of the forces and aid greatly in understanding planetary aeolian processes. The design of the Carousel Wind Tunnel (CWT) allows for a long flow distance in a small sized tunnel since the test section is a continuous circuit and allows for a variable pseudo-gravity. A prototype design was built and calibrated to gain some understanding of the characteristics of the design and the results presented.

Note: long-range scanning tunneling microscope for the study of nanostructures on insulating substrates.

PubMed

Molina-Mendoza, Aday J; Rodrigo, José G; Island, Joshua; Burzuri, Enrique; Rubio-Bollinger, Gabino; van der Zant, Herre S J; Agraït, Nicolás

2014-02-01

The scanning tunneling microscope (STM) is a powerful tool for studying the electronic properties at the atomic level, however, it is of relatively small scanning range and the fact that it can only operate on conducting samples prevents its application to study heterogeneous samples consisting of conducting and insulating regions. Here we present a long-range scanning tunneling microscope capable of detecting conducting micro and nanostructures on insulating substrates using a technique based on the capacitance between the tip and the sample and performing STM studies.

[Suprapubic urinary diversion using Cystofix--an alternative to the urethral indwelling catheter].

PubMed

Müller, J; Sulmoni, M

1992-01-01

Suprapubic Cystofix-cystostomy is a valuable alternative to the Foley-catheter. The advantages of suprapubic cystostomy are mainly a reduction of urinary tract infections, inflammatory reactions in the lower urinary tract and avoidance of late urethral strictures after transurethral catheterism. There are a few contraindications to be considered, mainly an empty bladder and coagulation disorders. The complication rate of suprapubic Cystofix-cystostomy, usually gross haematuria, is very low. Cystofix-cystostomy is as useful for short term urinary drainage as for long term drainage in the case of chronic voiding disorders.

[Laparoscopic management of ureteroileal stenosis: Long term follow up.

PubMed

Emiliani, Esteban; Gavrilov, Pavel; Mayordomo, Olga; Salvador, Josep; Palou, Joan; Rosales, Antonio; Villavicencio, Humberto

2017-05-01

To describe the laparoscopic approach for uretero-ileal anastomosis strictures and to analyse our long term series. A retrospective review was performed evaluating our series of patients with benign ureteroileal anastomosis strictures treated laparoscopically from 2011 to 2017. Demographics and perioperative data were obtained and analyzed. Complications were described with the Clavien-Dindo classification. The surgical technique was described and a literature review was performed. Eleven procedures were performed in ten patients. Mean blood loss was 180 ml. All the operations were performed laparoscopically without conversion. Mean hospital stay was 10 days (4-23). Early complications were Clavien-Dindo I y II: Two cases of limited anastomosis leakage, one lymphorrea, one paralitic ileum and one accidental descent of the ureteral catheter. Mean follow-up was 56 months (12-179) No late complications have been described. Based on our series with 5 year follow up, the laparoscopic approach for uretero-ileal anastomosis strictures is feasible and safe.

Simulation-based medical education training improves short and long-term competency in, and knowledge of central venous catheter insertion: A before and after intervention study.

PubMed

Cartier, Vanessa; Inan, Cigdem; Zingg, Walter; Delhumeau, Cecile; Walder, Bernard; Savoldelli, Georges L

2016-08-01

Multimodal educational interventions have been shown to improve short-term competency in, and knowledge of central venous catheter (CVC) insertion. To evaluate the effectiveness of simulation-based medical education training in improving short and long-term competency in, and knowledge of CVC insertion. Before and after intervention study. University Geneva Hospital, Geneva, Switzerland, between May 2008 and January 2012. Residents in anaesthesiology aware of the Seldinger technique for vascular puncture. Participants attended a half-day course on CVC insertion. Learning objectives included work organization, aseptic technique and prevention of CVC complications. CVC insertion competency was tested pretraining, posttraining and then more than 2 years after training (sustainability phase). The primary study outcome was competency as measured by a global rating scale of technical skills, a hand hygiene compliance score and a checklist compliance score. Secondary outcome was knowledge as measured by a standardised pretraining and posttraining multiple-choice questionnaire. Statistical analyses were performed using paired Student's t test or Wilcoxon signed-rank test. Thirty-seven residents were included; 18 were tested in the sustainability phase (on average 34 months after training). The average global rating of skills was 23.4 points (±SD 4.08) before training, 32.2 (±4.51) after training (P < 0.001 for comparison with pretraining scores) and 26.5 (±5.34) in the sustainability phase (P = 0.040 for comparison with pretraining scores). The average hand hygiene compliance score was 2.8 (±1.0) points before training, 5.0 (±1.04) after training (P < 0.001 for comparison with pretraining scores) and 3.7 (±1.75) in the sustainability phase (P = 0.038 for comparison with pretraining scores). The average checklist compliance was 14.9 points (±2.3) before training, 19.9 (±1.06) after training (P < 0.001 for comparison with pretraining scores) and

Efficacy of long scleral tunnel technique in preventing Ahmed glaucoma valve tube exposure through conjunctiva.

PubMed

Kugu, Suleyman; Erdogan, Gurkan; Sevim, M Sahin; Ozerturk, Yusuf

2015-01-01

To evaluate the efficacy of long scleral tunnel technique used in Ahmed glaucoma valve (AGV) implantation in preventing tube exposure through conjunctiva. Patients of adult age, who were unresponsive to maximum medical treatment and underwent AGV implantation, were divided into two groups and investigated retrospectively. Group 1 consisted of 40 eyes of 38 patients that underwent surgery by long scleral tunnel technique and Group 2 consisted of 38 eyes of 35 patients that underwent implantation by processed pericardium patch graft method. The mean age was 54.8 ± 14.6 years (range 26-68 years) and the mean follow-up duration was 46.7 ± 19.4 months (range 18-76 months) for the patients in Group 1, whereas the mean age was 58.6 ± 16.7 years (range 32-74 years) and mean follow-up period was 43.6 ± 15.7 months (range 20-72 months) for the patients in Group 2 (p > 0.05). In the course of follow-up, tube exposure was detected in one (2.5%) eye in Group 1 and in three (7.9%) eyes in Group 2 (p = 0.042). Long scleral tunnel technique is beneficial in preventing conjunctival tube exposure in AGV implantation surgery.

Innovations in Balloon Catheter Technology in Rhinology.

PubMed

D'Anza, Brian; Sindwani, Raj; Woodard, Troy D

2017-06-01

Since being introduced more than 10 years ago, balloon catheter technology (BCT) has undergone several generations of innovations. From construction to utilization, there has been a myriad of advancements in balloon technology. The ergonomics of the balloon dilation systems have improved with a focus on limiting the extra assembly. "Hybrid" BCT procedures have shown promise in mucosal preservation, including treating isolated complex frontal disease. Multiple randomized clinical trials report improved long-term outcomes in stand-alone BCT, including in-office use. The ever-expanding technological innovations ensure BCT will be a key component in the armamentarium of the modern sinus surgeon. Copyright © 2017 Elsevier Inc. All rights reserved.

[Biodegradable catheters and urinary stents. When?

PubMed

Soria, F; Morcillo, E; López de Alda, A; Pastor, T; Sánchez-Margallo, F M

2016-10-01

One of the main wishes in the field of urinary catheters and stents is to arm them with biodegradable characteristics because we consider a failure of these devices the need for retrieval, the forgotten catheter syndrome as well as the adverse effects permanent devices cause after fulfilling their aim. The efforts focused in new designs, coatings and biomaterials aim to increase the biocompatibility of theses internal devices. Lately, there have been correct advances to answer the main challenges regarding biodegradable ureteral devices. Thus, modulation of the rate of degradation has been achieved thanks to new biomaterials and the use of copolymers that enable to choose the time of permanence as it is programmed with conventional double J catheters. Biocompatibility has improved with the use of new polymers that adapt better to the urine. Finally, one of the main problems is elimination of degraded fragments and experimentally it has be demonstrated that new designs elicit controlled degradation, from distal to proximal; using stranding and combination of copolymers degradation may be caused by dilution, reducing fragmentation to the last stages of life of the prosthesis. Moreover, it has been demonstrated that biodegradable catheters potentially may cause less urinary tract infection, less encrustation and predictably they will diminish catheter morbidity, since their degradation process reduces adverse effects. Regarding the development of biodegradable urethral stents, it is necessary to find biomaterials that enable maintaining their biomechanical properties in the long term, keeping open the urethral lumen both in patients with BPH and urethral stenosis. Modulation of the time of degradation of the prosthesis has been achieved, but the appearance of urothelial hyperplasia is still a constant in the initial phases after implantation. The development of drug eluting stents, anti-proliferative or anti-inflammatory, as well as biodegradable stents biocoated is a

Robotic positioning of standard electrophysiology catheters: a novel approach to catheter robotics.

PubMed

Knight, Bradley; Ayers, Gregory M; Cohen, Todd J

2008-05-01

Robotic systems have been developed to manipulate and position electrophysiology (EP) catheters remotely. One limitation of existing systems is their requirement for specialized catheters or sheaths. We evaluated a system (Catheter Robotics Remote Catheter Manipulation System [RCMS], Catheter Robotics, Inc., Budd Lake, New Jersey) that manipulates conventional EP catheters placed through standard introducer sheaths. The remote controller functions much like the EP catheter handle, and the system permits repeated catheter disengagement for manual manipulation without requiring removal of the catheter from the body. This study tested the hypothesis that the RCMS would be able to safely and effectively position catheters at various intracardiac sites and obtain thresholds and electrograms similar to those obtained with manual catheter manipulation. Two identical 7 Fr catheters (Blazer II; Boston Scientific Corp., Natick, Massachusetts) were inserted into the right femoral veins of 6 mongrel dogs through separate, standard 7 Fr sheaths. The first catheter was manually placed at a right ventricular endocardial site. The second catheter handle was placed in the mating holder of the RCMS and moved to approximately the same site as the first catheter using the Catheter Robotics RCMS. The pacing threshold was determined for each catheter. This sequence was performed at 2 right atrial and 2 right ventricular sites. The distance between the manually and robotically placed catheters tips was measured, and pacing thresholds and His-bundle recordings were compared. The heart was inspected at necropsy for signs of cardiac perforation or injury. Compared to manual positioning, remote catheter placement produced the same pacing threshold at 7/24 sites, a lower threshold at 11/24 sites, and a higher threshold at only 6/24 sites (p > 0.05). The average distance between catheter tips was 0.46 +/- 0.32 cm (median 0.32, range 0.13-1.16 cm). There was no difference between right atrial

Ethanol combined with heparin as a locking solution for the prevention of catheter related blood stream infections in hemodialysis patients: A prospective randomized study.

PubMed

Sofroniadou, Sofia; Revela, Ioanna; Kouloubinis, Alexandros; Makriniotou, Ioanna; Zerbala, Sinodi; Smirloglou, Despina; Kalocheretis, Petros; Drouzas, Apostolos; Samonis, George; Iatrou, Christos

2017-10-01

Ethanol lock solution has been mainly administered in paediatric and home parenteral nutrition patients in order to prevent catheter related blood stream infections (CRBSI). Its utility in hemodialysis (HD) patients with non-tunneled-uncuffed catheter (NTC) has been poorly explored. We conducted a prospective randomized study in chronic HD patients requiring a newly inserted NTC-while awaiting for the maturation of an already established arteriovenous fistula (AVF) or arteriovenous graft (AVG) or tunneled-cuffed catheter insertion. Patients were randomized in two groups: Group A, where the lock solution was ethanol 70% + unfractionated heparin 2000 U/mL and group B, that received only unfractionated heparin 2000 U/mL. Primary end point was CRBSIs whereas exit site infections, thrombotic and bleeding episodes were the secondary end points. One hundred three HD patients were enrolled in the study (group A, n = 52; group B, n = 51). The median number of catheter days was 32 for group A (range: 23-39) and 34 (range: 27-40) for group B with no statistically significant difference between the two groups. Group A (ethanol + heparin) demonstrated 4/52 episodes (7.69%) of CRBSI whereas Group B (heparin) 11/51 episodes (21.57%) (P = 0.04). CRBSI rates per 1000 catheter days were 2.53/1000 catheter days for group A and 6.7/1000 catheter days for group B (P = 0.04). Mean cumulative infection-free catheter survival in the ethanol group did not differ significantly compared to the heparin group (log-rank test = 2.99, P = 0.08). Thrombotic episodes did not differ between the two groups. Locking of NTCs in HD patients with ethanol 70% + unfractionated heparin reduces CRBSI rates without increasing the thrombotic episodes. © 2017 International Society for Hemodialysis.

Catheter-associated urinary tract infections and other infections in patients hospitalized for acute stroke: A prospective cohort study of two different silicone catheters.

PubMed

Stenzelius, Karin; Laszlo, Liselott; Madeja, Magdalena; Pessah-Rasmusson, Hélène; Grabe, Magnus

2016-12-01

Catheter-associated urinary tract infection (CAUTI) is the most common healthcare-associated infection. The primary aim of this study was to investigate whether the use of a silicone catheter coated with an ultrathin layer of a combination of the noble metals gold, palladium and silver (BIP™-silicone catheter) could reduce the incidence of CAUTI and antibiotic prescription compared with a standard silicone catheter in a cohort of acute neurological patients suffering primarily from stroke. At the same time, all infectious events requiring prescription of an antimicrobial agent were registered and are reported. The study was designed as a crossover cohort study enrolling men and women aged over 18 years, requiring emergency management for stroke including the insertion of an indwelling catheter. Data on patient characteristics, urinary tract infections (UTIs), other infectious events and all antibiotic prescriptions were recorded prospectively. The patients' characteristics differed in the two centres in terms of age but not in diagnosis distribution. UTIs were recorded in 78 (24.2%) of the patients, ahead of pulmonary tract infections (n = 65; 20.2%). There was no difference in terms of CAUTI in the two catheter groups, even in subgroups with catheter treatment for 1 week or less. The patients with a diagnosed UTI required 3.5 more days of hospitalization than those without a UTI. CAUTIs were the most frequent healthcare-associated infections, slightly ahead of pulmonary tract infections. No advantages of the coated catheter could be found in this cohort of critically ill patients.

Advanced Imaging Catheter: Final Project Report

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

Krulevitch, P; Colston, B; DaSilva, L

2001-07-20

Minimally invasive surgery (MIS) is an approach whereby procedures conventionally performed with large and potentially traumatic incisions are replaced by several tiny incisions through which specialized instruments are inserted. Early MIS, often called laparoscopic surgery, used video cameras and laparoscopes to visualize and control the medical devices, which were typically cutting or stapling tools. More recently, catheter-based procedures have become a fast growing sector of all surgeries. In these procedures, small incisions are made into one of the main arteries (e.g. femoral artery in the thigh), and a long thin hollow tube is inserted and positioned near the target area.more » The key advantage of this technique is that recovery time can be reduced from months to a matter of days. In the United States, over 700,000 catheter procedures are performed annually representing a market of over $350 million. Further growth in this area will require significant improvements in the current catheter technology. In order to effectively navigate a catheter through the tortuous vessels of the body, two capabilities must exist: imaging and positioning. In most cases, catheter procedures rely on radiography for visualization and manual manipulation for positioning of the device. Radiography provides two-dimensional, global images of the vasculature and cannot be used continuously due to radiation exposure to both the patient and physician. Intravascular ultrasound devices are available for continuous local imaging at the catheter tip, but these devices cannot be used simultaneously with therapeutic devices. Catheters are highly compliant devices, and manipulating the catheter is similar to pushing on a string. Often, a guide wire is used to help position the catheter, but this procedure has its own set of problems. Three characteristics are used to describe catheter maneuverability: (1) pushability -- the amount of linear displacement of the distal end (inside body

Catheter-based renal denervation for treatment of resistant hypertension

PubMed Central

Hatipoglu, Emine; Ferro, Albert

2013-01-01

Hypertension is a common disease associated with important cardiovascular complications. Persistent blood pressure of 140/90 or higher despite combined use of a reninangiotensin system blocker, calcium channel blocker and a diuretic at highest tolerated doses constitutes resistant hypertension. Excess sympathetic activity plays an important pathogenic role in resistant hypertension in addition to contributing to the development of metabolic problems, in particular diabetes. Reduction of renal sympathetic activity by percutaneous catheter-based radiofrequency ablation via the renal arteries has been shown in several studies to decrease blood pressure in patients with resistant hypertension, and importantly is largely free of significant complications. However, longer term follow-up is required to confirm both long-term safety and efficacy. PMID:24175081

Catheter tip force transducer for cardiovascular research

NASA Technical Reports Server (NTRS)

Feldstein, C.; Lewis, G. W.; Silver, R. H.; Culler, V. H. (Inventor)

1976-01-01

A force transducer for measuring dynamic force activity within the heart of a subject essentially consists of a U-shaped beam of low elastic compliance material. Two lines extend from the beams's legs and a long coil spring is attached to the beam. A strain gauge is coupled to one of the beam's legs to sense deflections thereof. The beam with the tines and most of the spring are surrounded by a flexible tube, defining a catheter, which is insertable into a subject's heart through an appropriate artery. The tines are extractable from the catheter for implantation into the myocardium by pushing on the end of the spring which extends beyond the external end of the catheter.

Ring and peg electrodes for minimally-Invasive and long-term sub-scalp EEG recordings.

PubMed

Benovitski, Y B; Lai, A; McGowan, C C; Burns, O; Maxim, V; Nayagam, D A X; Millard, R; Rathbone, G D; le Chevoir, M A; Williams, R A; Grayden, D B; May, C N; Murphy, M; D'Souza, W J; Cook, M J; Williams, C E

2017-09-01

Minimally-invasive approaches are needed for long-term reliable Electroencephalography (EEG) recordings to assist with epilepsy diagnosis, investigation and more naturalistic monitoring. This study compared three methods for long-term implantation of sub-scalp EEG electrodes. Three types of electrodes (disk, ring, and peg) were fabricated from biocompatible materials and implanted under the scalp in five ambulatory ewes for 3months. Disk electrodes were inserted into sub-pericranial pockets. Ring electrodes were tunneled under the scalp. Peg electrodes were inserted into the skull, close to the dura. EEG was continuously monitored wirelessly. High resolution CT imaging, histopathology, and impedance measurements were used to assess the status of the electrodes at the end of the study. EEG amplitude was larger in the peg compared with the disk and ring electrodes (p<0.05). Similarly, chewing artifacts were lower in the peg electrodes (p<0.05). Electrode impedance increased after long-term implantation particularly for those within the bone (p<0.01). Micro-CT scans indicated that all electrodes stayed within the sub-scalp layers. All pegs remained within the burr holes as implanted with no evidence of extrusion. Eight of 10 disks partially eroded into the bone by 1.0mm from the surface of the skull. The ring arrays remained within the sub-scalp layers close to implantation site. Histology revealed that the electrodes were encapsulated in a thin fibrous tissue adjacent to the pericranium. Overlying this was a loose connective layer and scalp. Erosion into the bone occurred under the rim of the sub-pericranial disk electrodes. The results indicate that the peg electrodes provided high quality EEG, mechanical stability, and lower chewing artifact. Whereas, ring electrode arrays tunneled under the scalp enable minimal surgical techniques to be used for implantation and removal. Copyright © 2017 Elsevier B.V. All rights reserved.

Catheter Ablation versus Thoracoscopic Surgical Ablation in Long Standing Persistent Atrial Fibrillation (CASA-AF): study protocol for a randomised controlled trial.

PubMed

Khan, Habib Rehman; Kralj-Hans, Ines; Haldar, Shouvik; Bahrami, Toufan; Clague, Jonathan; De Souza, Anthony; Francis, Darrel; Hussain, Wajid; Jarman, Julian; Jones, David Gareth; Mediratta, Neeraj; Mohiaddin, Raad; Salukhe, Tushar; Jones, Simon; Lord, Joanne; Murphy, Caroline; Kelly, Joanna; Markides, Vias; Gupta, Dhiraj; Wong, Tom

2018-02-20

Atrial fibrillation is the commonest arrhythmia which raises the risk of heart failure, thromboembolic stroke, morbidity and death. Pharmacological treatments of this condition are focused on heart rate control, rhythm control and reduction in risk of stroke. Selective ablation of cardiac tissues resulting in isolation of areas causing atrial fibrillation is another treatment strategy which can be delivered by two minimally invasive interventions: percutaneous catheter ablation and thoracoscopic surgical ablation. The main purpose of this trial is to compare the effectiveness and safety of these two interventions. Catheter Ablation versus Thoracoscopic Surgical Ablation in Long Standing Persistent Atrial Fibrillation (CASA-AF) is a prospective, multi-centre, randomised controlled trial within three NHS tertiary cardiovascular centres specialising in treatment of atrial fibrillation. Eligible adults (n = 120) with symptomatic, long-standing, persistent atrial fibrillation will be randomly allocated to either catheter ablation or thoracoscopic ablation in a 1:1 ratio. Pre-determined lesion sets will be delivered in each treatment arm with confirmation of appropriate conduction block. All patients will have an implantable loop recorder (ILR) inserted subcutaneously immediately following ablation to enable continuous heart rhythm monitoring for at least 12 months. The devices will be programmed to detect episodes of atrial fibrillation and atrial tachycardia ≥ 30 s in duration. The patients will be followed for 12 months, completing appropriate clinical assessments and questionnaires every 3 months. The ILR data will be wirelessly transmitted daily and evaluated every month for the duration of the follow-up. The primary endpoint in the study is freedom from atrial fibrillation and atrial tachycardia at the end of the follow-up period. The CASA-AF Trial is a National Institute for Health Research-funded study that will provide first-class evidence on the

Understanding long-term silver release from surface modified porous titanium implants.

PubMed

Shivaram, Anish; Bose, Susmita; Bandyopadhyay, Amit

2017-08-01

Prevention of orthopedic device related infection (ODRI) using antibiotics has met with limited amount of success and is still a big concern during post-surgery. As an alternative, use of silver as an antibiotic treatment to prevent surgical infections is being used due to the well-established antimicrobial properties of silver. However, in most cases silver is used in particulate form with wound dressings or with short-term devices such as catheters but not with load-bearing implants. We hypothesize that strongly adherent silver to load-bearing implants can offer longer term solution to infection in vivo. Keeping that in mind, the focus of this study was to understand the long term release study of silver ions for a period of minimum 6months from silver coated surface modified porous titanium implants. Implants were fabricated using a LENS™ system, a powder based additive manufacturing technique, with at least 25% volume porosity, with and without TiO 2 nanotubes in phosphate buffer saline (pH 7.4) to see if the total release of silver ions is within the toxic limit for human cells. Considering the fact that infection sites may reduce the local pH, silver release was also studied in acetate buffer (pH 5.0) for a period of 4weeks. Along with that, the osseointegrative properties as well as cytotoxicity of porous titanium implants were assessed in vivo for a period of 12weeks using a rat distal femur model. In vivo results indicate that porous titanium implants with silver coating show comparable, if not better, biocompatibility and bonding at the bone-implant interface negating any concerns related to toxicity related to silver to normal cells. The current research is based on our recently patented technology, however focused on understanding longer-term silver release to mitigate infection related problems in load-bearing implants that can even arise several months after the surgery. Prevention of orthopedic device related infection using antibiotics has met

A Novel Nonantibiotic Nitroglycerin-Based Catheter Lock Solution for Prevention of Intraluminal Central Venous Catheter Infections in Cancer Patients.

PubMed

Chaftari, Anne-Marie; Hachem, Ray; Szvalb, Ariel; Taremi, Mahnaz; Granwehr, Bruno; Viola, George Michael; Sapna, Amin; Assaf, Andrew; Numan, Yazan; Shah, Pankil; Gasitashvili, Ketevan; Natividad, Elizabeth; Jiang, Ying; Slack, Rebecca; Reitzel, Ruth; Rosenblatt, Joel; Mouhayar, Elie; Raad, Issam

2017-07-01

For long-term central lines (CL), the lumen is the major source of central line-associated bloodstream infections (CLABSI). The current standard of care for maintaining catheter patency includes flushing the CL with saline or heparin. Neither agent has any antimicrobial activity. Furthermore, heparin may enhance staphylococcal biofilm formation. We evaluated the safety and efficacy of a novel nonantibiotic catheter lock solution for the prevention of CLABSI. Between November 2015 and February 2016, we enrolled 60 patients with hematologic malignancies who had peripherally inserted central catheters (PICC) to receive the study lock solution. The study lock consisted of 15 or 30 μg/ml of nitroglycerin in combination with 4% sodium citrate and 22% ethanol. Each lumen was locked for at least 2 h once daily prior to being flushed. After enrollment of 10 patients at the lower nitroglycerin dose without evidence of toxicity, the dose was escalated to the higher dose (30 μg/ml). There were no serious related adverse events or episodes of hypotension with lock administration. Two patients experienced mild transient adverse events (one headache and one rash) possibly related to the lock and that resolved without residual effect. The CLABSI rate was 0 on lock days versus 1.6/1,000 catheter days (CD) off lock prophylaxis, compared with a rate of 1.9/1,000 CD at the institution in the same patient population. In conclusion, the nitroglycerin-based lock prophylaxis is safe and well tolerated. It may prevent CLABSI when given daily to cancer patients. Large, prospective, randomized clinical trials are needed to validate these findings. (This study has been registered at ClinicalTrials.gov under identifier NCT02577718.). Copyright © 2017 American Society for Microbiology.

Safety in tunnels : transport of dangerous goods through road tunnels : highlights

DOT National Transportation Integrated Search

2001-10-01

A serious incident involving dangerous goods in a tunnel can be extremely costly in terms of loss of human lives, environmental degradation, tunnel damage and transport disruption. On the other hand, needlessly banning dangerous goods from tunnels ma...

Long-term simulations of thermal and hydraulic characteristics in a mountain massif: The Mont Blanc case study, French and Italian Alps

NASA Astrophysics Data System (ADS)

Maréchal, J. C.; Perrochet, P.; Tacher, L.

1999-08-01

The use of hydrothermal simulation models to improve the prediction of water inflows in underground works during drilling is tested in the Mont Blanc tunnel, French and Italian Alps. The negative thermal anomaly that was observed during the drilling of this tunnel in 1960 is reproduced by long-term, transient hydrothermal simulations. Sensitivity analysis shows the great inertia of thermal phenomena at the massif scale. At the time of tunnel drilling, the massif had not reached thermal equilibrium. Therefore, a set of simulation scenarios, beginning at the end of the last glacial period, was designed to explain the anomaly encountered in the tunnel in 1960. The continuous cooling of alpine massifs due to infiltration of waters from the surface has occurred for 12,000 years and is expected to continue for about 100,000 years. Comparisons of water-discharge rates simulated in the tunnel with those observed indicate that this hydrothermal method is a useful tool for predicting water inflows in underground works.

Long-term Outcomes after Truncus Arteriosus Repair: A Single-center Experience for More than 40 Years.

PubMed

Asagai, Seiji; Inai, Kei; Shinohara, Tokuko; Tomimatsu, Hirofumi; Ishii, Tetsuko; Sugiyama, Hisashi; Park, In-Sam; Nagashima, Mitsugi; Nakanishi, Toshio

2016-12-01

This study aimed to analyze long-term survival and functional outcomes after truncus arteriosus repair in a single institution with more than 40 years of follow-up. Medical records were analyzed retrospectively in 52 patients who underwent the Rastelli procedure for truncus arteriosus repair between 1974 and 2002. Thirty-five patients survived the initial repair. The median age at the initial operation was 2.8 months (range, 0.1-123 months) and the body weight was 3.9 kg (range, 1.6 to 15.0 kg). The median age at follow-up was 23.6 years (range, 12.4 to 44.5 years). The median follow-up duration was 23.4 years (range, 12.3 to 40.7 years). The actuarial survival rate was 97% at 10 years and 93% at both 20 years and 40 years after the initial operation. At follow-up, most patients were in New York Heart Association (NYHA) functional classes I (73%) and II (24%). Thirty-six percent of patients had full-time jobs, 40% were students, and 21% were unemployed. Most patients (97%) had undergone conduit reoperations. Freedom from reoperation for right ventricular (RV) outflow and pulmonary artery (PA) stenosis was 59% at 5 years, 28% at 10 years, and 3% at 20 years after the initial operation. Freedom from catheter interventions for RV outflow and PA stenosis was 59% at 5 years, 47% at 10 years, and 38% at 20 years after the initial operation. Freedom from truncal valve replacement was 88% at 5 years, 85% at 10 years, and 70% at 20 years after the initial operation. In this single-center retrospective study, with long-term follow-up after repair of truncus arteriosus, long-term survival and functional outcomes were acceptable, despite the requirement for reoperation and multiple catheter interventions for RV outflow and PA stenosis in almost all patients, and the frequent requirement for late truncal valve operations. © 2016 The Authors. Congenital Heart Disease published by Wiley Periodicals, Inc.

Low-angled peripheral intravenous catheter tip placement decreases phlebitis.

PubMed

Tanabe, Hidenori; Murayama, Ryoko; Yabunaka, Koichi; Oe, Makoto; Takahashi, Toshiaki; Komiyama, Chieko; Sanada, Hiromi

2016-11-02

Peripheral intravenous catheters (PIVCs) are frequently removed due to phlebitis. We hypothesized that catheters made of polyurethane, which is more flexible than Teflon, would decrease phlebitis, and that flexibility could be estimated by measuring the catheter-tip angle. Ultrasonography in two groups of patients with different catheter types was then used to compare catheter-tip angles and phlebitis. Observational studies were carried out at a medical ward in a university hospital. Infusion therapy was administered to one group of patients in 2014 using Teflon catheters (control group, n = 200), and to another group of patients in 2015 using polyurethane catheters (investigational group, n = 207). The symptoms were assessed according to a scale developed by the Infusion Nurses Society. Long-axis ultrasonography images taken immediately before catheter removal were used to measure the angle between the central line of the catheter within 2 mm from the distal point and a tangent to the vessel wall. There were no significant differences between the two groups with respect to sex, age, and medical diagnosis. In the control and investigational groups, the rates of phlebitis were 37% (73/200) and 17% (36/207), respectively (p<0.001). The median angles of the catheter tip were 7.8° and 4.1°, respectively (p<0.001). Phlebitis occurred more frequently when the catheter-tip was placed at angle >5.8°. The frequency of phlebitis was lower in the polyurethane, in which the catheter was placed at lower angle, almost parallel to the vessel. Our results will aid in developing new catheters and in improving PIVC-securement techniques.

Intraluminal pneumatic lithotripsy for the removal of encrusted urinary catheters.

PubMed

Canby-Hagino, E D; Caballero, R D; Harmon, W J

1999-12-01

Urologists frequently treat patients requiring long-term urinary drainage with a percutaneous nephrostomy tube or ureteral stent. When such tubes are neglected and become encrusted, removal challenges even experienced urologists. We describe a new, minimally invasive technique for safely and rapidly removing encrusted, occluded tubes using the Swiss Lithoclast pneumatic lithotriptor. Patients presenting with an encrusted urinary catheter were evaluated by excretory urography for renal function and obstruction. Gentle manual extraction of the tube was attempted, followed by traditional extracorporeal shock wave lithotripsy and/or ureteroscopy. When the tube was not extracted, patients were then treated with intraluminal insertion of a pneumatic lithotripsy probe. One patient presented with an encrusted, occluded nephrostomy tube and 2 had an encrusted, occluded, indwelling ureteral stent. None was removed by manual traction. Intraluminal encrustations prevented the pigtail portions of these tubes from uncoiling and removal. In each case a pneumatic lithotripsy probe was inserted into the lumen of the catheter and advanced in a jackhammer-like fashion. This technique resulted in disruption of the intraluminal encrustations and straightening of the tubes so that they were removed in an atraumatic manner. Intraluminal pneumatic lithotripsy is a safe, easy and rapid technique for removing encrusted urinary catheters. It is unique in that the pneumatic lithotripsy probe functions in an aqueous and nonaqueous environment, and dislodges intraluminal calcifications. We recommend its use as first line treatment for removing encrusted urinary catheters.

Catheter indwell time and phlebitis development during peripheral intravenous catheter administration.

PubMed

Pasalioglu, Kadriye Burcu; Kaya, Hatice

2014-07-01

Intravenous catheters have been indispensable tools of modern medicine. Although intravenous applications can be used for a multitude of purposes, these applications may cause complications, some of which have serious effects. Of these complications, the most commonly observed is phlebitis. This study was conducted to determine the effect of catheter indwell time on phlebitis development during peripheral intravenous catheter administration. This study determined the effect of catheter indwell time on phlebitis development during peripheral intravenous catheter administration. The study included a total of 103 individuals who were administered 439 catheters and satisfied the study enrollment criteria at one infectious diseases clinic in Istanbul/Turkey. Data were compiled from Patient Information Forms, Peripheral Intravenous Catheter and Therapy Information Forms, reported grades based on the Visual Infusion Phlebitis Assessment Scale, and Peripheral Intravenous Catheter Nurse Observation Forms. The data were analyzed using SPSS. Results : The mean patient age was 53.75±15.54 (standard deviation) years, and 59.2% of the study participants were men. Phlebitis was detected in 41.2% of peripheral intravenous catheters, and the rate decreased with increased catheter indwell time. Analyses showed that catheter indwell time, antibiotic usage, sex, and catheterization sites were significantly associated with development of phlebitis. The results of this study show that catheters can be used for longer periods of time when administered under optimal conditions and with appropriate surveillance.

Effects of static fingertip loading on carpal tunnel pressure

NASA Technical Reports Server (NTRS)

Rempel, D.; Keir, P. J.; Smutz, W. P.; Hargens, A.

1997-01-01

The purpose of this study was to explore the relationship between carpal tunnel pressure and fingertip force during a simple pressing task. Carpal tunnel pressure was measured in 15 healthy volunteers by means of a saline-filled catheter inserted percutaneously into the carpal tunnel of the nondominant hand. The subjects pressed on a load cell with the tip of the index finger and with 0, 6, 9, and 12 N of force. The task was repeated in 10 wrist postures: neutral; 10 and 20 degrees of ulnar deviation; 10 degrees of radial deviation; and 15, 30, and 45 degrees of both flexion and extension. Fingertip loading significantly increased carpal tunnel pressure for all wrist angles (p = 0.0001). Post hoc analyses identified significant increase (p < 0.05) in carpal tunnel pressure between unloaded (0 N) and all loaded conditions, as well as between the 6 and 12 N load conditions. This study demonstrates that the process whereby fingertip loading elevates carpal tunnel pressure is independent of wrist posture and that relatively small fingertip loads have a large effect on carpal tunnel pressure. It also reveals the response characteristics of carpal tunnel pressure to fingertip loading, which is one step in understanding the relationship between sustained grip and pinch activities and the aggravation or development of median neuropathy at the wrist.

Instantons re-examined: dynamical tunneling and resonant tunneling.

PubMed

Le Deunff, Jérémy; Mouchet, Amaury

2010-04-01

Starting from trace formulas for the tunneling splittings (or decay rates) analytically continued in the complex time domain, we obtain explicit semiclassical expansions in terms of complex trajectories that are selected with appropriate complex-time paths. We show how this instantonlike approach, which takes advantage of an incomplete Wick rotation, accurately reproduces tunneling effects not only in the usual double-well potential but also in situations where a pure Wick rotation is insufficient, for instance dynamical tunneling or resonant tunneling. Even though only one-dimensional autonomous Hamiltonian systems are quantitatively studied, we discuss the relevance of our method for multidimensional and/or chaotic tunneling.

Antimicrobial-impregnated catheters for the prevention of catheter-related bloodstream infections.

PubMed

Lorente, Leonardo

2016-05-04

Central venous catheters are commonly used in critically ill patients. Such catheterization may entail mechanical and infectious complications. The interest in catheter-related infection lies in the morbidity, mortality and costs that it involved. Numerous contributions have been made in the prevention of catheter-related infection and the current review focuses on the possible current role of antimicrobial impregnated catheters to reduce catheter-related bloodstream infections (CRBSI). There is evidence that the use of chlorhexidine-silver sulfadiazine (CHSS), rifampicin-minocycline, or rifampicin-miconazol impregnated catheters reduce the incidence of CRBSI and costs. In addition, there are some clinical circumstances associated with higher risk of CRBSI, such as the venous catheter access and the presence of tracheostomy. Current guidelines for the prevention of CRBSI recommended the use of a CHSS or rifampicin-minocycline impregnated catheter in patients whose catheter is expected to remain in place > 5 d and if the CRBSI rate has not decreased after implementation of a comprehensive strategy to reduce it.

Antimicrobial-impregnated catheters for the prevention of catheter-related bloodstream infections

PubMed Central

Lorente, Leonardo

2016-01-01

Central venous catheters are commonly used in critically ill patients. Such catheterization may entail mechanical and infectious complications. The interest in catheter-related infection lies in the morbidity, mortality and costs that it involved. Numerous contributions have been made in the prevention of catheter-related infection and the current review focuses on the possible current role of antimicrobial impregnated catheters to reduce catheter-related bloodstream infections (CRBSI). There is evidence that the use of chlorhexidine-silver sulfadiazine (CHSS), rifampicin-minocycline, or rifampicin-miconazol impregnated catheters reduce the incidence of CRBSI and costs. In addition, there are some clinical circumstances associated with higher risk of CRBSI, such as the venous catheter access and the presence of tracheostomy. Current guidelines for the prevention of CRBSI recommended the use of a CHSS or rifampicin-minocycline impregnated catheter in patients whose catheter is expected to remain in place > 5 d and if the CRBSI rate has not decreased after implementation of a comprehensive strategy to reduce it. PMID:27152256

Immediate- and short-term outcome following recanalization of long chronic total occlusions (> 50 mm) of native coronary arteries with the Frontrunner catheter.

PubMed

Loli, Akil; Liu, Rex; Pershad, Ashish

2006-06-01

Thirty percent of diagnostic angiograms have at least 1 chronic total occlusion (CTO). The 10-year survival of patients with a CTO is improved if they have the CTO successfully recanalized. The success of recanalization with conventional wires is 50% and the impact of new technology on recanalization is unknown. This abstract reports a single center experience with one such new device, the Lumend Frontrunner catheter in revascularization of this difficult lesion subset. A consecutive series of 18 patients with CTO's of native coronary arteries were enrolled in this single center, single operator series. The mean age of the CTO was 5.3 years. The indication for attempt at recanalization was ischemia in the territory of the CTO on SPECT imaging. Success was defined as TIMI flow restoration and < 40% residual stenosis. Primary success (defined as TIMI 3 Flow restoration and < 40% residual stenosis) was achieved in 77% of patients. At 30 days and out to 6 months, clinical TVR was 11% (2/18) in this difficult lesion subset. Conventional predictors of failure to recanalize CTOs do not appear to hold true with the use of the Frontrunner catheter. In this small series, dual cusp injections and use of the Microglide catheter appears to correlate with favorable outcomes. Fluoroscopy times and contrast use are high when attempting recanalization of CTOs with this technology.

Super-long bridges with floating towers: the role of multi-box decks and Hardware-In-the-Loop technology for wind tunnel tests

NASA Astrophysics Data System (ADS)

Zasso, A.; Argentini, T.; Bayati, I.; Belloli, M.; Rocchi, D.

2017-12-01

The super long fjord crossings in E39 Norwegian project pose new challenges to long span bridge design and construction technology. Proposed solutions should consider the adoption of bridge deck with super long spans or floating solutions for at least one of the towers, due to the relevant fjord depth. At the same time, the exposed fjord environment, possibly facing the open ocean, calls for higher aerodynamic stability performances. In relation to this scenario, the present paper addresses two topics: 1) the aerodynamic advantages of multi-box deck sections in terms of aeroelastic stability, and 2) an experimental setup in a wind tunnel able to simulate the aeroelastic bridge response including the wave forcing on the floating.

Infraclavicular versus axillary nerve catheters: A retrospective comparison of early catheter failure rate.

PubMed

Quast, Michaela B; Sviggum, Hans P; Hanson, Andrew C; Stoike, David E; Martin, David P; Niesen, Adam D

2018-05-01

Continuous brachial plexus catheters are often used to decrease pain following elbow surgery. This investigation aimed to assess the rate of early failure of infraclavicular (IC) and axillary (AX) nerve catheters following elbow surgery. Retrospective study. Postoperative recovery unit and inpatient hospital floor. 328 patients who received IC or AX nerve catheters and underwent elbow surgery were identified by retrospective query of our institution's database. Data collected included unplanned catheter dislodgement, catheter replacement rate, postoperative pain scores, and opioid administration on postoperative day 1. Catheter failure was defined as unplanned dislodging within 24 h of placement or requirement for catheter replacement and evaluated using a covariate adjusted model. 119 IC catheters and 209 AX catheters were evaluated. There were 8 (6.7%) failed IC catheters versus 13 (6.2%) failed AX catheters. After adjusting for age, BMI, and gender there was no difference in catheter failure rate between IC and AX nerve catheters (p = 0.449). These results suggest that IC and AX nerve catheters do not differ in the rate of early catheter failure, despite differences in anatomic location and catheter placement techniques. Both techniques provided effective postoperative analgesia with median pain scores < 3/10 for patients following elbow surgery. Reasons other than rate of early catheter failure should dictate which approach is performed. Copyright © 2018. Published by Elsevier Inc.

[Long-term psychiatric hospitalizations].

PubMed

Plancke, L; Amariei, A

2017-02-01

Long-term hospitalizations in psychiatry raise the question of desocialisation of the patients and the inherent costs. Individual indicators were extracted from a medical administrative database containing full-time psychiatric hospitalizations for the period 2011-2013 of people over 16 years old living in the French region of Nord-Pas-de-Calais. We calculated the proportion of people who had experienced a hospitalization with a duration of 292 days or more during the study period. A bivariate analysis was conducted, then ecological data (level of health-care offer, the deprivation index and the size of the municipalities of residence) were included into a multilevel regression model in order to identify the factors significantly related to variability of long-term hospitalization rates. Among hospitalized individuals in psychiatry, 2.6% had had at least one hospitalization of 292 days or more during the observation period; the number of days in long-term hospitalization represented 22.5% of the total of days of full-time hospitalization in psychiatry. The bivariate analysis revealed that seniority in the psychiatric system was strongly correlated with long hospitalization rates. In the multivariate analysis, the individual indicators the most related to an increased risk of long-term hospitalization were: total lack of autonomy (OR=9.0; 95% CI: 6.7-12.2; P<001); diagnoses of psychological development disorders (OR=9.7; CI95%: 4.5-20.6; P<.001); mental retardation (OR=4.5; CI95%: 2.5-8.2; P<.001): schizophrenia (OR=3.0; CI95%: 1.7-5.2; P<.001); compulsory hospitalization (OR=1.7; CI95%: 1.4-2.1; P<.001); having experienced therapeutic isolation (OR=1.8; CI95%: 1.5-2.1; P<.001). Variations of long-term hospitalization rates depending on the type of establishment were very high, but the density of hospital beds or intensity of ambulatory activity services were not significantly linked to long-term hospitalization. The inhabitants of small urban units had

Catheter indwell time and phlebitis development during peripheral intravenous catheter administration

PubMed Central

Pasalioglu, Kadriye Burcu; Kaya, Hatice

2014-01-01

Objective: Intravenous catheters have been indispensable tools of modern medicine. Although intravenous applications can be used for a multitude of purposes, these applications may cause complications, some of which have serious effects. Of these complications, the most commonly observed is phlebitis. This study was conducted to determine the effect of catheter indwell time on phlebitis development during peripheral intravenous catheter administration. Methods: This study determined the effect of catheter indwell time on phlebitis development during peripheral intravenous catheter administration. The study included a total of 103 individuals who were administered 439 catheters and satisfied the study enrollment criteria at one infectious diseases clinic in Istanbul/Turkey. Data were compiled from Patient Information Forms, Peripheral Intravenous Catheter and Therapy Information Forms, reported grades based on the Visual Infusion Phlebitis Assessment Scale, and Peripheral Intravenous Catheter Nurse Observation Forms. The data were analyzed using SPSS. Results : The mean patient age was 53.75±15.54 (standard deviation) years, and 59.2% of the study participants were men. Phlebitis was detected in 41.2% of peripheral intravenous catheters, and the rate decreased with increased catheter indwell time. Analyses showed that catheter indwell time, antibiotic usage, sex, and catheterization sites were significantly associated with development of phlebitis. Conclusion: The results of this study show that catheters can be used for longer periods of time when administered under optimal conditions and with appropriate surveillance. PMID:25097505

Reduction of Thrombosis and Bacterial Infection via Controlled Nitric Oxide (NO) Release from S-Nitroso-N-acetylpenicillamine (SNAP) Impregnated CarboSil Intravascular Catheters

PubMed Central

2017-01-01

Nitric oxide (NO) has many important physiological functions, including its ability to inhibit platelet activation and serve as potent antimicrobial agent. The multiple roles of NO in vivo have led to great interest in the development of biomaterials that can deliver NO for specific biomedical applications. Herein, we report a simple solvent impregnation technique to incorporate a nontoxic NO donor, S-nitroso-N-acetylpenicillamine (SNAP), into a more biocompatible biomedical grade polymer, CarboSil 20 80A. The resulting polymer-crystal composite material yields a very stable, long-term NO release biomaterial. The SNAP impregnation process is carefully characterized and optimized, and it is shown that SNAP crystal formation occurs in the bulk of the polymer after solvent evaporation. LC-MS results demonstrate that more than 70% of NO release from this new composite material originates from the SNAP embedded CarboSil phase, and not from the SNAP species leaching out into the soaking solution. Catheters prepared with CarboSil and then impregnated with 15 wt % SNAP provide a controlled NO release over a 14 d period at physiologically relevant fluxes and are shown to significantly reduce long-term (14 day) bacterial biofilm formation against Staphylococcus epidermidis and Pseudonomas aeruginosa in a CDC bioreactor model. After 7 h of catheter implantation in the jugular veins of rabbit, the SNAP CarboSil catheters exhibit a 96% reduction in thrombus area (0.03 ± 0.01 cm2/catheter) compared to the controls (0.84 ± 0.19 cm2/catheter) (n = 3). These results suggest that SNAP impregnated CarboSil can become an attractive new biomaterial for use in preparing intravascular catheters and other implanted medical devices. PMID:28317023

Shoshin beriberi induced by long-term administration of diuretics: a case report.

PubMed

Misumida, Naoki; Umeda, Hisashi; Iwase, Mitsunori

2014-01-01

Previous studies have suggested that diuretic therapy for heart failure may lead to thiamine deficiency due to the increased urinary thiamine excretion. Herein, we present the case of a 61-year-old man with shoshin beriberi, a fulminant form of wet beriberi, induced by long-term diuretic therapy. The patient had a history of heart failure with preserved ejection fraction and was receiving furosemide and trichlormethiazide therapy. He presented with worsening exertional dyspnea and was admitted for heart failure exacerbation. His condition failed to improve even after intensive treatment. A hemodynamic evaluation with the Swan-Ganz catheter revealed high-output heart failure with low peripheral vascular resistance. Thiamine was administered for suspected shoshin beriberi; his hemodynamic status improved dramatically within the next six hours. The serum thiamine level was below the normal range; the patient was therefore diagnosed with shoshin beriberi. The common causes of thiamine deficiency were not identified. Long-term diuretic therapy with furosemide and thiazide was thought to have played a major role in the development of thiamine deficiency. This case illustrates the importance of considering wet beriberi as a possible cause of heart failure exacerbation in patients taking diuretics, even when the common thiamine deficiency causes are not identified with history-taking.

Long-term potentiation and long-term depression: a clinical perspective

PubMed Central

Bliss, Timothy V.P.; Cooke, Sam F

2011-01-01

Long-term potentiation and long-term depression are enduring changes in synaptic strength, induced by specific patterns of synaptic activity, that have received much attention as cellular models of information storage in the central nervous system. Work in a number of brain regions, from the spinal cord to the cerebral cortex, and in many animal species, ranging from invertebrates to humans, has demonstrated a reliable capacity for chemical synapses to undergo lasting changes in efficacy in response to a variety of induction protocols. In addition to their physiological relevance, long-term potentiation and depression may have important clinical applications. A growing insight into the molecular mechanisms underlying these processes, and technological advances in non-invasive manipulation of brain activity, now puts us at the threshold of harnessing long-term potentiation and depression and other forms of synaptic, cellular and circuit plasticity to manipulate synaptic strength in the human nervous system. Drugs may be used to erase or treat pathological synaptic states and non-invasive stimulation devices may be used to artificially induce synaptic plasticity to ameliorate conditions arising from disrupted synaptic drive. These approaches hold promise for the treatment of a variety of neurological conditions, including neuropathic pain, epilepsy, depression, amblyopia, tinnitus and stroke. PMID:21779718

Comparison of delayed complications of central venous catheters placed surgically or radiologically in pediatric oncology patients.

PubMed

Basford, Tavis J; Poenaru, Dan; Silva, Mariana

2003-05-01

Pediatric central venous catheters (CVCs) traditionally have been placed surgically, guided by anatomic landmarks. Increasingly, interventional radiology services are inserting CVCs using ultrasound image guidance. This study compares the frequency of delayed complications in CVCs placed surgically or radiologically in a pediatric oncology population. Data on CVCs placed in one academic institution over 10 years were collected and analyzed retrospectively. Main outcomes assessed were infectious complications, mechanical complications, and premature catheter removal. Ninety-eight CVCs-comprising 52 external tunneled catheters (ETCs) and 46 subcutaneous ports-were assessed in 67 patients. Median patient age was 6.1 years for children with external catheters and 7.8 years for those with ports. Both infectious and mechanical complications were significantly more common among surgically placed ETCs than those placed radiologically (P <.05). Complications per 1,000 catheter days and premature removal showed a trend toward greater frequency among surgical ETCs, although this did not reach statistical significance. No consistent trends were seen in complications among ports. Pediatric patients with CVCs, especially those with external catheters, experience frequent delayed complications. Patients with radiologically inserted ETCs may encounter fewer complications than those with surgically placed ones. This corroborates previous reports in the literature suggesting image-guided CVC placement as a preferable alternative to traditional techniques. Copyright 2003 Elsevier Inc. All rights reserved.

Unsuitable value of abdominal fat tissue aspirate examination for the diagnosis of amyloidosis in long-term hemodialysis patients.

PubMed

Orfila, C; Goffinet, F; Goudable, C; Eche, J P; Ton That, H; Manuel, Y; Suc, J M

1988-01-01

Abdominal fat tissue aspiration was used in 22 long-term hemodialysis patients (5-17 years). Fourteen of these patients had carpal tunnel syndrome and amyloid deposits of beta 2-microglobulin in the synovium. One patient had a spontaneous rupture of the spleen with amyloid deposits in spleen vessels. Seven other patients presented carpal tunnel syndrome and/or articular pains, and radiological lytic lesions in bone, strongly suggesting an amyloid origin. As a control group, in 22 patients with biopsy-proven amyloidosis, abdominal fat tissue aspirates were performed and were studied under the same conditions: by light microscopy these tissues were stained with Congo red and examined with a polarizing microscope; these specimens were also studied by electron microscopy. In all hemodialyzed patients, no amyloid deposit was present in fat tissue with Congo red staining and by electron microscopy. On the contrary, amyloid was observed in 17 of 22 cases in other types of amyloidosis. It seems that this method which has been proved to be simple and sensitive for the diagnosis of systemic amyloidosis is not a good marker for the presence of amyloid in long-term hemodialysis patients.

Fibrin Sheath Angioplasty: A Technique to Prevent Superior Vena Cava Stenosis Secondary to Dialysis Catheters

PubMed Central

Hacker, Robert I.; Garcia, Lorena De Marco; Chawla, Ankur; Panetta, Thomas F.

2012-01-01

Fibrin sheaths are a heterogeneous matrix of cells and debris that form around catheters and are a known cause of central venous stenosis and catheter failure. A total of 50 cases of central venous catheter fibrin sheath angioplasty (FSA) after catheter removal or exchange are presented. A retrospective review of an outpatient office database identified 70 eligible patients over a 19-month period. After informed consent was obtained, the dialysis catheter exiting the skin was clamped, amputated, and a wire was inserted. The catheter was then removed and a 9-French sheath was inserted into the superior vena cava, a venogram was performed. If a fibrin sheath was present, angioplasty was performed using an 8 × 4 or 10 × 4 balloon along the entire length of the fibrin sheath. A completion venogram was performed to document obliteration of the sheath. During the study, 50 patients were diagnosed with a fibrin sheath, and 43 had no pre-existing central venous stenosis. After FSA, 39 of the 43 patient's (91%) central systems remained patent without the need for subsequent interventions; 3 patients (7%) developed subclavian stenoses requiring repeat angioplasty and stenting; 1 patent (2.3%) developed an occlusion requiring a reintervention. Seven patients with prior central stenosis required multiple angioplasties; five required stenting of their central lesions. Every patient had follow-up fistulograms to document long-term patency. We propose that FSA is a prudent and safe procedure that may help reduce the risk of central venous stenosis from fibrin sheaths due to central venous catheters. PMID:23997555

Long-term influence of body mass index on cardiovascular events after atrial fibrillation ablation.

PubMed

Bunch, T Jared; May, Heidi T; Bair, Tami L; Crandall, Brian G; Cutler, Michael J; Jacobs, Victoria; Mallender, Charles; Muhlestein, Joseph B; Osborn, Jeffrey S; Weiss, J Peter; Day, John D

2016-09-01

Catheter ablation of atrial fibrillation (AF) is an established therapeutic rhythm approach in symptomatic patients. Obesity is a dominant driver of AF recurrence after ablation. However, being both overweight and underweight drives long-term cardiac and general health risks. Long-term data are needed to understand the influence of body mass index (BMI) on outcomes after ablation in regard to arrhythmia recurrence and cardiovascular outcomes. All patients who underwent an index ablation with a BMI recorded and at least 3 years of follow-up were included (n = 1558). The group was separated and compared by index ablation BMI status (≤20, 21-25, 26-30, >30 kg/m(2)). Long-term outcomes included AF recurrence, stroke/TIA, heart failure (HF) hospitalization, and death. Patients with advancing BMI status were more likely to be male and have hypertension, a smoking history, diabetes, HF, and a prior cardioversion. Patients with a BMI ≤20 were more likely to have a moderate-high congestive heart failure, hypertension, age >75, diabetes, stroke (CHADS2) score. At 3 years, recurrence rates of AF increased significantly with increasing BMI status (p = 0.02); paradoxically, there was a trend for increased stroke risk with decreasing BMI (p = 0.06). Long-term death rates tended to increase inversely with BMI status, and HF rates were greatest in the highest and lowest BMI groups. Lower weight at AF ablation lowers arrhythmia recurrence risk. However, AF ablation patients who are normal or underweight remain at high risk of other cardiovascular outcomes including increased stroke risk with less AF burden.

Clinically apparent long-term electric disturbances in the acute and very long-term of patent foramen ovale device-based closure.

PubMed

Rigatelli, Gianluca; Zuin, Marco; Pedon, Luigi; Zecchel, Roberto; Dell'Avvocata, Fabio; Carrozza, Antonio; Zennaro, Marco; Pastore, Gianni; Zanon, Francesco

2017-03-01

Incidence of electrical disturbances in patients submitted to transcatheter patent foramen ovale (PFO) closure has not been fully clarified in a large population. The aim of the study is to assess the incidence of atrial fibrillation, supraventricular tachi-arrhythmias, and atrio-ventricular block in the acute and very long-term follow-up. We reviewed the medical and instrumental data of 1000 consecutive patients (mean age 47.3±17.1years) prospectively enrolled in two centers over a 13-year period (February 1999 to February 2012) for right-to-left (R-to-L) shunt ICE-aided catheter-based closure using different devices. Successful transcatheter PFO closure was achieved in 99.8% of the patients. Implanted devices were: Amplatzer PFO Occluder in 463 patients (46.3%), Amplatzer ASD Cribriform Occluder in 420 patients (42.0%), Premere Occlusion System in 95 patients (9.5%), and Biostar Occluder in 22 patients (2.2%). Postprocedural electrical complications occurred in 5.9% of patients. The only independent predictors of electrophysiological complications were female gender (OR 2.3, 0.5-5.1 [95% CI], p<0.001) and device disk >30mm (OR 5.0, 1.2-7.2 [95% CI], p<0.001). On a mean follow-up of 12 .3±0.6years (minimum 4- maximum 17years), electrical complications occurred in 1.4% of patients including one only case of complete AVB and 5 cases of permanent AF. The only independent predictors were female gender (OR 2.3, 0.5-5.1 [95% CI], p<0.001) and device disk >30mm (OR 5.0, 1.2-7.2 [95% CI], p<0.001). Device-based closure of PFO using different devices, appeared very safe from an electrophysiological point of view with low incidence of electrical disturbances even in the very long-term follow-up. Copyright © 2016 Elsevier Inc. All rights reserved.

Exit site and tunnel infections in children on chronic peritoneal dialysis: findings from the Standardizing Care to Improve Outcomes in Pediatric End Stage Renal Disease (SCOPE) Collaborative.

PubMed

Swartz, Sarah J; Neu, Alicia; Skversky Mason, Amy; Richardson, Troy; Rodean, Jonathan; Lawlor, John; Warady, Bradley; Somers, Michael J G

2018-06-01

The Standardizing Care to Improve Outcomes in Pediatric End Stage Renal Disease (SCOPE) Collaborative is a quality improvement initiative to reduce dialysis-associated infections. The frequency of peritoneal dialysis (PD) catheter exit site infection (ESI) and variables influencing its development and end result are unclear. We sought to determine ESI rates, to elucidate the epidemiology, risk factors, and outcomes for ESI, and to assess for association between provider compliance with care bundles and ESI risk. We reviewed demographic, dialysis and ESI data, and care bundle adherence and outcomes for SCOPE enrollees from October 2011 to September 2014. ESI involved only the exit site, only the subcutaneous catheter tunnel, or both. A total of 857 catheter insertions occurred in 734 children over 10,110 cumulative months of PD provided to these children. During this period 207 ESIs arose in 124 children or 0.25 ESIs per dialysis year. Median time to ESI was 392 days, with 69% of ESIs involving exit site only, 23% involving the tunnel only, and 8% involving both sites. Peritonitis developed in 6%. ESI incidence was associated with age (p = 0.003), being the lowest in children aged < 2 years and highest in those aged 6-12 years, and with no documented review of site care or an exit site score  of > 0 at prior month's visit (p < 0.001). Gender, race, end stage renal disease etiology, exit site orientation, catheter cuff number or mobilization, and presence of G-tube, stoma, or vesicostomy were unassociated with ESI incidence. Of the ESIs reported, 71% resolved with treatment, 24% required hospitalization, and 9% required catheter removal, generally secondary to tunnel infection. Exit site infections occur at an annualized rate of 0.25, typically well into the dialysis course. Younger patient age and documented review of site care are associated with lower ESI rates. Although most ESIs resolve, hospitalization is frequent, and tunnel involvement/catheter

A randomized controlled trial comparing mupirocin versus Polysporin Triple for the prevention of catheter-related infections in peritoneal dialysis patients (the MP3 study).

PubMed

Jassal, Sarbjit V; Lok, Charmaine E

2008-01-01

Peritonitis remains the most serious complication of peritoneal dialysis (PD). Gram-positive organisms are among the most common causes of PD peritonitis; however, recent trends show increasing rates of gram-negative and fungal infections. Strategies to prevent peritonitis include the use of prophylactic topical mupirocin at the site where the PD catheter exits from the abdominal wall; however, mupirocin does not afford protection against gram-negative or fungal infections. The aim of this study is to determine if the incidence of catheter-related infections (exit-site infection, tunnel infection, or peritonitis) is significantly reduced by the routine application of Polysporin Triple antibiotic ointment (Pfizer Canada, Markham, Ontario, Canada) in comparison to mupirocin ointment. The Mupirocin Versus Polysporin Triple Study (MP3) is a multicenter, randomized, double-blinded controlled study comparing Polysporin Triple (P3) against the current standard of care. The aim of the study is to recruit 200 patients being treated with or starting on PD and randomize them to receive either mupirocin or P3 at the catheter exit site. Patients will be followed for 18 months or until death or transfer from PD to an alternate treatment modality. The primary outcome will be the time to first catheter-related infection. Catheter-related infections will be strictly defined using current guidelines and categorized into exit-site infections, infective peritonitis, or tunnel infections. The primary analysis will be an intention-to-treat analysis. The results of this study will help determine if the use of P3 is superior to mupirocin ointment in the prevention of catheter-related infections and will help guide evidence-based best practices.

Role of Catheter-directed Thrombolysis in Management of Iliofemoral Deep Venous Thrombosis.

PubMed

Chen, James X; Sudheendra, Deepak; Stavropoulos, S William; Nadolski, Gregory J

2016-01-01

The treatment for iliofemoral deep venous thrombosis (DVT) is challenging, as the use of anticoagulation alone can be insufficient for restoring venous patency and thus lead to prolongation of acute symptoms and an increased risk of chronic complications, including venous insufficiency and postthrombotic syndrome (PTS). In these cases, earlier and more complete thrombus removal can ameliorate acute symptoms and reduce long-term sequelae. Endovascular therapies involving the use of pharmacologic, mechanical, and combined pharmacomechanical modalities have been developed to achieve these goals. The most frequently used of these techniques, catheter-directed thrombolysis (CDT), involves the infusion of a thrombolytic agent through a multiple-side-hole catheter placed within the thrombosed vein to achieve high local doses and thereby break down the clot while minimizing systemic thrombolytic agent exposure. Randomized controlled trial results have indicated decreased PTS rates and improved venous patency rates in patients treated with CDT compared with these rates in patients treated with anticoagulation. The use of newer pharmacomechanical techniques, as compared with conventional CDT, reduces procedural times and thrombolytic agent doses and is the subject of ongoing investigations. Endovascular thrombus removal techniques offer a means to improve venous valvular function and decrease the risk of debilitating long-term complications such as PTS and are a promising option for treating patients with iliofemoral DVT. (©)RSNA, 2016.

A magnetic-resonance-imaging-compatible remote catheter navigation system.

PubMed

Tavallaei, Mohammad Ali; Thakur, Yogesh; Haider, Syed; Drangova, Maria

2013-04-01

A remote catheter navigation system compatible with magnetic resonance imaging (MRI) has been developed to facilitate MRI-guided catheterization procedures. The interventionalist's conventional motions (axial motion and rotation) on an input catheter - acting as the master - are measured by a pair of optical encoders, and a custom embedded system relays the motions to a pair of ultrasonic motors. The ultrasonic motors drive the patient catheter (slave) within the MRI scanner, replicating the motion of the input catheter. The performance of the remote catheter navigation system was evaluated in terms of accuracy and delay of motion replication outside and within the bore of the magnet. While inside the scanner bore, motion accuracy was characterized during the acquisition of frequently used imaging sequences, including real-time gradient echo. The effect of the catheter navigation system on image signal-to-noise ratio (SNR) was also evaluated. The results show that the master-slave system has a maximum time delay of 41 ± 21 ms in replicating motion; an absolute value error of 2 ± 2° was measured for radial catheter motion replication over 360° and 1.0 ± 0.8 mm in axial catheter motion replication over 100 mm of travel. The worst-case SNR drop was observed to be 2.5%.

Contact force with magnetic-guided catheter ablation.

PubMed

Bessière, Francis; Zikry, Christopher; Rivard, Lena; Dyrda, Katia; Khairy, Paul

2018-05-01

Achieving adequate catheter tip-tissue contact is essential for delivering robust radiofrequency (RF) ablation lesions. We measured the contact force generated by a remote magnetic-guided catheter navigation system. A plexiglass model with an integrated scale was fashioned to mimic transvenous and retrograde access to sites in the right atrium and right and left ventricles. An 8 Fr RF ablation catheter was steered by remote magnetic guidance at fields of 0.08 and 0.10 T, with and without a long sheath positioned at the entrance of the chamber. Ten contact force readings were taken at each setting, with the scale recalibrated prior to each measurement. Generalized estimating equations were used to compare contact force measurements while adjusting for the non-independent data structure. A total of 240 contact force measurements were taken. Without a long sheath, contact forces with magnetic fields of 0.10 T (n = 60) and 0.08 T (n = 60) were similar (6.1 ± 1.4 g vs. 6.0 ± 1.3 g, P = 0.089). Contact forces were not significantly different with simulated transvenous (n = 80) and retrograde aortic (n = 40) approaches (6.2 ± 1.4 g vs. 5.7 ± 1.2 g, P = 0.132). The contact force increased substantially with a long sheath (P < 0.001) and was significantly higher with 0.10 T (n = 60) vs. 0.08 T (n = 60) fields (20.4 ± 0.6 g vs. 18.0 ± 0.5 g, P < 0.001). Magnetic fields of 0.08 and 0.10 T provide stable catheter contact forces, as reflected by the small variability between measurements. The average contact force is approximately 6 g without a sheath and increases to 20 g with a long sheath positioned at the entrance of the chamber of interest.

Long-term clinical and radiological outcome of endovascular embolization of pancreatitis-related pseudoaneurysms.

PubMed

Vander Mijnsbrugge, Ward; Laleman, Wim; Van Steenbergen, Werner; Heye, Sam; Verslype, Chris; Maleux, Geert

2017-03-01

Background Long-term outcome after embolization of pancreatitis-induced pseudoaneurysm is not yet determined. Purpose To assess the long-term efficacy and patients' overall survival after embolization of pancreatitis-induced pseudoaneurysm. Material and Methods Patients referred for endovascular treatment of a pancreatitis-induced pseudoaneurysm between January 1998 and January 2014 were analyzed. Embolization procedures were performed by transcatheter techniques using different types of embolic agents. Demographic, technical-radiological, and clinical data were collected. Results Thirty-four patients were identified with a pancreatitis-induced pseudoaneurysm; the underlying disease was acute (n = 13; 38%) or chronic (n = 21; 62%) pancreatitis; seven patients (20.6%) had active bleeding when embolized, while in the remaining 27 patients (79.4%) the pseudoaneurysm was not bleeding. In all 34 patients, successful endovascular exclusion of the pseudoaneurysm was obtained after the first attempt. Minor complications occurred in 11 patients (30%); no major complications were noted. A new pseudoaneurysm on a different vessel was identified during follow-up in three patients (9%). In another patient (3%), the excluded pseudoaneurysm reopened during follow-up. All four recurrences occurred within the first 5 months after embolization. Long-term follow-up (mean, 6.6 years; range, 4 months-16 years) revealed estimated survival rates of 94%, 89%, and 75% after 2, 5, and 10 years respectively, without pseudoaneurysm-related death. Conclusion Catheter-directed embolization of pancreatitis-induced pseudoaneurysms is relatively safe and effective. Recurrence or new pseudoaneurysm formation was low and occurred within the first 6 months after embolization. Overall survival is high, with no pseudoaneurysm-related deaths.

3D-Printed Patient-Specific ACL Femoral Tunnel Guide from MRI.

PubMed

Rankin, Iain; Rehman, Haroon; Frame, Mark

2018-01-01

Traditional ACL reconstruction with non-anatomic techniques can demonstrate unsatisfactory long-term outcomes with regards instability and the degenerative knee changes observed with these results. Anatomic ACL reconstruction attempts to closely reproduce the patient's individual anatomic characteristics with the aim of restoring knee kinematics, in order to improve patient short and long-term outcomes. We designed an arthroscopic, patient-specific, ACL femoral tunnel guide to aid anatomical placement of the ACL graft within the femoral tunnel. The guide design was based on MRI scan of the subject's uninjured contralateral knee, identifying the femoral footprint and its anatomical position relative to the borders of the femoral articular cartilage. Image processing software was used to create a 3D computer aided design which was subsequently exported to a 3D-printing service. Transparent acrylic based photopolymer, PA220 plastic and 316L stainless steel patient-specific ACL femoral tunnel guides were created; the models produced were accurate with no statistical difference in size and positioning of the center of the ACL femoral footprint guide to MRI ( p =0.344, p =0.189, p =0.233 respectively). The guides aim to provide accurate marking of the starting point of the femoral tunnel in arthroscopic ACL reconstruction. This study serves as a proof of concept for the accurate creation of 3D-printed patient-specific guides for the anatomical placement of the femoral tunnel during ACL reconstruction.

A prospective randomized trial comparing Foley catheter, oxytocin, and combination Foley catheter-oxytocin for labour induction with unfavourable cervix.

PubMed

El Khouly, Nabih I

2017-04-01

The purpose of this study was to evaluate the effectiveness and safety of transcervical Foley catheter with and without oxytocin versus oxytocin alone for labour induction with unfavourable cervix. This trial enrolled 108 women with singleton pregnancies presented for labour induction with unfavourable cervix. Patients were randomly assigned to receive Foley catheter alone (I), Foley catheter plus oxytocin (II) or oxytocin alone (III). Outcomes were analysed in terms of success of induction, induction delivery interval, route of delivery, dose and duration of oxytocin, and complications. Successful normal vaginal delivery was more common in group I (p = .02) compared to group III. Induction delivery time was statistically shorter in group II and group III (p < .001). Patients in group I required significantly less oxytocin dose and duration (p < .001). This led to our conclusion that induction of labour with Foley catheter without oxytocin increases success rate of normal vaginal delivery; however, it has a longer induction delivery interval with similar complications.

Are birds stressed during long-term flights? A wind-tunnel study on circulating corticosterone in the red knot.

PubMed

Jenni-Eiermann, Susanne; Hasselquist, Dennis; Lindström, Ake; Koolhaas, Anita; Piersma, Theunis

2009-01-01

During endurance flight most birds do not feed and have to rely on their body reserves. Fat and protein is catabolised to meet the high energetic demands. Even though the hormonal regulation of migration is complex and not yet fully understood, the adrenocortical hormone corticosterone crystallizes to play a major role in controlling physiological traits in migratory birds during flight. However, results from field studies are partially equivocal, not least because data from birds during endurance flight are hard to get and present mostly a momentary shot. A wind-tunnel experiment offered the possibility to measure repeatedly under controlled conditions the effect of long flights on the stress hormone corticosterone. In a long-distance migrating shorebird, the red knot Calidris canutus, we measured plasma concentrations of corticosterone within 3 min and after a restraint time of 30 min directly after 2h and 10h non-stop flights, respectively, and during rest. Baseline corticosterone levels were unchanged directly after the flights, indicating that endurance flight did not affect corticosterone levels. The adrenocortical response to restraint showed the typical rise in birds during rest, while birds after a 2 or 10h flight substantially decreased plasma corticosterone concentrations. We suggest that the negative adrenocortical response to restraint after flight is part of the mechanism to reduce the proteolytic effect of corticosterone to save muscle protein and to avoid muscle damaging effects.

Long-term outcome of 154 patients receiving balloon-occluded retrograde transvenous obliteration for gastric fundal varices.

PubMed

Imai, Yukinori; Nakazawa, Manabu; Ando, Satsuki; Sugawara, Kayoko; Mochida, Satoshi

2016-11-01

This study aims to clarify the long-term outcome of therapeutic strategies including balloon-occluded retrograde transvenous obliteration (B-RTO) for patients with gastric fundal varices. The subjects were 154 patients with gastric fundal varices fulfilling the criteria for receiving B-RTO. In patients showing variceal bleeding, endoscopic therapies and/or balloon tamponade was performed to achieve hemostasis. B-RTO was accomplished with injection of 5% ethanolamine oleate through a standard balloon catheter except for patients with atypical varices, in whom a microballoon catheter was used to occlude drainage vessels other than a gastrorenal shunt. In patients complicated with esophageal varices at baseline, endoscopic therapies were performed following B-RTO. Balloon-occluded retrograde transvenous obliteration was performed successfully in 147 patients (95%), including 15 patients using a microballoon catheter. Complete variceal obliteration was achieved in all patients. Additional endoscopic therapies for esophageal varices were performed in 31 patients. Gastric varices did not recur in any of these patients. The cumulative survival rates at 1, 3, and 5 years after B-RTO were 91%, 76%, and 72%, respectively. Child-Pugh scores and hepatocellular carcinoma complication were identified as prognostic factors associated with survival rates. The cumulative exacerbation rates of esophageal varices at 1, 3, and 5 years were 13%, 20%, and 27%, respectively, and rupture developed in six patients, which were successfully treated with endoscopic therapies. Therapeutic strategies including B-RTO with a microballoon catheter were useful to achieve a favorable outcome in patients with gastric fundal varices especially in those manifesting Child-Pugh class-A liver damage and/or those without hepatocellular carcinoma complication. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Candida tropicalis biofilms: artificial urine, urinary catheters and flow model.

PubMed

Negri, Melyssa; Silva, Sónia; Henriques, Mariana; Azeredo, Joana; Svidzinski, Terezinha; Oliveira, Rosário

2011-10-01

Adhesion to medical devices and biofilm formation are considered important virulence factors of Candida tropicalis. This work aimed to use artificial urine (AU) and urinary catheters, under flow conditions, for studying C. tropicalis biofilms. Adhesion and biofilm formation on silicone and latex urinary catheters were quantified by crystal violet staining and determination of colony forming units. Candida surface hydrophobicity was also evaluated, as well as the biofilms' matrix content in terms of proteins and carbohydrates. Candida tropicalis was able to adhere and to form biofilms along the entire length of the catheters under flow conditions. It was found that the isolate U69 adhered significantly more to both types of catheters than did the reference strain. However, U69 biofilms contained significantly less cultivable cells and higher biofilm biomass than those of the reference strain. Detachment of cells from biofilms on latex catheter was lower compared to silicone catheter. This model using AU appeared to be suitable for studies mimicking the real body conditions. Additionally, C. tropicalis was in fact able to colonize urinary catheters in the presence of AU and to detach from these catheters, demonstrating their capacity to colonize distal sites.

Antibiofilm surface functionalization of catheters by magnesium fluoride nanoparticles

PubMed Central

Lellouche, Jonathan; Friedman, Alexandra; Lahmi, Roxanne; Gedanken, Aharon; Banin, Ehud

2012-01-01

The ability of bacteria to colonize catheters is a major cause of infection. In the current study, catheters were surface-modified with MgF2 nanoparticles (NPs) using a sonochemical synthesis protocol described previously. The one-step synthesis and coating procedure yielded a homogenous MgF2 NP layer on both the inside and outside of the catheter, as analyzed by high resolution scanning electron microscopy and energy dispersive spectroscopy. The coating thickness varied from approximately 750 nm to 1000 nm on the inner walls and from approximately 450 nm to approximately 580 nm for the outer wall. The coating consisted of spherical MgF2 NPs with an average diameter of approximately 25 nm. These MgF2 NP-modified catheters were investigated for their ability to restrict bacterial biofilm formation. Two bacterial strains most commonly associated with catheter infections, Escherichia coli and Staphylococcus aureus, were cultured in tryptic soy broth, artificial urine and human plasma on the modified catheters. The MgF2 NP-coated catheters were able to significantly reduce bacterial colonization for a period of 1 week compared to the uncoated control. Finally, the potential cytotoxicity of MgF2 NPs was also evaluated using human and mammalian cell lines and no significant reduction in the mitochondrial metabolism was observed. Taken together, our results indicate that the surface modification of catheters with MgF2 NPs can be effective in preventing bacterial colonization and can provide catheters with long-lasting self-sterilizing properties. PMID:22419866

Near-Term Actions to Address Long-Term Climate Risk

NASA Astrophysics Data System (ADS)

Lempert, R. J.

2014-12-01

Addressing climate change requires effective long-term policy making, which occurs when reflecting on potential events decades or more in the future causes policy makers to choose near-term actions different than those they would otherwise pursue. Contrary to some expectations, policy makers do sometimes make such long-term decisions, but not as commonly and successfully as climate change may require. In recent years however, the new capabilities of analytic decision support tools, combined with improved understanding of cognitive and organizational behaviors, has significantly improved the methods available for organizations to manage longer-term climate risks. In particular, these tools allow decision makers to understand what near-term actions consistently contribute to achieving both short- and long-term societal goals, even in the face of deep uncertainty regarding the long-term future. This talk will describe applications of these approaches for infrastructure, water, and flood risk management planning, as well as studies of how near-term choices about policy architectures can affect long-term greenhouse gas emission reduction pathways.

Does cranberry have a role in catheter-associated urinary tract infections?

PubMed

Thomas, Dominique; Rutman, Matthew; Cooper, Kimberly; Abrams, Andrew; Finkelstein, Julia; Chughtai, Bilal

2017-11-01

Catheter-associated urinary tract infections (CA-UTIs) are a prevalent and costly condition, with very few therapeutic options. We sought to evaluate the efficacy of an oral cranberry supplement on CA-UTIs over a six-month period. Subjects with long-term indwelling catheters and recurrent symptomatic CA-UTIs were enrolled to take a once-daily oral cranberry supplement with 36 mg of the active ingredient proanthocyanidin (PACs). Primary outcome was reducing the number of symptomatic CA-UTIs. This was defined by ≥10 3 (cfu)/mL of ≥1 bacterial species in a single catheter urine specimen and signs and symptoms compatible with CA-UTI. Secondary outcomes included bacterial counts and resistance patterns to antibiotics. Thirty-four patients were enrolled in the trial; 22 patients (mean age 77.22 years, 77.27% were men) completed the study. Cranberry was effective in reducing the number of symptomatic CA-UTIs in all patients (n=22). Resistance to antibiotics was reduced by 28%. Furthermore, colony counts were reduced by 58.65%. No subjects had adverse events while taking cranberry. The cranberry supplement reduced the number of symptomatic CA-UTIs, antibiotic resistances, and major causative organisms in this cohort. Larger, placebo-controlled studies are needed to further define the role of cranberry in CA-UTIs.

Persistent Atrial Fibrillation Ablation using the Tip-Versatile Ablation Catheter.

PubMed

Davies, Edward J; Clayton, Ben; Lines, Ian; Haywood, Guy A

2016-07-01

The mechanisms by which persistent atrial fibrillation (PsAF) develops are incompletely understood. Consequently, the optimal strategy for the ablative management of PsAF remains debated. Current methods are often time consuming, complex and non-reproducible. We assessed the Tip-Versatile Ablation Catheter (T-VAC) technique, a rapidly delivered, empirical technique based on the box-set concept using duty-cycled linear catheter ablation technology. Forty-four procedures in 40 patients undergoing PsAF ablation with the novel technique were prospectively entered onto a database: 27 de novo. Primary endpoint was freedom from arrhythmia at over two-year follow-up. Secondary endpoints were time to first arrhythmia recurrence, freedom from atrial fibrillation (AF) on and off antiarrhythmic drugs (AAD), procedural and fluoroscopy duration and complication rate. At mean follow-up of 33 months, absolute freedom from arrhythmia recurrence was 45% in the de novo group. Overall, at 33 (IQR 24-63) months, 60% of de novo patients were in sustained normal sinus rhythm and a further 15% reported only occasional paroxysms of AF at long-term follow-up. Procedure time was 192±25 mins, total energy delivered 2239±883s and fluoroscopy time was 60±10mins. In selected patients with persistent AF, a long-term rate of 60% arrhythmia free survival off AAD can be achieved using this novel T-VAC technique. Copyright © 2016 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.

Intraperitoneal Urinary Bladder Perforation with Pneumoperitoneum in Association with Indwelling Foley Catheter Diagnosed in Emergency Department.

PubMed

Zhan, Chenyang; Maria, Pedro P; Dym, R Joshua

2017-11-01

Indwelling Foley catheter is a rare cause of urinary bladder perforation, a serious injury with high mortality that demands accurate and prompt diagnosis. While the gold standard for diagnosis of bladder injury is computed tomography (CT) cystography, few bladder ruptures associated with Foley catheter have been reported to be diagnosed in the emergency department (ED). An 83-year-old man with indwelling Foley catheter presented to the ED for hematuria and altered mental status. He was diagnosed to have intraperitoneal rupture of the urinary bladder in the ED using abdominal and pelvic CT without contrast, which demonstrated bladder wall discontinuity, intraperitoneal free fluid, and pneumoperitoneum. The patient was treated successfully with medical management and bladder drainage. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: To our knowledge, this is the first report of intraperitoneal urinary bladder perforation associated with Foley catheter diagnosed in the ED by CT without contrast. Pneumoperitoneum found in this case was a clue to the diagnosis and is a benign finding that does not necessitate urgent surgical intervention. The early and accurate diagnosis in this case allowed for effective management with good clinical outcome. The use of indwelling Foley catheter has a high prevalence, especially in long-term care facility residents, who are frequent visitors in the ED. Therefore, emergency physicians and radiologists should be familiar with the presentation and imaging findings of this potential injury associated with Foley catheters. Copyright © 2017 Elsevier Inc. All rights reserved.

Application of self-expandable metal stents for ureteroileal anastomotic strictures: long-term results.

PubMed

Liatsikos, Evangelos N; Kagadis, George C; Karnabatidis, Dimitrios; Katsanos, Konstantinos; Papathanassiou, Zafiria; Constantinides, Constantinos; Perimenis, Petros; Nikiforidis, George C; Stolzenburg, Jens-Uwe; Siablis, Dimitrios

2007-07-01

We report our long-term experience with the management of benign ureteroileal anastomotic strictures using self-expandable metal stents. A total of 16 male and 2 female patients with a mean+/-SD age of 72+/-7 years (range 66 to 78) with benign fibrotic strictures at the site of ureteroileal anastomosis underwent implantation of self-expandable metal stents with a nominal diameter of 6 to 8 mm. A total of 24 ureteroileal conduits were treated. The external nephrostomy tubes were removed after fluoroscopic validation of ureteral patency. Patients were followed with blood biochemistry, ultrasonography, urography and/or virtual endoscopy. Retrograde external-internal catheter insertion through the cutaneous stoma was performed in cases of recalcitrant stricture. The technical success rate of ureteroileal stricture crossing and stenting was 100% (24 of 24 cases). Mean followup was 21 months (range 7 to 50). The clinical success rate during the immediate post-stenting period was 70.8% (17 of 24 cases). The 1 and 4-year primary patency rates were 37.8% and 22.7%, respectively. Secondary interventions included repeat balloon dilation in 15 ureters, of which 8 also underwent subsequent coaxial stent placement. The 1 and 4-year secondary patency rates were 64.8% and 56.7%, respectively. Except in 2 patients who died external-internal Double-J catheters continued to be inserted retrograde in 6 ureteroileal conduits. They are periodically exchanged to prevent mucous inspissation and stent encrustation. Metal stents served as the definitive treatment for stricture in more than half of the cases, whereas in the remainder the stents allowed the uncomplicated and regular exchange of Double-J catheters in retrograde fashion. This combined, less invasive treatment for ureteroileal anastomotic strictures may help patients avoid surgical revision and preserve quality of life.

Successful Salvage of Central Venous Catheters in Patients with Catheter-Related or Central Line-Associated Bloodstream Infections by Using a Catheter Lock Solution Consisting of Minocycline, EDTA, and 25% Ethanol

PubMed Central

Chaftari, Anne-Marie; Zakhour, Ramia; Jordan, Mary; Al Hamal, Zanaib; Jiang, Ying; Yousif, Ammar; Garoge, Kumait; Mulanovich, Victor; Viola, George M.; Kanj, Soha; Pravinkumar, Egbert; Rosenblatt, Joel; Hachem, Ray

2016-01-01

In cancer patients with long-term central venous catheters (CVC), removal and reinsertion of a new CVC at a different site might be difficult because of the unavailability of accessible vascular sites. In vitro and animal studies showed that a minocycline-EDTA-ethanol (M-EDTA-EtOH) lock solution may eradicate microbial organisms in biofilms, hence enabling the treatment of central line-associated bloodstream infections (CLABSI) while retaining the catheter in situ. Between April 2013 and July 2014, we enrolled 30 patients with CLABSI in a prospective study and compared them to a historical group of 60 patients with CLABSI who had their CVC removed and a new CVC inserted. Each catheter lumen was locked with an M-EDTA-EtOH solution for 2 h administered once daily, for a total of 7 doses. Patients who received locks had clinical characteristics that were comparable to those of the control group. The times to fever resolution and microbiological eradication were similar in the two groups. Patients with the lock intervention received a shorter duration of systemic antibiotic therapy than that of the control patients (median, 11 days versus 16 days, respectively; P < 0.0001), and they were able to retain their CVCs for a median of 74 days after the onset of bacteremia. The M-EDTA-EtOH lock was associated with a significantly decreased rate of mechanical and infectious complications compared to that of the CVC removal/reinsertion group, who received a longer duration of systemic antimicrobial therapy. (This study has been registered at ClinicalTrials.gov under registration no. NCT01539343.) PMID:27001822

A National Implementation Project to Prevent Catheter-Associated Urinary Tract Infection in Nursing Home Residents.

PubMed

Mody, Lona; Greene, M Todd; Meddings, Jennifer; Krein, Sarah L; McNamara, Sara E; Trautner, Barbara W; Ratz, David; Stone, Nimalie D; Min, Lillian; Schweon, Steven J; Rolle, Andrew J; Olmsted, Russell N; Burwen, Dale R; Battles, James; Edson, Barbara; Saint, Sanjay

2017-08-01

Catheter-associated urinary tract infection (UTI) in nursing home residents is a common cause of sepsis, hospital admission, and antimicrobial use leading to colonization with multidrug-resistant organisms. To develop, implement, and evaluate an intervention to reduce catheter-associated UTI. A large-scale prospective implementation project was conducted in community-based nursing homes participating in the Agency for Healthcare Research and Quality Safety Program for Long-Term Care. Nursing homes across 48 states, Washington DC, and Puerto Rico participated. Implementation of the project was conducted between March 1, 2014, and August 31, 2016. The project was implemented over 12-month cohorts and included a technical bundle: catheter removal, aseptic insertion, using regular assessments, training for catheter care, and incontinence care planning, as well as a socioadaptive bundle emphasizing leadership, resident and family engagement, and effective communication. Urinary catheter use and catheter-associated UTI rates using National Healthcare Safety Network definitions were collected. Facility-level urine culture order rates were also obtained. Random-effects negative binomial regression models were used to examine changes in catheter-associated UTI, catheter utilization, and urine cultures and adjusted for covariates including ownership, bed size, provision of subacute care, 5-star rating, presence of an infection control committee, and an infection preventionist. In 4 cohorts over 30 months, 568 community-based nursing homes were recruited; 404 met inclusion criteria for analysis. The unadjusted catheter-associated UTI rates decreased from 6.78 to 2.63 infections per 1000 catheter-days. With use of the regression model and adjustment for facility characteristics, the rates decreased from 6.42 to 3.33 (incidence rate ratio [IRR], 0.46; 95% CI, 0.36-0.58; P < .001). Catheter utilization was 4.5% at baseline and 4.9% at the end of the project. Catheter

Impact of quality management monitoring and intervention on central venous catheter dysfunction in the outpatient chemotherapy infusion setting.

PubMed

Bansal, Anu; Binkert, Christoph A; Robinson, Malcolm K; Shulman, Lawrence N; Pellerin, Linda; Davison, Brian

2008-08-01

To assess the utility of maintaining and analyzing a quality-management database while investigating a subjectively perceived increase in the incidence of tunneled catheter and port dysfunction in a cohort of oncology outpatients. All 152 patients undergoing lytic therapy (2-4 mg alteplase) of a malfunctioning indwelling central venous catheter (CVC) from January through June 2004 at a single cancer center in the United States were included in a quality-management database. Patients were categorized by time to device failure and the initial method of catheter placement (surgery vs interventional radiology). Data were analyzed after 3 months, and areas of possible improvement were identified and acted upon. Three months of follow-up data were then collected and similarly analyzed. In a 6-month period, 152 patients treated for catheter malfunction received a total of 276 doses of lytic therapy. A 3-month interim analysis revealed a disproportionately high rate (34%) of early catheter malfunction (ECM; <30 days from placement). Postplacement radiographs demonstrated suboptimal catheter positioning in 67% of these patients, all of whom had surgical catheter placement. There was a 50% absolute decrease in the number of patients presenting with catheter malfunction in the period from April through June (P < .001). Evaluation of postplacement radiographs in these patients demonstrated a 50% decrease in the incidence of suboptimal positioning (P < .05). Suboptimal positioning was likely responsible for some, but not all, cases of ECM. Maintenance of a quality-management database is a relatively simple intervention that can have a clear and important impact on the quality and cost of patient care.

The quest for durable lesions in catheter ablation of atrial fibrillation - technological advances in radiofrequency catheters and balloon devices.

PubMed

Maurer, Tilman; Kuck, Karl-Heinz

2017-08-01

Atrial fibrillation is the most common cardiac arrhythmia and represents a growing clinical, social and economic challenge. Catheter ablation for symptomatic atrial fibrillation has evolved from an experimental procedure into a widespread therapy and offers a safe and effective treatment option. A prerequisite for durable PVI are transmural and contiguous circumferential lesions around the pulmonary veins. However, electrical reconnection of initially isolated pulmonary veins remains a primary concern and is a dominant factor for arrhythmia recurrence during long-term follow up. Areas covered: This article discusses the physiology of lesion formation using radiofrequency-, cryo- or laser- energy for pulmonary vein isolation and provides a detailed review of recent technological advancements in the field of radiofrequency catheters and balloon devices. Finally, future directions and upcoming developments for the interventional treatment of atrial fibrillation are discussed. Expert commentary: Durable conduction block across deployed myocardial lesions is mandatory not only for PVI but for any other cardiac ablation strategy as well. A major improvement urgently expected is the intraprocedural real-time distinction of durable lesions from interposed gaps with only transiently impaired electrical conduction. Furthermore, a simplification of ablation tools used for PVI is required to reduce the high technical complexity of the procedure.

Textile for heart valve prostheses: fabric long-term durability testing.

PubMed

Heim, Frederic; Durand, Bernard; Chakfe, Nabil

2010-01-01

The rapid developments and success in percutaneous vascular surgery over the last two decades with the now common stent grafts implantation, make the noninvasive surgery technique today attractive even for heart valve replacement. Less traumatic for the patient and also less time consuming, percutaneous heart valve replacement is however at its beginning and restricted to end of life patients. The noninvasive procedure expects from the heart valve prosthesis material to be resistant and adapted to folding requirements of the implantation process (catheter). Polyester fabric could be a suited material for heart valve implanted percutaneously. Highly flexible and resistant, polyester fabric proved to be well adapted to the dynamic behavior of a valve and polyester (Dacron) is also widely used for vascular grafts implantation and shows good biocompatibility and durability. However, today there's no data available on long-term durability of fabric used as heart valve material. The purpose of this work is to study the long term behavior of a microdenier polyester fabric construction under combined in vitro flexure and tension fatigue stress. In the novel in vitro testing technique presented, a fabric specimen was subjected to combined flexural and tensile fatigue generated by fluid flow under physiological pressure conditions. The results obtained show how flexural properties change with fatigue time, which reflects directly on the suitability of a fabric in such devices. It was also observed that these fabric structural changes directly influence the in vitro behavior of the textile heart valve prosthesis. (c) 2009 Wiley Periodicals, Inc.

Wind Tunnel Test Technique and Instrumentation Development at LaRC

NASA Technical Reports Server (NTRS)

Putnam, Lawrence E.

1999-01-01

LaRC has an aggressive test technique development program underway. This program has been developed using 3rd Generation R&D management techniques and is a closely coordinated program between suppliers and wind tunnel operators- wind tunnel customers' informal input relative to their needs has been an essential ingredient in developing the research portfolio. An attempt has been made to balance this portfolio to meet near term and long term test technique needs. Major efforts are underway to develop techniques for determining model wing twist and location of boundary layer transition in the NTF (National Transonic Facility). The foundation of all new instrumentation developments, procurements, and upgrades will be based on uncertainty analysis.

Tunneling decay of false vortices

NASA Astrophysics Data System (ADS)

Lee, Bum-Hoon; Lee, Wonwoo; MacKenzie, Richard; Paranjape, M. B.; Yajnik, U. A.; Yeom, Dong-han

2013-10-01

We consider the decay of vortices trapped in the false vacuum of a theory of scalar electrodynamics in 2+1 dimensions. The potential is inspired by models with intermediate symmetry breaking to a metastable vacuum that completely breaks a U(1) symmetry, while in the true vacuum, the symmetry is unbroken. The false vacuum is unstable through the formation of true vacuum bubbles; however, the rate of decay can be extremely long. On the other hand, the false vacuum can contain metastable vortex solutions. These vortices contain the true vacuum inside in addition to a unit of magnetic flux and the appropriate topologically nontrivial false vacuum outside. We numerically establish the existence of vortex solutions which are classically stable; however, they can decay via tunneling. In general terms, they tunnel to a configuration which is a large, thin-walled vortex configuration that is now classically unstable to the expansion of its radius. We compute an estimate for the tunneling amplitude in the semiclassical approximation. We believe our analysis would be relevant to superconducting thin films or superfluids.

A Novel Microwave Catheter Can Perform Noncontact Circumferential Endocardial Ablation in a Model of Pulmonary Vein Isolation.

PubMed

Qian, Pierre; Barry, Michael Anthony; Nguyen, Trang; Ross, David; Kovoor, Pramesh; McEwan, Alistair; Thomas, Stuart; Thiagalingam, Aravinda

2015-07-01

Pulmonary vein isolation is an effective treatment for atrial fibrillation. Current endocardial ablation techniques require catheter contact for lesion formation. Inadequate or inconsistent catheter contact results in difficulty with achieving acute and long-term isolation and consequent atrial arrhythmia recurrence. Microwave energy produces radiant heating and therefore can be used for noncontact catheter ablation. We hypothesized that it is possible to design a microwave catheter to produce a circumferential transmural thermal lesion in an in vitro model of a pulmonary vein antrum. A monopole microwave catheter with a sideways firing axially symmetrical heating pattern was designed. Noncontact ablations were performed in a perfused pulmonary vein model constructed from microwave myocardial phantom embedded with a sheet of thermochromic liquid crystal to permit visualization and measurement of thermal lesions from color changes. 1200 J ablations were performed at 150 W for 80 seconds and 120 W for 100 seconds at high (0.8 L/min) and low (0.06 L/min) flow through the modeled pulmonary vein. Myocardial tissue was substituted for the phantom material and ablations repeated at 150 W for 180 seconds and stained with nitro-blue tetrazolium. The catheter was able to induce deep circumferential antral lesions in myocardial phantom and myocardial tissue. Higher power and shorter ablations delivering the same amount of microwave energy resulted in larger lesions with less surface sparing. A microwave catheter can be designed to produce a circumferential thermal lesion on noncontact ablation and may have possible applications for pulmonary vein isolation. © 2015 Wiley Periodicals, Inc.

Long-Term Tracking of a Specific Vehicle Using Airborne Optical Camera Systems

NASA Astrophysics Data System (ADS)

Kurz, F.; Rosenbaum, D.; Runge, H.; Cerra, D.; Mattyus, G.; Reinartz, P.

2016-06-01

In this paper we present two low cost, airborne sensor systems capable of long-term vehicle tracking. Based on the properties of the sensors, a method for automatic real-time, long-term tracking of individual vehicles is presented. This combines the detection and tracking of the vehicle in low frame rate image sequences and applies the lagged Cell Transmission Model (CTM) to handle longer tracking outages occurring in complex traffic situations, e.g. tunnels. The CTM model uses the traffic conditions in the proximities of the target vehicle and estimates its motion to predict the position where it reappears. The method is validated on an airborne image sequence acquired from a helicopter. Several reference vehicles are tracked within a range of 500m in a complex urban traffic situation. An artificial tracking outage of 240m is simulated, which is handled by the CTM. For this, all the vehicles in the close proximity are automatically detected and tracked to estimate the basic density-flow relations of the CTM model. Finally, the real and simulated trajectories of the reference vehicles in the outage are compared showing good correspondence also in congested traffic situations.

Pigtail catheters used for percutaneous fluid drainage: comparison of performance characteristics.

PubMed

Macha, Douglas B; Thomas, John; Nelson, Rendon C

2006-03-01

To compare the performance characteristics of various single-lumen all-purpose pigtail drainage catheters. The following parameters were compared: flow rates between catheters of the same size, whether changing the fluid viscosity has any effect on catheter comparisons, the effect on flow of leaving an open three-way stopcock in the drainage pathway, the tendency of the catheters to kink, and catheter patency after kinking, as measured according to flow. All-purpose 8.0-, 8.3-, and 8.5-F (collectively referred to as 8-F); 10.0-, 10.2-, and 10.3-F (collectively referred to as 10-F); and 12.0-F pigtail drainage catheters from three manufacturers were evaluated. Data were compared by using two-tailed t tests after normal distributions were confirmed. P < .05 was considered to represent a significant difference. At comparison of the 8-F catheters, the C.R. Bard catheters demonstrated better flow rates than the Cook and Boston Scientific devices. Among the 10-F catheters, there were no significant differences in the flow rates of fluid with viscosity equivalent to that of water between the C.R. Bard and Boston Scientific catheters; however, both these catheter types demonstrated significantly (P < .05) better flow rates than the Cook devices. Among the 12-F catheters, the C.R. Bard catheters demonstrated significantly (P < .05) better flow rates than the other two catheter types. Changing the fluid viscosity caused no changes in comparison results. In all catheter groups, the presence of a stopcock significantly (P < .05) impaired flow. None of the evaluated catheters demonstrated a clear advantage in terms of patency or susceptibility to kinking. At comparison of the in vitro performances of catheters from different manufacturers, the C.R. Bard 8.0-F and Cook 10.2-F catheters had comparable flow rates, and flow rates through the C.R. Bard and Boston Scientific 10.0-F catheters were comparable to flow rates through the Cook and Boston Scientific 12.0-F catheters

Wind tunnel technology for the development of future commercial aircraft

NASA Technical Reports Server (NTRS)

Szodruch, J.

1986-01-01

Requirements for new technologies in the area of civil aircraft design are mainly related to the high cost involved in the purchase of modern, fuel saving aircraft. A second important factor is the long term rise in the price of fuel. The demonstration of the benefits of new technologies, as far as these are related to aerodynamics, will,for the foreseeable future, still be based on wind tunnel measurements. Theoretical computation methods are very successfully used in design work, wing optimization, and an estimation of the Reynolds number effect. However, wind tunnel tests are still needed to verify the feasibility of the considered concepts. Along with other costs, the cost for the wind tunnel tests needed for the development of an aircraft is steadily increasing. The present investigation is concerned with the effect of numerical aerodynamics and civil aircraft technology on the development of wind tunnels. Attention is given to the requirements for the wind tunnel, investigative methods, measurement technology, models, and the relation between wind tunnel experiments and theoretical methods.

Compensation for Unconstrained Catheter Shaft Motion in Cardiac Catheters

PubMed Central

Degirmenci, Alperen; Loschak, Paul M.; Tschabrunn, Cory M.; Anter, Elad; Howe, Robert D.

2016-01-01

Cardiac catheterization with ultrasound (US) imaging catheters provides real time US imaging from within the heart, but manually navigating a four degree of freedom (DOF) imaging catheter is difficult and requires extensive training. Existing work has demonstrated robotic catheter steering in constrained bench top environments. Closed-loop control in an unconstrained setting, such as patient vasculature, remains a significant challenge due to friction, backlash, and physiological disturbances. In this paper we present a new method for closed-loop control of the catheter tip that can accurately and robustly steer 4-DOF cardiac catheters and other flexible manipulators despite these effects. The performance of the system is demonstrated in a vasculature phantom and an in vivo porcine animal model. During bench top studies the robotic system converged to the desired US imager pose with sub-millimeter and sub-degree-level accuracy. During animal trials the system achieved 2.0 mm and 0.65° accuracy. Accurate and robust robotic navigation of flexible manipulators will enable enhanced visualization and treatment during procedures. PMID:27525170

Materials Handling for Urban Tunneling in Rock

DOT National Transportation Integrated Search

1979-01-01

An examination of prior forecasts of tunnel construction provides an estimate of 2.4 million feet of rock tunnel to be constructed during the 1976-2000 period. Tunnel projects for the near term (1980+) and far term (1990+) periods are defined for stu...

Tunnel junction based memristors as artificial synapses

PubMed Central

Thomas, Andy; Niehörster, Stefan; Fabretti, Savio; Shepheard, Norman; Kuschel, Olga; Küpper, Karsten; Wollschläger, Joachim; Krzysteczko, Patryk; Chicca, Elisabetta

2015-01-01

We prepared magnesia, tantalum oxide, and barium titanate based tunnel junction structures and investigated their memristive properties. The low amplitudes of the resistance change in these types of junctions are the major obstacle for their use. Here, we increased the amplitude of the resistance change from 10% up to 100%. Utilizing the memristive properties, we looked into the use of the junction structures as artificial synapses. We observed analogs of long-term potentiation, long-term depression and spike-time dependent plasticity in these simple two terminal devices. Finally, we suggest a possible pathway of these devices toward their integration in neuromorphic systems for storing analog synaptic weights and supporting the implementation of biologically plausible learning mechanisms. PMID:26217173

Placement of a Port Catheter Through Collateral Veins in a Patient with Central Venous Occlusion

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

Teichgraeber, Ulf Karl-Martin, E-mail: ulf.teichgraeber@charite.de; Streitparth, Florian, E-mail: florian.streitparth@charite.d; Gebauer, Bernhard, E-mail: bernhard.gebauer@charite.d

Long-term utilization of central venous catheters (CVCs) for parenteral nutrition has a high incidence of central venous complications including infections, occlusions, and stenosis. We report the case of a 31-year-old woman presenting with a malabsorption caused by short gut syndrome due to congenital aganglionic megacolon. The patient developed a chronic occlusion of all central neck and femoral veins due to long-term use of multiple CVCs over more than 20 years. In patients with central venous occlusion and venous transformation, the implantation of a totally implanted port system by accessing collateral veins is an option to continue long-term parenteral nutrition whenmore » required. A 0.014-in. Whisper guidewire (Terumo, Tokyo) with high flexibility and steerability was chosen to maneuver and pass through the collateral veins. We suggest this approach to avoid unfavorable translumbar or transhepatic central venous access and to conserve the anatomically limited number of percutaneous access sites.« less

Electron tunnelling through single azurin molecules can be on/off switched by voltage pulses

NASA Astrophysics Data System (ADS)

Baldacchini, Chiara; Kumar, Vivek; Bizzarri, Anna Rita; Cannistraro, Salvatore

2015-05-01

Redox metalloproteins are emerging as promising candidates for future bio-optoelectronic and nano-biomemory devices, and the control of their electron transfer properties through external signals is still a crucial task. Here, we show that a reversible on/off switching of the electron current tunnelling through a single protein can be achieved in azurin protein molecules adsorbed on gold surfaces, by applying appropriate voltage pulses through a scanning tunnelling microscope tip. The observed changes in the hybrid system tunnelling properties are discussed in terms of long-sustained charging of the protein milieu.

Safety Evaluation of the Lighting at the Entrance of a Very Long Road Tunnel: A Case Study in Ilam.

PubMed

Mehri, Ahmad; Hajizadeh, Roohalah; Farhang Dehghan, Somayeh; Nassiri, Parvin; Jafari, Sayed Mohammad; Taheri, Fereshteh; Zakerian, Seyed Abolfazl

2017-06-01

At the entrance of a tunnel, reflection of sunlight from the surrounding environment and a lack of adequate lighting usually cause some vision problems. The purpose of this study was to perform a safety evaluation of lighting on a very long road in Ilam, Iran. The average luminance was measured using a luminance meter (model S3; Hagner, Solna, Sweden). A camera (model 108, 35-mm single-lens reflex; Yashica, Nagano, Japan) was used to take photographs of the safe stopping distance from the tunnel entrance. Equivalent luminance was determined according to the Holliday polar diagram. Considering the average luminance at the tunnel entrance (116.7 cd/m 2 ) and using Adrian's equation, the safe level of lighting at the entrance of the tunnel was determined to be 0.7. A comparison between the results of the safe levels of lighting at the entrance of the tunnel and the De Boer scale showed that the phenomenon of black holes is created at the tunnel entrance. This may lead to a misadaptation of the drivers' eyes to the change in luminance level at the entrance of the tunnel, thereby increasing the risk of road accidents in this zone.

Long-term solar-terrestrial observations

NASA Technical Reports Server (NTRS)

1988-01-01

The results of an 18-month study of the requirements for long-term monitoring and archiving of solar-terrestrial data is presented. The value of long-term solar-terrestrial observations is discussed together with parameters, associated measurements, and observational problem areas in each of the solar-terrestrial links (the sun, the interplanetary medium, the magnetosphere, and the thermosphere-ionosphere). Some recommendations are offered for coordinated planning for long-term solar-terrestrial observations.

Catheter-related bloodstream infection.

PubMed

Goede, Matthew R; Coopersmith, Craig M

2009-04-01

Catheter-related bloodstream infections (CR-BSIs) are a common, frequently preventable complication of central venous catheterization. CR-BSIs can be prevented by strict attention to insertion and maintenance of central venous catheters and removing unneeded catheters as soon as possible. Antiseptic- or antibiotic-impregnated catheters are also an effective tool to prevent infections. The diagnosis of CR-BSI is made largely based on culture results. CR-BSIs should always be treated with antibiotics, and except in rare circumstances the infected catheter needs to be removed.

The geologic, geomorphic, and hydrologic context underlying options for long-term management of the Spirit Lake outlet near Mount St. Helens, Washington

USGS Publications Warehouse

Grant, Gordon E.; Major, Jon J.; Lewis, Sarah L.

2017-01-01

The 1980 eruption of Mount St. Helens produced a massive landslide and consequent pyroclastic currents, deposits of which blocked the outlet to Spirit Lake. Without an outlet, the lake began to rise, threatening a breaching of the blockage and release of a massive volume of water. To mitigate the hazard posed by the rising lake and provide an outlet, in 1984–1985 the U.S. Army Corps of Engineers bored a 2.6-km (8,500-ft) long tunnel through a bedrock ridge on the western edge of the lake. Locally, the tunnel crosses weak rock along faults, and external pressures in these weak zones have caused rock heave and support failures, which have necessitated periodic major repairs. During its more than 30-year lifetime, the tunnel has maintained the level of Spirit Lake at a safe elevation. The lake approaches its maximum safe operating level only when the tunnel closes for repair. The most recent major repair in early 2016 highlights the need for a reliable outlet that does not require repeated and expensive interventions and extended closures. The U.S. Forest Service, U.S. Army Corps of Engineers, and U.S. Geological Survey developed, reviewed, and analyzed an array of options for a long-term plan to remove the threat of catastrophic failure of the tunnel. In this report, we (1) provide background on natural hazards that can affect existing and alternative infrastructure; (2) evaluate the potential for tunnel failure and consequent breaching of the blockage posed by the current tunnel infrastructure; (3) evaluate potential consequences to downstream communities and infrastructure in the event of a catastrophic breaching of the blockage; (4) evaluate potential risks associated with alternative lake outlets; and (5) identify data and knowledge gaps that need to be addressed to fully evaluate options available to management.

Tunneling probe of fluctuating superconductivity in disordered thin films

NASA Astrophysics Data System (ADS)

Dentelski, David; Frydman, Aviad; Shimshoni, Efrat; Dalla Torre, Emanuele G.

2018-03-01

Disordered thin films close to the superconductor-insulator phase transition (SIT) hold the key to understanding quantum phase transition in strongly correlated materials. The SIT is governed by superconducting quantum fluctuations, which can be revealed, for example, by tunneling measurements. These experiments detect a spectral gap, accompanied by suppressed coherence peaks, on both sides of the transition. Here we describe the insulating side in terms of a fluctuating superconducting field with finite-range correlations. We perform a controlled diagrammatic resummation and derive analytic expressions for the tunneling differential conductance. We find that short-range superconducting fluctuations suppress the coherence peaks even in the presence of long-range correlations. Our approach offers a quantitative description of existing measurements on disordered thin films and accounts for tunneling spectra with suppressed coherence peaks.

Long-term care: long-term care insurance--2005. End of Year Issue Brief.

PubMed

Tanner, Rachel; Bercaw, Lawren

2005-12-31

As the "Baby Boom" generation approaches retirement, state and federal lawmakers are struggling to ensure that the nation's long-term care system will provide adequate services for the growing number of senior citizens. A 2003 Administration on Aging report predicted that the elderly population will double by 2030. Accordingly, policymakers must prepare for the impending squeeze on public health and Medicaid resources. Many consumers are exploring private long-term care insurance options as a means of preparing for the cost of eldercare. Yet, a lack of market uniformity has rendered the long-term care insurance industry somewhat difficult for consumers to decipher. In addition, senior care insurance is often costly, particularly for those over age 50.

A central venous catheter coated with benzalkonium chloride for the prevention of catheter-related microbial colonization.

PubMed

Moss, H A; Tebbs, S E; Faroqui, M H; Herbst, T; Isaac, J L; Brown, J; Elliott, T S

2000-11-01

In an attempt to overcome infections associated with central venous catheters, a new antiseptic central venous catheter coated with benzalkonium chloride on the internal and external surfaces has been developed and evaluated in a clinical trial. Patients (235) randomly received either a triple-lumen central venous catheter coated with benzalkonium chloride (117) or a polyurethane non-antiseptic catheter (118). The incidence of microbial colonization of both catheters and retained antiseptic activity of the benzalkonium chloride device following removal were determined. The benzalkonium chloride resulted in a significant reduction of the incidence of microbial colonization on both the internal and external catheter surfaces. The reduction in colonization was detected at both the intradermal (21 benzalkonium chloride catheters vs. 38 controls, P = 0.0016) and distal segments of the antiseptic-coated catheters. Following catheter removal retained activity was demonstrated in benzalkonium chloride catheters which had been in place for up to 12 days. No patients developed adverse reactions to the benzalkonium chloride catheters. The findings demonstrate that the benzalkonium chloride catheter significantly reduced the incidence of catheter-associated colonization.

Thromboresistance Characterization of Extruded Nitric Oxide-Releasing Silicone Catheters

PubMed Central

Amoako, Kagya A.; Archangeli, Christopher; Handa, Hitesh; Major, Terry; Meyerhoff, Mark E.; Annich, Gail M.; Bartlett, Robert H.

2013-01-01

Intravascular catheters used in clinical practice can activate platelets, leading to thrombus formation and stagnation of blood flow. Nitric oxide (NO)-releasing polymers have been shown previously to reduce clot formation on a number of blood contacting devices. In this work, trilaminar NO-releasing silicone catheters were fabricated and tested for their thrombogenicity. All catheters had specifications of L = 6 cm, inner diameter = 21 gauge (0.0723 cm), outer diameter = 12 gauge (0.2052 cm), and NO-releasing layer thickness = 200 ± 11 μm. Control and NO-releasing catheters were characterized in vitro for their NO flux and NO release duration by gas phase chemiluminescence measurements. The catheters were then implanted in the right and left internal jugular veins of (N = 6 and average weight = 3 kg) adult male rabbits for 4 hours thrombogenicity testing. Platelet counts and function, methemoglobin (metHb), hemoglobin (Hb), and white cell counts and functional time (defined as patency time of catheter) were monitored as measured outcomes. Nitric oxide-releasing catheters (N = 6) maintained an average flux above (2 ± 0.5) × 10−10 mol/min/cm2 for more than 24 hours, whereas controls showed no NO release. Methemoglobin, Hb, white cell, and platelet counts and platelet function at 4 hours were not significantly different from baseline (α = 0.05). However, clots on controls were visibly larger and prevented blood draws at a significantly (p < 0.05) earlier time (2.3 ± 0.7 hours) into the experiment, whereas all NO-releasing catheters survived the entire 4 hours test period. Results indicate that catheter NO flux levels attenuated thrombus formation in a short-term animal model. PMID:22395119

Does cranberry have a role in catheter-associated urinary tract infections?

PubMed Central

Thomas, Dominique; Rutman, Matthew; Cooper, Kimberly; Abrams, Andrew; Finkelstein, Julia; Chughtai, Bilal

2017-01-01

Introduction Catheter-associated urinary tract infections (CA-UTIs) are a prevalent and costly condition, with very few therapeutic options. We sought to evaluate the efficacy of an oral cranberry supplement on CA-UTIs over a six-month period. Methods Subjects with long-term indwelling catheters and recurrent symptomatic CA-UTIs were enrolled to take a once-daily oral cranberry supplement with 36 mg of the active ingredient proanthocyanidin (PACs). Primary outcome was reducing the number of symptomatic CA-UTIs. This was defined by ≥103 (cfu)/mL of ≥1 bacterial species in a single catheter urine specimen and signs and symptoms compatible with CA-UTI. Secondary outcomes included bacterial counts and resistance patterns to antibiotics. Results Thirty-four patients were enrolled in the trial; 22 patients (mean age 77.22 years, 77.27% were men) completed the study. Cranberry was effective in reducing the number of symptomatic CA-UTIs in all patients (n=22). Resistance to antibiotics was reduced by 28%. Furthermore, colony counts were reduced by 58.65%. No subjects had adverse events while taking cranberry. Conclusions The cranberry supplement reduced the number of symptomatic CA-UTIs, antibiotic resistances, and major causative organisms in this cohort. Larger, placebo-controlled studies are needed to further define the role of cranberry in CA-UTIs. PMID:29072566

[Project work: formation of health-care personnel for self-care of tunnelled central venous catheters in hemodialysis patients of the territory].

PubMed

Morale, Walter; Patanè, D; Incardona, C; Seminara, G; Malfa, P; L'Anfusa, G; Calcara, G; Bisceglie, P; Puliatti, D; Di Landro, D

2013-01-01

Scientific data from current literature demonstrate an incidence of bacteraemia due to tunnelled central venous catheter (tCVC) use accounting for 1.6 / 1000 days per tCVC, with a range of 1.5 to 1.8. In Sicily no data on the incidence of tCVC- related bacteraemia are available. In our hospital, tCVC infection occurs 2.4 times in 1000 days during CVC use. A retrospective analysis carried out from 2006 to 2012 was performed on 650 patients with tunnelled catheters. Of the subjects who received tCVC in our hospital, 90% were destined to undergo haemodialysis in a private health care environment outside our hospital. In order to improve the aforementioned infection outcome, we planned and implemented a specific work project. The work project (WP) was subdivided into two steps: 1) The first step was further subdivided into two sub-phases. The first was principally concerned with the implementation of educational courses, conducted directly on the ward and aimed at the implementation of meticulous nursing regimes for the care of tCVC by our health care nurse. The courses were entitled Management of Vascular Access: from doing - to teaching to do!. These educational courses were organized by the Nephrology Department, which takes care of the management and handling of the major complications of tCVCs for the maintenance of haemodialysis. After this first step, the nurses who had participated became the promoters of the second part of the course, which concerned the development of know-how within an outpatient clinic, which deals exclusively with the nursing management of tCVCs. 2) The title of the second phase was Therapeutic Education: self-Care and understanding and managing your venous access at home. The aim of this step was the integration of correct in-hospital care with that available in outsourced private institutions, via the involvement of the patient in the management of their own central venous access. During our training project, a more detailed analysis of

Long-term associative learning predicts verbal short-term memory performance.

PubMed

Jones, Gary; Macken, Bill

2018-02-01

Studies using tests such as digit span and nonword repetition have implicated short-term memory across a range of developmental domains. Such tests ostensibly assess specialized processes for the short-term manipulation and maintenance of information that are often argued to enable long-term learning. However, there is considerable evidence for an influence of long-term linguistic learning on performance in short-term memory tasks that brings into question the role of a specialized short-term memory system separate from long-term knowledge. Using natural language corpora, we show experimentally and computationally that performance on three widely used measures of short-term memory (digit span, nonword repetition, and sentence recall) can be predicted from simple associative learning operating on the linguistic environment to which a typical child may have been exposed. The findings support the broad view that short-term verbal memory performance reflects the application of long-term language knowledge to the experimental setting.

Asthma Medicines: Long-Term Control

MedlinePlus

... Size Email Print Share Asthma Medicines: Long-term Control Page Content Article Body Corticosteroids Synthetic versions of ... form, they are used exclusively for long-term control; they are not very effective for acute symptoms. ...

Heat transfer analysis of catheters used for localized tissue cooling to attenuate reperfusion injury.

PubMed

Merrill, Thomas L; Mitchell, Jennifer E; Merrill, Denise R

2016-08-01

Recent revascularization success for ischemic stroke patients using stentrievers has created a new opportunity for therapeutic hypothermia. By using short term localized tissue cooling interventional catheters can be used to reduce reperfusion injury and improve neurological outcomes. Using experimental testing and a well-established heat exchanger design approach, the ɛ-NTU method, this paper examines the cooling performance of commercially available catheters as function of four practical parameters: (1) infusion flow rate, (2) catheter location in the body, (3) catheter configuration and design, and (4) cooling approach. While saline batch cooling outperformed closed-loop autologous blood cooling at all equivalent flow rates in terms of lower delivered temperatures and cooling capacity, hemodilution, systemic and local, remains a concern. For clinicians and engineers this paper provides insights for the selection, design, and operation of commercially available catheters used for localized tissue cooling. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

Extravasation of the contrast media during voiding cystourethrography in a long-term spinal cord injury patient.

PubMed

Kovindha, A; Sivasomboon, C; Ovatakanont, P

2005-07-01

To present complications and pitfalls in voiding cystourethrography (VCUG) and introduce a guideline for performing VCUG in a long-term spinal cord injury (SCI) patient with neurogenic bladder dysfunction (NBD) and contracted bladder. A case report. Maharaj Nakorn Chiang Mai Hospital, Chiang Mai, Thailand. We describe a chronic C(5) tetraplegic man with NBD and contracted bladder, who developed autonomic dysreflexia (AD), gross hematuria and extravasation of contrast median during VCUG. A foley catheter was retained after VCUG. AD was resolved and urine cleared after a week of continuous bladder irrigation. VCUG should be performed with caution in a long-term SCI patient with NBD and contracted bladder. Forceful pushing of the contrast media by the hand-injection method caused abrupt distention of the contracted bladder, damaged bladder mucosa and aggrevated AD. We suggest a guideline as follows: report bladder capacity and AD, if present, in an X-ray requisition form; use the gravity-drip method, stop the drip and drain the contrast media if a sudden headache and rising of blood pressure (BP) develop; observe urine colour, and report if bleeding or AD occurs.

Access technique and its problems in parenteral nutrition – Guidelines on Parenteral Nutrition, Chapter 9

PubMed Central

Jauch, K. W.; Schregel, W.; Stanga, Z.; Bischoff, S. C.; Braß, P.; Hartl, W.; Muehlebach, S.; Pscheidl, E.; Thul, P.; Volk, O.

2009-01-01

Catheter type, access technique, and the catheter position should be selected considering to the anticipated duration of PN aiming at the lowest complication risks (infectious and non-infectious). Long-term (>7–10 days) parenteral nutrition (PN) requires central venous access whereas for PN <3 weeks percutaneously inserted catheters and for PN >3 weeks subcutaneous tunnelled catheters or port systems are appropriate. CVC (central venous catheter) should be flushed with isotonic NaCl solution before and after PN application and during CVC occlusions. Strict indications are required for central venous access placement and the catheter should be removed as soon as possible if not required any more. Blood samples should not to be taken from the CVC. If catheter infection is suspected, peripheral blood-culture samples and culture samples from each catheter lumen should be taken simultaneously. Removal of the CVC should be carried out immediately if there are pronounced signs of local infection at the insertion site and/or clinical suspicion of catheter-induced sepsis. In case PN is indicated for a short period (max. 7–10 days), a peripheral venous access can be used if no hyperosmolar solutions (>800 mosm/L) or solutions with a high titration acidity or alkalinity are used. A peripheral venous catheter (PVC) can remain in situ for as long as it is clinically required unless there are signs of inflammation at the insertion site. PMID:20049083

Inappropriate use of urinary catheters in patients admitted to medical wards in a university hospital.

PubMed

Fernández-Ruiz, Mario; Calvo, Beatriz; Vara, Rebeca; Villar, Rocío N; Aguado, José María

2013-10-01

The prevalence and predisposing factors were determined for inappropriate urinary catheterization (UC) among inpatients in medical wards. A cross-sectional study was conducted including all patients aged ≥ 18 years admitted to medical wards in a 1300-bed tertiary-care centre, and who had a urinary catheter in place on the day of the survey. Of 380 patients observed, 46 (12.1%) had a urinary catheter in place. Twelve of them (26.1%) were inappropriately catheterized. The most common indication for inappropriate UC was urine output monitoring in a cooperative, non-critically ill patient. Inappropriateness was associated with increased age, poor functional status, urinary incontinence, dementia, and admission from a long-term care facility. Further educational efforts should be focused on improving catheterization prescribing practices by physicians. Copyright © 2012 Elsevier España, S.L. All rights reserved.

Long-term experience and outcomes of robotic assisted laparoscopic pyeloplasty in children and young adults.

PubMed

Minnillo, Brian J; Cruz, Jose A S; Sayao, Rogerio H; Passerotti, Carlo C; Houck, Constance S; Meier, Petra M; Borer, Joseph G; Diamond, David A; Retik, Alan B; Nguyen, Hiep T

2011-04-01

Laparoscopic pyeloplasty is one of the more common robotic assisted procedures performed in children. However, data regarding long-term experience and clinical outcomes for this procedure are limited. We evaluated the long-term outcomes in a large series of patients undergoing robotic assisted laparoscopic pyeloplasty at a teaching institution, and the effect of a collaborative program between the robotic surgeons, surgical nurses and anesthesiologists on overall operative time. We retrospectively reviewed 155 patients who underwent robotic assisted laparoscopic pyeloplasty between 2002 and 2009. Operative data, including surgical approach, type of procedure, total and specific operative times and placement of ureteral stents, were determined. Postoperative outcome measurements, including duration of hospital stay, duration of Foley catheter drainage, radiological findings and any subsequent complications, were assessed. Mean operative time and length of hospitalization decreased significantly by the end of the study. At a mean followup of 31.7 months the primary success rate was 96% (hydronephrosis was improved in 85% of patients and stable in 11%). The complication rate was 11%, and recurrent obstruction requiring redo robotic assisted laparoscopic pyeloplasty or open pyeloplasty developed in 3% of patients. Success rate and complication rate were unchanged during the study period. This study confirms that even within the confines of a pediatric urology training program successful collaboration between robotic surgeons, surgical nurses and anesthesiologists can lead to shorter operative times and hospital stays. Long-term surgical success and complication rates were comparable to open surgery. Copyright © 2011 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Reforming long-term care financing through insurance

PubMed Central

Meiners, Mark R.

1988-01-01

Until recently, insurance for long-term care was not viewed as feasible. This perception has changed dramatically in the past few years. Several models of long-term care insurance have begun to be tested. Although the application of insurance principles to long-term care is still new, the emergence of private market interest in developing long-term care insurance has been a catalyst to renewed public-policy support for reforming the way we pay for long-term care. States, in particular, have become interested in developing public-private partnerships to support the emergence of long-term care insurance that could help relieve the mounting pressure on Medicaid budgets. PMID:10312962

Catheter ablation in patients with persistent atrial fibrillation

PubMed Central

Kirchhof, Paulus; Calkins, Hugh

2017-01-01

Catheter ablation is increasingly offered to patients who suffer from symptoms due to atrial fibrillation (AF), based on a growing body of evidence illustrating its efficacy compared with antiarrhythmic drug therapy. Approximately one-third of AF ablation procedures are currently performed in patients with persistent or long-standing persistent AF. Here, we review the available information to guide catheter ablation in these more chronic forms of AF. We identify the following principles: Our clinical ability to discriminate paroxysmal and persistent AF is limited. Pulmonary vein isolation is a reasonable and effective first approach for catheter ablation of persistent AF. Other ablation strategies are being developed and need to be properly evaluated in controlled, multicentre trials. Treatment of concomitant conditions promoting recurrent AF by life style interventions and medical therapy should be a routine adjunct to catheter ablation of persistent AF. Early rhythm control therapy has a biological rationale and trials evaluating its value are underway. There is a clear need to generate more evidence for the best approach to ablation of persistent AF beyond pulmonary vein isolation in the form of adequately powered controlled multi-centre trials. PMID:27389907

Use of peripherally inserted central catheters as an alternative to central catheters in neurocritical care units.

PubMed

DeLemos, Christi; Abi-Nader, Judy; Akins, Paul T

2011-04-01

Patients in neurological critical care units often have lengthy stays that require extended vascular access and invasive hemodynamic monitoring. The traditional approach for these patients has relied heavily on central venous and pulmonary artery catheters. The aim of this study was to evaluate peripherally inserted central catheters as an alternative to central venous catheters in neurocritical care settings. Data on 35 patients who had peripherally inserted central catheters rather than central venous or pulmonary artery catheters for intravascular access and monitoring were collected from a prospective registry of neurological critical care admissions. These data were cross-referenced with information from hospital-based data registries for peripherally inserted central catheters and subarachnoid hemorrhage. Complete data were available on 33 patients with Hunt-Hess grade IV-V aneurysmal subarachnoid hemorrhage. Catheters remained in place a total of 649 days (mean, 19 days; range, 4-64 days). One patient (3%) had deep vein thrombosis in an upper extremity. In 2 patients, central venous pressure measured with a peripherally inserted catheter was higher than pressure measured concurrently with a central venous catheter. None of the 33 patients had a central catheter bloodstream infection or persistent insertion-related complications. CONCLUSIONS Use of peripherally inserted central catheters rather than central venous catheters or pulmonary artery catheters in the neurocritical care unit reduced procedural and infection risk without compromising patient management.

Management training in long-term care.

PubMed

Evashwick, Connie

2002-01-01

The education of health care administrators faces its most dramatic change since the inception of the field. Recent discussions at the national level call for major overhaul of curricula and teaching modalities, including moving education to position students for evidence-based practice. This paper presents recommendations for incorporating training about chronic and long-term care into health care management curricula. It asserts that all health care management students should have a basic knowledge of the fundamental policy, operating, and financing principles of long-term care. The majority of people using the health care delivery system today, and increasingly in the future, suffer from chronic conditions. Long-term care services, although less expansive in structure, far outnumber acute care services and health plans. They will grow in the future to meet the portending demand. To maximize job opportunities and to optimize performance in any job, health care administrators need to know about the long-term care delivery system. This paper delineates critical topics pertaining to long-term care, organized according to 11 fundamental management areas in which the field is developing core competencies. The contents were derived from a year-long process of asking stakeholders in the various facets of long-term care what topics they thought were essential for administrators to know. The topics delineated in this document represent the consensus about essential knowledge that all health care administrators should have about long-term care, whether specializing in long-term care or following a more general management career. The education of health care administrators faces its most dramatic change since the inception ofthe field. Recent discussions at the national level call for major overhaul of curricula and teaching modalities, including moving education to position students to perform according to evidence-based practice. It is thus timely to consider content, as

Root Causes of Field Emitters in SRF Cavities Placed in CEBAF Tunnel

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

Geng, Rongli

It has been suspected that appearance of new field emitters can occur in SRF cavities after their placement in accelerator tunnel for long term beam operation. This apparently has been the case for CEBAF. However, no physical evidence has been shown in the past. In this contribution, we will report on the recent results concerning the root cause of field emitters in SRF cavities placed in CEBAF tunnel. We will discuss these results in the context of high-reliability and low-cryogenic-loss operation of CEBAF.

A Metaproteomics Approach to Elucidate Host and Pathogen Protein Expression during Catheter-Associated Urinary Tract Infections (CAUTIs)

PubMed Central

Lassek, Christian; Burghartz, Melanie; Chaves-Moreno, Diego; Otto, Andreas; Hentschker, Christian; Fuchs, Stephan; Bernhardt, Jörg; Jauregui, Ruy; Neubauer, Rüdiger; Becher, Dörte; Pieper, Dietmar H.; Jahn, Martina; Jahn, Dieter; Riedel, Katharina

2015-01-01

Long-term catheterization inevitably leads to a catheter-associated bacteriuria caused by multispecies bacterial biofilms growing on and in the catheters. The overall goal of the presented study was (1) to unravel bacterial community structure and function of such a uropathogenic biofilm and (2) to elucidate the interplay between bacterial virulence and the human immune system within the urine. To this end, a metaproteomics approach combined with in vitro proteomics analyses was employed to investigate both, the pro- and eukaryotic protein inventory. Our proteome analyses demonstrated that the biofilm of the investigated catheter is dominated by three bacterial species, that is, Pseudomonas aeruginosa, Morganella morganii, and Bacteroides sp., and identified iron limitation as one of the major challenges in the bladder environment. In vitro proteome analysis of P. aeruginosa and M. morganii isolated from the biofilm revealed that these opportunistic pathogens are able to overcome iron restriction via the production of siderophores and high expression of corresponding receptors. Notably, a comparison of in vivo and in vitro protein profiles of P. aeruginosa and M. morganii also indicated that the bacteria employ different strategies to adapt to the urinary tract. Although P. aeruginosa seems to express secreted and surface-exposed proteases to escape the human innate immune system and metabolizes amino acids, M. morganii is able to take up sugars and to degrade urea. Most interestingly, a comparison of urine protein profiles of three long-term catheterized patients and three healthy control persons demonstrated the elevated level of proteins associated with neutrophils, macrophages, and the complement system in the patient's urine, which might point to a specific activation of the innate immune system in response to biofilm-associated urinary tract infections. We thus hypothesize that the often asymptomatic nature of catheter-associated urinary tract infections

A metaproteomics approach to elucidate host and pathogen protein expression during catheter-associated urinary tract infections (CAUTIs).

PubMed

Lassek, Christian; Burghartz, Melanie; Chaves-Moreno, Diego; Otto, Andreas; Hentschker, Christian; Fuchs, Stephan; Bernhardt, Jörg; Jauregui, Ruy; Neubauer, Rüdiger; Becher, Dörte; Pieper, Dietmar H; Jahn, Martina; Jahn, Dieter; Riedel, Katharina

2015-04-01

Long-term catheterization inevitably leads to a catheter-associated bacteriuria caused by multispecies bacterial biofilms growing on and in the catheters. The overall goal of the presented study was (1) to unravel bacterial community structure and function of such a uropathogenic biofilm and (2) to elucidate the interplay between bacterial virulence and the human immune system within the urine. To this end, a metaproteomics approach combined with in vitro proteomics analyses was employed to investigate both, the pro- and eukaryotic protein inventory. Our proteome analyses demonstrated that the biofilm of the investigated catheter is dominated by three bacterial species, that is, Pseudomonas aeruginosa, Morganella morganii, and Bacteroides sp., and identified iron limitation as one of the major challenges in the bladder environment. In vitro proteome analysis of P. aeruginosa and M. morganii isolated from the biofilm revealed that these opportunistic pathogens are able to overcome iron restriction via the production of siderophores and high expression of corresponding receptors. Notably, a comparison of in vivo and in vitro protein profiles of P. aeruginosa and M. morganii also indicated that the bacteria employ different strategies to adapt to the urinary tract. Although P. aeruginosa seems to express secreted and surface-exposed proteases to escape the human innate immune system and metabolizes amino acids, M. morganii is able to take up sugars and to degrade urea. Most interestingly, a comparison of urine protein profiles of three long-term catheterized patients and three healthy control persons demonstrated the elevated level of proteins associated with neutrophils, macrophages, and the complement system in the patient's urine, which might point to a specific activation of the innate immune system in response to biofilm-associated urinary tract infections. We thus hypothesize that the often asymptomatic nature of catheter-associated urinary tract infections

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

Prophylactic antibiotics for preventing early Gram-positive central venous catheter infections in oncology patients, a Cochrane systematic review.

PubMed

van de Wetering, M D; van Woensel, J B M; Kremer, L C M; Caron, H N

2005-05-01

Long-term tunnelled central venous catheters (TCVC) are increasingly used in oncology patients. Infections are a frequent complication of TCVC, mostly caused by Gram-positive bacteria. The objective of this review is to evaluate the efficacy of antibiotics in the prevention of early Gram-positive TCVC infections, in oncology patients. We searched MEDLINE, EMBASE, and the Cochrane Controlled Trials Register up to July 2003. We selected randomised controlled trials (RCT) evaluating prophylactic antibiotics prior to insertion of the TCVC, and the combination of an antibiotic and heparin to flush the TCVC, in paediatric and adult oncology patients. The primary outcome was documented Gram-positive bacteraemia in patients with a TCVC. All trials identified were assessed and the data extracted independently by two reviewers. There were nine trials included. Four trials reported on vancomycin/teicoplanin prior to insertion of the TCVC compared to no antibiotics. There was no reduction in the number of Gram-positive TCVC infections with an Odds ratio of 0.42 (95% confidence interval 0.13-1.31). Five trials studied flushing of the TCVC with a vancomycin/heparin solution compared to heparin flushing only. This method decreased the number of TCVC infections significantly with an Odds ratio of 0.43 (95% CI 0.21-0.87). Flushing the TCVC with a vancomycin/heparin solution reduced the incidence of Gram-positive infections.

Placenta previa and long-term morbidity of the term offspring.

PubMed

Walfisch, Asnat; Beharier, Ofer; Shoham-Vardi, Ilana; Sergienko, Ruslan; Landau, Daniella; Sheiner, Eyal

2016-08-01

The long-term impact of placenta previa on term infants is unknown. We aimed to investigate whether abnormal placentation increases the risk for long-term morbidity of the term offspring. A population-based cohort study compared the incidence of long-term hospitalizations up to the age of 18 due to cardiovascular, endocrine, neurological, hematological, respiratory and urinary morbidity of children born at term in pregnancies diagnosed with placenta previa and those without. Deliveries occurred between the years 1991-2013 in a tertiary medical center. Multiple pregnancies, and fetal congenital malformations were excluded. Kaplan-Meier survival curves were used to compare cumulative morbidity incidence over time. A multivariable generalized estimating equation (GEE) logistic regression model analysis was used to control for confounders and for maternal clusters. During the study period 233,123 term deliveries met the inclusion criteria; 0.2% (n=502) of the children were born to mothers with placenta previa. During the follow-up period, children born to mothers with placenta previa did not have an increased risk for long-term cardiovascular, endocrine, hematological, neurological, respiratory, and urinary morbidity. Term offsprings of mothers diagnosed with placenta previa do not appear to be at an increased risk for long-term morbidity up to the age of 18. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Snare-assisted anterograde balloon mitral and aortic valvotomy using Inoue balloon catheter.

PubMed

Krishnan, Mangalath N; Syamkumar, M D; Sajeev, C G; Venugopal, K; Johnson, Francis; Vinaykumar, D; Velayudhan, C C; Jayakumar, T G

2007-01-02

We performed concurrent antegrade mitral and aortic valvotomy using Inoue dilatation catheter in 3 cases of combined rheumatic mitral and aortic stenosis. Following mitral valvotomy by standard procedure, aortic valve was crossed with the help of a floatation catheter. Stiff long length guide wire was fixed in descending aorta using a snare. Inoue catheter was threaded over the wire across the aortic valve and aortic valvotomy completed. Mitral valve area increased from mean 1 cm2 to 2 cm2; aortic gradient dropped from mean of 97 mm to 36 mm. Concurrent anterograde balloon mitral and aortic valvotomy may be effective and safe.

Consider long-term care as service alternative.

PubMed

Loria, L S

1987-04-01

The increasing demand for elderly care services, pressures on inpatient average length of stay and payment levels, and potential financial rewards from providing additional services, makes long-term care look attractive to hospitals. Long-term care, however, is not for every hospital. Before deciding to establish long-term care services, management should examine how the service fits within the hospital's strategic plan. The action plan below provides guidance in evaluating a decision to use hospital facilities for long-term care. Examine how long-term care services fit within the hospital's strategic plan. Study area demographics and competitors to assess the need and supply of long-term care services. Survey the medical staff, consumers and payers to determine attitudes, perceptions and interests regarding long-term care services. Develop a facility plan that identifies areas of excess capacity that can be most easily converted into long-term care with minimal effects on hospital operations. Prepare a financial feasibility analysis of the contribution margin and return on investment attributable to long-term care services. Include an impact analysis on hospital operations. Establish a management task force to develop a detailed implementation plan including assigned individual responsibilities and related timetable. Develop an effective marketing plan designed to generate increased patient market share.

PRE-INOCULATION OF URINARY CATHETERS WITH ESCHERICHIA COLI 83972 INHIBITS CATHETER COLONIZATION BY ENTEROCOCCUS FAECALIS

PubMed Central

TRAUTNER, BARBARA W.; DAROUICHE, RABIH O.; HULL, RICHARD A.; HULL, SHEILA; THORNBY, JOHN I.

2010-01-01

Purpose The capacity of a preexisting coating of Escherichia coli 83972 to reduce catheter colonization by Enterococcus faecalis 210 was investigated. Enterococcus was chosen for these trials since it is a common urinary pathogen in patients with an indwelling urinary catheter. Materials and Methods Each experiment tested 3 growth conditions. Group 1 or E. coli plus Enterococcus catheters were exposed to E. coli 83972 for 24 hours and then to Enterococcus for 30 minutes. Group 2 or E. coli alone catheters were incubated in E. coli for 24 hours and then in sterile broth for 30 minutes. Group 3 or Enterococcus alone catheters did not undergo the initial incubation with E. coli before the 30-minute incubation with Enterococcus: All catheters were then incubated in sterile human urine for 24 hours. Catheters were washed with saline and cut into 5, 1 cm. segments. Each segment was sonicated and the sonication fluid was diluted and plated. The results of each of the 5 segments were averaged and the set of experiments was repeated 7 times. Results A preexisting coating of E. coli 83972 reduced catheter colonization by E. faecalis 210 more than 10-fold. Enterococcus alone catheters had a median of 9.7 × 105 enterococci per cm., whereas E. coli plus Enterococcus catheters had a median of 0.38 × 105 enterococci per cm. (p = 0.016). Conclusions Pre-inoculating urinary catheters with E. coli 83972 significantly impedes catheter colonization by Enterococcus: These promising in vitro results prompt the clinical investigation of this particular application of bacterial interference. PMID:11743359

Long-term data archiving

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

Moore, David Steven

2009-01-01

Long term data archiving has much value for chemists, not only to retain access to research and product development records, but also to enable new developments and new discoveries. There are some recent regulatory requirements (e.g., FDA 21 CFR Part 11), but good science and good business both benefit regardless. A particular example of the benefits of and need for long term data archiving is the management of data from spectroscopic laboratory instruments. The sheer amount of spectroscopic data is increasing at a scary rate, and the pressures to archive come from the expense to create the data (or recreatemore » it if it is lost) as well as its high information content. The goal of long-term data archiving is to save and organize instrument data files as well as any needed meta data (such as sample ID, LIMS information, operator, date, time, instrument conditions, sample type, excitation details, environmental parameters, etc.). This editorial explores the issues involved in long-term data archiving using the example of Raman spectral databases. There are at present several such databases, including common data format libraries and proprietary libraries. However, such databases and libraries should ultimately satisfy stringent criteria for long term data archiving, including readability for long times into the future, robustness to changes in computer hardware and operating systems, and use of public domain data formats. The latter criterion implies the data format should be platform independent and the tools to create the data format should be easily and publicly obtainable or developable. Several examples of attempts at spectral libraries exist, such as the ASTM ANDI format, and the JCAMP-DX format. On the other hand, proprietary library spectra can be exchanged and manipulated using proprietary tools. As the above examples have deficiencies according to the three long term data archiving criteria, Extensible Markup Language (XML; a product of the World Wide

Long-Term Control Medications for Lung Diseases

MedlinePlus

... Asthma Medications Long-Term Control Medications Long-Term Control Medications Make an Appointment Ask a Question Refer Patient Long-term control medications are taken daily to control and prevent ...

A simple device for exteriorizing chronically implanted catheters in dogs.

PubMed

Butterfield, J L; Decker, G E

1984-04-01

A device, consisting of a round base and cap made of polytetrafluoroethylene, was made to exteriorize and protect chronically implanted arterial and venous catheters in conscious dogs. In experiments lasting as long as 9 months, the subcutaneously implanted button-like appliance did not cause tissue reactions and was well tolerated by 98% of a group of 200 dogs. Being maintenance-free, having the capacity to exteriorize several catheter or wire outputs, and needing no protective harness were advantages of the device.

Linear ablation of right atrial free wall flutter: demonstration of bidirectional conduction block as an endpoint associated with long-term success.

PubMed

Snowdon, Richard L; Balasubramaniam, Richard; Teh, Andrew W; Haqqani, Haris M; Medi, Caroline; Rosso, Raphael; Vohra, Jitendra K; Kistler, Peter M; Morton, Joseph B; Sparks, Paul B; Kalman, Jonathan M

2010-05-01

Ablation for atypical atrial flutter (AFL) is often performed during tachycardia, with termination or noninducibility of AFL as the endpoint. Termination alone is, however, an inadequate endpoint for typical AFL ablation, where incomplete isthmus block leads to high recurrence rates. We assessed conduction block across a low lateral right atrial (RA) ablation line (LRA) from free wall scar to the inferior vena cava (IVC) or tricuspid annulus in 11 consecutive patients with atypical RA free wall flutter. LRA block was assessed following termination of AFL, by pacing from the ablation catheter in the low lateral RA posterior to the ablation line and recording the sequence and timing of activation anterior to the line with a duodecapole catheter, and vice versa for bidirectional block. LRA block resulted in a high to low activation pattern on the halo and a mean conduction time of 201 +/- 48 ms to distal halo. LRA conduction block was present in only 2 out of 6 patients after termination of AFL by ablation. Ablation was performed during sinus rhythm (SR) in 9 patients to achieve LRA conduction block. No recurrence of AFL was observed at long-term follow-up (22 +/- 12 months); 3 patients developed AF. Termination of right free wall flutter is often associated with persistent LRA conduction and additional radiofrequency ablation (RFA) in SR is usually required. Low RA pacing may be used to assess LRA conduction block and offers a robust endpoint for atypical RA free wall flutter ablation, which results in a high long-term cure rate.

Reforming Long-Term Care Funding in Alberta.

PubMed

Crump, R Trafford; Repin, Nadya; Sutherland, Jason M

2015-01-01

Like many provinces across Canada, Alberta is facing growing demand for long-term care. Issues with the mixed funding model used to pay long-term care providers had Alberta Health Services concerned that it was not efficiently meeting the demand for long-term care. Consequently, in 2010, Alberta Health Services introduced the patient/care-based funding (PCBF) model. PCBF is similar to activity-based funding in that it directly ties the complexity and care needs of long-term care residents to the payment received by long-term care providers. This review describes PCBF and discusses some of its strengths and weaknesses. In doing so, this review is intended to inform other provinces faced with similar long-term care challenges and contemplating their own funding reforms.

Railway tunnels in Europe and North America

DOT National Transportation Integrated Search

2002-05-01

This list of railway tunnels (longer than 1, 000 m) was compiled by the secretariat from various national and international sources. The list is intended to serve as a reference inventory for a long railway tunnels in Europe and North America. Tunnel...

[Central venous catheter-related infections in critically ill patients].

PubMed

Diener, J R; Coutinho, M S; Zoccoli, C M

1996-01-01

To determine incidence rate, etiology and risk factors for central venous catheter (CVC)-related infections in critically-ill patients, a prospective cohort study was conducted in the general Intensive Care Unit (ICU) of a 212 bed Hospital in Florianópolis, Brazil. Patients admitted to ICU between May 1993 and February 1994, exposed to short-term CVC, were included in the study. Quantitative skin culture at CVC insertion site, semi-quantitative CVC tip culture, quantitative hub culture, and peripheral blood-culture were done. Results were submitted to univariate and multivariate analysis. Fifty-seven catheterization periods were analysed in 51 patients. The incidence rate was 21.1% (33.1 per 1,000 catheter-days) for local infection, and 8.7% (14.1 per 1,000 catheter-days) for catheter-associated bacteremia. The skin at the insertion site was colonized in 32.7% and the hub in 29.1% of the patients respectively. Potential sources of infection were the skin in 41.2% of the cases, the hub in 29.4%, remote site in 5.9% and unknown in 23.5%. The hub was implicated in 60% of the catheter-associated bacteremias. Coagulase-negative staphylococci were the main isolates. Another intravascular device and purulence at the insertion site were independently associated with local infection. Insertion at internal jugular site and hub colonization were independently associated with bacteremia. Catheter-associated bacteremia is a major complication of central venous catheterization in critically-ill patients. Internal jugular insertion and CVC hub colonization are important risk factors for significant catheter-related infections.

Treatment of cytomegalovirus retinitis with intravitreal ganciclovir. Long-term results.

PubMed

Cantrill, H L; Henry, K; Melroe, N H; Knobloch, W H; Ramsay, R C; Balfour, H H

1989-03-01

Long-term management of cytomegalovirus (CMV) retinitis by intravitreal injection of ganciclovir was evaluated in ten patients with acquired immune deficiency syndrome (AIDS). Patients were unable to tolerate systemic ganciclovir because of severe neutropenia (8 cases), catheter-induced sepsis (1 case), or the need to continue therapy for human immunodeficiency virus (HIV) with zidovudine (ZDV) (1 case). All patients had a favorable response to initial treatment. Cytomegalovirus retinitis progressed in four fellow eyes in which treatment was deferred. Vision improved or remained stable in all but one eye. Patients were followed for a mean of 4 months and received an average of 16.6 intravitreal injections in each eye. Relapse occurred late in the course while on maintenance treatment in five eyes (33%). There was no evidence of toxicity from repeated intravitreal injections. Treatment was very well tolerated. The only severe complication in a total of 249 injections was a single case of Staphylococcus epidermidis endophthalmitis which responded to intravitreal antibiotic treatment. Intravitreal ganciclovir is an effective alternative to systemic ganciclovir in those patients with severe neutropenia and in those patients who desire to remain on systemic ZDV.

Thrombotic complications and tip position of transjugular chronic dialysis catheter scheduled into superior vena cava

PubMed Central

Li, Whenzheng; Li, Fang; Wang, He; Long, Xueying; Ghimire, Obin; Pei, Yigang; Xiao, Xiangcheng; Ning, Jianping

2017-01-01

Abstract Background: Catheter-related thrombotic complications(TCs) can occur during the long term use of a chronic dialysis catheter (CDC), including fibrin sheath (FS), mural thrombosis (MT), venous thrombosis (VT), and intraluminal clots (IC), which has not been reported with MRI. The aim of our study was to evaluate the determination of catheter tip position (TP) and resolution of TCs in patients with transjugular CDC scheduled into the superior vena cava using high resolution magnetic resonance cholangiopancreatography (HR-MRCP) and T2-weighted imaging (HR-T2WI). Methods: The study protocol was approved by the local Research Ethics Committee. Informed consent was obtained from all patients. In total, 41 consecutively enrolled transjugular CDC patients with suspected catheter dysfunction were scanned with HRMRCP and HR-T2WI. The distance from the top to the tip of the catheter and the presence and nature of catheter TCs were assessed by 2 experienced radiologists. Chest x-ray was taken within 1 to 2 days and CDC was withdrawn within 3 to 10 days from those patients with TCs identified by HR-MRI. Results: A total of 38 subjects successfully underwent HR-MRI, including 13 normal and 25 with TCs (fibrin sheath [FS]: n = 21, mural thrombosis [MT]: n = 7, venous thrombosis [VT]: n = 3, intraluminal clots [IC]: n = 4). There was no significant difference between HR-MRCP and chest x-ray in catheter TP determination (P = .124). Normal catheter appeared as “double eyes” on HR-T2WI and “double tracks” on HR-MRCP. TCs appeared as follows: FS displayed as a “thin ring” (<1mm) around the catheter, MT as patchy hyperintensity and VT as a “thick ring” (>5mm) on HR-T2WI. Unilateral IC appeared as a “single eye” on HR-T2WI and a “single track” on HR-MRCP (n = 3). Bilateral IC appeared as neither “eye” nor “track” (n = 1). Catheter withdrawal confirmed FS (n = 16), MT (n = 6), VT (n = 1), and IC (n = 4

A guideline for adults with an indwelling urinary catheter in different health care Settings - methodological procedures

PubMed

Barbezat, Isabelle; Willener, Rita; Jenni, Giovanna; Hürlimann, Barbara; Geese, Franziska; Spichiger, Elisabeth

2017-07-01

Background: People with an indwelling urinary catheter often suffer from complications and health care professionals are regularly confronted with questions about catheter management. Clinical guidelines are widely accepted to promote evidence-based practice. In the literature, the adaptation of a guideline is described as a valid alternative to the development of a new one. Aim: To translate a guideline for the care for adults with an indwelling urinary catheter in the acute and long term care setting as well as for home care. To adapt the guideline to the Swiss context. Method: In a systematic and pragmatic process, clinical questions were identified, guidelines were searched and evaluated regarding clinical relevance and quality. After each step, the next steps were defined. Results: An English guideline was translated, adapted to the local context and supplemented. The adapted guideline was reviewed by experts, adapted again and approved. After 34 months and an investment of a total of 145 man working days, a guideline for the care for people with an indwelling urinary catheter is available for both institutions. Conclusions: Translation and adaptation of a guideline was a valuable alternative to the development of a new one; nevertheless, the efforts necessary should not be underestimated. For such a project, sufficient professional and methodological resources should be made available to achieve efficient guideline work by a constant team.

Indwelling catheter care

MedlinePlus

... it overnight. You will be shown how to disconnect the bags from the Foley catheter in order ... bags through a separate valve without needing to disconnect the bag from the Foley catheter. Making Sure ...

Long-term absorption of poly-L-lactic Acid interference screws.

PubMed

Barber, F Alan; Dockery, W Dee

2006-08-01

To evaluate the long term in vivo degradation of poly-L-lactic acid (PLLA) interference screws with computed tomography (CT) and radiography as used in patellar tendon autograft anterior cruciate ligament (ACL) reconstruction. A total of 20 patients who had undergone patellar tendon autograft ACL reconstruction fixed with PLLA screws at least 7 years earlier were evaluated by physical examination, radiography, and CT to determine whether PLLA screw reabsorption and bone ingrowth had occurred. This study was granted Institutional Review Board approval. Lysholm, Tegner, Cincinnati, and International Knee Documentation Committee (IKDC) scores were obtained. CT data were measured in Hounsfield units. In all, 15 men and 5 women were evaluated 104 months after surgery (range, 89 to 124 months). CT and radiography demonstrated that the bone plug had fused to the tunnel wall, and that no intact interference screw was left. A parallel, threaded, and corticated screw tract was visible adjacent to the bone plug. No bone ingrowth had occurred at the screw site, although, occasionally, minimal calcification was seen. This was never as dense as cancellous bone, and no trabeculae were ever present. No positive pivot-shift test results were obtained. Lysholm, Tegner, and Cincinnati scores were 83, 5.6, and 75, respectively, at follow-up. Average KT difference was 0.7 mm. PLLA interference screws completely degraded, and the resulting area demonstrated a low Hounsfield count, consistent with soft tissue 7 years after insertion. No significant bone ingrowth occurred at the screw site. Femoral and tibial ACL tunnels were absent of anything but fibrous tissue and usually had a sclerotic cortical lining. PLLA biodegradable ACL screws eventually disappear completely. PLLA material is not replaced by bone. ACL graft tunnels are filled with nonossified material. This study provides a baseline for comparison with other biodegradable interference screws that may encourage bone ingrowth as

Spin-dependent tunneling effects in magnetic tunnel junctions

NASA Astrophysics Data System (ADS)

Gao, Li

2009-03-01

It has long been known that current extracted from magnetic electrodes through ultra thin oxide tunnel barriers is spin polarized. This current gives rise to two important properties: tunneling magnetoresistance (TMR) when the tunnel barrier is sandwiched between two thin magnetic electrodes and, spin momentum transfer, which can be used to manipulate the magnetic state of the magnetic electrodes. In the first part of my talk I show how the structure of thin CoFe layers can be made amorphous by simply sandwiching them between two amorphous layers, one of them the tunnel barrier. No glass forming elements are needed. By slightly changing the thickness of these layers or by heating them above their glass transition temperature they become crystalline. Surprisingly, the TMR of the amorphous structure is significantly higher than of its crystalline counterpart. The tunneling anisotropic magnetoresistance, which has complex voltage dependence, is also discussed. In the second part of my talk I discuss the microwave emission spectrum from magnetic tunnel junctions induced by spin torque from spin polarized dc current passed through the device. We show that the spectrum is very sensitive to small variations in device structures, even in those devices which exhibit similarly high TMR (˜120%) and which have similar resistance-area products (˜4-10 φμm^2). We speculate that these variations are due to non-uniform spatial magnetic excitation arising from inhomogeneous current flow through the tunnel barrier. [In collaboration with Xin Jiang, M. Hayashi, Rai Moriya, Brian Hughes, Teya Topuria, Phil Rice, and Stuart S.P. Parkin

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

Catheterless Long-Term Ambulatory Urodynamic Measurement Using a Novel Three-Device System

PubMed Central

Wille, Sebastian; Schumacher, Pauline; Paas, Jenny; Tenholte, Dirk; Eminaga, Okyaz; Müller, Ute; Muthen, Noemi; Mehner, Jan; Cornely, Oliver; Engelmann, Udo

2014-01-01

Aims Long-term urodynamics are required because bladder-emptying disorders are often not clearly revealed by conventional urodynamics. Patients with severe clinical overactive bladder symptoms, for instance, often show normal results. This may be due to the short evaluation time and psychological factors that complicate conventional urodynamics. This study aimed to develop an ambulatory three-component urodynamic measurement system that is easy to operate, registers urodynamic parameters for several days, and has no negative impact on the patient. Methods We developed an intravesical capsule combined with a hand-held device to register voiding desire and micturition, and an alarm pad device that detects urine loss. Recently, the intravesical capsule and its proven function were detailed in the literature. Here, we present detailed in vitro results using a female bladder model. The flexible capsule was C-shaped to minimize the risk of expulsion from the bladder during micturition. Results of biocompatibility evaluation of the intravesical capsule, which is called Wille Capsule (WiCa) are described. Results The WiCa with an oval nose and a maximum outer diameter of 5.5 mm was easily inserted through a 25-French cystoscope. Removing the WiCa by grasping the nose using the female model with bladder was easily conducted. Expulsion of the WiCa during voiding was avoided through a novel C-shaped device design. Based on in vitro cytotoxicity studies, the capsule is a promising and safe device. Conclusion Our novel system is an innovative minimally-invasive tool for accurate long-term urodynamic measurement, and does not require inserting a transurethral catheter. PMID:24840482

The Long-Term Budget Outlook

DTIC Science & Technology

2005-12-01

Revenues Under CBO’s Long-Term Budget Scenarios 56A-8. Real Gross Domestic Product Under CBO’s Long-Term Budget Scenarios 57A-9. Total Surplus or...scenarios suggest that total federal spending for Medicare and Medicaid in 2050 could range anywhere from 7 percent of gross domestic product (GDP)—a...see the Congressional Budget Office’s glossary of budgetary and economic terms, available at www.cbo.gov. 2. The future path of productivity growth

Choosing the appropriate side for subcutaneous port catheter placement in patients with mastectomy: ipsilateral or contralateral?

PubMed

Nas, Omer Fatih; Hacikurt, Kadir; Kaya, Ahmet; Dogan, Nurullah; Sanal, Bekir; Ozkaya, Guven; Dundar, Halit Ziya; Erdogan, Cuneyt

2017-06-01

To evaluate long-term clinical follow-up results of implanting subcutaneous port catheters (SPCs) on ipsilateral or contralateral with mastectomy side in patients with axillary lymph node dissection. A total of 73 patients composed of ipsilateral (34 catheters) and contralateral (39 catheters) groups, with SPCs were included. All patients had lumpectomy or modified radical mastectomy for breast cancer. Ipsilateral and contralateral groups had similar patient characteristics. Five late complications were seen in the ipsilateral group and 2 late complications in the contralateral group. No statistical significant difference was seen between two groups in regard to late complications. Four complications of the ipsilateral group were classified as major group C and 1 as major group D, while 1 complication of the contralateral group was classified as minor group B and 1 as major group C according to Society of Interventional Radiology (SIR) classification. No statistical significant difference was seen between complication rates of two groups in regard to SIR classification. SPC related complications do not differ in regard to ipsilateral or contralateral side selection on mastectomized patients with breast cancer and lymph node dissection. SPCs can be implanted on ipsilateral or contralateral sides of the operation in these patients.

Magnetic resonance imaging compatible remote catheter navigation system with 3 degrees of freedom.

PubMed

Tavallaei, M A; Lavdas, M K; Gelman, D; Drangova, M

2016-08-01

To facilitate MRI-guided catheterization procedures, we present an MRI-compatible remote catheter navigation system that allows remote navigation of steerable catheters with 3 degrees of freedom. The system consists of a user interface (master), a robot (slave), and an ultrasonic motor control servomechanism. The interventionalist applies conventional motions (axial, radial and plunger manipulations) on an input catheter in the master unit; this user input is measured and used by the servomechanism to control a compact catheter manipulating robot, such that it replicates the interventionalist's input motion on the patient catheter. The performance of the system was evaluated in terms of MRI compatibility (SNR and artifact), feasibility of remote navigation under real-time MRI guidance, and motion replication accuracy. Real-time MRI experiments demonstrated that catheter was successfully navigated remotely to desired target references in all 3 degrees of freedom. The system had an absolute value error of [Formula: see text]1 mm in axial catheter motion replication over 30 mm of travel and [Formula: see text] for radial catheter motion replication over [Formula: see text]. The worst case SNR drop was observed to be [Formula: see text]3 %; the robot did not introduce any artifacts in the MR images. An MRI-compatible compact remote catheter navigation system has been developed that allows remote navigation of steerable catheters with 3 degrees of freedom. The proposed system allows for safe and accurate remote catheter navigation, within conventional closed-bore scanners, without degrading MR image quality.

Long-term outcomes after severe shock.

PubMed

Pratt, Cristina M; Hirshberg, Eliotte L; Jones, Jason P; Kuttler, Kathryn G; Lanspa, Michael J; Wilson, Emily L; Hopkins, Ramona O; Brown, Samuel M

2015-02-01

Severe shock is a life-threatening condition with very high short-term mortality. Whether the long-term outcomes among survivors of severe shock are similar to long-term outcomes of other critical illness survivors is unknown. We therefore sought to assess long-term survival and functional outcomes among 90-day survivors of severe shock and determine whether clinical predictors were associated with outcomes. Seventy-six patients who were alive 90 days after severe shock (received ≥1 μg/kg per minute of norepinephrine equivalent) were eligible for the study. We measured 3-year survival and long-term functional outcomes using the Medical Outcomes Study 36-Item Short-Form Health Survey, the EuroQOL 5-D-3L, the Hospital Anxiety and Depression Scale, the Impact of Event Scale-Revised, and an employment instrument. We also assessed the relationship between in-hospital predictors and long-term outcomes. The mean long-term survival was 5.1 years; 82% (62 of 76) of patients survived, of whom 49 were eligible for follow-up. Patients who died were older than patients who survived. Thirty-six patients completed a telephone interview a mean of 5 years after hospital admission. The patients' Physical Functioning scores were below U.S. population norms (P < 0.001), whereas mental health scores were similar to population norms. Nineteen percent of the patients had symptoms of depression, 39% had symptoms of anxiety, and 8% had symptoms of posttraumatic stress disorder. Thirty-six percent were disabled, and 17% were working full-time. Early survivors of severe shock had a high 3-year survival rate. Patients' long-term physical and psychological outcomes were similar to those reported for cohorts of less severely ill intensive care unit survivors. Anxiety and depression were relatively common, but only a few patients had symptoms of posttraumatic stress disorder. This study supports the observation that acute illness severity does not determine long-term outcomes. Even extremely

Safety of a new compact male intermittent catheter: randomized, cross-over, single-blind study in healthy male volunteers.

PubMed

Bagi, Per; Hannibalsen, Jane; Permild, Rikke; Stilling, Sine; Looms, Dagnia K

2011-01-01

A new compact male intermittent catheter was compared with a regular intermittent male catheter in terms of safety and acceptability. In this randomized, single-blind, cross-over study, healthy male volunteers were catheterized twice with a compact catheter and twice with a regular catheter. 28 participants were enrolled. Mean ± SD discomfort (visual analogue scale; primary objective) was 2.25 ± 1.5 and 2.52 ± 1.8 for the compact and regular catheters, respectively (difference -0.27; 95% confidence interval -0.73 to 0.19); there was no significant difference in hematuria (p = 0.54) or discomfort/stinging/pain at first micturition (p = 0.56). During insertion, handling was easier (p = 0.0001) and touching the coating was necessary less often (2.2 vs. 81.3% of catheterizations; p < 0.0001) with the compact catheter; it was preferred by nurses for 20 of 23 participants. No adverse events were reported. Short-term safety of the new compact catheter was at least as good as that of the regular male intermittent catheter and handling was improved. Copyright © 2011 S. Karger AG, Basel.

Determining the best catheter for sonohysterography.

PubMed

Dessole, S; Farina, M; Capobianco, G; Nardelli, G B; Ambrosini, G; Meloni, G B

2001-09-01

To compare the characteristics of six different catheters for performing sonohysterography (SHG) to identify those that offer the best compromise between reliability, tolerability, and cost. Prospective study. University hospital. Six hundred ten women undergoing SHG. We performed SHG with six different types of catheters: Foleycath (Wembley Rubber Products, Sepang, Malaysia), Hysca Hysterosalpingography Catheter (GTA International Medical Devices S.A., La Caleta D.N., Dominican Republic), H/S Catheter Set (Ackrad Laboratories, Cranford, NJ), PBN Balloon Hystero-Salpingography Catheter (PBN Medicals, Stenloese, Denmark), ZUI-2.0 Catheter (Zinnanti Uterine Injection; BEI Medical System International, Gembloux, Belgium), and Goldstein Catheter (Cook, Spencer, IN). We assessed the reliability, the physician's ease of use, the time requested for the insertion of the catheter, the volume of contrast medium used, the tolerability for the patients, and the cost of the catheters. In 568 (93%) correctly performed procedures, no statistically significant differences were found among the catheters. The Foleycath was the most difficult for the physician to use and required significantly more time to position correctly. The Goldstein catheter was the best tolerated by the patients. The Foleycath was the cheapest whereas the PBN Balloon was the most expensive. The choice of the catheter must be targeted to achieving a good balance between tolerability for the patients, efficacy, cost, and the personal preference of the operator.

Short-term Action Intentions Overrule Long-Term Semantic Knowledge

ERIC Educational Resources Information Center

van Elk, M.; van Schie, H.T.; Bekkering, H.

2009-01-01

In the present study, we investigated whether the preparation of an unusual action with an object (e.g. bringing a cup towards the eye) could selectively overrule long-term semantic representations. In the first experiment it was found that unusual action intentions activated short-term semantic goal representations, rather than long-term…

Mechanical Tunneling in Solid Rock

DOT National Transportation Integrated Search

1979-12-01

This report introduces the principles of mchanized tunneling and provides detailed guidelines for practical application. The subject is introduced with a detailed review of technical aspects and terms relating to mchanized tunneling. It discusses the...

Acute urinary retention: which catheter?

PubMed Central

Allardice, J. T.; Standfield, N. J.; Wyatt, A. P.

1988-01-01

There is no scientific data on which is the best method and catheter to use in acute urinary retention in males. We therefore compared the efficiency of a size 12 G latex rubber balloon catheter with a similar calibre but more expensive catheter made of polyvinyl-chloride (PVC). A total of 50 patients was studied and a 100% successful catheterisation rate was recorded at first attempt with both catheters, with no significant complications. The importance of the correct management of acute urinary retention, especially adequate analgesia, is stressed and it is concluded that either catheter is satisfactory. PMID:3207328

Compensation for PKMζ in long-term potentiation and spatial long-term memory in mutant mice.

PubMed

Tsokas, Panayiotis; Hsieh, Changchi; Yao, Yudong; Lesburguères, Edith; Wallace, Emma Jane Claire; Tcherepanov, Andrew; Jothianandan, Desingarao; Hartley, Benjamin Rush; Pan, Ling; Rivard, Bruno; Farese, Robert V; Sajan, Mini P; Bergold, Peter John; Hernández, Alejandro Iván; Cottrell, James E; Shouval, Harel Z; Fenton, André Antonio; Sacktor, Todd Charlton

2016-05-17

PKMζ is a persistently active PKC isoform proposed to maintain late-LTP and long-term memory. But late-LTP and memory are maintained without PKMζ in PKMζ-null mice. Two hypotheses can account for these findings. First, PKMζ is unimportant for LTP or memory. Second, PKMζ is essential for late-LTP and long-term memory in wild-type mice, and PKMζ-null mice recruit compensatory mechanisms. We find that whereas PKMζ persistently increases in LTP maintenance in wild-type mice, PKCι/λ, a gene-product closely related to PKMζ, persistently increases in LTP maintenance in PKMζ-null mice. Using a pharmacogenetic approach, we find PKMζ-antisense in hippocampus blocks late-LTP and spatial long-term memory in wild-type mice, but not in PKMζ-null mice without the target mRNA. Conversely, a PKCι/λ-antagonist disrupts late-LTP and spatial memory in PKMζ-null mice but not in wild-type mice. Thus, whereas PKMζ is essential for wild-type LTP and long-term memory, persistent PKCι/λ activation compensates for PKMζ loss in PKMζ-null mice.

Effect of an Education Presentation On the Knowledge and Awareness of Urinary Tract Infection among Non-Licensed and Licensed Health Care Workers in Long-Term Care Facilities.

PubMed

Freeman-Jobson, Jennifer H; Rogers, Jamie L; Ward-Smith, Peggy

2016-01-01

This article presents the findings of a pre-test, post-test quality improvement project that describes the change in knowledge from prior to and following an evidence-based education presentation. The presentation addressed the clinical symptoms, diagnostic processes, interventions, and responsibilities of licensed and unlicensed health care workers employed in long-term care facilities related to prevention and detection of non-catheter-related urinary tract infections. Results indicate that the education presentation improved knowledge in specific.

Chronic urinary tract infections in patients with spinal cord lesions - biofilm infection with need for long-term antibiotic treatment.

PubMed

Tofte, Nete; Nielsen, Alex C Y; Trøstrup, Hannah; Andersen, Christine B; Von Linstow, Michael; Hansen, Birgitte; Biering-Sørensen, Fin; Høiby, Niels; Moser, Claus

2017-04-01

Patients suffering from spinal cord injuries resulting in complete or incomplete paraplegia or tetraplegia are highly disposed to frequent, recurrent or even chronic urinary tract infections (UTIs). The reason for the increased risk of acquiring UTIs is multifactorial, including reduced sensation of classical UTI symptoms, incomplete bladder emptying, frequent catheterizations or chronic urinary tract catheters. Biofilms in relation to UTIs have been shown both on catheters, on concrements or as intracellular bacterial communities (IBCs). Due to the increased risk of acquiring recurrent or chronic UTIs and frequent antibiotic treatments, patients experience an increased risk of being infected with antibiotic-resistant bacteria like extended-spectrum β-lactamase-producing Escherichia coli or Klebsiella spp., but also bacteria like Pseudomonas aeruginosa inherently resistant to several antibiotics. Diagnosing the UTI can also be challenging, especially distinguishing harmless colonization from pathogenic infection. Based on a previous study showing activation of humoral immune response toward UTI pathogens in patients with spinal cord lesions (SCL), the present mini review is an evaluation of using antibody response as an indicator of chronic biofilm UTI. In addition, we evaluated the effect of long-term treatment with antibiotics in patients with SCLs and chronic UTI, defined by culturing of a uropathogen in the urine and elevated specific precipitating antibodies against the same uropathogen in a blood sample. Elimination of chronic UTI, decrease in specific precipitating antibody values and avoiding selection of new multidrug-resistant (MDR) uropathogens were the primary markers for effect of treatment. The results of this evaluation suggest that the long-term treatment strategy in SCL patients with chronic UTI may be effective; however, randomized prospective results are needed to confirm this. © 2017 APMIS. Published by John Wiley & Sons Ltd.

Echogenic Catheters and Embryo Transfer Standardization.

PubMed

Urbina, Maria Teresa; Benjamin, Isaac; Medina, Randolfo; Lerner, Jorge

2015-05-01

1.To describe the standardization process and protocols of the ET method at our center. 2.To compare the performance of non-echogenic catheters with echogenic catheters during ultrasound-guided ET. Retrospective analysis of 2630 ET performed at UNIFERTES during 1997-2014, to describe standardization process and to compare the percentage of difficult ET between echogenic and non-echogenic catheters. We tested 17 non-echogenic and three echogenic catheters. Many variables were associated with the ease of ET: informed patients, waiting time for the procedure, speculum use, clinical touch, uterine contractions, cervical mucus removal, presence of blood before or after the procedure, full bladder, ultrasound guidance, uterocervical angle, mock transfer, catheter type (soft or hard, echogenic or non-echogenic, with stylet or not), catheter loading technique, duration of embryo loading (time interval since the embryos were removed from the incubator for loading until the catheter is passed to the physician), transfer procedure (time interval from the catheter was handed to the physician until the embryos were discharged in the uterus), catheter tip placement, retained embryos, bed rest after ET, operator´s proficiency. The diversity of catheters used and the percentage of difficult transfers decrease as the use of echogenic catheters increases. This process is necessary to minimize variation, ensure high quality, safe and evidence-based practice, and improve outcomes. To standardize the ET method allowed a quicker and easier transfer. The use of echogenic catheters simplified ET procedures guided by abdominal ultrasound.

Long Josephson tunnel junctions with doubly connected electrodes

NASA Astrophysics Data System (ADS)

Monaco, R.; Mygind, J.; Koshelets, V. P.

2012-03-01

In order to mimic the phase changes in the primordial Big Bang, several cosmological solid-state experiments have been conceived, during the last decade, to investigate the spontaneous symmetry breaking in superconductors and superfluids cooled through their transition temperature. In one of such experiments, the number of magnetic flux quanta spontaneously trapped in a superconducting loop was measured by means of a long Josephson tunnel junction built on top of the loop itself. We have analyzed this system and found a number of interesting features not occurring in the conventional case with simply connected electrodes. In particular, the fluxoid quantization results in a frustration of the Josephson phase, which, in turn, reduces the junction critical current. Further, the possible stable states of the system are obtained by a self-consistent application of the principle of minimum energy. The theoretical findings are supported by measurements on a number of samples having different geometrical configuration. The experiments demonstrate that a very large signal-to-noise ratio can be achieved in the flux quanta detection.

Enhancing Resident Safety by Preventing Healthcare-Associated Infection: A National Initiative to Reduce Catheter-Associated Urinary Tract Infections in Nursing Homes

PubMed Central

Mody, Lona; Meddings, Jennifer; Edson, Barbara S.; McNamara, Sara E.; Trautner, Barbara W.; Stone, Nimalie D.; Krein, Sarah L.; Saint, Sanjay

2015-01-01

Preventing healthcare-associated infection (HAI) is a key contributor to enhancing resident safety in nursing homes. In 2013, the U.S. Department of Health and Human Services approved a plan to enhance resident safety by reducing HAIs in nursing homes, with particular emphasis on reducing indwelling catheter use and catheter-associated urinary tract infection (CAUTI). Lessons learned from a recent multimodal Targeted Infection Prevention program in a group of nursing homes as well as a national initiative to prevent CAUTI in over 950 acute care hospitals called “On the CUSP: STOP CAUTI” will now be implemented in nearly 500 nursing homes in all 50 states through a project funded by the Agency for Healthcare Research and Quality (AHRQ). This “AHRQ Safety Program in Long-Term Care: HAIs/CAUTI” will emphasize professional development in catheter utilization, catheter care and maintenance, and antimicrobial stewardship as well as promoting patient safety culture, team building, and leadership engagement. We anticipate that an approach integrating technical and socio-adaptive principles will serve as a model for future initiatives to reduce other infections, multidrug resistant organisms, and noninfectious adverse events among nursing home residents. PMID:25814630

Intermittent catheterisation for long-term bladder management (abridged cochrane review).

PubMed

Prieto, Jacqui A; Murphy, Catherine; Moore, Katherine N; Fader, Mandy J

2015-09-01

To review the evidence on strategies to reduce UTI, other complications or improve satisfaction in intermittent catheter (IC) users by comparing: (1) one catheter design, material or technique versus another; (2) sterile technique versus clean; or (3) single-use (sterile) or multiple-use (clean) catheters. We searched Cochrane Incontinence Group Specialised Trials Register, MEDLINE, EMBASE, CINAHL, ERIC, reference lists, and conference proceedings to November 2013. We contacted other investigators for unpublished data or clarification. Trial screening, assessment and data abstraction were all in accordance with the Cochrane handbook. Thirty one trials (13 RCTs and 18 randomized crossover trials), addressed the inclusion criteria comparing method or design and UTI/bacteriuria, other complications or participant assessed outcomes. Studies varied widely in follow-up, UTI definition and attrition; in some, data could not be combined. Where there were data, confidence intervals were wide and hence clinically important differences could neither be reliably identified nor ruled out. Current research evidence is weak and design issues are significant. It has not yet been established whether incidence of UTI, other complications such as haematuria, or user satisfaction are affected by sterile or clean technique, coated or uncoated catheters, single or multiple-use catheters or by any other strategy. For people using IC, choice of catheter will depend on personal preference, cost, portability, and ease of use. Individuals should discuss the catheter options with their healthcare practitioner. Cost-effectiveness analysis and use of the standard definition of UTI are essential in any proposed clinical trial. © 2015 Wiley Periodicals, Inc.

Estimating long-term multivariate progression from short-term data.

PubMed

Donohue, Michael C; Jacqmin-Gadda, Hélène; Le Goff, Mélanie; Thomas, Ronald G; Raman, Rema; Gamst, Anthony C; Beckett, Laurel A; Jack, Clifford R; Weiner, Michael W; Dartigues, Jean-François; Aisen, Paul S

2014-10-01

Diseases that progress slowly are often studied by observing cohorts at different stages of disease for short periods of time. The Alzheimer's Disease Neuroimaging Initiative (ADNI) follows elders with various degrees of cognitive impairment, from normal to impaired. The study includes a rich panel of novel cognitive tests, biomarkers, and brain images collected every 6 months for as long as 6 years. The relative timing of the observations with respect to disease pathology is unknown. We propose a general semiparametric model and iterative estimation procedure to estimate simultaneously the pathological timing and long-term growth curves. The resulting estimates of long-term progression are fine-tuned using cognitive trajectories derived from the long-term "Personnes Agées Quid" study. We demonstrate with simulations that the method can recover long-term disease trends from short-term observations. The method also estimates temporal ordering of individuals with respect to disease pathology, providing subject-specific prognostic estimates of the time until onset of symptoms. When the method is applied to ADNI data, the estimated growth curves are in general agreement with prevailing theories of the Alzheimer's disease cascade. Other data sets with common outcome measures can be combined using the proposed algorithm. Software to fit the model and reproduce results with the statistical software R is available as the grace package. ADNI data can be downloaded from the Laboratory of NeuroImaging. Copyright © 2014 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Central venous catheter-associated bloodstream infections in a pediatric intensive care unit: effect of the location of catheter insertion.

PubMed

Krishnaiah, Anil; Soothill, James; Wade, Angie; Mok, Quen Q; Ramnarayan, Padmanabhan

2012-05-01

To compare the rate of central venous catheter-associated bloodstream infections between pediatric intensive care unit admissions where central venous catheters were inserted within the same hospital (internal central venous catheters) and those where central venous catheters were inserted before transfer from other hospitals (external central venous catheters). Retrospective analysis of prospectively collected data. A tertiary care pediatric intensive care unit in London, UK. Consecutive pediatric intensive care unit admissions between May 2007 and March 2009. None. Catheter-associated bloodstream infections were identified using a widely accepted surveillance definition. The rate and time to occurrence of catheter-associated bloodstream infection were compared between internal and external nontunneled central venous catheters. A multilevel Cox-regression model was used to study the association between location of central venous catheter insertion and time to catheter-associated bloodstream infection. In total, 382 central venous catheters were studied (245 internal; 137 external) accounting for a total of 1,737 central venous catheter days. There was a higher catheter-associated bloodstream infection incidence density among external central venous catheters (23.1 [95% confidence interval 11.0-35.2] vs. 9.7 [95% confidence interval 3.9-15.5] per 1,000 catheter-days). Multivariable analyses demonstrated higher infection risk with external central venous catheters (hazard ratio 2.65 [95% confidence interval 1.18-5.96]) despite adjustment for confounding variables. The rate of catheter-associated bloodstream infections in the pediatric intensive care unit is significantly affected by external insertion of the central venous catheter. Future interventions to reduce nosocomial infections on pediatric intensive care units will need to be specifically targeted at this high-risk patient group.

Scientific Understanding from Long Term Observations: Insights from the Long Term Ecological Research (LTER) Program

NASA Astrophysics Data System (ADS)

Gosz, J.

2001-12-01

The network dedicated to Long Term Ecological Research (LTER) in the United States has grown to 24 sites since it was formed in 1980. Long-term research and monitoring are performed on parameters thatare basic to all ecosystems and are required to understand patterns, processes, and relationship to change. Collectively, the sites in the LTER Network provide opportunities to contrast marine, coastal, and continental regions, the full range of climatic gradients existing in North America, and aquatic and terrestrial habitats in a range of ecosystem types. The combination of common core areas and long-term research and monitoring in many habitats have allowed unprecedented abilities to understand and compare complex temporal and spatial dynamics associated with issues like climate change, effects of pollution, biodiversity and landuse. For example, McMurdo Dry Valley in the Antarctic has demonstrated an increase in glacier mass since 1993 which coincides with a period of cooler than normal summers and more than average snowfall. In contrast, the Bonanza Creek and Toolik Lake sites in Alaska have recorded a warming period unprecedented in the past 200 years. Nitrogen deposition effects have been identified through long-term watershed studies on biogeochemical cycles, especially at Coweeta Hydrological Lab, Harvard Forest, and the Hubbard Brook Experimental Forest. In aquatic systems, such as the Northern Temperate Lakes site, long-term data revealed time lags in effects of invaders and disturbance on lake communities. Biological recovery from an effect such as lake acidification was shown to lag behind chemical recovery. The long-term changes documented over 2 decades have been instrumental in influencing management practices in many of the LTER areas. In Puerto Rico, the Luquillo LTER demonstrated that dams obstruct migrations of fish and freshwater shrimp and water abstraction at low flows can completely obliterate downstream migration of juveniles and damage

Development of the safety control framework for shield tunneling in close proximity to the operational subway tunnels: case studies in mainland China.

PubMed

Li, Xinggao; Yuan, Dajun

2016-01-01

feasibility of using the remedial grouting to reduce the long-term settlement of the operational tunnels. The more and more segmental tunnels being constructed, there is an increasing need of the optical fiber measurement for tunnel movement monitoring in the near future.

Long-Term Opioid Therapy Reconsidered

PubMed Central

Von Korff, Michael; Kolodny, Andrew; Deyo, Richard A.; Chou, Roger

2012-01-01

In the past 20 years, primary care physicians have greatly increased prescribing of long-term opioid therapy. However, the rise in opioid prescribing has outpaced the evidence regarding this practice. Increased opioid availability has been accompanied by an epidemic of opioid abuse and overdose. The rate of opioid addiction among patients receiving long-term opioid therapy remains unclear, but research suggests that opioid misuse is not rare. Recent studies report increased risks for serious adverse events, including fractures, cardiovascular events, and bowel obstruction, although further research on medical risks is needed. New data indicate that opioid-related risks may increase with dose. From a societal perspective, higher-dose regimens account for the majority of opioids dispensed, so cautious dosing may reduce both diversion potential and patient risks for adverse effects. Limiting long-term opioid therapy to patients for whom it provides decisive benefits could also reduce risks. Given the warning signs and knowledge gaps, greater caution and selectivity are needed in prescribing long-term opioid therapy. Until stronger evidence becomes available, clinicians should err on the side of caution when considering this treatment. PMID:21893626

The role of laparoscopic surgery in the management of a malfunctioning peritoneal catheter.

PubMed

Alabi, A; Dholakia, S; Ablorsu, E

2014-11-01

Peritoneal catheter malfunction is a common complication of peritoneal dialysis (PD). It has a high failure rate with conservative management. Catheter replacement was historically the standard surgical treatment of choice. Nowadays, laparoscopy has been introduced as an alternative surgical modality to rescue the malfunctioning peritoneal catheter and also offers the possibility of replacement if indicated. The aim of this study was to compare the outcomes of these two surgical modalities. The medical records of consecutive patients who underwent surgical treatment for malfunctioning PD catheters (between January 2010 and April 2013) were analysed. The primary outcome included successful return to adequate PD. The secondary endpoint was length of catheter patency and the cause of catheter failure. A total of 32 cases were identified, of which 8 had open catheter replacement and 24 had a laparoscopic intervention. The overall median follow-up duration was 12.5 months. The success rate for laparoscopic surgery in terms of functioning catheter at 12 months was 62.5% but only 37.5% for open surgery. The mean length of catheter patency after laparoscopic intervention was 31.6 months compared with only 13.6 months for the open surgery group. The most common cause of catheter failure diagnosed during laparoscopic intervention was catheter migration (33.0%), followed by omental wrap and catheter blockage by fibrin/blood plug (25.0% each). Open surgery did not have any diagnostic potential. Laparoscopy is the treatment of choice for malfunctioning PD. Its proven benefit includes simultaneous identification of the aetiological cause of malfunction together with direct correction of this problem, thereby maximising outcome. It also allows for rapid recommencement of PD and avoidance of haemodialysis, saving cost and resources.

Time scales of tunneling decay of a localized state

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

Ban, Yue; Muga, J. G.; Sherman, E. Ya.

2010-12-15

Motivated by recent time-domain experiments on ultrafast atom ionization, we analyze the transients and time scales that characterize, aside from the relatively long lifetime, the decay of a localized state by tunneling. While the tunneling starts immediately, some time is required for the outgoing flux to develop. This short-term behavior depends strongly on the initial state. For the initial state, tightly localized so that the initial transients are dominated by over-the-barrier motion, the time scale for flux propagation through the barrier is close to the Buettiker-Landauer traversal time. Then a quasistationary, slow-decay process follows, which sets ideal conditions for observingmore » diffraction in time at longer times and distances. To define operationally a tunneling time at the barrier edge, we extrapolate backward the propagation of the wave packet that escaped from the potential. This extrapolated time is considerably longer than the time scale of the flux and density buildup at the barrier edge.« less

Very long-term sequelae of craniopharyngioma.

PubMed

Wijnen, Mark; van den Heuvel-Eibrink, Marry M; Janssen, Joseph A M J L; Catsman-Berrevoets, Coriene E; Michiels, Erna M C; van Veelen-Vincent, Marie-Lise C; Dallenga, Alof H G; van den Berge, J Herbert; van Rij, Carolien M; van der Lely, Aart-Jan; Neggers, Sebastian J C M M

2017-06-01

Studies investigating long-term health conditions in patients with craniopharyngioma are limited by short follow-up durations and generally do not compare long-term health effects according to initial craniopharyngioma treatment approach. In addition, studies comparing long-term health conditions between patients with childhood- and adult-onset craniopharyngioma report conflicting results. The objective of this study was to analyse a full spectrum of long-term health effects in patients with craniopharyngioma according to initial treatment approach and age group at craniopharyngioma presentation. Cross-sectional study based on retrospective data. We studied a single-centre cohort of 128 patients with craniopharyngioma treated from 1980 onwards (63 patients with childhood-onset disease). Median follow-up since craniopharyngioma presentation was 13 years (interquartile range: 5-23 years). Initial craniopharyngioma treatment approaches included gross total resection ( n  = 25), subtotal resection without radiotherapy ( n  = 44), subtotal resection with radiotherapy ( n  = 25), cyst aspiration without radiotherapy ( n  = 8), and 90 Yttrium brachytherapy ( n  = 21). Pituitary hormone deficiencies (98%), visual disturbances (75%) and obesity (56%) were the most common long-term health conditions observed. Different initial craniopharyngioma treatment approaches resulted in similar long-term health effects. Patients with childhood-onset craniopharyngioma experienced significantly more growth hormone deficiency, diabetes insipidus, panhypopituitarism, morbid obesity, epilepsy and psychiatric conditions compared with patients with adult-onset disease. Recurrence-/progression-free survival was significantly lower after initial craniopharyngioma treatment with cyst aspiration compared with other therapeutic approaches. Survival was similar between patients with childhood- and adult-onset craniopharyngioma. Long-term health conditions were comparable after

Long-term care in international perspective.

PubMed

Doty, P

1988-12-01

The findings of a study of long-term care policies in 18 countries are reported in this article. Initial data were collected by a questionnaire survey under the auspices of the International Social Security Association. These data were supplemented by published documents and government statistics obtained while researching long-term care for the International Social Security Association and, subsequently, for the Organization for Economic Cooperation and Development. The principal focus is a cross-national comparison of institutionalization rates for the elderly. Differences in use rates for medically oriented facilities are less than those for nonmedical residential long-term care facilities. Only a small amount of variation is related to demographic differences, such as older or more female elderly populations in those countries with higher institutionalization rates. Included also is a description of the modes of financing long-term care.

Compensation for PKMζ in long-term potentiation and spatial long-term memory in mutant mice

PubMed Central

Tsokas, Panayiotis; Hsieh, Changchi; Yao, Yudong; Lesburguères, Edith; Wallace, Emma Jane Claire; Tcherepanov, Andrew; Jothianandan, Desingarao; Hartley, Benjamin Rush; Pan, Ling; Rivard, Bruno; Farese, Robert V; Sajan, Mini P; Bergold, Peter John; Hernández, Alejandro Iván; Cottrell, James E; Shouval, Harel Z; Fenton, André Antonio; Sacktor, Todd Charlton

2016-01-01

PKMζ is a persistently active PKC isoform proposed to maintain late-LTP and long-term memory. But late-LTP and memory are maintained without PKMζ in PKMζ-null mice. Two hypotheses can account for these findings. First, PKMζ is unimportant for LTP or memory. Second, PKMζ is essential for late-LTP and long-term memory in wild-type mice, and PKMζ-null mice recruit compensatory mechanisms. We find that whereas PKMζ persistently increases in LTP maintenance in wild-type mice, PKCι/λ, a gene-product closely related to PKMζ, persistently increases in LTP maintenance in PKMζ-null mice. Using a pharmacogenetic approach, we find PKMζ-antisense in hippocampus blocks late-LTP and spatial long-term memory in wild-type mice, but not in PKMζ-null mice without the target mRNA. Conversely, a PKCι/λ-antagonist disrupts late-LTP and spatial memory in PKMζ-null mice but not in wild-type mice. Thus, whereas PKMζ is essential for wild-type LTP and long-term memory, persistent PKCι/λ activation compensates for PKMζ loss in PKMζ-null mice. DOI: http://dx.doi.org/10.7554/eLife.14846.001 PMID:27187150

Competitive short-term and long-term memory processes in spatial habituation.

PubMed

Sanderson, David J; Bannerman, David M

2011-04-01

Exposure to a spatial location leads to habituation of exploration such that, in a novelty preference test, rodents subsequently prefer exploring a novel location to the familiar location. According to Wagner's (1981) theory of memory, short-term and long-term habituation are caused by separate and sometimes opponent processes. In the present study, this dual-process account of memory was tested. Mice received a series of exposure training trials to a location before receiving a novelty preference test. The novelty preference was greater when tested after a short, rather than a long, interval. In contrast, the novelty preference was weaker when exposure training trials were separated by a short, rather than a long interval. Furthermore, it was found that long-term habituation was determined by the independent effects of the amount of exposure training and the number of exposure training trials when factors such as the intertrial interval and the cumulative intertrial interval were controlled. A final experiment demonstrated that a long-term reduction of exploration could be caused by a negative priming effect due to associations formed during exploration. These results provide evidence against a single-process account of habituation and suggest that spatial habituation is determined by both short-term, recency-based memory and long-term, incrementally strengthened memory.

Indwelling esophageal balloon catheter for benign esophageal stenosis in infants and children.

PubMed

van der Zee, David; Hulsker, Caroline

2014-04-01

Balloon dilatation of benign esophageal strictures is an established mode of therapy in adults and children. There remains a group of patients with refractory stenosis despite dilatation at regular intervals. An indwelling balloon catheter may offer an alternative. This is a retrospective study of 19 children who underwent esophagoscopy between 2004 and 2012 with placement of an indwelling balloon catheter for refractory esophageal stenosis. Total number of endoscopies, number of endoscopies with indwelling balloon catheter, as well as complications, reoperations, and mortality due to use of the balloon catheter were studied. Patient age ranged from 4 weeks to 15 years. The indwelling balloon catheter was used to treat refractory stenosis after corrective surgery of long gap esophageal atresia (n = 5), esophageal atresia with distal fistula (n = 2), refractory esophageal stenosis due to caustic esophageal burns (n = 7), reflux (n = 2), and stenosis of unknown cause (n = 3). With the indwelling balloon catheter in place, the mean number of endoscopies equalled four. Complications were restenosis after a symptom-free period for which a new indwelling balloon catheter was necessary (n = 3). Two others needed two to five additional dilations: balloon leakage requiring replacement (n = 7 in 5 patients), sputum retention (n = 1), and dislodgement (n = 5 in 4 patients). More importantly, there was no mortality or the need for any patient to undergo a surgical resection. The indwelling balloon catheter is safe to use and can be used by parents at home. More importantly it obviates the need for rethoracotomy/-scopy or esophageal replacement.

Business Students' Choice of Short-Term or Long-Term Study Abroad Opportunities

ERIC Educational Resources Information Center

Fitzsimmons, Stacey R.; Flanagan, David J.; Wang, Xiaodan

2013-01-01

Recent years have seen a proliferation of short-term study abroad opportunities. Although they are both supplementing and replacing semester-long study abroad programs, research has focused primarily on semester (long-term) programs. We draw on the theory of planned behavior (TPB) to explore factors that predict why students choose long-term and…

[Rotational stability of angiography catheters].

PubMed

Schröder, J; Weber, M

1992-10-01

Rotatory stability is a parameter that reflects the ability of a catheter to transmit a rotation applied at the outer end to the catheter tip for the purpose of selective probing. A method for measuring the rotatory stability is described, and the results of rotatory stability measurements of 70 different commercially available catheters are reported. There is an almost linear correlation between the rotatory stability and the difference between the respective fourth power of the external and internal diameter or, approximately, to the fourth power of the external diameter for catheters without wire reinforcement. With the same cross-sectional dimensions, the rotatory stability of teflon, polyethylene, and nylon catheters has an approximate ratio of 1:2:4. Wire reinforcement increases rotatory stability by an average factor of about 3. For catheters of calibers 5 F and 6 F, a correlation between the rotatory stability and the weight of the reinforcing wire mesh is apparent.

Brachial arteriovenous fistula as a complication of placement of a peripherally inserted central venous catheter: a case report and review of the literature.

PubMed

Tran, Hoang S; Burrows, Brian J; Zang, William A; Han, David C

2006-09-01

Peripherally inserted central venous catheter (PICC) lines have become a frequently used method of intravenous access for long-term administration of antibiotics, chemotherapy, and parenteral nutrition. Catheter-related complications involving the arterial tree are rare. We report a case of a 25-year-old woman with a history of difficult PICC line placement that presented with an arteriovenous fistula in the left arm. Duplex ultrasound confirmed the diagnosis of a brachial artery-to-brachial vein arteriovenous fistula (AVF), and the patient underwent surgical repair. To our knowledge, this is the first reported case of an AVF resulting from PICC line placement. Correction of AVF is indicated to alleviate symptoms as well as to prevent future complications.

Viridans Streptococci in Peritoneal Dialysis Peritonitis: Clinical Courses and Long-Term Outcomes

PubMed Central

Chao, Chia-Ter; Lee, Szu-Ying; Yang, Wei-Shun; Chen, Huei-Wen; Fang, Cheng-Chung; Yen, Chung-Jen; Chiang, Chih-Kang; Hung, Kuan-Yu; Huang, Jenq-Wen

2015-01-01

♦ Background: The clinical courses and long-term outcomes of viridans streptococcus (VS) peritoneal dialysis (PD) peritonitis remain unclear. ♦ Methods: We conducted a retrospective analysis of all PD patients in a single center with gram-positive cocci (GPC) peritonitis between 2005 and 2011, and divided them into 3 groups: VS, other streptococci and other GPC (apart from VS). Clinical characteristics and outcomes of the VS group were compared with the other streptococci and other GPC groups, with prognostic factors determined. ♦ Results: A total of 140 patients with 168 episodes of GPC peritonitis (44% of all peritonitis) were identified over 7 years. Among these, 18 patients (13%) developed VS peritonitis, while 14 patients (10%) developed other streptococcal peritonitis. Patients with VS peritonitis had a high cure rate by antibiotic alone (94%), despite a high polymicrobial yield frequency (28%). We found that VS peritonitis carried a lower risk of Tenckhoff catheter removal and relapsing episodes than other GPC peritonitis (6% vs 11%), and a lower mortality than other streptococci peritonitis (0% vs 7%). However, after the index peritonitis episodes, VS, other streptococci, and other GPC group had a significantly increased peritonitis incidence compared with the period before the index peritonitis (all p < 0.01). Patients with VS peritonitis had a significantly higher incidence of refractory peritonitis compared with other streptococci or other GPC peritonitis in the long term (both p < 0.01). ♦ Conclusions: VS poses a higher risk of subsequent refractory peritonitis after the index episode as compared with other streptococcal or GPC peritonitis. It might be prudent to monitor the technique of these patients with VS peritonitis closely to avoid further peritonitis episodes. PMID:24497584

Brain temperature measurement: A study of in vitro accuracy and stability of smart catheter temperature sensors.

PubMed

Li, Chunyan; Wu, Pei-Ming; Wu, Zhizhen; Ahn, Chong H; LeDoux, David; Shutter, Lori A; Hartings, Jed A; Narayan, Raj K

2012-02-01

The injured brain is vulnerable to increases in temperature after severe head injury. Therefore, accurate and reliable measurement of brain temperature is important to optimize patient outcome. In this work, we have fabricated, optimized and characterized temperature sensors for use with a micromachined smart catheter for multimodal intracranial monitoring. Developed temperature sensors have resistance of 100.79 ± 1.19Ω and sensitivity of 67.95 mV/°C in the operating range from15-50°C, and time constant of 180 ms. Under the optimized excitation current of 500 μA, adequate signal-to-noise ratio was achieved without causing self-heating, and changes in immersion depth did not introduce clinically significant errors of measurements (<0.01°C). We evaluated the accuracy and long-term drift (5 days) of twenty temperature sensors in comparison to two types of commercial temperature probes (USB Reference Thermometer, NIST-traceable bulk probe with 0.05°C accuracy; and IT-21, type T type clinical microprobe with guaranteed 0.1°C accuracy) under controlled laboratory conditions. These in vitro experimental data showed that the temperature measurement performance of our sensors was accurate and reliable over the course of 5 days. The smart catheter temperature sensors provided accuracy and long-term stability comparable to those of commercial tissue-implantable microprobes, and therefore provide a means for temperature measurement in a microfabricated, multimodal cerebral monitoring device.

Bladder Morphology Using 2 Different Catheter Designs

ClinicalTrials.gov

2017-04-10

Urologic Injuries; Urologic Diseases; Bladder Infection; Urinary Tract Infections; Mucosal Inflammation; Mucosal Infection; Bladder Injury; Catheter-Related Infections; Catheter Complications; Catheter; Infection (Indwelling Catheter); Pelvic Floor Disorders; Urinary Incontinence

Long Periodic Terms in the Solar System

NASA Technical Reports Server (NTRS)

Bretagnon, P.

1982-01-01

The long period variations of the first eight planets in the solar system are studied. First, the Lagrangian solution is calculated and then the long period terms with fourth order eccentricities and inclinations are introduced into the perturbation function. A second approximation was made taking into account the short period terms' contribution, namely the perturbations of first order with respect to the masses. Special attention was paid to the determination of the integration constants. The relative importance of the different contributions is shown. It is useless, for example, to introduce the long period terms of fifth order if no account has been taken of the short period terms. Meanwhile, the terms that have been neglected would not introduce large changes in the integration constants. Even so, the calculation should be repeated with higher order short period terms and fifth order long periods.

Long-Term Hearing Results After Ossiculoplasty.

PubMed

Cox, Matthew D; Trinidade, Aaron; Russell, James Shep; Dornhoffer, John L

2017-04-01

To determine if the OOPS index is predictive of long-term hearing results after ossiculoplasty. Case series with retrospective chart review. Tertiary care otology practice. Adult and pediatric patients (3-88 years of age). Ossiculoplasty with cartilage tympanoplasty, with or without mastoidectomy. Primary outcome measures included short-term hearing results (pure-tone average air-bone gap [PTA-ABG] measured between 60 days and 1 year after surgery), long-term hearing results (PTA-ABG measured ≥5 years after surgery), and the rate of successful ABG closure to ≤20 dB. Secondary measures included the need for revision surgery, delayed tympanic membrane graft failure, worsening conductive hearing loss (after an initially satisfactory hearing result), and recurrence of cholesteatoma. There was no significant difference between adults and children for short-term hearing results (average post-op PTA-ABG was 18.9 dB vs. 19.8 dB, respectively; p = 0.544), long-term hearing results (average final PTA-ABG was 19.3 dB vs. 19.4 dB, respectively; p = 0.922), or rate of ABG closure to less than 20 dB (63.1% vs. 58.0%, p = 0.282). Spearman's rank-order correlation (ρ) identified a strong positive correlation between OOPS index score and average post-operative PTA-ABG (ρ = 0.983; p < 0.001; 2-tailed), as well as average long-term PTA-ABG (ρ = 0.950, p < 0.001; 2-tailed). The OOPS index makes it possible to accurately prognosticate hearing outcomes in adult and pediatric patients undergoing ossiculoplasty in both the short term and the long term.

Short-term memory and long-term memory are still different.

PubMed

Norris, Dennis

2017-09-01

A commonly expressed view is that short-term memory (STM) is nothing more than activated long-term memory. If true, this would overturn a central tenet of cognitive psychology-the idea that there are functionally and neurobiologically distinct short- and long-term stores. Here I present an updated case for a separation between short- and long-term stores, focusing on the computational demands placed on any STM system. STM must support memory for previously unencountered information, the storage of multiple tokens of the same type, and variable binding. None of these can be achieved simply by activating long-term memory. For example, even a simple sequence of digits such as "1, 3, 1" where there are 2 tokens of the digit "1" cannot be stored in the correct order simply by activating the representations of the digits "1" and "3" in LTM. I also review recent neuroimaging data that has been presented as evidence that STM is activated LTM and show that these data are exactly what one would expect to see based on a conventional 2-store view. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Short-Term Memory and Long-Term Memory are Still Different

PubMed Central

2017-01-01

A commonly expressed view is that short-term memory (STM) is nothing more than activated long-term memory. If true, this would overturn a central tenet of cognitive psychology—the idea that there are functionally and neurobiologically distinct short- and long-term stores. Here I present an updated case for a separation between short- and long-term stores, focusing on the computational demands placed on any STM system. STM must support memory for previously unencountered information, the storage of multiple tokens of the same type, and variable binding. None of these can be achieved simply by activating long-term memory. For example, even a simple sequence of digits such as “1, 3, 1” where there are 2 tokens of the digit “1” cannot be stored in the correct order simply by activating the representations of the digits “1” and “3” in LTM. I also review recent neuroimaging data that has been presented as evidence that STM is activated LTM and show that these data are exactly what one would expect to see based on a conventional 2-store view. PMID:28530428

Fermi edge singularity in a tunnel junction

NASA Astrophysics Data System (ADS)

Zhang, Jin; Sherkunov, Yury; D'Ambrumenil, Nicholas; Muzykantskii, Boris

2010-03-01

We present results on the non-equilibrium Fermi edge singularity (FES) problem in tunnel junctions. The FES, which is present in a Fermi gas subject to any sudden change of potential, manifests itself in the final state many body interaction between the electrons in the leads [1]. We establish a connection between the FES problem in a tunnel junction and the Full Counting Statistics (FCS) for the device [2]. We find that the exact profile of the changing potential (or the profile for the barrier opening and closing in the tunnel junction case) strongly affects the overlap between the initial and final state of the Fermi gas. We factorize the contribution to the FES into two approximately independent terms: one is connected with the short time opening process while the other is concerned with the long time asymptotic effect, namely the Anderson orthogonality catastrophe. We consider applications to a localized level coupled through a tunnel barrier to a 1D lead driven out of equilibrium [3]. References: [1] G. Mahan, Phys. Rev. 163, 1612 (1967); P. Nozieres and C. T. De Dominicis, Phys. Rev. 178, 1079 (1969); P. Anderson, Phys. Rev. Lett. 18, 1049 (1967) [2] J. Zhang, Y. Sherkunov, N. d'Ambrumenil, and B. Muzykantskii, ArXiv:0909.3427 [3] D. Abanin and L. Levitov, Phys. Rev. Lett. 94, 186803 (2005)

The impact of organizational factors on the urinary incontinence care quality in long-term care hospitals: a longitudinal correlational study.

PubMed

Yoon, Ju Young; Lee, Ji Yun; Bowers, Barbara J; Zimmerman, David R

2012-12-01

With the rapid increase in the number of long-term care hospitals in Korea, care quality has become an important issue. Urinary incontinence is an important condition affecting many residents' quality of life. Thus, it is important that urinary incontinence be amenable to improving conditions with appropriate interventions, since a change in urinary incontinence status can reflect care quality in long-term care facilities if patient level factors are adjusted. We aim to examine the impact of organizational factors on urinary incontinence care quality defined as the improvement of urinary incontinence status or maintenance of continent status post-admission to Korean long-term care hospitals. DESIGN AND DATA: This is a longitudinal correlation study. Data came from two sources: monthly patient assessment reports using the Patient Assessment Instrument and the hospital information system from the Health Insurance Review and Assessment Services. The final analysis includes 5271 elderly adults without indwelling urinary catheter or urostomy who were admitted to 534 Korean long-term care hospitals in April 2008. Multi-level logistic analysis was used to explore the organizational factors that influence urinary incontinence care quality controlling for patient level factors. With respect to the organizational factors, the findings showed that location and RN/total nursing staff ratio variables were statistically significant, controlling for risk factors at the patient level. The odds of urinary incontinence improvement from admission in urban long-term care hospitals were 1.28 times higher than rural long-term care hospitals. In addition, when a long-term care hospital increased one standard deviation (0.19) in the RN ratio, the odds of urinary incontinence status improvement or maintenance of continence status from admission increased about 1.8 times. The most significant finding was that a higher RN to patient ratio and urban location were associated with better

Physics and Technology of Resonant-Tunneling Devices

DTIC Science & Technology

1992-07-01

Negative differential resistance, quantum-well inductance, suppressed shot noise, superlattice tunneling, Type-Il heterostructures, lattice...of these deviations is carried out in the accompanying manuscript of Appendix C. 3.1.3. Superlattice Resonant Tunneling In the 1970s, interest in...resonant-tunneling was driven by the desire to observe long-range coherent transport phenomena, such as Bloch oscillations in superlattice structures. In

Emergency coronary angioplasty with stenting using Cordis® diagnostic coronary catheters when there is difficulty in engaging guide catheters and bench evaluation of diagnostic and guide catheters.

PubMed

Arokiaraj, Mark Christopher

2018-02-01

Difficulty in engaging with guide catheters is not uncommon in acute emergencies. We aimed to evaluate the use of Cordis ® INFINITI diagnostic catheters to perform angioplasty in patients in whom the coronaries cannot be engaged using standard guide catheters. In 34 cases of acute coronary syndrome, when difficulty in engagement with two standard guide catheters was encountered with reasonable manipulations, angioplasty was performed using diagnostic catheters. In total, 40 stents were placed by this technique. Pushability and trackability, distal tip flexion and three-point bending tests were performed to evaluate the performance of the guide and diagnostic catheters. Angioplasty was performed easily in a setting where it would have been very difficult to perform. Coronary dissection occurred in one patient, treated by a stent. The stent and dilatation balloons were easily passed through the diagnostic catheters. Pressure tracings were clearly preserved with certain stent delivery systems, and at angioplasty, although there was slightly reduced opacification of the respective artery, the coronary anatomy was sufficiently visualized to perform angioplasty. No periprocedural target lesion complications were seen in any cases. Pushability and trackability tests showed good force transmission along a tortuous path with diagnostic catheters, and balanced force-displacement curves from three-point bending tests and distal tip softness tests. Angioplasty with stenting can be performed safely through 6F Cordis ® infiniti diagnostic catheters when difficulty in engaging guide catheters is encountered. Copyright © 2018 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

Long-Term Memory Performance in Adult ADHD.

PubMed

Skodzik, Timo; Holling, Heinz; Pedersen, Anya

2017-02-01

Memory problems are a frequently reported symptom in adult ADHD, and it is well-documented that adults with ADHD perform poorly on long-term memory tests. However, the cause of this effect is still controversial. The present meta-analysis examined underlying mechanisms that may lead to long-term memory impairments in adult ADHD. We performed separate meta-analyses of measures of memory acquisition and long-term memory using both verbal and visual memory tests. In addition, the influence of potential moderator variables was examined. Adults with ADHD performed significantly worse than controls on verbal but not on visual long-term memory and memory acquisition subtests. The long-term memory deficit was strongly statistically related to the memory acquisition deficit. In contrast, no retrieval problems were observable. Our results suggest that memory deficits in adult ADHD reflect a learning deficit induced at the stage of encoding. Implications for clinical and research settings are presented.

[The ISP (Safe Insertion of PICCs) protocol: a bundle of 8 recommendations to minimize the complications related to the peripherally inserted central venous catheters (PICC)].

PubMed

Emoli, Alessandro; Cappuccio, Serena; Marche, Bruno; Musarò, Andrea; Scoppettuolo, Giancarlo; Pittiruti, Mauro

2014-01-01

The ISP (Safe Insertion of PICCs) protocol: a bundle of 8 recommendations to minimize the complications related to the peripherally inserted central venous catheters (PICC). The insertion of a peripherally inserted central venous catheter (PICC) is not without risks. The Italian Group for the Study of Long-Term Central Venous Access Devices (GAVeCeLT) has developed a protocol (SIP: Safe Implantation of PICCs) with the aim of minimizing the risks which may be associated with the placement of PICCs. The protocol is based on recommendations available in the literature and on the main clinical practice guidelines. The SIP protocol, a bundle of evidence-based recommendations, it is is easy to use, inexpensive, and cost-effective. If routinely used and carefully inplemented, it greatly reduces complications such as failure of venipuncture, accidental arterial puncture, damage of median nerve, infection and catheter related venous thrombosis.

Detecting the presence of an indwelling urinary catheter and urinary symptoms in hospitalized patients using natural language processing.

PubMed

Gundlapalli, Adi V; Divita, Guy; Redd, Andrew; Carter, Marjorie E; Ko, Danette; Rubin, Michael; Samore, Matthew; Strymish, Judith; Krein, Sarah; Gupta, Kalpana; Sales, Anne; Trautner, Barbara W

2017-07-01

To develop a natural language processing pipeline to extract positively asserted concepts related to the presence of an indwelling urinary catheter in hospitalized patients from the free text of the electronic medical note. The goal is to assist infection preventionists and other healthcare professionals in determining whether a patient has an indwelling urinary catheter when a catheter-associated urinary tract infection is suspected. Currently, data on indwelling urinary catheters is not consistently captured in the electronic medical record in structured format and thus cannot be reliably extracted for clinical and research purposes. We developed a lexicon of terms related to indwelling urinary catheters and urinary symptoms based on domain knowledge, prior experience in the field, and review of medical notes. A reference standard of 1595 randomly selected documents from inpatient admissions was annotated by human reviewers to identify all positively and negatively asserted concepts related to indwelling urinary catheters. We trained a natural language processing pipeline based on the V3NLP framework using 1050 documents and tested on 545 documents to determine agreement with the human reference standard. Metrics reported are positive predictive value and recall. The lexicon contained 590 terms related to the presence of an indwelling urinary catheter in various categories including insertion, care, change, and removal of urinary catheters and 67 terms for urinary symptoms. Nursing notes were the most frequent inpatient note titles in the reference standard document corpus; these also yielded the highest number of positively asserted concepts with respect to urinary catheters. Comparing the performance of the natural language processing pipeline against the human reference standard, the overall recall was 75% and positive predictive value was 99% on the training set; on the testing set, the recall was 72% and positive predictive value was 98%. The performance on

Virtual Models of Long-Term Care

ERIC Educational Resources Information Center

Phenice, Lillian A.; Griffore, Robert J.

2012-01-01

Nursing homes, assisted living facilities and home-care organizations, use web sites to describe their services to potential consumers. This virtual ethnographic study developed models representing how potential consumers may understand this information using data from web sites of 69 long-term-care providers. The content of long-term-care web…

Catheter ablation of atrial fibrillation using remote magnetic catheter navigation: a case-control study.

PubMed

Arya, Arash; Zaker-Shahrak, Ruzbeh; Sommer, Phillip; Bollmann, Andreas; Wetzel, Ulrike; Gaspar, Thomas; Richter, Sergio; Husser, Daniela; Piorkowski, Christopher; Hindricks, Gerhard

2011-01-01

To compare the acute and the 6 month outcome of catheter ablation of atrial fibrillation (AF) using irrigated tip magnetic catheter and remote magnetic cathter navigation (RMN) with manual catheter navigation (MCN) in patients with paroxysmal and persistent AF. In this retrospective analysis 356 patients (235 male, mean age: 57.9 ± 10.9 years) with AF (70.5%, paroxysmal) who underwent catheter ablation between August 2007 and May 2008 using either RMN (n = 70, 46 male, mean age: 57.9 ± 10.1 years, 50% paroxysmal) or MCN (n = 286, 189 male, mean age: 58.0 ± 13.9 years, 75.5% paroxysmal) were included. All patients completed an intensive follow-up strategy. Complete pulmonary vein isolation was achieved in 87.6 and 99.6% of patients in RMN and MCN groups, respectively (P < 0.05). The procedure, fluoroscopy, and radiofrequency application times were 223 ± 44 vs. 166 ± 52 min (P < 0.0001), 13.7 ± 7.8 vs. 34.5 ± 15.1 min (P < 0.0001), and 75.4 ± 20.9 vs. 53.2 ± 21.4 min (P < 0.0001) in RMN and MCN groups, respectively. Seven (10.0%) and 28 (9.8%) patients in RMN and MCN groups received antiarrhythmic medications during the follow-up (P = 0.96). All the patients completed the 6 month follow-up. Freedom from AF at 6 months was achieved in 57.8 and 66.4% of the patients in RMN and MCN groups, respectively (P = 0.196). In patients without previous AF catheter ablation procedure the freedom from AF at 6 months were 68.2 and 60.5% in the MCN and RMN groups, respectively (P = 0.36). Catheter ablation using irrigated tip magnetic catheter and RMN is an effective and safe method for catheter ablation of AF. Compared to manual catheter navigation, the procedure and radiofrequency application times were longer and fluoroscopy time was shorter in the RMN group compared with the MCN group.

Extended wearing trial of Trifield lens device for 'tunnel vision'.

PubMed

Woods, Russell L; Giorgi, Robert G; Berson, Eliot L; Peli, Eli

2010-05-01

Severe visual field constriction (tunnel vision) impairs the ability to navigate and walk safely. We evaluated Trifield glasses as a mobility rehabilitation device for tunnel vision in an extended wearing trial. Twelve patients with tunnel vision (5-22 degrees wide) due to retinitis pigmentosa or choroideremia participated in the 5-visit wearing trial. To expand the horizontal visual field, one spectacle lens was fitted with two apex-to-apex prisms that vertically bisected the pupil on primary gaze. This provides visual field expansion at the expense of visual confusion (two objects with the same visual direction). Patients were asked to wear these spectacles as much as possible for the duration of the wearing trial (median 8, range 6-60 weeks). Clinical success (continued wear, indicating perceived overall benefit), visual field expansion, perceived direction and perceived visual ability were measured. Of 12 patients, nine chose to continue wearing the Trifield glasses at the end of the wearing trial. Of those nine patients, at long-term follow-up (35-78 weeks), three reported still wearing the Trifield glasses. Visual field expansion (median 18, range 9-38 degrees) was demonstrated for all patients. No patient demonstrated adaptation to the change in visual direction produced by the Trifield glasses (prisms). For reported difficulty with obstacles, some differences between successful and non-successful wearers were found. Trifield glasses provided reported benefits in obstacle avoidance to 7 of the 12 patients completing the wearing trial. Crowded environments were particularly difficult for most wearers. Possible reasons for long-term discontinuation and lack of adaptation to perceived direction are discussed.

Prevalence of Long-Term Opioid Use in Long-Stay Nursing Home Residents.

PubMed

Hunnicutt, Jacob N; Chrysanthopoulou, Stavroula A; Ulbricht, Christine M; Hume, Anne L; Tjia, Jennifer; Lapane, Kate L

2018-01-01

Overall and long-term opioid use among older adults have increased since 1999. Less is known about opioid use in older adults in nursing homes (NHs). Cross-sectional. U.S. NHs (N = 13,522). Long-stay NH resident Medicare beneficiaries with a Minimum Data Set 3.0 (MDS) assessment between April 1, 2012, and June 30, 2012, and 120 days of follow-up (N = 315,949). We used Medicare Part D claims to measure length of opioid use in the 120 days from the index assessment (short-term: ≤30 days, medium-term: >30-89 days, long-term: ≥90 days), adjuvants (e.g., anticonvulsants), and other pain medications (e.g., corticosteroids). MDS assessments in the follow-up period were used to measure nonpharmacological pain management use. Modified Poisson models were used to estimate adjusted prevalence ratios (aPR) and 95% confidence intervals (CI) for age, gender, race and ethnicity, cognitive and physical impairment, and long-term opioid use. Of all long-stay residents, 32.4% were prescribed any opioid, and 15.5% were prescribed opioids long-term. Opioid users (versus nonusers) were more commonly prescribed pain adjuvants (32.9% vs 14.9%), other pain medications (25.5% vs 11.0%), and nonpharmacological pain management (24.5% vs 9.3%). Long-term opioid use was higher in women (aPR = 1.21, 95% CI = 1.18-1.23) and lower in racial and ethnic minorities (non-Hispanic blacks vs whites: APR = 0.93, 95% CI = 0.90-0.94) and those with severe cognitive impairment (vs no or mild impairment, aPR = 0.82, 95% CI = 0.79-0.83). One in seven NH residents was prescribed opioids long-term. Recent guidelines on opioid prescribing for pain recommend reducing long-term opioid use, but this is challenging in NHs because residents may not benefit from nonpharmacological and nonopioid interventions. Studies to address concerns about opioid safety and effectiveness (e.g., on pain and functional status) in NHs are needed. © 2017, Copyright the Authors Journal compilation © 2017, The American Geriatrics

Is it feasible to diagnose catheter-related candidemia without catheter withdrawal?

PubMed

Fernández-Cruz, Ana; Martín-Rabadán, Pablo; Suárez-Salas, Marisol; Rojas-Wettig, Loreto; Pérez, María Jesús; Guinea, Jesús; Guembe, María; Peláez, Teresa; Sánchez-Carrillo, Carlos; Bouza, Emilio

2014-07-01

Many bloodstream infections (BSI) in patients with central venous catheters (CVC) are not catheter-related (CR). Assessment of catheter involvement without catheter withdrawal has not been studied in candidemia. We assessed the value of conservative techniques to evaluate catheters as the origin of candidemia in patients with CVC in a prospective cohort study (superficial Gram stain and culture, Kite technique (Gram stain and culture of the first 1 cm blood drawn from the CVC), proportion of positive blood cultures (PPBCs), differential time to positivity (DTP), and minimal time to positivity (MTP)). All catheters were cultured at withdrawal. From June 2008 to January 2012, 22 cases fulfilled the inclusion criteria. CR-candidemia (CRC) was confirmed in 10. Validity values for predicting CRC were: superficial Gram stain (S, 30%; Sp, 81.83%; PPV, 60%; NPV, 56.3%; Ac, 57.1%), superficial cultures (S, 40%; Sp, 75%; PPV, 57.1%; NPV, 60%; Ac, 59.1%), Kite Gram stain (S, 33.3%; Sp, 66.7%; PPV, 50%; NPV, 50%; Ac, 50%), Kite culture (S, 80%; Sp, 66.7%; PPV, 66.7%; NPV, 80%; Ac, 72.7%), PPBC (S, 50%; Sp, 41.7%; PPV, 41.7%; NPV, 50.0%; Ac, 45.5%), DTP (S, 100%; Sp, 33.3%; PPV, 55.6%; NPV, 100%; Ac, 63.6%), and MTTP (S, 70%; Sp, 58.3%; PPV, 58.3%; NPV, 70%; Ac, 63.6%). While combinations of two tests improved sensitivity and NPV, more than two tests did not improve validity values. Classic tests to assess CR-BSI caused by bacteria cannot be reliably used to diagnose CRC. Combinations of tests could be useful, but more and larger studies are required. © The Author 2014. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Long-term prediction test procedure for most ICs, based on linear response theory

NASA Technical Reports Server (NTRS)

Litovchenko, V.; Ivakhnenko, I.

1991-01-01

Experimentally, thermal annealing is known to be a factor which enables a number of different integrated circuits (IC's) to recover their operating characteristics after suffering radiation damage in the space radiation environment; thus, decreasing and limiting long term cumulative total-dose effects. This annealing is also known to be accelerated at elevated temperatures both during and after irradiation. Linear response theory (LRT) was applied, and a linear response function (LRF) to predict the radiation/annealing response of sensitive parameters of IC's for long term (several months or years) exposure to the space radiation environment were constructed. Compressing the annealing process from several years in orbit to just a few hours or days in the laboratory is achieved by subjecting the IC to elevated temperatures or by increasing the typical spaceflight dose rate by several orders of magnitude for simultaneous radiation/annealing only. The accomplishments are as follows: (1) the test procedure to make predictions of the radiation response was developed; (2) the calculation of the shift in the threshold potential due to the charge distribution in the oxide was written; (3) electron tunneling processes from the bulk Si to the oxide region in an MOS IC were estimated; (4) in order to connect the experimental annealing data to the theoretical model, constants of the model of the basic annealing process were established; (5) experimental data obtained at elevated temperatures were analyzed; (6) time compression and reliability of predictions for the long term region were shown; (7) a method to compress test time and to make predictions of response for the nonlinear region was proposed; and (8) nonlinearity of the LRF with respect to log(t) was calculated theoretically from a model.

Adaptation of the CVT algorithm for catheter optimization in high dose rate brachytherapy

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

Poulin, Eric; Fekete, Charles-Antoine Collins; Beaulieu, Luc

2013-11-15

Purpose: An innovative, simple, and fast method to optimize the number and position of catheters is presented for prostate and breast high dose rate (HDR) brachytherapy, both for arbitrary templates or template-free implants (such as robotic templates).Methods: Eight clinical cases were chosen randomly from a bank of patients, previously treated in our clinic to test our method. The 2D Centroidal Voronoi Tessellations (CVT) algorithm was adapted to distribute catheters uniformly in space, within the maximum external contour of the planning target volume. The catheters optimization procedure includes the inverse planning simulated annealing algorithm (IPSA). Complete treatment plans can then bemore » generated from the algorithm for different number of catheters. The best plan is chosen from different dosimetry criteria and will automatically provide the number of catheters and their positions. After the CVT algorithm parameters were optimized for speed and dosimetric results, it was validated against prostate clinical cases, using clinically relevant dose parameters. The robustness to implantation error was also evaluated. Finally, the efficiency of the method was tested in breast interstitial HDR brachytherapy cases.Results: The effect of the number and locations of the catheters on prostate cancer patients was studied. Treatment plans with a better or equivalent dose distributions could be obtained with fewer catheters. A better or equal prostate V100 was obtained down to 12 catheters. Plans with nine or less catheters would not be clinically acceptable in terms of prostate V100 and D90. Implantation errors up to 3 mm were acceptable since no statistical difference was found when compared to 0 mm error (p > 0.05). No significant difference in dosimetric indices was observed for the different combination of parameters within the CVT algorithm. A linear relation was found between the number of random points and the optimization time of the CVT algorithm. Because

A Retrospective Comparison of Ultrasound-Assisted Catheter-Directed Thrombolysis and Catheter-Directed Thrombolysis Alone for Treatment of Proximal Deep Vein Thrombosis

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

Tichelaar, Vladimir Y. I. G., E-mail: ynse.i.tichelaar@uit.no; Brodin, Ellen E.; Vik, Anders

BackgroundRecent studies have suggested that catheter-directed thrombolysis (CDT) reduces development of post-thrombotic syndrome (PTS). Ultrasound-assisted CDT (USCDT) might enhance the efficiency of thrombolysis. We aimed to compare USCDT with CDT on efficacy, safety, development of PTS, and quality of life after long-term follow-up.MethodsWe describe a retrospective case series of 94 consecutive patients admitted with iliofemoral or more proximal deep vein thrombosis (DVT) to the University Hospital from 2002 to 2011, treated either with CDT or USCDT. Scheduled follow-up visits took place between April 2013 and January 2014. Venography measured the degree of residual luminal obstruction of the affected veins. Eachmore » patient completed the Short Form 36-item health survey assessment and the Venous Insufficiency Epidemiological and Economic Study-Quality of Life/Symptoms questionnaires. PTS was assessed using the Villalta scale.ResultsRisk factors of DVT were equally distributed between groups. In the USCDT group, we observed a significant decline in the duration of thrombolytic treatment (<48 h: 27 vs. 10 %), shortened hospital stay (median 6.0 days (IQR 5.0–9.0) vs. 8.0 (IQR 5.8–12.0)), and less implantation of (intravenous) stents (30 vs. 55 %). There was no difference in patency (76 vs. 79 % fully patent), prevalence of PTS (52 vs. 55 %), or quality of life between groups after long-term follow-up (median 65 months, range: 15–141).ConclusionsIn this observational study, USCDT was associated with shortened treatment duration, shorter hospital stay, and less intravenous stenting, compared to CDT alone without affecting the long-term prevalence of PTS or quality of life.« less

Complex network structure influences processing in long-term and short-term memory.

PubMed

Vitevitch, Michael S; Chan, Kit Ying; Roodenrys, Steven

2012-07-01

Complex networks describe how entities in systems interact; the structure of such networks is argued to influence processing. One measure of network structure, clustering coefficient, C, measures the extent to which neighbors of a node are also neighbors of each other. Previous psycholinguistic experiments found that the C of phonological word-forms influenced retrieval from the mental lexicon (that portion of long-term memory dedicated to language) during the on-line recognition and production of spoken words. In the present study we examined how network structure influences other retrieval processes in long- and short-term memory. In a false-memory task-examining long-term memory-participants falsely recognized more words with low- than high-C. In a recognition memory task-examining veridical memories in long-term memory-participants correctly recognized more words with low- than high-C. However, participants in a serial recall task-examining redintegration in short-term memory-recalled lists comprised of high-C words more accurately than lists comprised of low-C words. These results demonstrate that network structure influences cognitive processes associated with several forms of memory including lexical, long-term, and short-term.

Evaluation of urinary catheters coated with sustained-release varnish of chlorhexidine in mitigating biofilm formation on urinary catheters in dogs.

PubMed

Segev, G; Bankirer, T; Steinberg, D; Duvdevani, M; Shapur, N K; Friedman, M; Lavy, E

2013-01-01

Biofilm formation occurs commonly on urinary catheters. To assess the efficacy of urinary catheters coated with sustained-release varnish of chlorhexidine in decreasing catheter-associated biofilm formation in dogs. Thirty client-owned dogs. Prospective study. Thirteen dogs were catheterized with urinary catheters coated with sustained-release varnish of chlorhexidine (study group), and 13 dogs were catheterized with an untreated urinary catheter (control group). Presence and intensity of biofilm formation on the urinary catheters were assessed and compared between the groups by evaluating colony-forming units (CFU) of biofilm bacteria, and semiquantitatively, using confocal laser scanning microscopy and electron microscopy. None of the dogs experienced adverse effects associated with the presence of the urinary catheters. Median CFU count of biofilm bacteria at all portions of the urinary catheter was significantly (P < .001) lower in the study compared with the control group. The degree of biofilm formation on the urinary catheters, as evaluated by confocal laser scanning microscopy and electron microscopy, was significantly lower in the study compared with the control group. Electron microscopy examination identified crystals on some of the urinary catheters. The proportion of catheters on which crystals were observed was significantly lower on the distal part of the urinary catheter in the study group compared with the control group (16.7% versus 66.7%, respectively; P = .04). Chlorhexidine sustained-release varnish-coated urinary catheters effectively decrease urinary catheter-associated biofilm formation in dogs. Copyright © 2012 by the American College of Veterinary Internal Medicine.

Randomized controlled trial of local progesterone vs corticosteroid injection for carpal tunnel syndrome.

PubMed

Raeissadat, S A; Shahraeeni, S; Sedighipour, L; Vahdatpour, B

2017-10-01

A number of studies have demonstrated the neuroprotective effects of progesterone and its influence on the recovery after neural injury. Few studies investigated the efficacy of local progesterone in carpal tunnel syndrome. The objective of this study was to compare the long-term effects of progesterone vs corticosteroid local injections in patients with mild and moderate carpal tunnel syndrome. In this randomized clinical trial, 78 patients with carpal tunnel syndrome were assigned to two groups. Patients were treated with a single local injection of triamcinolone acetonide in one group and single local injection of hydroxy progesterone in the other group. Variables including pain (based on visual analogue scale), symptom severity, and functional status (based on Bostone/Levine symptom severity and functional status scale) and nerve conduction study were evaluated before and 6 months after the treatments. All outcome measures including pain and electrophysiologic findings, improved in both groups and there were no meaningful differences between two groups regarding mentioned variables except for functional outcome, which was significantly better in progesterone compared with corticosteroid group at 6-month follow-up (P=.04). The efficacy of progesterone local injection in mild and moderate CTS is equal and somehow superior to corticosteroid injection for relieving symptoms and improving functional and electrophysiologic findings at long-term follow-up. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Toxicity testing of urinary catheters.

PubMed

Talja, M; Andersson, L C; Ruutu, M; Alfthan, O

1985-10-01

The tissue toxicity of 23 urinary catheter batches (6 latex and 2 non-latex brands) was tested in vitro and in vivo. In vitro, a human T-cell leukemia line (JM) was cultured in the presence of different concentrations of eluates made from the catheters. The cytotoxicity of the eluates was assessed from their ability to inhibit DNA synthesis measured by incorporation of 3H-thymidine. In vivo, two methods were used. Strips of catheters were implanted into the rabbit dorsal muscle and pieces of catheters were implanted into the rat peritoneal cavity. After four days, the foreign body reaction, type of inflammation and necrosis were quantified macroscopically and by light microscopy. The results of the in vitro cytotoxicity test were correlated with those of in vivo methods. The rat peritoneal implantation test correlated better with the cell culture test (P less than 0.01) than with the rabbit muscle implantation test (P less than 0.05). Based on the clinical experience of urethral stricture complications caused by urinary catheters, catheters yielding eluate which at 30% dilution inhibited 50% DNA synthesis were regarded as toxic. According to this, the rabbit muscle implantation test was not reliable in testing the tissue toxicity of urinary catheters, while the cell culture test was quantitative and seemed to correlate with both the rat peritoneal implantation test and with the clinical complications observed.

The role of interventional radiology in management of benign and malignant gynecologic diseases.

PubMed

Yu, Hyeon; Stavas, Joseph M

2013-10-01

This article focuses on the role of interventional radiology in the therapeutic and diagnostic management of benign and malignant gynecologic conditions. The subspecialty of interventional radiology utilizes minimally invasive advanced image-guided percutaneous techniques in gynecology that include central venous catheter placement, fluid aspiration, drainage catheter placement, tissue biopsy, inferior vena cava filter placement, and pelvic arterial embolization. Central venous catheters, such as ports, peripherally inserted central catheters, and tunneled catheters, are placed for intermediate to long-term intravenous chemotherapy or total parental nutrition or antibiotics. Patients with refractory malignant ascites or pleural effusion from seeding of advanced gynecologic cancers may benefit by percutaneous aspiration of fluid collections or placement of drainage catheters. Postoperative fluid collections including abscess, seroma, or lymphocele are managed by percutaneous drainage catheter insertion. Pelvic, peritoneal, or retroperitoneal masses can be sampled by image-guided percutaneous biopsy or aspiration of fluid to determine a pathologic diagnosis. Certain patients are at risk for deep venous thrombosis with pulmonary embolism and may benefit from an inferior vena cava filter. Patients with uncontrolled postoperative or postpartum bleeding can be effectively managed with emergent transarterial pelvic embolization. Each of the aforementioned interventions with indications, expected benefits, and complications is described including a published literature.

Long-term outcomes of acute kidney injury.

PubMed

Coca, Steven G

2010-05-01

The goal of this review is to summarize the recent plethora of data that relate to long-term outcomes after acute kidney injury (AKI). Surviving patients with AKI are still at high risk for long-term adverse outcomes, even if serum creatinine returns to normal. After adjusting for potential confounders, many recent studies have demonstrated that AKI is independently associated with chronic kidney disease, end-stage renal disease, and premature death. Unfortunately, definitive evidence from randomized controlled trials demonstrating that prevention or treatment of AKI prevents long-term adverse outcomes is not yet available. AKI is clearly a prognostic marker for poor long-term outcomes, but more studies will be needed to determine whether AKI is truly causal and whether or not the risk is modifiable.

Long-term outcome of primary endoscopic realignment for bulbous urethral injuries: risk factors of urethral stricture.

PubMed

Seo, Ill Young; Lee, Jea Whan; Park, Seung Chol; Rim, Joung Sik

2012-12-01

Although endoscopic realignment has been accepted as a standard treatment for urethral injuries, the long-term follow-up data on this procedure are not sufficient. We report the long-term outcome of primary endoscopic realignment in bulbous urethral injuries. Patients with bulbous urethral injuries were treated by primary endoscopic realignment between 1991 and 2005. The operative procedure included suprapubic cystostomy and transurethral catheterization using a guide wire, within 72 hours of injury. The study population included 51 patients with a minimum follow-up duration of 5 years. The most common causes of the injuries were straddle injury from falling down (74.5%), and pelvic bone fracture (7.8%). Gross hematuria was the most common complaint (92.2%). Twenty-three patients (45.1%) had complete urethral injuries. The mean time to operation after the injury was 38.8±43.2 hours. The mean operation time and mean indwelling time of a urethral Foley catheter were 55.5±37.6 minutes and 22.0±11.9 days, respectively. Twenty out of 51 patients (39.2%) were diagnosed with urethral stricture in 89.1±36.6 months after surgery. A multivariate analysis revealed that young age and operation time were independent risk factors for strictures as a complication of urethral realignment (hazard ratio [HR], 6.554, P=0.032; HR, 6.206, P=0.035). Urethral stricture commonly developed as a postoperative complication of primary endoscopic urethral realignment for bulbous urethral injury, especially in young age and long operation time.

Long-term outcome of bare-fiber hybrid laser prostatectomy with transurethral scraping.

PubMed

Jain, Arun; Shah, Tariq K

2008-08-01

To present long-term follow-up results of 116 patients treated with laser ablation of the prostate and transurethral scraping (LAP/TUS) that involves vaporization and coagulation with potassium titanyl phosphate (KTP):YAG (yttrium-aluminum-garnet) (40 W) and neodymium (Nd):YAG (60 W) lasers, respectively, followed by scraping of the debris with a resectoscope. A total of 116 consecutive men (mean age 70 +/- 9 yrs) who underwent LAP/TUS for urinary retention or severe lower urinary tract symptoms were assessed by uroflowmetry, International Prostate Symptom Score (IPSS) and quality of life (QoL) score. The results of the prospectively recorded preoperative values were compared with values recorded at 3-months and annually thereafter for up to 8 postoperative years. Mean prostate size was 38.2(+/- 16.8) mL. After a mean/median follow-up of 84 months (range 60-103 months), 62 (80%) of 78 living patients completed the last follow-up assessment. Overall, 6 (5.2%) patients needed a long-term indwelling catheter and 7(6%) underwent reoperation. Preoperative v postoperative values at the last follow-up for the measured parameters were: IPSS 21.2 (+/- 6.9) v 10.2 (+/- 7.3); QoL score 4.3 (+/-1.1) v 1.9 (+/- 1.4); postvoid residual: 152 (+/- 138) v 62.2 (+/- 97.1) mL; peak flow rate 9.3 (+/- 3.9) versus 15.4(+/- 9.9) mL/s and average flow rate 4.4 (+/- 2.1) v 7.7 (+/- 6.3) mL/s respectively. There was no significant change in any of these parameters after the 7-year median follow-up compared with the improvements observed at 3 months postoperatively. LAP/TUS produces long-lasting relief in bladder outlet obstruction symptoms caused by prostatic enlargement with 50% to 129% improvement in mean IPSS scores and uroflowmetry parameters maintained even after a mean follow-up of 7 years.

Long-term metapopulation study of the Glanville fritillary butterfly (Melitaea cinxia): survey methods, data management, and long-term population trends.

PubMed

Ojanen, Sami P; Nieminen, Marko; Meyke, Evgeniy; Pöyry, Juha; Hanski, Ilkka

2013-10-01

Long-term observational studies conducted at large (regional) spatial scales contribute to better understanding of landscape effects on population and evolutionary dynamics, including the conditions that affect long-term viability of species, but large-scale studies are expensive and logistically challenging to keep running for a long time. Here, we describe the long-term metapopulation study of the Glanville fritillary butterfly (Melitaea cinxia) that has been conducted since 1991 in a large network of 4000 habitat patches (dry meadows) within a study area of 50 by 70 km in the Åland Islands in Finland. We explain how the landscape structure has been described, including definition, delimitation, and mapping of the habitat patches; methods of field survey, including the logistics, cost, and reliability of the survey; and data management using the EarthCape biodiversity platform. We describe the long-term metapopulation dynamics of the Glanville fritillary based on the survey. There has been no long-term change in the overall size of the metapopulation, but the level of spatial synchrony and hence the amplitude of fluctuations in year-to-year metapopulation dynamics have increased over the years, possibly due to increasing frequency of exceptional weather conditions. We discuss the added value of large-scale and long-term population studies, but also emphasize the need to integrate more targeted experimental studies in the context of long-term observational studies. For instance, in the case of the Glanville fritillary project, the long-term study has produced an opportunity to sample individuals for experiments from local populations with a known demographic history. These studies have demonstrated striking differences in dispersal rate and other life-history traits of individuals from newly established local populations (the offspring of colonizers) versus individuals from old, established local populations. The long-term observational study has stimulated the

Long-term metapopulation study of the Glanville fritillary butterfly (Melitaea cinxia): survey methods, data management, and long-term population trends

PubMed Central

Ojanen, Sami P; Nieminen, Marko; Meyke, Evgeniy; Pöyry, Juha; Hanski, Ilkka

2013-01-01

Long-term observational studies conducted at large (regional) spatial scales contribute to better understanding of landscape effects on population and evolutionary dynamics, including the conditions that affect long-term viability of species, but large-scale studies are expensive and logistically challenging to keep running for a long time. Here, we describe the long-term metapopulation study of the Glanville fritillary butterfly (Melitaea cinxia) that has been conducted since 1991 in a large network of 4000 habitat patches (dry meadows) within a study area of 50 by 70 km in the Åland Islands in Finland. We explain how the landscape structure has been described, including definition, delimitation, and mapping of the habitat patches; methods of field survey, including the logistics, cost, and reliability of the survey; and data management using the EarthCape biodiversity platform. We describe the long-term metapopulation dynamics of the Glanville fritillary based on the survey. There has been no long-term change in the overall size of the metapopulation, but the level of spatial synchrony and hence the amplitude of fluctuations in year-to-year metapopulation dynamics have increased over the years, possibly due to increasing frequency of exceptional weather conditions. We discuss the added value of large-scale and long-term population studies, but also emphasize the need to integrate more targeted experimental studies in the context of long-term observational studies. For instance, in the case of the Glanville fritillary project, the long-term study has produced an opportunity to sample individuals for experiments from local populations with a known demographic history. These studies have demonstrated striking differences in dispersal rate and other life-history traits of individuals from newly established local populations (the offspring of colonizers) versus individuals from old, established local populations. The long-term observational study has stimulated the

Long-Term Dynamics of Autonomous Fractional Differential Equations

NASA Astrophysics Data System (ADS)

Liu, Tao; Xu, Wei; Xu, Yong; Han, Qun

This paper aims to investigate long-term dynamic behaviors of autonomous fractional differential equations with effective numerical method. The long-term dynamic behaviors predict where systems are heading after long-term evolution. We make some modification and transplant cell mapping methods to autonomous fractional differential equations. The mapping time duration of cell mapping is enlarged to deal with the long memory effect. Three illustrative examples, i.e. fractional Lotka-Volterra equation, fractional van der Pol oscillator and fractional Duffing equation, are studied with our revised generalized cell mapping method. We obtain long-term dynamics, such as attractors, basins of attraction, and saddles. Compared with some existing stability and numerical results, the validity of our method is verified. Furthermore, we find that the fractional order has its effect on the long-term dynamics of autonomous fractional differential equations.

Catheter-associated urinary tract infection.

PubMed

Tambyah, Paul A; Oon, Jolene

2012-08-01

Catheter-associated urinary tract infection (CAUTI) is the commonest nosocomial infection worldwide. Here we review the recent advances in the prevention of CAUTI. After more than 30 years, new guidelines were issued in 2008-2011 by the Infectious Diseases Society of America, Society for Healthcare Epidemiology of America, Healthcare Infection Control Practices Advisory Committee and European Association of Urology. These guidelines addressed novel technologies such as silver alloy or antimicrobial coatings on catheters, hydrophilic catheters, urethral stents, use of sealed catheter-tube junctions and antiinfective bladder irrigation. In addition, multiple trials have been published recently on the reduction of inappropriate urinary tract catheterization. Numerous strategies have been developed to reduce the incidence of CAUTI but few have proven effective. Reducing the inappropriate use of catheters and development of novel technologies targeted against these increasingly multidrug-resistant pathogens may be useful in the prevention of CAUTI in our vulnerable patients.

The Womanly World of Long Term Care: The Plight of the Long Term Care Worker. Gray Paper.

ERIC Educational Resources Information Center

Older Women's League, Washington, DC.

Long-term care workers (those who are paid to provide custodial care for long-term patients in nursing homes or at home) must care for a growing number of increasingly disabled or dependent persons. They are working for agencies and institutions under growing pressure to increase productivity. They face new training and competency requirements,…

Bacterial contamination of epidural catheters: microbiological examination of 502 epidural catheters used for postoperative analgesia.

PubMed

Steffen, Peter; Seeling, Wulf; Essig, Andreas; Stiepan, Erika; Rockemann, Michael Georg

2004-03-01

To investigate the frequency of bacterial colonization of epidural catheters used for postoperative pain treatment longer than 24 hours in abdominal, thoracic, or trauma surgery patients. Retrospective study. Intermediate care facility and general ward of a university hospital. 502 patients who received epidural catheters after abdominal, thoracic, or vascular surgery at our institution from January 1996 to December 2000. Placement of an epidural catheter, which was used for postoperative pain treatment, for more than 24 hours. The puncture site dressing included saturation each day with povidone-iodine. Microbiologic monitoring of epidural catheter tips and daily examination of puncture sites with regard to signs of inflammation took place. Four times daily patients were examined to check adequacy of pain treatment and neurologic deficits. Catheter tip cultures were positive in 29 patients (5.8%). Staphylococcus epidermidis was isolated in 22 cases (76%). No case of spinal epidural abscess was observed within 6 months after epidural catheterization. The average catheterization time was 5 days (quartile range: 4 to 6 days). Meticulous management ensures a relatively low level of bacterial contamination in epidural catheters applied for postoperative pain treatment greater than 5 days. Contamination rarely leads to spinal epidural infection.

[Infectious risk related to the formation of multi-species biofilms (Candida - bacteria) on peripheral vascular catheters].

PubMed

Seghir, A; Boucherit-Otmani, Z; Sari-Belkharroubi, L; Boucherit, K

2017-03-01

The Candida yeasts are the fourth leading cause of death from systemic infections, the risk may increase when the infection also involves bacteria. Yeasts and bacteria can adhere to medical implants, such as peripheral vascular catheters, and form a multicellular structures called "mixed biofilms" more resistant to antimicrobials agents. However, the formation of mixed biofilms on implants leads to long-term persistent infections because they can act as reservoirs of pathogens that have poorly understood interactions. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Measures for the reduction of sinter formations in tunnels

NASA Astrophysics Data System (ADS)

Harer, Gerhard

2017-09-01

A considerable part of the maintenance costs of tunnel structures is related to the inspection, maintenance and repair of the drainage system. The drainage system of tunnels is frequently clogged with Calcium precipitates. Cleaning and water conditioning are costintensive for operating companies. Apart from the direct costs associated with inspection, maintenance and repair works of the drainage system indirect costs are generated, such as by the blocking of the tunnel while inspection, maintenance or repair or by the reduction of the permitted operation speed. Sintering and clogging of the drainage systems is mainly caused by dissolution of cement minerals in concrete and mortar and/or by inadequate design and construction of the drainage system and/or grubby workmanship. With long-term studies and in-situ experiments in Austria traffic tunnels the specific input factors for sinter mechanism have been identified and appropriate counter measures could be defined. In particular modified mix designs for shotcretes and mortars have proven to bring a significant beneficial effect. By means of constructional measures and by the application of hardness stabilizers a further reduction of hard deposits inside the drainage system is achievable. The paper will deal with the specific aspects and will propose adequate counter measures.

Long-term studies of dopamine agonists.

PubMed

Hubble, Jean P

2002-02-26

Dopamine agonists have long been used as adjunctive therapy for the treatment of Parkinson's disease (PD). In more recent years these drugs have also been proved safe and effective as initial therapy in lieu of levodopa in the treatment of PD. Long-term levodopa therapy is associated with motor complications, including fluctuating response patterns and dyskinesia. By initially introducing a dopamine agonist as symptomatic drug therapy, it may be possible to postpone the use of levodopa and delay or prevent the development of motor complications. Recently, four clinical trials have explored this hypothesis by comparing the long-term response and side effects of levodopa with dopamine agonist therapy. The drugs studied have included ropinirole, pramipexole, cabergoline, and pergolide. In each of these projects, the occurrence of motor complications, such as wearing off and dyskinesia, was significantly less in the subjects assigned to initiation of therapy with a dopamine agonist. The addition of levodopa could be postponed by many months or even several years. Therefore, these long-term studies of dopamine agonists support the initiation of a dopamine agonist instead of levodopa in an effort to postpone levodopa-related motor complications. This therapeutic approach may be particularly appropriate in PD patients with a long treatment horizon on the basis of age and general good health. The extension phase of the long-term study comparing pramipexole with levodopa is ongoing, and follow-up information may help to establish the value of this treatment strategy.

Telemetric implantable pressure sensor for short- and long-term monitoring of intracranial pressure.

PubMed

Frischholz, M; Sarmento, L; Wenzel, M; Aquilina, K; Edwards, R; Coakham, H B

2007-01-01

Patients with hydrocephalus, idiopathic intracranial hypertension and head injury frequently require monitoring of intracranial pressure (ICP) and may need repeated episodes of monitoring months or years apart. The gold standard for measurement of ICP remains the external ventricular catheter. This is a fluid-filled catheter transducer system that allows regular recalibration and correction of zero drift by its position relative to a fixed anatomical reference. It also allows drainage of cerebrospinal fluid (CSF), providing a means of lowering the ICP. Several catheter tip transducer systems are currently in clinical use, including using strain gauges or fiber-optical pressure sensing techniques. In these devices, zero drift and calibration cannot be checked in vivo. All the ICP monitoring devices in current clinical use require a physical connection between the brain and the external environment. This is a source of infection and limits the duration of monitoring. A number of telemetric monitoring devices, in which data is in some way transmitted transcutaneously, have been developed over the last twenty years, but significant technical problems have precluded their use in routine clinical practice. All current ICP monitors are temporary percutaneous implanted devices. Placement of these devices carries significant morbidity, particularly infection. Patients undergoing repeated monitoring require multiple surgical procedures. Apart from decreasing the risk of infection in patients with severe head injury, the clinical value of an accurate telemetric ICP monitoring system which maintains its reliability over a long period of implantation is high.

The analysis of creep characteristics of the surrounding rock of the carbonaceous rock tunnel based on Singh-Mitchell model

NASA Astrophysics Data System (ADS)

Luo, Junhui; Mi, Decai; Ye, Qiongyao; Deng, Shengqiang; Zeng, Fuquan; Zeng, Yongjun

2018-01-01

Carbonaceous rock has the characteristics of easy disintegration, softening, swelling and environmental sensitivity, which belongs to soft surrounding rock, and the deformation during excavation and long-term stability of the surrounding rock of carbonaceous rock tunnel are common problems in the construction of carbonaceous rock tunnel. According to the above, the Monitor and measure the displacement, temperature and osmotic pressure of the surrounding carbonaceous rock of the tunnel of Guangxi Hebai highway. Then it based on the obtaining data to study the creep mechanism of surrounding rock using Singh-Mitchell model and predict the deformation of surrounding rock before the tunnel is operation. The results show that the Singh-Mitchell creep model can effectively analyse and predict the deformation development law of surrounding rock of tunnel without considering temperature and osmotic pressure, it can provide reference for the construction of carbonaceous rock tunnel and the measures to prevent and reinforce it..

Central venous catheter-related infections in patients receiving short-term hemodialysis therapy: incidence, associated factors, and microbiological aspects.

PubMed

Menegueti, Mayra Gonçalves; Betoni, Natália Cristina; Bellissimo-Rodrigues, Fernando; Romão, Elen Almeida

2017-01-01

Bloodstream infections are the second most common cause of death among patients on hemodialysis. This study aimed to evaluate the incidence of and risk factors associated with central venous catheter-related infections in patients undergoing hemodialysis, and to identify and characterize the type and antimicrobial susceptibility profiles of the primary microorganisms isolated during one year of follow-up. A prospective cohort study was conducted in 2014 in a hemodialysis referral center. We included 200 outpatients with acute kidney injury who had no permanent venous access. A nurse assessed the patients for signs of infection three times per week during dressing changes. The clinicopathologic characteristics of patients with and without local or systemic infection were compared. Fifty-five episodes of catheter-related infections occurred in 43 (22%) patients; 38 (69%) were bloodstream infections and 17 (31%) were local infections. Thirty-two (75%) patients with infection had femoral vein catheter placement. In total, 6,240 hemodialysis sessions were performed; the rates of primary bloodstream and local infection were 6.1 and 2.7 episodes per 1,000 patients on daily dialysis, respectively. In the univariate analysis, diabetes was significantly associated with the development of infection, while level of education, ethnicity, age, and sex were not. Gram-negative bacteria were primarily isolated from blood culture specimens (55% of samples). Of the Gram-negative isolates, 56% were resistant to the carbapenems. We identified a high incidence of catheter-related infections caused by resistant microorganisms in patients undergoing hemodialysis via central venous catheters.

Large eccentric laser angioplasty catheter

NASA Astrophysics Data System (ADS)

Taylor, Kevin D.; Reiser, Christopher

1997-05-01

In response to recent demand for increased debulking of large diameter coronary vascular segments, a large eccentric catheter for excimer laser coronary angioplasty has been developed. The outer tip diameter is 2.0 mm and incorporates approximately 300 fibers of 50 micron diameter in a monorail- type percutaneous catheter. The basic function of the device is to ablate a coronary atherosclerotic lesion with 308 nm excimer laser pulses, while passing the tip of the catheter through the lesion. By employing multiple passes through the lesion, rotating the catheter 90 degrees after each pass, we expect to create luminal diameters close to 3 mm with this device. Design characteristics, in-vitro testing, and initial clinical experience is presented.

Minilaparotomy salvage of malfunctioning catheters in peritoneal dialysis.

PubMed

Li, Jian-Ri; Cheng, Chi-Hung; Chiu, Kun-Yuan; Cheng, Chen-Li; Yang, Chi-Rei; Ho, Hao-Chung; Ko, Jiunn-Liang; Ou, Yen-Chuan

2013-01-01

Catheter malfunction is a common and significant complication during peritoneal dialysis (PD). We developed a minilaparotomy procedure to rescue malfunctioning catheters and to prevent recurrence of malfunction. From 2006 to 2011, 11 patients receiving PD had a malfunctioning catheter. In all patients, a 2-cm incision, 5 cm caudally to the previous peritoneal entry site was used to correct the malfunctioning catheter, with concomitant fixation of the catheter to the peritoneum. Catheter tip migration occurred in 7 patients, omental wrapping in 3, and blood clot obstruction in 1. The mean onset time to catheter malfunction was 197.5 days (range: 4 - 1270 days), and the mean operating time was 41 minutes (range: 35 - 56 minutes). There was no recurrence of catheter malfunction and no surgery-related peritonitis. Our minilaparotomy procedure is safe and feasible for the salvage of malfunctioning PD catheters.

Long Term TOA - M Data and Information

Atmospheric Science Data Center

2017-09-06

... A Long-Term TOA and Constrained Surface Radiation Budget Project A Long-Term TOA and Constrained Surface Readiation ... Budget Experiment (ERBE) and Clouds and the Earth's Radiant Energy System (CERES), that span nearly 30 years to date.   The ...

Safety and Long-Term Outcomes of Catheter Ablation of Atrial Fibrillation Using Magnetic Navigation versus Manual Conventional Ablation: A Propensity-Score Analysis.

PubMed

Adragão, Pedro Pulido; Cavaco, Diogo; Ferreira, António Miguel; Costa, Francisco Moscoso; Parreira, Leonor; Carmo, Pedro; Morgado, Francisco Bello; Santos, Katya Reis; Santos, Pedro Galvão; Carvalho, Maria Salomé; Durazzo, Anai; Marques, Hugo; Gonçalves, Pedro Araújo; Raposo, Luís; Mendes, Miguel

2016-03-01

Whether or not the potential advantages of using a magnetic navigation system (MNS) translate into improved outcomes in patients undergoing atrial fibrillation (AF) ablation is a question that remains unanswered. In this observational registry study, we used propensity-score matching to compare the outcomes of patients with symptomatic drug-refractory AF who underwent catheter ablation using MNS with the outcomes of those who underwent catheter ablation using conventional manual navigation. Among 1,035 eligible patients, 287 patients in each group had similar propensity scores and were included in the analysis. The primary efficacy outcome was the rate of AF relapse after a 3-month blanking period. At a mean follow-up of 2.6 ± 1.5 years, AF ablation with MNS was associated with a similar risk of AF relapse as compared with manual navigation (18.4% per year and 22.3% per year, respectively; hazard ratio 0.81, 95% CI 0.63-1.05; P = 0.108). Major complications occurred in two patients (0.7%) using MNS, and in six patients (2.1%) undergoing manually navigated ablation (P = 0.286). Fluoroscopy times were 21 ± 10 minutes in the manual navigation group, and 12 ± 9 minutes in the MNS group (P < 0.001), whereas total procedure times were 152 ± 52 minutes and 213 ± 58 minutes, respectively (P < 0.001). In this propensity-score matched comparison, magnetic navigation and conventional manual AF ablations seem to have similar relapse rates and a similar risk of complications. AF ablations with magnetic navigation take longer to perform but expose patients to significantly shorter fluoroscopy times. © 2015 Wiley Periodicals, Inc.

Long-term biological investigations in space.

PubMed

Lotz, R G; Fuchs, H; Bertsche, U

1975-01-01

Missions in space within the next two decades will be of longer duration than those carried out up to the present time, and the effects of such long-term flights on biological organisms are unknown. Results of biological experiments that have been performed to date cannot be extrapolated to results in future flights because of the unknown influence of adaptation over a long period of time. Prior experiments with Axolotl, fishes, and vertebrates by our research team (in part with sounding rockets) showed that these specimens did not appear to be suitable for long-term missions on which minimization of expense, technique, and energy is required. Subsequent investigations have shown the suitability of the leech (Hirudo medicinalis), which consumes blood of mammals up to ten times its own weight (1 g) and can live more than 2 years without further food supply. Emphasis in the experiments with Hirudo medicinalis is placed on metabolic rhythm and motility. Resorption and diffusion in tissue, development, and growth under long-term effects of cosmic proton radiation and zero-gravity are other focal points. The constancy of cellular life in the mature animals is a point in favor of these specimens. We have also taken into account the synergistic effects of the space environment on the problems just mentioned. The life-support system constructed for the leech has been tested successfully in four sounding rocket flights and, on that basis, has been prepared for a long-term mission. Long-term investigations out of the terrestrial biosphere will provide us with information concerning the degree of adaptation of certain physiological and biochemical functions and as to what extent biological readjustment or repair processes can occur under the specific stress conditions of space flight.

Embolization of renal angiomyolipomas: short-term and long-term outcomes, complications, and tumor shrinkage.

PubMed

Lee, Shen-Yang; Hsu, Hsiang-Hao; Chen, Yung-Chang; Huang, Chen-Chih; Wong, Yon-Cheong; Wang, Li-Jen; Chuang, Cheng-Keng; Yang, Chih-Wei

2009-11-01

This study retrospectively evaluated outcomes, complications, and tumor shrinkage in renal angiomyolipomas after transcatheter arterial embolization (TAE). All renal angiomyolipoma patients who underwent TAE between August 2000 and December 2008 and had short-term (long-term (>6 months) follow-up images were evaluated. Complications and tumor relapse after TAE were reviewed. The sizes of embolized tumors were measured to calculate size reductions and reduction rates after TAE. Differences in tumor size, size reduction, and reduction rate between different time points (pre-TAE, short-term follow-up, and long-term follow-up) and groups (completely and incompletely embolized) were determined. Eleven renal angiomyolipoma patients who had undergone TAE were included. Seven (63.6%) patients had postembolization syndrome and one had abscess formation following TAE. Two patients had a tumor relapse (18.2%). The mean tumor size was 8.57+/-2.66 cm on pre-TAE images. The mean size reduction was 3.1 cm (33.3%) and 3.8 cm (43.0%) at short-term and long-term follow-up. Tumor sizes differed significantly between pre-TAE and short-term (p=0.004) or long-term images (p=0.022) but not between short-term and long-term images (p=0.059). Results stratified by the completeness of embolization indicate that only the short-term size reduction rate differed significantly (p=0.025), while the long-term reduction rate and short- and long-term follow-up tumor size and size reduction were comparable between the two groups. In conclusion, selective TAE is effective for tumor shrinkage in most renal angiomyolipomas, with acceptable complication and relapse rates. Tumor shrinkage occurring within 6 months after TAE may reflect the long-term effect of TAE.

Reaction of long-lived radicals and vitamin C in γ-irradiated mammalian cells and their model system at 295 K. Tunneling reaction in biological system

NASA Astrophysics Data System (ADS)

Matsumoto, Takuro; Miyazaki, Tetsuo; Kosugi, Yoshio; Kumada, Takayuki; Koyama, Sinji; Kodama, Seiji; Watanabe, Masami

1997-05-01

When golden hamster embryo (GHE) cells or concentrated albumin solution (0.1 kg dm -3) that is a model system of cells is irradiated with γ-rays at 295 K, organic radicals produced can be observed by ESR. The organic radicals survive at both 295 and 310 K for such a long time as 20 h. The long-lived radicals in GHE cells and the albumin solution react with vitamin C by the rate constants of 0.007 dm 3 mol -1 s -1 and 0.014 dm 3 mol -1 s -1, respectively. The long-lived radicals in human cells cause gene mutation, which is suppressed by addition of vitamin C. The isotope effect on the rate constant ( k) for the reaction of the long-lived radicals and vitamin C has been studied in the albumin solution by use of protonated vitamin C and deuterated vitamin C. The isotope effect ( kH/ kD) was more than 20 ≈ 50 and was interpreted in terms of tunneling reaction.

21 CFR 876.5130 - Urological catheter and accessories.

Code of Federal Regulations, 2010 CFR

2010-04-01

... device that is inserted through the urethra and used to pass fluids to or from the urinary tract. This..., coude catheters, balloon retention type catheters, straight catheters, upper urinary tract catheters...

21 CFR 870.1210 - Continuous flush catheter.

Code of Federal Regulations, 2014 CFR

2014-04-01

...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Diagnostic Devices § 870.1210 Continuous flush catheter. (a) Identification. A continuous flush catheter is an attachment to a catheter-transducer system...

21 CFR 870.1210 - Continuous flush catheter.

Code of Federal Regulations, 2012 CFR

2012-04-01

...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Diagnostic Devices § 870.1210 Continuous flush catheter. (a) Identification. A continuous flush catheter is an attachment to a catheter-transducer system...

21 CFR 870.1210 - Continuous flush catheter.

Code of Federal Regulations, 2013 CFR

2013-04-01

...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Diagnostic Devices § 870.1210 Continuous flush catheter. (a) Identification. A continuous flush catheter is an attachment to a catheter-transducer system...

Prospective study of catheter-related central vein thrombosis in home parenteral nutrition patients with benign disease using serial venous Doppler ultrasound.

PubMed

Cuerda, Cristina; Joly, Francisca; Corcos, Olivier; Concejo, Javier; Puiggrós, Carolina; Gil, Carmen; Pironi, Loris

2016-02-01

Catheter-related central vein thrombosis (CRVT) is a severe complication of home parenteral nutrition (HPN) that may be clinically manifest or subclinical. The aims of the study were to prospectively investigate the incidence of CRVT in patients on HPN with benign disease and determine the influence of different variables on this complication. A prospective, multicentre, observational study in the Home Artificial Nutrition-Chronic Intestinal Failure ESPEN group was performed. Patients with benign disease starting HPN or already on HPN after the insertion of a new catheter, were recruited and followed up with Color Doppler Duplex Sonography (CDDS) evaluations at baseline, 1 week, 3, 6 and 12 months after catheter insertion. Fisher's exact test was used to calculate the association of different variables (related to the patient, type of catheter, vascular access, insertion method, catheter care and anticoagulant treatment) with CRVT events. Sixty-two patients (31 males, 31 females) aged 50 ± 19 (19-83) years were included and followed for a median 363 days, with an Inter Quartile Range of 180-365 days, and a total of 16,186 catheter-days. Six patients had previous CRVT and 16 had history of thromboembolic disease (pulmonary and mesenteric). Forty one patients were receiving anticoagulant treatment. Fifty two patients had tunneled catheters and 10 implanted ports. Two patients had symptomatic thrombosis at 3 and 12 months of follow-up (2 and 3 weeks after normal routine CDDS evaluation). The incidence of CRVT was 0.045/catheter/year. CRVT was not significantly associated with any of the variables analyzed. The incidence of CRVT in patients on HPN for benign disease followed by CDDS is low in the first year of catheterization. We did not observe any case of asymptomatic CRVT. Based on our data, CDDS seems to have low effectiveness as a screening tool for CRVT in asymptomatic patients on HPN with benign disease. Copyright © 2015 Elsevier Ltd and European Society for

Anti-fouling strategies for central venous catheters

PubMed Central

Albadawi, Hassan; Patel, Nikasha; Khademhosseini, Ali; Zhang, Yu Shrike; Naidu, Sailendra; Knuttinen, Grace; Oklu, Rahmi

2017-01-01

Central venous catheters (CVCs) are ubiquitous in the healthcare industry and carry two common complications, catheter related infections and occlusion, particularly by thrombus. Catheter-related bloodstream infections (CRBSI) are an important cause of nosocomial infections that increase patient morbidity, mortality, and hospital cost. Innovative design strategies for intravenous catheters can help reduce these preventable infections. Antimicrobial coatings can play a major role in preventing disease. These coatings can be divided into two major categories: drug eluting and non-drug eluting. Much of these catheter designs are targeted at preventing the formation of microbial biofilms that make treatment of CRBSI nearly impossible without removal of the intravenous device. Exciting developments in catheter impregnation with antibiotics as well as nanoscale surface design promise innovative changes in the way that physicians manage intravenous catheters. Occlusion of a catheter renders the catheter unusable and is often treated by tissue plasminogen activator administration or replacement of the line. Prevention of this complication requires a thorough understanding of the mechanisms of platelet aggregation, signaling and cross-linking. This article will look at the advances in biomaterial design specifically drug eluting, non-drug eluting, lubricious coatings and micropatterning as well as some of the characteristics of each as they relate to CVCs. PMID:29399528

Anti-fouling strategies for central venous catheters.

PubMed

Wallace, Alex; Albadawi, Hassan; Patel, Nikasha; Khademhosseini, Ali; Zhang, Yu Shrike; Naidu, Sailendra; Knuttinen, Grace; Oklu, Rahmi