Sample records for af noninvasiv ventilation

  1. Temperature-controlled airflow ventilation in operating rooms compared with laminar airflow and turbulent mixed airflow.

    PubMed

    Alsved, M; Civilis, A; Ekolind, P; Tammelin, A; Andersson, A Erichsen; Jakobsson, J; Svensson, T; Ramstorp, M; Sadrizadeh, S; Larsson, P-A; Bohgard, M; Šantl-Temkiv, T; Löndahl, J

    2018-02-01

    To evaluate three types of ventilation systems for operating rooms with respect to air cleanliness [in colony-forming units (cfu/m 3 )], energy consumption and comfort of working environment (noise and draught) as reported by surgical team members. Two commonly used ventilation systems, vertical laminar airflow (LAF) and turbulent mixed airflow (TMA), were compared with a newly developed ventilation technique, temperature-controlled airflow (T c AF). The cfu concentrations were measured at three locations in an operating room during 45 orthopaedic procedures: close to the wound (<40cm), at the instrument table and peripherally in the room. The operating team evaluated the comfort of the working environment by answering a questionnaire. LAF and T c AF, but not TMA, resulted in less than 10cfu/m 3 at all measurement locations in the room during surgery. Median values of cfu/m 3 close to the wound (250 samples) were 0 for LAF, 1 for T c AF and 10 for TMA. Peripherally in the room, the cfu concentrations were lowest for T c AF. The cfu concentrations did not scale proportionally with airflow rates. Compared with LAF, the power consumption of T c AF was 28% lower and there was significantly less disturbance from noise and draught. T c AF and LAF remove bacteria more efficiently from the air than TMA, especially close to the wound and at the instrument table. Like LAF, the new T c AF ventilation system maintained very low levels of cfu in the air, but T c AF used substantially less energy and provided a more comfortable working environment than LAF. This enables energy savings with preserved air quality. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Estimation of energy requirements for mechanically ventilated, critically ill patients using nutritional status

    PubMed Central

    Kan, Mee-Nin; Chang, Han-Hsin; Sheu, Woei-Fen; Cheng, Chien-Hsiang; Lee, Bor-Jen; Huang, Yi-Chia

    2003-01-01

    Background There is very little information on what is considered an adequate energy intake for mechanically ventilated, critically ill patients. The purpose of the present study was to determine this energy requirement by making use of patients' nutritional status. Methods The study was conducted in a multidisciplinary intensive care unit of Taichung Veterans General Hospital, Taiwan. Patients were hemodynamically stable and not comatose, and were requiring at least 7 days of mechanical ventilation. Fifty-four patients successfully completed this study. The resting energy expenditure was measured using indirect calorimetry. The total energy requirement was considered 120% of the measured energy expenditure. The daily nutrient intake was recorded. Nutritional status was assessed using single and multiple parameters, nitrogen balance, and medical records, and was performed within 24 hours of admission and after 7 days in the intensive care unit. Results Fifteen patients were being underfed (<90% of total energy requirement), 20 patients were in the appropriate feeding (AF) group (within ± 10% of total energy requirement), and 19 patients received overfeeding (>110% of total energy requirement). Patients in the underfeeding group received only 68.3% of their energy requirement, while the overfeeding group patients received up to 136.5% of their required calories. Only patients in the AF group had a positive nitrogen balance (0.04 ± 5.1) on day 7. AF group patients had a significantly higher Nutritional Risk Index value at day 7 than at day 1. Conclusion AF patients had more improvement in nutritional status than patients in the other feeding groups. To provide at least 120% of the resting energy expenditure seemed adequate to meet the caloric energy needs of hemodynamically stable, mechanically ventilated, critically ill patients. PMID:12974978

  3. Ventilation and ventilators.

    PubMed

    Hayes, B

    1982-01-01

    The history of ventilation is reviewed briefly and recent developments in techniques of ventilation are discussed. Operating features of ventilators have changed in the past few years, partly as the result of clinical progress; yet, technology appears to have outstripped the clinician's ability to harness it most effectively. Clinical discipline and training of medical staff in the use of ventilators could be improved. The future is promising if clinician and designer can work together closely. Ergonomics of ventilators and their controls and the provision of alarms need special attention. Microprocessors are likely to feature prominently in the next generation of designs.

  4. International trends in clinical characteristics and oral anticoagulation treatment for patients with atrial fibrillation: Results from the GARFIELD-AF, ORBIT-AF I, and ORBIT-AF II registries.

    PubMed

    Steinberg, Benjamin A; Gao, Haiyan; Shrader, Peter; Pieper, Karen; Thomas, Laine; Camm, A John; Ezekowitz, Michael D; Fonarow, Gregg C; Gersh, Bernard J; Goldhaber, Samuel; Haas, Sylvia; Hacke, Werner; Kowey, Peter R; Ansell, Jack; Mahaffey, Kenneth W; Naccarelli, Gerald; Reiffel, James A; Turpie, Alexander; Verheugt, Freek; Piccini, Jonathan P; Kakkar, Ajay; Peterson, Eric D; Fox, Keith A A

    2017-12-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia in the world. We aimed to provide comprehensive data on international patterns of AF stroke prevention treatment. Demographics, comorbidities, and stroke risk of the patients in the GARFIELD-AF (n=51,270), ORBIT-AF I (n=10,132), and ORBIT-AF II (n=11,602) registries were compared (overall N=73,004 from 35 countries). Stroke prevention therapies were assessed among patients with new-onset AF (≤6 weeks). Patients from GARFIELD-AF were less likely to be white (63% vs 89% for ORBIT-AF I and 86% for ORBIT-AF II) or have coronary artery disease (19% vs 36% and 27%), but had similar stroke risk (85% CHA 2 DS 2 -VASc ≥2 vs 91% and 85%) and lower bleeding risk (11% with HAS-BLED ≥3 vs 24% and 15%). Oral anticoagulant use was 46% and 57% for patients with a CHA 2 DS 2 -VASc=0 and 69% and 87% for CHA 2 DS 2 -VASc ≥2 in GARFIELD-AF and ORBIT-AF II, respectively, but with substantial geographic heterogeneity in use of oral anticoagulant (range: 31%-93% [GARFIELD-AF] and 66%-100% [ORBIT-AF II]). Among patients with new-onset AF, non-vitamin K antagonist oral anticoagulant use increased over time to 43% in 2016 for GARFIELD-AF and 71% for ORBIT-AF II, whereas use of antiplatelet monotherapy decreased from 36% to 17% (GARFIELD-AF) and 18% to 8% (ORBIT-AF I and II). Among new-onset AF patients, non-vitamin K antagonist oral anticoagulant use has increased and antiplatelet monotherapy has decreased. However, anticoagulation is used frequently in low-risk patients and inconsistently in those at high risk of stroke. Significant geographic variability in anticoagulation persists and represents an opportunity for improvement. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  5. Anaesthesia ventilators.

    PubMed

    Jain, Rajnish K; Swaminathan, Srinivasan

    2013-09-01

    Anaesthesia ventilators are an integral part of all modern anaesthesia workstations. Automatic ventilators in the operating rooms, which were very simple with few modes of ventilation when introduced, have become very sophisticated with many advanced ventilation modes. Several systems of classification of anaesthesia ventilators exist based upon various parameters. Modern anaesthesia ventilators have either a double circuit, bellow design or a single circuit piston configuration. In the bellows ventilators, ascending bellows design is safer than descending bellows. Piston ventilators have the advantage of delivering accurate tidal volume. They work with electricity as their driving force and do not require a driving gas. To enable improved patient safety, several modifications were done in circle system with the different types of anaesthesia ventilators. Fresh gas decoupling is a modification done in piston ventilators and in descending bellows ventilator to reduce th incidence of ventilator induced volutrauma. In addition to the conventional volume control mode, modern anaesthesia ventilators also provide newer modes of ventilation such as synchronised intermittent mandatory ventilation, pressure-control ventilation and pressure-support ventilation (PSV). PSV mode is particularly useful for patients maintained on spontaneous respiration with laryngeal mask airway. Along with the innumerable benefits provided by these machines, there are various inherent hazards associated with the use of the ventilators in the operating room. To use these workstations safely, it is important for every Anaesthesiologist to have a basic understanding of the mechanics of these ventilators and breathing circuits.

  6. Aspergillus fumigatus (Af) Hydroxamate Siderophores Protect Formation of Af Biofilms from the Pseudomonas aeruginosa (Pa) Product Pyoverdine

    PubMed Central

    Sass, Gabriele; Stevens, David A

    2017-01-01

    Abstract Background Pa and Af are pathogens frequently found together in airways of immunocompromised patients and patients with cystic fibrosis (CF). Hence, interactions of Pa and Af require understanding. Both Pa and Af are crucially dependent on the availability of iron, and therefore are competitors in their microenvironment. We have shown, using deletion mutants of Pa, that the Pa siderophore pyoverdine, the dominant Pa inhibitor of Af, interferes with Af biofilms by iron chelation, and denial of iron to the fungus. Methods Protective compounds in Af supernatants were evaluated using assays for the quantification of Af biofilm metabolism by XTT measurement, spectrometric pyoverdine measurement, as well as Chrome Azorole S (CAS) assay for the determination of siderophore production. Results Here we provide evidence that whereas iron usage by Af promotes pyoverdine production by Pa, Af has developed a defense mechanism against anti-fungal pyoverdine effects. The ability of Af to produce hydroxamate siderophores, and shed these into the surrounding medium, where they sequester and transport iron, is a key factor for Af self-defense against Pa. Under low iron conditions, such as in the presence of high amounts of the Pa siderophore pyoverdine, siderophore-bound iron is then fed to Af, protecting the fungus from iron starvation. Af with a deletion mutation in sidA, a gene essential for the production of hydroxamate siderophores, was significantly more sensitive to Pa supernatants, as well as pure pyoverdine, than wild-type Af. Af supernatants, produced in the presence of celastrol, an inhibitor of SidA-generated biosynthesis of siderophores, or produced by the sidA mutant, were not able to protect Af from iron starvation. Conclusion Interference with the iron-dependent Af self-defense mechanism might represent a new approach for therapy against aspergillosis. Disclosures All authors: No reported disclosures.

  7. Evaluation of ventilators for mouthpiece ventilation in neuromuscular disease.

    PubMed

    Khirani, Sonia; Ramirez, Adriana; Delord, Vincent; Leroux, Karl; Lofaso, Frédéric; Hautot, Solène; Toussaint, Michel; Orlikowski, David; Louis, Bruno; Fauroux, Brigitte

    2014-09-01

    Daytime mouthpiece ventilation is a useful adjunct to nocturnal noninvasive ventilation (NIV) in patients with neuromuscular disease. The aims of the study were to analyze the practice of mouthpiece ventilation and to evaluate the performance of ventilators for mouthpiece ventilation. Practice of mouthpiece ventilation was assessed by a questionnaire, and the performance of 6 home ventilators with mouthpiece ventilation was assessed in a bench test using 24 different conditions per ventilator: 3 mouthpieces, a child and an adult patient profile, and 4 ventilatory modes. Questionnaires were obtained from 30 subjects (mean age 33 ± 11 y) using NIV for 12 ± 7 y. Fifteen subjects used NIV for > 20 h/day, and 11 were totally ventilator-dependent. The subject-reported benefits of mouthpiece ventilation were a reduction in dyspnea (73%) and fatigue (93%) and an improvement in speech (43%) and eating (27%). The bench study showed that none of the ventilators, even those with mouthpiece ventilation software, were able to deliver mouthpiece ventilation without alarms and/or autotriggering in each condition. Alarms and/or ineffective triggering or autotriggering were observed in 135 of the 198 conditions. The occurrence of alarms was more common with a large mouthpiece without a filter compared to a small mouthpiece with a filter (P < .001), but it was not related to the patient profile, the ventilatory mode, or the type of ventilator. Subjects are satisfied with mouthpiece ventilation. Alarms are common with home ventilators, although less common in those with mouthpiece ventilation software. Improvements in home ventilators are needed to facilitate the expansion of mouthpiece ventilation. Copyright © 2014 by Daedalus Enterprises.

  8. Health Information in Somali (Af-Soomaali )

    MedlinePlus

    ... Af-Soomaali (Somali) Bilingual PDF Health Information Translations Pendulum Exercises for Shoulder - Af-Soomaali (Somali) Bilingual PDF ... Af-Soomaali (Somali) Bilingual PDF Health Information Translations Pendulum Exercises for Shoulder - Af-Soomaali (Somali) Bilingual PDF ...

  9. Respiratory system loop gain in normal men and women measured with proportional-assist ventilation.

    PubMed

    Wellman, Andrew; Malhotra, Atul; Fogel, Robert B; Edwards, Jill K; Schory, Karen; White, David P

    2003-01-01

    We hypothesized that increased chemical control instability (CCI) in men could partially explain the male predominance in obstructive sleep apnea (OSA). CCI was assessed by sequentially increasing respiratory control system loop gain (LG) with proportional-assist ventilation (PAV) in 10 men (age 24-48 yr) and 9 women (age 22-36 yr) until periodic breathing or awakening occurred. Women were studied in both the follicular and luteal phases of the menstrual cycle. The amount by which PAV amplified LG was quantified from the tidal volume amplification factor [(VtAF) assisted tidal volume/unassisted tidal volume]. LG was calculated as the inverse of the VtAF occurring at the assist level immediately preceding the emergence of periodic breathing (when LG x VtAF = 1). Only 1 of 10 men and 2 of 9 women developed periodic breathing with PAV. The rest were resistant to periodic breathing despite moderately high levels of PAV amplification. We conclude that LG is low in the majority of normal men and women and that higher volume amplification factors are needed to determine whether gender differences exist in this low range.

  10. Bench performance of ventilators during simulated paediatric ventilation.

    PubMed

    Park, M A J; Freebairn, R C; Gomersall, C D

    2013-05-01

    This study compares the accuracy and capabilities of various ventilators using a paediatric acute respiratory distress syndrome lung model. Various compliance settings and respiratory rate settings were used. The study was done in three parts: tidal volume and FiO2 accuracy; pressure control accuracy and positive end-expiratory pressure (PEEP) accuracy. The parameters set on the ventilator were compared with either or both of the measured parameters by the test lung and the ventilator. The results revealed that none of the ventilators could consistently deliver tidal volumes within 1 ml/kg of the set tidal volume, and the discrepancy between the delivered volume and the volume measured by the ventilator varied greatly. The target tidal volume was 8 ml/kg, but delivered tidal volumes ranged from 3.6-11.4 ml/kg and the volumes measured by the ventilator ranged from 4.1-20.6 ml/kg. All the ventilators maintained pressure within 20% of the set pressure, except one ventilator which delivered pressures of up to 27% higher than the set pressure. Two ventilators maintained PEEP within 10% of the prescribed PEEP. The majority of the readings were also within 10%. However, three ventilators delivered, at times, PEEPs over 20% higher. In conclusion, as lung compliance decreases, especially in paediatric patients, some ventilators perform better than others. This study highlights situations where ventilators may not be able to deliver, nor adequately measure, set tidal volumes, pressure, PEEP or FiO2.

  11. [Anesthesia ventilators].

    PubMed

    Otteni, J C; Beydon, L; Cazalaà, J B; Feiss, P; Nivoche, Y

    1997-01-01

    To review anaesthesia ventilators in current use in France by categories of ventilators. References were obtained from computerized bibliographic search. (Medline), recent review articles, the library of the service and personal files. Anaesthesia ventilators can be allocated into three groups, depending on whether they readminister expired gases or not or allow both modalities. Contemporary ventilators provide either constant volume ventilation, or constant pressure ventilation, with or without a pressure plateau. Ventilators readministering expired gases after CO2 absorption, or closed circuit ventilators, are either of a double- or a single-circuit design. Double-circuit ventilators, or pneumatical bag or bellows squeezers, or bag-in-bottle or bellows-in-bottle (or box) ventilators, consist of a primary, or driving circuit (bottle or box) and a secondary or patient circuit (including a bag or a bellows or membrane chambers). Bellows-in-bottle ventilators have either standing bellows ascending at expiration, or hanging bellows, descending at expiration. Ascending bellows require a positive pressure of about 2 cmH2O throughout exhalation to allow the bellows to refill. The expired gas volume is a valuable indicator for leak and disconnection. Descending bellows generate a slight negative pressure during exhalation. In case of leak or disconnection they aspirate ambient air and cannot act therefore as an indicator for integrity of the circuit and the patient connection. Closed circuit ventilators with a single-circuit (patient circuit) include a insufflating device consisting either in a bellows or a cylinder with a piston, operated by a electric or pneumatic motor. As the hanging bellows of the double circuit ventilators, they generate a slight negative pressure during exhalation and aspirate ambient air in case of leak or disconnection. Ventilators not designed for the readministration of expired gases, or open circuit ventilators, are generally stand

  12. Topological ferrimagnetic behaviours of coordination polymers containing manganese(II) chains with mixed azide and carboxylate bridges and alternating F/AF/AF'/AF'/AF interactions.

    PubMed

    Wang, Yan-Qin; Liu, Hou-Ting; Qi, Yan; Gao, En-Qing

    2014-08-21

    Two Mn(ii) complexes with azide and a new zwitterionic tetracarboxylate ligand 1,2,4,5-tetrakis(4-carboxylatopyridinium-1-methylene)benzene (L(1)), {[Mn5(L(1))2(N3)8(OH)2]·12H2O}n () and {[Mn5(L(1))2(N3)8(H2O)2](ClO4)2·6H2O}n (), have been synthesized and characterized crystallographically and magnetically. and contain similar alternating chains constructed by azide and carboxylate bridges. The independent sets of bridges alternate in an ABCCB sequence between adjacent Mn(ii) ions: (EO-N3)2 double bridges (EO = end-on) (denoted as A), [(EO-N3)(OCO)2] triple bridges (denoted as B) and [(EO-N3)(OCO)] double bridges (denoted as C). The alternating chains are interlinked into 2D coordination networks by the tetrapyridinium spacers. Magnetic studies demonstrate that the magnetic coupling through the double EO azide bridges is ferromagnetic and that through mixed azide/carboxylate bridges is antiferromagnetic. The unprecedented F/AF/AF'/AF'/AF coupling sequence along the chain dictates an uncompensated ground spin state (S = 5/2 per Mn5 unit) and leads to one-dimensional topological ferrimagnetism, which features a minimum in the χT versus T plot.

  13. Complex Transcriptional Control of the Antibiotic Regulator afsS in Streptomyces: PhoP and AfsR Are Overlapping, Competitive Activators▿

    PubMed Central

    Santos-Beneit, Fernando; Rodríguez-García, Antonio; Martín, Juan F.

    2011-01-01

    The afsS gene of several Streptomyces species encodes a small sigma factor-like protein that acts as an activator of several pathway-specific regulatory genes (e.g., actII-ORF4 and redD in Streptomyces coelicolor). The two pleiotropic regulators AfsR and PhoP bind to overlapping sequences in the −35 region of the afsS promoter and control its expression. Using mutated afsS promoters containing specific point mutations in the AfsR and PhoP binding sequences, we proved that the overlapping recognition sequences for AfsR and PhoP are displaced by 1 nucleotide. Different nucleotide positions are important for binding of AfsR or PhoP, as shown by electrophoretic mobility shift assays and by reporter studies using the luxAB gene coupled to the different promoters. Mutant promoter M5 (with a nucleotide change at position 5 of the consensus box) binds AfsR but not PhoP with high affinity (named “superAfsR”). Expression of the afsS gene from this promoter led to overproduction of actinorhodin. Mutant promoter M16 binds PhoP with extremely high affinity (“superPhoP”). Studies with ΔafsR and ΔphoP mutants (lacking AfsR and PhoP, respectively) showed that both global regulators are competitive transcriptional activators of afsS. AfsR has greater influence on expression of afsS than PhoP, as shown by reverse transcriptase PCR (RT-PCR) and promoter reporter (luciferase) studies. These two high-level regulators appear to integrate different nutritional signals (particularly phosphate limitation sensed by PhoR), S-adenosylmethionine, and other still unknown environmental signals (leading to AfsR phosphorylation) for the AfsS-mediated control of biosynthesis of secondary metabolites. PMID:21378195

  14. Initial mechanical ventilator settings and lung protective ventilation in the ED.

    PubMed

    Wilcox, Susan R; Richards, Jeremy B; Fisher, Daniel F; Sankoff, Jeffrey; Seigel, Todd A

    2016-08-01

    Mechanical ventilation with low tidal volumes has been shown to improve outcomes for patients both with and without acute respiratory distress syndrome. This study aims to characterize mechanically ventilated patients in the emergency department (ED), describe the initial ED ventilator settings, and assess for associations between lung protective ventilation strategies in the ED and outcomes. This was a multicenter, prospective, observational study of mechanical ventilation at 3 academic EDs. We defined lung protective ventilation as a tidal volume of less than or equal to 8 mL/kg of predicted body weight and compared outcomes for patients ventilated with lung protective vs non-lung protective ventilation, including inhospital mortality, ventilator days, intensive care unit length of stay, and hospital length of stay. Data from 433 patients were analyzed. Altered mental status without respiratory pathology was the most common reason for intubation, followed by trauma and respiratory failure. Two hundred sixty-one patients (60.3%) received lung protective ventilation, but most patients were ventilated with a low positive end-expiratory pressure, high fraction of inspired oxygen strategy. Patients were ventilated in the ED for a mean of 5 hours and 7 minutes but had few ventilator adjustments. Outcomes were not significantly different between patients receiving lung protective vs non-lung protective ventilation. Nearly 40% of ED patients were ventilated with non-lung protective ventilation as well as with low positive end-expiratory pressure and high fraction of inspired oxygen. Despite a mean ED ventilation time of more than 5 hours, few patients had adjustments made to their ventilators. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. [Lung protective ventilation. Ventilatory modes and ventilator parameters].

    PubMed

    Schädler, Dirk; Weiler, Norbert

    2008-06-01

    Mechanical ventilation has a considerable potential for injuring the lung tissue. Therefore, attention has to be paid to the proper choice of ventilatory mode and settings to secure lung-protective ventilation whenever possible. Such ventilator strategy should account for low tidal volume ventilation (6 ml/kg PBW), limited plateau pressure (30 to 35 cm H2O) and positive end-expiratory pressure (PEEP). It is unclear whether pressure controlled or volume controlled ventilation with square flow profile is beneficial. The adjustment of inspiration and expiration time should consider the actual breathing mechanics and anticipate the generation of intrinsic PEEP. Ventilatory modes with the possibility of supporting spontaneous breathing should be used as soon as possible.

  16. Variable mechanical ventilation

    PubMed Central

    Fontela, Paula Caitano; Prestes, Renata Bernardy; Forgiarini Jr., Luiz Alberto; Friedman, Gilberto

    2017-01-01

    Objective To review the literature on the use of variable mechanical ventilation and the main outcomes of this technique. Methods Search, selection, and analysis of all original articles on variable ventilation, without restriction on the period of publication and language, available in the electronic databases LILACS, MEDLINE®, and PubMed, by searching the terms "variable ventilation" OR "noisy ventilation" OR "biologically variable ventilation". Results A total of 36 studies were selected. Of these, 24 were original studies, including 21 experimental studies and three clinical studies. Conclusion Several experimental studies reported the beneficial effects of distinct variable ventilation strategies on lung function using different models of lung injury and healthy lungs. Variable ventilation seems to be a viable strategy for improving gas exchange and respiratory mechanics and preventing lung injury associated with mechanical ventilation. However, further clinical studies are necessary to assess the potential of variable ventilation strategies for the clinical improvement of patients undergoing mechanical ventilation. PMID:28444076

  17. Interactive simulation system for artificial ventilation on the internet: virtual ventilator.

    PubMed

    Takeuchi, Akihiro; Abe, Tadashi; Hirose, Minoru; Kamioka, Koichi; Hamada, Atsushi; Ikeda, Noriaki

    2004-12-01

    To develop an interactive simulation system "virtual ventilator" that demonstrates the dynamics of pressure and flow in the respiratory system under the combination of spontaneous breathing, ventilation modes, and ventilator options. The simulation system was designed to be used by unexperienced health care professionals as a self-training tool. The system consists of a simulation controller and three modules: respiratory, spontaneous breath, and ventilator. The respiratory module models the respiratory system by three resistances representing the main airway, the right and left lungs, and two compliances also representing the right and left lungs. The spontaneous breath module generates inspiratory negative pressure produced by a patient. The ventilator module generates driving force of pressure or flow according to the combination of the ventilation mode and options. These forces are given to the respiratory module through the simulation controller. The simulation system was developed using HTML, VBScript (3000 lines, 100 kB) and ActiveX control (120 kB), and runs on Internet Explorer (5.5 or higher). The spontaneous breath is defined by a frequency, amplitude and inspiratory patterns in the spontaneous breath module. The user can construct a ventilation mode by setting a control variable, phase variables (trigger, limit, and cycle), and options. Available ventilation modes are: controlled mechanical ventilation (CMV), continuous positive airway pressure, synchronized intermittent mandatory ventilation (SIMV), pressure support ventilation (PSV), SIMV + PSV, pressure-controlled ventilation (PCV), pressure-regulated volume control (PRVC), proportional assisted ventilation, mandatory minute ventilation (MMV), bilevel positive airway pressure (BiPAP). The simulation system demonstrates in a graph and animation the airway pressure, flow, and volume of the respiratory system during mechanical ventilation both with and without spontaneous breathing. We developed a web

  18. Impact of Room Ventilation Rates on Mouse Cage Ventilation and Microenvironment.

    PubMed

    Reeb, Carolyn K.; Jones, Robert B.; Bearg, David W.; Bedigian, Hendrick; Paigen, Beverly

    1997-01-01

    To assess the impact of room ventilation on animal cage microenvironment, intracage ventilation rate, temperature, humidity, and concentrations of carbon dioxide and ammonia were monitored in nonpressurized, bonnet-topped mouse cages. Cages on the top, middle, and bottom rows of a mouse rack were monitored at room ventilation rates of 0, 5, 10, and 20 air changes/h (ACH). Ventilation inside the animal cage increased somewhat from 12.8 to 18.9 ACH as room ventilation rate in- creased from 0 to 20 ACH, but the differences were not statistically significant, and most of the increase occurred in cages in the top row nearest to the fresh air supply. Cages containing mice had ventilation rate between 10 and 15 ACH even when room ventilation was reduced to 0 ACH; this ventilation is a result of the thermal heat load of the mice. After 6 days of soiled bedding, intracage ammonia concentration was c 3 ppm at all room ventilation rates and was not affected by increasing room ventilation. Temperature inside cages did not change with increasing ventilation. Humidity inside cages significantly decreased with increasing ventilation, from 55% relative humidity at 5 ACH to 36% relative humidity at 20 ACH. Carbon dioxide concentration decreased from 2,500 ppm to 1,900 ppm when ventilation rate increased from 5 ACH to 10 ACH, but no further significant decrease was observed at 20 ACH. In conclusion, increasing the room ventilation rate higher than 5 ACH did not result in significant improvements in the cage microenvironment.

  19. AF4 and AF4N protein complexes: recruitment of P-TEFb kinase, their interactome and potential functions

    PubMed Central

    Scholz, Bastian; Kowarz, Eric; Rössler, Tanja; Ahmad, Khalil; Steinhilber, Dieter; Marschalek, Rolf

    2015-01-01

    AF4/AFF1 and AF5/AFF4 are the molecular backbone to assemble “super-elongation complexes” (SECs) that have two main functions: (1) control of transcriptional elongation by recruiting the positive transcription elongation factor b (P-TEFb = CyclinT1/CDK9) that is usually stored in inhibitory 7SK RNPs; (2) binding of different histone methyltransferases, like DOT1L, NSD1 and CARM1. This way, transcribed genes obtain specific histone signatures (e.g. H3K79me2/3, H3K36me2) to generate a transcriptional memory system. Here we addressed several questions: how is P-TEFb recruited into SEC, how is the AF4 interactome composed, and what is the function of the naturally occuring AF4N protein variant which exhibits only the first 360 amino acids of the AF4 full-length protein. Noteworthy, shorter protein variants are a specific feature of all AFF protein family members. Here, we demonstrate that full-length AF4 and AF4N are both catalyzing the transition of P-TEFb from 7SK RNP to their N-terminal domain. We have also mapped the protein-protein interaction network within both complexes. In addition, we have first evidence that the AF4N protein also recruits TFIIH and the tumor suppressor MEN1. This indicate that AF4N may have additional functions in transcriptional initiation and in MEN1-dependend transcriptional processes. PMID:26171280

  20. Noninvasive ventilation.

    PubMed

    Rabatin, J T; Gay, P C

    1999-08-01

    Noninvasive ventilation refers to the delivery of assisted ventilatory support without the use of an endotracheal tube. Noninvasive positive pressure ventilation (NPPV) can be delivered by using a volume-controlled ventilator, a pressure-controlled ventilator, a bilevel positive airway pressure ventilator, or a continuous positive airway pressure device. During the past decade, there has been a resurgence in the use of noninvasive ventilation, fueled by advances in technology and clinical trials evaluating its use. Several manufacturers produce portable devices that are simple to operate. This review describes the equipment, techniques, and complications associated with NPPV and also the indications for both short-term and long-term applications. NPPV clearly represents an important addition to the techniques available to manage patients with respiratory failure. Future clinical trials evaluating its many clinical applications will help to define populations of patients most apt to benefit from this type of treatment.

  1. Clinical and Economic Implications of AF Related Stroke.

    PubMed

    Ali, Ali N; Abdelhafiz, Ahmed

    2016-01-01

    A major cause of morbidity and mortality among patients with atrial fibrillation (AF) relates to the increased risk of stroke. The burden of illness that AF imparts on stroke is likely to increase with our aging populations and increasingly sophisticated cardiac monitoring techniques. Understanding the clinical and economic differences between AF related ischaemic stroke and non-AF related stroke is important if we are to improve future cost effectiveness analyses of potential preventative treatments, but also to help educate clinical and policy decision makers on use or availability of treatments to prevent AF related stroke. In this article we review the existing evidence that highlights differences in the clinical characteristics and outcomes between AF and non-AF stroke, as well as differences in their economic impact and discuss ways to improve future economic analyses.

  2. GENERAL VIEW SHOWING VENTILATOR NUMBER NINE. THIS VENTILATOR IS SLIGHTLY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW SHOWING VENTILATOR NUMBER NINE. THIS VENTILATOR IS SLIGHTLY MORE ORNATE THAN WAS GENERALLY USED BECAUSE OF ITS LOCATION - Old Croton Aqueduct, Ventilator Number 9, Spring & Everett Streets, Ossining, Westchester County, NY

  3. 1. GENERAL VIEW SHOWING VENTILATOR NO. 9. THIS VENTILATOR IS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. GENERAL VIEW SHOWING VENTILATOR NO. 9. THIS VENTILATOR IS SLIGHTLY MORE ORNATE THAN WAS GENERALLY USED BECAUSE OF ITS LOCATION. - Old Croton Aqueduct, Ventilator Number 9, Spring & Everett Streets, Ossining, Westchester County, NY

  4. Aerosol delivery with two ventilation modes during mechanical ventilation: a randomized study.

    PubMed

    Dugernier, Jonathan; Reychler, Gregory; Wittebole, Xavier; Roeseler, Jean; Depoortere, Virginie; Sottiaux, Thierry; Michotte, Jean-Bernard; Vanbever, Rita; Dugernier, Thierry; Goffette, Pierre; Docquier, Marie-Agnes; Raftopoulos, Christian; Hantson, Philippe; Jamar, François; Laterre, Pierre-François

    2016-12-01

    Volume-controlled ventilation has been suggested to optimize lung deposition during nebulization although promoting spontaneous ventilation is targeted to avoid ventilator-induced diaphragmatic dysfunction. Comparing topographic aerosol lung deposition during volume-controlled ventilation and spontaneous ventilation in pressure support has never been performed. The aim of this study was to compare lung deposition of a radiolabeled aerosol generated with a vibrating-mesh nebulizer during invasive mechanical ventilation, with two modes: pressure support ventilation and volume-controlled ventilation. Seventeen postoperative neurosurgery patients without pulmonary disease were randomly ventilated in pressure support or volume-controlled ventilation. Diethylenetriaminepentaacetic acid labeled with technetium-99m (2 mCi/3 mL) was administrated using a vibrating-mesh nebulizer (Aerogen Solo(®), provided by Aerogen Ltd, Galway, Ireland) connected to the endotracheal tube. Pulmonary and extrapulmonary particles deposition was analyzed using planar scintigraphy. Lung deposition was 10.5 ± 3.0 and 15.1 ± 5.0 % of the nominal dose during pressure support and volume-controlled ventilation, respectively (p < 0.05). Higher endotracheal tube and tracheal deposition was observed during pressure support ventilation (27.4 ± 6.6 vs. 20.7 ± 6.0 %, p < 0.05). A similar penetration index was observed for the right (p = 0.210) and the left lung (p = 0.211) with both ventilation modes. A high intersubject variability of lung deposition was observed with both modes regarding lung doses, aerosol penetration and distribution between the right and the left lung. In the specific conditions of the study, volume-controlled ventilation was associated with higher lung deposition of nebulized particles as compared to pressure support ventilation. The clinical benefit of this effect warrants further studies. Clinical trial registration NCT01879488.

  5. Bone marrow mesenchymal stem cells from infants with MLL-AF4+ acute leukemia harbor and express the MLL-AF4 fusion gene

    PubMed Central

    Catalina, Purificación; Rodríguez, René; Melen, Gustavo J.; Bueno, Clara; Arriero, Mar; García-Sánchez, Félix; Lassaletta, Alvaro; García-Sanz, Ramón

    2009-01-01

    MLL-AF4 fusion is a hallmark genetic abnormality in infant B-acute lymphoblastic leukemia (B-ALL) known to arise in utero. The cellular origin of leukemic fusion genes during human development is difficult to ascertain. The bone marrow (BM) microenvironment plays an important role in the pathogenesis of several hematological malignances. BM mesenchymal stem cells (BM-MSC) from 38 children diagnosed with cytogenetically different acute leukemias were screened for leukemic fusion genes. Fusion genes were absent in BM-MSCs of childhood leukemias carrying TEL-AML1, BCR-ABL, AML1-ETO, MLL-AF9, MLL-AF10, MLL-ENL or hyperdiploidy. However, MLL-AF4 was detected and expressed in BM-MSCs from all cases of MLL-AF4+ B-ALL. Unlike leukemic blasts, MLL-AF4+ BM-MSCs did not display monoclonal Ig gene rearrangements. Endogenous or ectopic expression of MLL-AF4 exerted no effect on MSC culture homeostasis. These findings suggest that MSCs may be in part tumor-related, highlighting an unrecognized role of the BM milieu on the pathogenesis of MLL-AF4+ B-ALL. MLL-AF4 itself is not sufficient for MSC transformation and the expression of MLL-AF4 in MSCs is compatible with a mesenchymal phenotype, suggesting a differential impact in the hematopoietic system and mesenchyme. The absence of monoclonal rearrangements in MLL-AF4+ BM-MSCs precludes the possibility of cellular plasticity or de-differentiation of B-ALL blasts and suggests that MLL-AF4 might arise in a population of prehematopoietic precursors. PMID:19995953

  6. [Pressure support ventilation and proportional assist ventilation during weaning from mechanical ventilation].

    PubMed

    Aguirre-Bermeo, H; Bottiroli, M; Italiano, S; Roche-Campo, F; Santos, J A; Alonso, M; Mancebo, J

    2014-01-01

    To compare tolerance, duration of mechanical ventilation (MV) and clinical outcomes during weaning from MV in patients subjected to either pressure support ventilation (PSV) or proportional assist ventilation (PAV). A prospective, observational study was carried out. Intensive Care Unit. A total of 40 consecutive subjects were allocated to either the PSV or the PAV group until each group contained 20 patients. Patients were included in the study when they met the criteria to begin weaning and the attending physician decided to initiate the weaning process. The physician selected the modality and set the ventilatory parameters. None. Demographic data, respiratory mechanics, ventilatory parameters, duration of MV, and clinical outcomes (reintubation, tracheostomy, mortality). Baseline characteristics were similar in both groups. No significant differences were observed between the PSV and PAV groups in terms of the total duration of MV (10 [5-18] vs. 9 [7-19] days; P=.85), reintubation (5 [31%] vs. 3 [19%]; P=.69), or mortality (4 [20%] vs. 5 [25%] deaths; P=1). Eight patients (40%) in the PSV group and 6 patients (30%) in the PAV group (P=.74) required a return to volume assist-control ventilation due to clinical deterioration. Tolerance, duration of MV and clinical outcomes during weaning from mechanical ventilation were similar in PSV and PAV. Copyright © 2013 Elsevier España, S.L. and SEMICYUC. All rights reserved.

  7. Ventilation.

    PubMed

    Turner, W A; Bearg, D W; Brennan, T

    1995-01-01

    This chapter begins with an overview of the history of ventilation guidelines, which has led to the guidelines that are in effect today. Of particular interest is the most recent return in the past 5 years to ventilation rates that more closely reflect a mean or average of the range of guidelines that have existed over the past century. OSHA's and the EPA's recognition of the need to operate ventilation systems in buildings in an accountable manner is also of note. Of even more interest is the resurgence of the concept of minimum mixing and once-through ventilation air that has been pursued in parts of Northern Europe for the past 10 years, and in a school that is being designed with this concept in New Hampshire. In addition, the design concept of equipping office buildings with low pressure drop high efficiency particle filtration to remove fine particles from all of the air that is supplied to the occupants is being used increasingly in the U.S. This chapter also presents an overview of the various types of ventilation systems found in homes and commercial office buildings and the common indoor air quality problems that may be associated with them. It also offers an overview of common HVAC evaluation techniques that can be used to determine if a ventilation system is performing in a manner that makes sense for the use of the space and the needs of the occupants. Are the occupants receiving a reasonable supply of outdoor air? Is the air that they receive of reasonable quality? Are obvious pollutants being exhausted? Ventilation systems have become extremely complex and more difficult to run and maintain over the past 40 years. This trend will continue to drive the need for professionally maintained HVAC equipment that is serviced and run by individuals who are accountable for the quality of the air that the system delivers.

  8. STBC AF relay for unmanned aircraft system

    NASA Astrophysics Data System (ADS)

    Adachi, Fumiyuki; Miyazaki, Hiroyuki; Endo, Chikara

    2015-01-01

    If a large scale disaster similar to the Great East Japan Earthquake 2011 happens, some areas may be isolated from the communications network. Recently, unmanned aircraft system (UAS) based wireless relay communication has been attracting much attention since it is able to quickly re-establish the connection between isolated areas and the network. However, the channel between ground station (GS) and unmanned aircraft (UA) is unreliable due to UA's swing motion and as consequence, the relay communication quality degrades. In this paper, we introduce space-time block coded (STBC) amplify-and-forward (AF) relay for UAS based wireless relay communication to improve relay communication quality. A group of UAs forms single frequency network (SFN) to perform STBC-AF cooperative relay. In STBC-AF relay, only conjugate operation, block exchange and amplifying are required at UAs. Therefore, STBC-AF relay improves the relay communication quality while alleviating the complexity problem at UAs. It is shown by computer simulation that STBC-AF relay can achieve better throughput performance than conventional AF relay.

  9. AF Sites

    Science.gov Websites

    Speeches Archive Former AF Top 3 Viewpoints and Speeches Air Force Warrior Games 2017 Events 2018 Air Force Strategic Documents Desert Storm 25th Anniversary Observances DoD Warrior Games Portraits in Courage

  10. Nasal mask ventilation is better than face mask ventilation in edentulous patients.

    PubMed

    Kapoor, Mukul Chandra; Rana, Sandeep; Singh, Arvind Kumar; Vishal, Vindhya; Sikdar, Indranil

    2016-01-01

    Face mask ventilation of the edentulous patient is often difficult as ineffective seating of the standard mask to the face prevents attainment of an adequate air seal. The efficacy of nasal ventilation in edentulous patients has been cited in case reports but has never been investigated. Consecutive edentulous adult patients scheduled for surgery under general anesthesia with endotracheal intubation, during a 17-month period, were prospectively evaluated. After induction of anesthesia and administration of neuromuscular blocker, lungs were ventilated with a standard anatomical face mask of appropriate size, using a volume controlled anesthesia ventilator with tidal volume set at 10 ml/kg. In case of inadequate ventilation, the mask position was adjusted to achieve best-fit. Inspired and expired tidal volumes were measured. Thereafter, the face mask was replaced by a nasal mask and after achieving best-fit, the inspired and expired tidal volumes were recorded. The difference in expired tidal volumes and airway pressures at best-fit with the use of the two masks and number of patients with inadequate ventilation with use of the masks were statistically analyzed. A total of 79 edentulous patients were recruited for the study. The difference in expiratory tidal volumes with the use of the two masks at best-fit was statistically significant (P = 0.0017). Despite the best-fit mask placement, adequacy of ventilation could not be achieved in 24.1% patients during face mask ventilation, and 12.7% patients during nasal mask ventilation and the difference was statistically significant. Nasal mask ventilation is more efficient than standard face mask ventilation in edentulous patients.

  11. History of Mechanical Ventilation. From Vesalius to Ventilator-induced Lung Injury.

    PubMed

    Slutsky, Arthur S

    2015-05-15

    Mechanical ventilation is a life-saving therapy that catalyzed the development of modern intensive care units. The origins of modern mechanical ventilation can be traced back about five centuries to the seminal work of Andreas Vesalius. This article is a short history of mechanical ventilation, tracing its origins over the centuries to the present day. One of the great advances in ventilatory support over the past few decades has been the development of lung-protective ventilatory strategies, based on our understanding of the iatrogenic consequences of mechanical ventilation such as ventilator-induced lung injury. These strategies have markedly improved clinical outcomes in patients with respiratory failure.

  12. Nasal mask ventilation is better than face mask ventilation in edentulous patients

    PubMed Central

    Kapoor, Mukul Chandra; Rana, Sandeep; Singh, Arvind Kumar; Vishal, Vindhya; Sikdar, Indranil

    2016-01-01

    Background and Aims: Face mask ventilation of the edentulous patient is often difficult as ineffective seating of the standard mask to the face prevents attainment of an adequate air seal. The efficacy of nasal ventilation in edentulous patients has been cited in case reports but has never been investigated. Material and Methods: Consecutive edentulous adult patients scheduled for surgery under general anesthesia with endotracheal intubation, during a 17-month period, were prospectively evaluated. After induction of anesthesia and administration of neuromuscular blocker, lungs were ventilated with a standard anatomical face mask of appropriate size, using a volume controlled anesthesia ventilator with tidal volume set at 10 ml/kg. In case of inadequate ventilation, the mask position was adjusted to achieve best-fit. Inspired and expired tidal volumes were measured. Thereafter, the face mask was replaced by a nasal mask and after achieving best-fit, the inspired and expired tidal volumes were recorded. The difference in expired tidal volumes and airway pressures at best-fit with the use of the two masks and number of patients with inadequate ventilation with use of the masks were statistically analyzed. Results: A total of 79 edentulous patients were recruited for the study. The difference in expiratory tidal volumes with the use of the two masks at best-fit was statistically significant (P = 0.0017). Despite the best-fit mask placement, adequacy of ventilation could not be achieved in 24.1% patients during face mask ventilation, and 12.7% patients during nasal mask ventilation and the difference was statistically significant. Conclusion: Nasal mask ventilation is more efficient than standard face mask ventilation in edentulous patients. PMID:27625477

  13. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-1 Power ventilation systems except machinery space ventilation systems. Each power ventilation system must... 46 Shipping 4 2010-10-01 2010-10-01 false Power ventilation systems except machinery space...

  14. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-1 Power ventilation systems except machinery space ventilation systems. Each power ventilation system must... 46 Shipping 4 2011-10-01 2011-10-01 false Power ventilation systems except machinery space...

  15. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-1 Power ventilation systems except machinery space ventilation systems. Each power ventilation system must... 46 Shipping 4 2014-10-01 2014-10-01 false Power ventilation systems except machinery space...

  16. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-1 Power ventilation systems except machinery space ventilation systems. Each power ventilation system must... 46 Shipping 4 2012-10-01 2012-10-01 false Power ventilation systems except machinery space...

  17. 46 CFR 111.103-1 - Power ventilation systems except machinery space ventilation systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-1 Power ventilation systems except machinery space ventilation systems. Each power ventilation system must... 46 Shipping 4 2013-10-01 2013-10-01 false Power ventilation systems except machinery space...

  18. Potential risk for bacterial contamination in conventional reused ventilator systems and disposable closed ventilator-suction systems.

    PubMed

    Li, Ya-Chi; Lin, Hui-Ling; Liao, Fang-Chun; Wang, Sing-Siang; Chang, Hsiu-Chu; Hsu, Hung-Fu; Chen, Sue-Hsien; Wan, Gwo-Hwa

    2018-01-01

    Few studies have investigated the difference in bacterial contamination between conventional reused ventilator systems and disposable closed ventilator-suction systems. The aim of this study was to investigate the bacterial contamination rates of the reused and disposable ventilator systems, and the association between system disconnection and bacterial contamination of ventilator systems. The enrolled intubated and mechanically ventilated patients used a conventional reused ventilator system and a disposable closed ventilator-suction system, respectively, for a week; specimens were then collected from the ventilator circuit systems to evaluate human and environmental bacterial contamination. The sputum specimens from patients were also analyzed in this study. The detection rate of bacteria in the conventional reused ventilator system was substantially higher than that in the disposable ventilator system. The inspiratory and expiratory limbs of the disposable closed ventilator-suction system had higher bacterial concentrations than the conventional reused ventilator system. The bacterial concentration in the heated humidifier of the reused ventilator system was significantly higher than that in the disposable ventilator system. Positive associations existed among the bacterial concentrations at different locations in the reused and disposable ventilator systems, respectively. The predominant bacteria identified in the reused and disposable ventilator systems included Acinetobacter spp., Bacillus cereus, Elizabethkingia spp., Pseudomonas spp., and Stenotrophomonas (Xan) maltophilia. Both the reused and disposable ventilator systems had high bacterial contamination rates after one week of use. Disconnection of the ventilator systems should be avoided during system operation to decrease the risks of environmental pollution and human exposure, especially for the disposable ventilator system. ClinicalTrials.gov PRS / NCT03359148.

  19. Accuracy of tidal volume delivered by home mechanical ventilation during mouthpiece ventilation

    PubMed Central

    Prigent, Helene; Falaize, Line; Leroux, Karl; Santos, Dante; Vaugier, Isabelle; Orlikowski, David; Lofaso, Frederic

    2016-01-01

    The aim of our study was to evaluate efficacy and reliability of currently available ventilators for mouthpiece ventilation (MPV). Five life-support home ventilators were assessed in a bench test using different settings simulating the specificities of MPV, such as intermittent circuit disconnection and presence of continuous leaks. The intermittent disconnection of the circuit caused relevant swings in the delivered tidal volume (VT), showing a VT overshoot during the disconnection periods and a VT decrease when the interface was reconnected to the test lung. The five ventilators showed substantial differences in the number of respiratory cycles necessary to reach a stable VT in the volume-controlled setting, ranging from 1.3 ± 0.6 to 7.3 ± 1.2 cycles. These differences were less accentuated in the volume-assisted setting (MPV-dedicated mode, when available). Our data show large differences in the capacity of the different ventilators to deal with the rapidly changing respiratory load features that characterize MPV, which can be further accentuated according to the used ventilator setting. The dedicated MPV modes allow improvement in the performance of ventilators only in some defined situations. This has practical consequences for the choice of the ventilator to be used for MPV in a specific patient. PMID:27146811

  20. Potential risk for bacterial contamination in conventional reused ventilator systems and disposable closed ventilator-suction systems

    PubMed Central

    Li, Ya-Chi; Lin, Hui-Ling; Liao, Fang-Chun; Wang, Sing-Siang; Chang, Hsiu-Chu; Hsu, Hung-Fu; Chen, Sue-Hsien

    2018-01-01

    Background Few studies have investigated the difference in bacterial contamination between conventional reused ventilator systems and disposable closed ventilator-suction systems. The aim of this study was to investigate the bacterial contamination rates of the reused and disposable ventilator systems, and the association between system disconnection and bacterial contamination of ventilator systems. Methods The enrolled intubated and mechanically ventilated patients used a conventional reused ventilator system and a disposable closed ventilator-suction system, respectively, for a week; specimens were then collected from the ventilator circuit systems to evaluate human and environmental bacterial contamination. The sputum specimens from patients were also analyzed in this study. Results The detection rate of bacteria in the conventional reused ventilator system was substantially higher than that in the disposable ventilator system. The inspiratory and expiratory limbs of the disposable closed ventilator-suction system had higher bacterial concentrations than the conventional reused ventilator system. The bacterial concentration in the heated humidifier of the reused ventilator system was significantly higher than that in the disposable ventilator system. Positive associations existed among the bacterial concentrations at different locations in the reused and disposable ventilator systems, respectively. The predominant bacteria identified in the reused and disposable ventilator systems included Acinetobacter spp., Bacillus cereus, Elizabethkingia spp., Pseudomonas spp., and Stenotrophomonas (Xan) maltophilia. Conclusions Both the reused and disposable ventilator systems had high bacterial contamination rates after one week of use. Disconnection of the ventilator systems should be avoided during system operation to decrease the risks of environmental pollution and human exposure, especially for the disposable ventilator system. Trial registration Clinical

  1. Analysis on ventilation pressure of fire area in longitudinal ventilation of underground tunnel

    NASA Astrophysics Data System (ADS)

    Li, Jiaxin; Li, Yanfeng; Feng, Xiao; Li, Junmei

    2018-03-01

    In order to solve the problem of ventilation pressure loss in the fire area under the fire condition, the wind pressure loss model of the fire area is established based on the thermodynamic equilibrium relation. The semi-empirical calculation formula is obtained by using the model experiment and CFD simulation. The validity of the formula is verified. The results show that the ventilation pressure loss in the fire zone is proportional to the convective heat release rate at the critical velocity, which is inversely proportional to the upstream ventilation velocity and the tunnel cross-sectional area. The proposed formula is consistent with the law of the tunnel fire test fitting formula that results are close, in contrast, the advantage lies in a clear theoretical basis and ventilation velocity values. The resistance of road tunnel ventilation system is calculated accurately and reliably, and then an effective emergency ventilation operation program is developed. It is necessary to consider the fire zone ventilation pressure loss. The proposed ventilation pressure loss formula can be used for design calculation after thorough verification.

  2. Oral mask ventilation is more effective than face mask ventilation after nasal surgery.

    PubMed

    Yazicioğlu, Dilek; Baran, Ilkay; Uzumcugil, Filiz; Ozturk, Ibrahim; Utebey, Gulten; Sayın, M Murat

    2016-06-01

    To evaluate and compare the face mask (FM) and oral mask (OM) ventilation techniques during anesthesia emergence regarding tidal volume, leak volume, and difficult mask ventilation (DMV) incidence. Prospective, randomized, crossover study. Operating room, training and research hospital. American Society of Anesthesiologists physical status I and II adult patients scheduled for nasal surgery. Patients in group FM-OM received FM ventilation first, followed by OM ventilation, and patients in group OM-FM received OM ventilation first, followed by FM ventilation, with spontaneous ventilation after deep extubation. The FM ventilation was applied with the 1-handed EC-clamp technique. The OM was placed only over the mouth, and the 1-handed EC-clamp technique was used again. A child's size FM was used for the OM ventilation technique, the mask was rotated, and the inferior part of the mask was placed toward the nose. The leak volume (MVleak), mean airway pressure (Pmean), and expired tidal volume (TVe) were assessed with each mask technique for 3 consecutive breaths. A mask ventilation grade ≥3 was considered DMV. DMV occurred more frequently during FM ventilation (75% with FM vs 8% with OM). In the FM-first sequence, the mean TVe was 249±61mL with the FM and 455±35mL with the OM (P=.0001), whereas in the OM-first sequence, it was 276±81mL with the FM and 409±37mL with the OM (P=.0001). Regardless of the order used, the OM technique significantly decreased the MVleak and increased the TVe when compared to the FM technique. During anesthesia emergence after nasal surgery the OM may offer an effective ventilation method as it decreases the incidence of DMV and the gas leak around the mask and provides higher tidal volume delivery compared with FM ventilation. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Pediatric Ventilator-Associated Infections: The Ventilator-Associated INfection Study.

    PubMed

    Willson, Douglas F; Hoot, Michelle; Khemani, Robinder; Carrol, Christopher; Kirby, Aileen; Schwarz, Adam; Gedeit, Rainer; Nett, Sholeen T; Erickson, Simon; Flori, Heidi; Hays, Spencer; Hall, Mark

    2017-01-01

    Suspected ventilator-associated infection is the most common reason for antibiotics in the PICU. We sought to characterize the clinical variables associated with continuing antibiotics after initial evaluation for suspected ventilator-associated infection and to determine whether clinical variables or antibiotic treatment influenced outcomes. Prospective, observational cohort study conducted in 47 PICUs in the United States, Canada, and Australia. Two hundred twenty-nine pediatric patients ventilated more than 48 hours undergoing respiratory secretion cultures were enrolled as "suspected ventilator-associated infection" in a prospective cohort study, those receiving antibiotics of less than or equal to 3 days were categorized as "evaluation only," and greater than 3 days as "treated." Demographics, diagnoses, comorbidities, culture results, and clinical data were compared between evaluation only and treated subjects and between subjects with positive versus negative cultures. PICUs in 47 hospitals in the United States, Canada, and Australia. All patients undergoing respiratory secretion cultures during the 6 study periods. None. Treated subjects differed from evaluation-only subjects only in frequency of positive cultures (79% vs 36%; p < 0.0001). Subjects with positive cultures were more likely to have chronic lung disease, tracheostomy, and shorter PICU stay, but there were no differences in ventilator days or mortality. Outcomes were similar in subjects with positive or negative cultures irrespective of antibiotic treatment. Immunocompromise and higher Pediatric Logistic Organ Dysfunction scores were the only variables associated with mortality in the overall population, but treated subjects with endotracheal tubes had significantly lower mortality. Positive respiratory cultures were the primary determinant of continued antibiotic treatment in children with suspected ventilator-associated infection. Positive cultures were not associated with worse outcomes

  4. Transient spontaneous remission in congenital MLL-AF10 rearranged acute myeloid leukemia presenting with cardiorespiratory failure and meconium ileus.

    PubMed

    Gyárfás, Tobias; Wintgens, Juergen; Biskup, Wolfgang; Oschlies, Ilske; Klapper, Wolfram; Siebert, Reiner; Bens, Susanne; Haferlach, Claudia; Meisel, Roland; Kuhlen, Michaela; Borkhardt, Arndt

    2016-12-01

    Neonatal leukemia is a rare disease with an estimated prevalence of about one to five in a million neonates. The majority being acute myeloid leukemia (AML), neonatal leukemia can present with a variety of symptoms including hyperleucocytosis, cytopenia, hepatosplenomegaly, and skin infiltrates. Chromosomal rearrangements including mixed lineage leukemia (MLL) translocations are common in neonatal AML. A female neonate born at 34 weeks gestation presented with cardiorespiratory failure, hepatosplenomegaly, pancytopenia, and coagulopathy. She required intensive care treatment including mechanical ventilation, high-dose catecholamine therapy, and multiple transfusions. Small intestinal biopsy obtained during laparotomy for meconium ileus revealed an infiltrate by an undifferentiated monoblastic, MLL-rearranged leukemia. No other manifestations of leukemia could be detected. After spontaneous clinical remission, lasting 5 months without any specific treatment, the patient presented with leukemia cutis and full-blown monoblastic leukemia. MLL-AF10-rearranged AML could be re-diagnosed and successfully treated with chemotherapy and hematopoietic stem cell transplantation. Our patient exhibited a unique manifestation of neonatal MLL-AF10 rearranged AML with cardiorespiratory failure and intestinal infiltration. It highlights the importance of leukemia in the differential diagnosis of neonatal distress, congenital hematological abnormalities, and skin lesions.

  5. Clinical challenges in mechanical ventilation.

    PubMed

    Goligher, Ewan C; Ferguson, Niall D; Brochard, Laurent J

    2016-04-30

    Mechanical ventilation supports gas exchange and alleviates the work of breathing when the respiratory muscles are overwhelmed by an acute pulmonary or systemic insult. Although mechanical ventilation is not generally considered a treatment for acute respiratory failure per se, ventilator management warrants close attention because inappropriate ventilation can result in injury to the lungs or respiratory muscles and worsen morbidity and mortality. Key clinical challenges include averting intubation in patients with respiratory failure with non-invasive techniques for respiratory support; delivering lung-protective ventilation to prevent ventilator-induced lung injury; maintaining adequate gas exchange in severely hypoxaemic patients; avoiding the development of ventilator-induced diaphragm dysfunction; and diagnosing and treating the many pathophysiological mechanisms that impair liberation from mechanical ventilation. Personalisation of mechanical ventilation based on individual physiological characteristics and responses to therapy can further improve outcomes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. AF-Shell 1.0 User Guide

    NASA Technical Reports Server (NTRS)

    McElroy, Mark W.

    2017-01-01

    This document serves as a user guide for the AF-Shell 1.0 software, an efficient tool for progressive damage simulation in composite laminates. This guide contains minimal technical material and is meant solely as a guide for a new user to apply AF-Shell 1.0 to laminate damage simulation problems.

  7. Negative pressure ventilation and positive pressure ventilation promote comparable levels of ventilator-induced diaphragmatic dysfunction in rats.

    PubMed

    Bruells, Christian S; Smuder, Ashley J; Reiss, Lucy K; Hudson, Matthew B; Nelson, William Bradley; Wiggs, Michael P; Sollanek, Kurt J; Rossaint, Rolf; Uhlig, Stefan; Powers, Scott K

    2013-09-01

    Mechanical ventilation is a life-saving intervention for patients with respiratory failure. Unfortunately, a major complication associated with prolonged mechanical ventilation is ventilator-induced diaphragmatic atrophy and contractile dysfunction, termed ventilator-induced diaphragmatic dysfunction (VIDD). Emerging evidence suggests that positive pressure ventilation (PPV) promotes lung damage (ventilator-induced lung injury [VILI]), resulting in the release of signaling molecules that foster atrophic signaling in the diaphragm and the resultant VIDD. Although a recent report suggests that negative pressure ventilation (NPV) results in less VILI than PPV, it is unknown whether NPV can protect against VIDD. Therefore, the authors tested the hypothesis that compared with PPV, NPV will result in a lower level of VIDD. Adult rats were randomly assigned to one of three experimental groups (n = 8 each): (1) acutely anesthetized control (CON), (2) 12 h of PPV, and (3) 12 h of NPV. Dependent measures included indices of VILI, diaphragmatic muscle fiber cross-sectional area, diaphragm contractile properties, and the activity of key proteases in the diaphragm. Our results reveal that no differences existed in the degree of VILI between PPV and NPV animals as evidenced by VILI histological scores (CON = 0.082 ± 0.001; PPV = 0.22 ± 0.04; NPV = 0.25 ± 0.02; mean ± SEM). Both PPV and NPV resulted in VIDD. Importantly, no differences existed between PPV and NPV animals in diaphragmatic fiber cross-sectional area, contractile properties, and the activation of proteases. These results demonstrate that NPV and PPV result in similar levels of VILI and that NPV and PPV promote comparable levels of VIDD in rats.

  8. Wild-Type U2AF1 Antagonizes the Splicing Program Characteristic of U2AF1-Mutant Tumors and Is Required for Cell Survival

    PubMed Central

    Fei, Dennis Liang; Motowski, Hayley; Chatrikhi, Rakesh; Gao, Shaojian; Kielkopf, Clara L.; Varmus, Harold

    2016-01-01

    We have asked how the common S34F mutation in the splicing factor U2AF1 regulates alternative splicing in lung cancer, and why wild-type U2AF1 is retained in cancers with this mutation. A human lung epithelial cell line was genetically modified so that U2AF1S34F is expressed from one of the two endogenous U2AF1 loci. By altering levels of mutant or wild-type U2AF1 in this cell line and by analyzing published data on human lung adenocarcinomas, we show that S34F-associated changes in alternative splicing are proportional to the ratio of S34F:wild-type gene products and not to absolute levels of either the mutant or wild-type factor. Preferential recognition of specific 3′ splice sites in S34F-expressing cells is largely explained by differential in vitro RNA-binding affinities of mutant versus wild-type U2AF1 for those same 3′ splice sites. Finally, we show that lung adenocarcinoma cell lines bearing U2AF1 mutations do not require the mutant protein for growth in vitro or in vivo. In contrast, wild-type U2AF1 is required for survival, regardless of whether cells carry the U2AF1S34F allele. Our results provide mechanistic explanations of the magnitude of splicing changes observed in U2AF1-mutant cells and why tumors harboring U2AF1 mutations always retain an expressed copy of the wild-type allele. PMID:27776121

  9. Gas exchange and intrapulmonary distribution of ventilation during continuous-flow ventilation

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

    Vettermann, J.; Brusasco, V.; Rehder, K.

    1988-05-01

    In 12 anesthetized paralyzed dogs, pulmonary gas exchange and intrapulmonary inspired gas distribution were compared between continuous-flow ventilation (CFV) and conventional mechanical ventilation (CMV). Nine dogs were studied while they were lying supine, and three dogs were studied while they were lying prone. A single-lumen catheter for tracheal insufflation and a double-lumen catheter for bilateral endobronchial insufflation (inspired O2 fraction = 0.4; inspired minute ventilation = 1.7 +/- 0.3 (SD) 1.kg-1.min-1) were evaluated. Intrapulmonary gas distribution was assessed from regional 133Xe clearances. In dogs lying supine, CO2 elimination was more efficient with endobronchial insufflation than with tracheal insufflation, but themore » alveolar-arterial O2 partial pressure difference was larger during CFV than during CMV, regardless of the type of insufflation. By contrast, endobronchial insufflation maintained both arterial PCO2 and alveolar-arterial O2 partial pressure difference at significantly lower levels in dogs lying prone than in dogs lying supine. In dogs lying supine, the dependent lung was preferentially ventilated during CMV but not during CFV. In dogs lying prone, gas distribution was uniform with both modes of ventilation. The alveolar-arterial O2 partial pressure difference during CFV in dogs lying supine was negatively correlated with the reduced ventilation of the dependent lung, which suggests that increased ventilation-perfusion mismatching was responsible for the increase in alveolar-arterial O2 partial pressure difference. The more efficient oxygenation during CFV in dogs lying prone suggests a more efficient matching of ventilation to perfusion, presumably because the distribution of blood flow is also nearly uniform.« less

  10. AF-GEOSpace Version 2.1 Release

    NASA Astrophysics Data System (ADS)

    Hilmer, R. V.; Ginet, G. P.; Hall, T.; Holeman, E.; Madden, D.; Perry, K. L.; Tautz, M.; Roth, C.

    2006-05-01

    AF-GEOSpace Version 2.1 is a graphics-intensive software program with space environment models and applications developed recently by the Space Weather Center of Excellence at AFRL. A review of new and planned AF-GEOSpace capabilities will be given. The software addresses a wide range of physical domains and addresses such topics as solar disturbance propagation, geomagnetic field and radiation belt configurations, auroral particle precipitation, and ionospheric scintillation. Building on the success of previous releases, AF-GEOSpace has become a platform for the rapid prototyping of automated operational and simulation space weather visualization products and helps with a variety of tasks, including: orbit specification for radiation hazard avoidance; satellite design assessment and post-event anomaly analysis; solar disturbance effects forecasting; determination of link outage regions for active ionospheric conditions; satellite magnetic conjugate studies, scientific model validation and comparison, physics research, and education. Previously, Version 2.0 provided a simplified graphical user interface, improved science and application modules, significantly enhanced graphical performance, common input data archive sets, and 1-D, 2-D, and 3- D visualization tools for all models. Dynamic capabilities permit multiple environments to be generated at user- specified time intervals while animation tools enable the display of satellite orbits and environment data together as a function of time. Building on the Version 2.0 software architecture, AF-GEOSpace Version 2.1 includes a host of new modules providing, for example, plasma sheet charged particle fluxes, neutral atmosphere densities, 3-D cosmic ray cutoff maps, low-altitude trapped proton belt flux specification, DMSP particle data displays, satellite magnetic field footprint mapping determination, and meteor sky maps and shower/storm fluxes with spacecraft impact probabilities. AF-GEOSpace Version 2.1 was

  11. The growing role of noninvasive ventilation in patients requiring prolonged mechanical ventilation.

    PubMed

    Hess, Dean R

    2012-06-01

    For many patients with chronic respiratory failure requiring ventilator support, noninvasive ventilation (NIV) is preferable to invasive support by tracheostomy. Currently available evidence does not support the use of nocturnal NIV in unselected patients with stable COPD. Several European studies have reported benefit for high intensity NIV, in which setting of inspiratory pressure and respiratory rate are selected to achieve normocapnia. There have also been studies reporting benefit for the use of NIV as an adjunct to exercise training. NIV may be useful as an adjunct to airway clearance techniques in patients with cystic fibrosis. Accumulating evidence supports the use of NIV in patients with obesity hypoventilation syndrome. There is considerable observational evidence supporting the use of NIV in patients with chronic respiratory failure related to neuromuscular disease, and one randomized controlled trial reported that the use of NIV was life-prolonging in patients with amyotrophic lateral sclerosis. A variety of interfaces can be used to provide NIV in patients with stable chronic respiratory failure. The mouthpiece is an interface that is unique in this patient population, and has been used with success in patients with neuromuscular disease. Bi-level pressure ventilators are commonly used for NIV, although there are now a new generation of intermediate ventilators that are portable, have a long battery life, and can be used for NIV and invasive applications. Pressure support ventilation, pressure controlled ventilation, and volume controlled ventilation have been used successfully for chronic applications of NIV. New modes have recently become available, but their benefits await evidence to support their widespread use. The success of NIV in a given patient population depends on selection of an appropriate patient, selection of an appropriate interface, selection of an appropriate ventilator and ventilator settings, the skills of the clinician, the

  12. VENTILATION TECHNOLOGY SYSTEMS ANALYSIS

    EPA Science Inventory

    The report gives results of a project to develop a systems analysis of ventilation technology and provide a state-of-the-art assessment of ventilation and indoor air quality (IAQ) research needs. (NOTE: Ventilation technology is defined as the hardware necessary to bring outdoor ...

  13. Using a Ventilation Controller to Optimize Residential Passive Ventilation For Energy and Indoor Air Quality

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

    Turner, William; Walker, Iain

    One way to reduce the energy impact of providing residential ventilation is to use passive and hybrid systems. However, these passive and hybrid (sometimes called mixed-mode) systems must still meet chronic and acute health standards for ventilation. This study uses a computer simulation approach to examine the energy and indoor air quality (IAQ) implications of passive and hybrid ventilation systems, in 16 California climate zones. Both uncontrolled and flow controlled passive stacks are assessed. A new hybrid ventilation system is outlined that uses an intelligent ventilation controller to minimise energy use, while ensuring chronic and acute IAQ standards are met.more » ASHRAE Standard 62.2-2010 – the United States standard for residential ventilation - is used as the chronic standard, and exposure limits for PM 2.5, formaldehyde and NO 2 are used as the acute standards.The results show that controlled passive ventilation and hybrid ventilation can be used in homes to provide equivalent IAQ to continuous mechanical ventilation, for less use of energy.« less

  14. Identification of U2AF(35)-dependent exons by RNA-Seq reveals a link between 3′ splice-site organization and activity of U2AF-related proteins

    PubMed Central

    Kralovicova, Jana; Knut, Marcin; Cross, Nicholas C. P.; Vorechovsky, Igor

    2015-01-01

    The auxiliary factor of U2 small nuclear RNA (U2AF) is a heterodimer consisting of 65- and 35-kD proteins that bind the polypyrimidine tract (PPT) and AG dinucleotides at the 3′ splice site (3′ss). The gene encoding U2AF35 (U2AF1) is alternatively spliced, giving rise to two isoforms U2AF35a and U2AF35b. Here, we knocked down U2AF35 and each isoform and characterized transcriptomes of HEK293 cells with varying U2AF35/U2AF65 and U2AF35a/b ratios. Depletion of both isoforms preferentially modified alternative RNA processing events without widespread failure to recognize 3′ss or constitutive exons. Over a third of differentially used exons were terminal, resulting largely from the use of known alternative polyadenylation (APA) sites. Intronic APA sites activated in depleted cultures were mostly proximal whereas tandem 3′UTR APA was biased toward distal sites. Exons upregulated in depleted cells were preceded by longer AG exclusion zones and PPTs than downregulated or control exons and were largely activated by PUF60 and repressed by CAPERα. The U2AF(35) repression and activation was associated with a significant interchange in the average probabilities to form single-stranded RNA in the optimal PPT and branch site locations and sequences further upstream. Although most differentially used exons were responsive to both U2AF subunits and their inclusion correlated with U2AF levels, a small number of transcripts exhibited distinct responses to U2AF35a and U2AF35b, supporting the existence of isoform-specific interactions. These results provide new insights into function of U2AF and U2AF35 in alternative RNA processing. PMID:25779042

  15. Characteristics of rain penetration through a gravity ventilator used for natural ventilation.

    PubMed

    Kim, Taehyeung; Lee, Dong Ho; Ahn, Kwangseog; Ha, Hyunchul; Park, Heechang; Piao, Cheng Xu; Li, Xiaoyu; Seo, Jeoungyoon

    2008-01-01

    Gravity ventilators rely simply on air buoyancy to extract air and are widely used to exhaust air contaminants and heat from workplaces using minimal energy. They are designed to maximize the exhaust flow rate, but the rain penetration sometimes causes malfunctioning. In this study, the characteristics of rain penetration through a ventilator were examined as a preliminary study to develop a ventilator with the maximum exhaust capacity while minimizing rain penetration. A model ventilator was built and exposed to artificial rain and wind. The paths, intensities and amounts of penetration through the ventilator were observed and measured in qualitative and quantitative fashions. In the first phase, the pathways and intensities of rain penetration were visually observed. In the second phase, the amounts of rain penetration were quantitatively measured under the different configurations of ventilator components that were installed based on the information obtained in the first-phase experiment. The effects of wind speed, grill direction, rain drainage width, outer wall height, neck height and leaning angle of the outer wall from the vertical position were analyzed. Wind speed significantly affected rain penetration. Under the low crosswind conditions, the rain penetration intensities were under the limit of detection. Under the high crosswind conditions, grill direction and neck height were the most significant factors in reducing rain penetration. The installation of rain drainage was also important in reducing rain penetration. The experimental results suggest that, with proper configurations of its components, a gravity ventilator can be used for natural ventilation without significant rain penetration problems.

  16. Is AF Ablation Cost Effective?

    PubMed Central

    Martin-Doyle, William; Reynolds, Matthew R.

    2010-01-01

    The use of catheter ablation to treat AF is increasing rapidly, but there is presently an incomplete understanding of its cost-effectiveness. AF ablation procedures involve significant up-front expenditures, but multiple randomized trials have demonstrated that ablation is more effective than antiarrhythmic drugs at maintaining sinus rhythm in a second-line and possibly first-line rhythm control setting. Although truly long-term data are limited, ablation, as compared with antiarrrhythmic drugs, also appears associated with improved symptoms and quality of life and a reduction in downstream hospitalization and other health care resource utilization. Several groups have developed cost effectiveness models comparing AF ablation primarily to antiarrhythmic drugs and the model results suggest that ablation likely falls within the range generally accepted as cost-effective in developed nations. This paper will review available information on the cost-effectiveness of catheter ablation for the treatment of atrial fibrillation, and discuss continued areas of uncertainty where further research is required. PMID:20936083

  17. Noninvasive Ventilation in Premature Neonates.

    PubMed

    Flanagan, Keri Ann

    2016-04-01

    The use of noninvasive ventilation is a constantly evolving treatment option for respiratory disease in the premature infant. The goals of these noninvasive ventilation techniques are to improve gas exchange in the premature infant's lungs and to minimize the need for intubation and invasive mechanical ventilation. The goals of this article are to consider various uses of nasal interfaces, discuss skin care and developmental positioning concerns faced by the bedside nurse, and discuss the medical management aimed to reduce morbidity and mortality. This article explores the nursing role, the advances in medical strategies for noninvasive ventilation, and the team approach to noninvasive ventilation use in this population. Search strategy included a literature review on medical databases, such as EBSCOhost, CINAHL, PubMed, and NeoReviews. Innovative products, nursing research on developmental positioning and skin care, and advanced medical management have led to better and safer outcomes for premature infants requiring noninvasive ventilation. The medical focus of avoiding long-term mechanical ventilation would not be possible without the technology to provide noninvasive ventilation to these premature infants and the watchful eye of the nurse in terms of careful positioning, preventing skin breakdown and facial scarring, and a proper seal to maximize ventilation accuracy. This article encourages nursing-based research to quantify some of the knowledge about skin care and positioning as well as research into most appropriate uses for noninvasive ventilation devices.

  18. Comparison of 4-Dimensional Computed Tomography Ventilation With Nuclear Medicine Ventilation-Perfusion Imaging: A Clinical Validation Study

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

    Vinogradskiy, Yevgeniy, E-mail: yevgeniy.vinogradskiy@ucdenver.edu; Koo, Phillip J.; Castillo, Richard

    Purpose: Four-dimensional computed tomography (4DCT) ventilation imaging provides lung function information for lung cancer patients undergoing radiation therapy. Before 4DCT-ventilation can be implemented clinically it needs to be validated against an established imaging modality. The purpose of this work was to compare 4DCT-ventilation to nuclear medicine ventilation, using clinically relevant global metrics and radiologist observations. Methods and Materials: Fifteen lung cancer patients with 16 sets of 4DCT and nuclear medicine ventilation-perfusion (VQ) images were used for the study. The VQ-ventilation images were acquired in planar mode using Tc-99m-labeled diethylenetriamine-pentaacetic acid aerosol inhalation. 4DCT data, spatial registration, and a density-change-based modelmore » were used to compute a 4DCT-based ventilation map for each patient. The percent ventilation was calculated in each lung and each lung third for both the 4DCT and VQ-ventilation scans. A nuclear medicine radiologist assessed the VQ and 4DCT scans for the presence of ventilation defects. The VQ and 4DCT-based images were compared using regional percent ventilation and radiologist clinical observations. Results: Individual patient examples demonstrate good qualitative agreement between the 4DCT and VQ-ventilation scans. The correlation coefficients were 0.68 and 0.45, using the percent ventilation in each individual lung and lung third, respectively. Using radiologist-noted presence of ventilation defects and receiver operating characteristic analysis, the sensitivity, specificity, and accuracy of the 4DCT-ventilation were 90%, 64%, and 81%, respectively. Conclusions: The current work compared 4DCT with VQ-based ventilation using clinically relevant global metrics and radiologist observations. We found good agreement between the radiologist's assessment of the 4DCT and VQ-ventilation images as well as the percent ventilation in each lung. The agreement lessened when the data were

  19. Mechanical ventilator - infants

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/007240.htm Mechanical ventilator - infants To use the sharing features on this page, please enable JavaScript. A mechanical ventilator is a machine that assists with breathing. ...

  20. Liquid ventilation.

    PubMed

    Sarkar, Suman; Paswan, Anil; Prakas, S

    2014-01-01

    Human have lungs to breathe air and they have no gills to breath liquids like fish. When the surface tension at the air-liquid interface of the lung increases as in acute lung injury, scientists started to think about filling the lung with fluid instead of air to reduce the surface tension and facilitate ventilation. Liquid ventilation (LV) is a technique of mechanical ventilation in which the lungs are insufflated with an oxygenated perfluorochemical liquid rather than an oxygen-containing gas mixture. The use of perfluorochemicals, rather than nitrogen as the inert carrier of oxygen and carbon dioxide offers a number of advantages for the treatment of acute lung injury. In addition, there are non-respiratory applications with expanding potential including pulmonary drug delivery and radiographic imaging. It is well-known that respiratory diseases are one of the most common causes of morbidity and mortality in intensive care unit. During the past few years several new modalities of treatment have been introduced. One of them and probably the most fascinating, is of LV. Partial LV, on which much of the existing research has concentrated, requires partial filling of lungs with perfluorocarbons (PFC's) and ventilation with gas tidal volumes using conventional mechanical ventilators. Various physico-chemical properties of PFC's make them the ideal media. It results in a dramatic improvement in lung compliance and oxygenation and decline in mean airway pressure and oxygen requirements. No long-term side-effect reported.

  1. CFD and ventilation research.

    PubMed

    Li, Y; Nielsen, P V

    2011-12-01

    There has been a rapid growth of scientific literature on the application of computational fluid dynamics (CFD) in the research of ventilation and indoor air science. With a 1000-10,000 times increase in computer hardware capability in the past 20 years, CFD has become an integral part of scientific research and engineering development of complex air distribution and ventilation systems in buildings. This review discusses the major and specific challenges of CFD in terms of turbulence modelling, numerical approximation, and boundary conditions relevant to building ventilation. We emphasize the growing need for CFD verification and validation, suggest ongoing needs for analytical and experimental methods to support the numerical solutions, and discuss the growing capacity of CFD in opening up new research areas. We suggest that CFD has not become a replacement for experiment and theoretical analysis in ventilation research, rather it has become an increasingly important partner. We believe that an effective scientific approach for ventilation studies is still to combine experiments, theory, and CFD. We argue that CFD verification and validation are becoming more crucial than ever as more complex ventilation problems are solved. It is anticipated that ventilation problems at the city scale will be tackled by CFD in the next 10 years. © 2011 John Wiley & Sons A/S.

  2. Ventilation through a small-bore catheter: optimizing expiratory ventilation assistance.

    PubMed

    Hamaekers, A E W; Borg, P A J; Götz, T; Enk, D

    2011-03-01

    Emergency ventilation through a small-bore transtracheal catheter can be lifesaving in a 'cannot intubate, cannot ventilate' situation. Ejectors, capable of creating suction by the Bernoulli principle, have been proposed to facilitate expiration through small-bore catheters. In this bench study, we compared a novel, purpose-built ventilation ejector (DE 5) with a previously proposed, modified industrial ejector (SBP 07). The generated insufflation pressures, suction pressures in static and dynamic situations, and also suction capacities and entrainment ratios of the SBP 07 and the DE 5 were determined. The DE 5 was also tested in a lung simulator with a simulated complete upper airway obstruction. Inspiratory and expiratory times through a transtracheal catheter were measured at various flow rates and achievable minute volumes were calculated. In a static situation, the SBP 07 showed a more negative pressure build-up compared with the DE 5. However, in a dynamic situation, the DE 5 generated a more negative pressure, resulting in a higher suction capacity. Employment of the DE 5 at a flow rate of 18 litre min(-1) allowed a minute volume through the transtracheal catheter of up to 8.27 litre min(-1) at a compliance of 100 ml cm H(2)O(-1). The efficiency of the DE 5 depended on the flow rate of the driving gas and the compliance of the lung simulator. In laboratory tests, the DE 5 is an optimized ventilation ejector suitable for applying expiratory ventilation assistance. Further research may confirm the clinical applicability as a portable emergency ventilator for use with small-bore catheters.

  3. Intraoperative mechanical ventilation strategies in patients undergoing one-lung ventilation: a meta-analysis.

    PubMed

    Liu, Zhen; Liu, Xiaowen; Huang, Yuguang; Zhao, Jing

    2016-01-01

    Postoperative pulmonary complications (PPCs), which are not uncommon in one-lung ventilation, are among the main causes of postoperative death after lung surgery. Intra-operative ventilation strategies can influence the incidence of PPCs. High tidal volume (V T) and increased airway pressure may lead to lung injury, while pressure-controlled ventilation and lung-protective strategies with low V T may have protective effects against lung injury. In this meta-analysis, we aim to investigate the effects of different ventilation strategies, including pressure-controlled ventilation (PCV), volume-controlled ventilation (VCV), protective ventilation (PV) and conventional ventilation (CV), on PPCs in patients undergoing one-lung ventilation. We hypothesize that both PV with low V T and PCV have protective effects against PPCs in one-lung ventilation. A systematic search (PubMed, EMBASE, the Cochrane Library, and Ovid MEDLINE; in May 2015) was performed for randomized trials comparing PCV with VCV or comparing PV with CV in one-lung ventilation. Methodological quality was evaluated using the Cochrane tool for risk. The primary outcome was the incidence of PPCs. The secondary outcomes included the length of hospital stay, intraoperative plateau airway pressure (Pplateau), oxygen index (PaO2/FiO2) and mean arterial pressure (MAP). In this meta-analysis, 11 studies (436 patients) comparing PCV with VCV and 11 studies (657 patients) comparing PV with CV were included. Compared to CV, PV decreased the incidence of PPCs (OR 0.29; 95 % CI 0.15-0.57; P < 0.01) and intraoperative Pplateau (MD -3.75; 95 % CI -5.74 to -1.76; P < 0.01) but had no significant influence on the length of hospital stay or MAP. Compared to VCV, PCV decreased intraoperative Pplateau (MD -1.46; 95 % CI -2.54 to -0.34; P = 0.01) but had no significant influence on PPCs, PaO2/FiO2 or MAP. PV with low V T was associated with the reduced incidence of PPCs compared to CV. However, PCV and VCV had similar

  4. Impact of Fire Ventilation on General Ventilation in the Building

    NASA Astrophysics Data System (ADS)

    Zender-Świercz, Ewa; Telejko, Marek

    2017-10-01

    The fire of building is a threat to its users. The biggest threat is generation, during lifetime of fire, hot gases and smoke. The purpose of quick and efficient evacuation from the area covered by the fire, at first step the escape routes have to be secured from smokiness. The smoke ventilation systems are used for this purpose. The proper design and execution of smoke ventilation is important not only because of the safety, but also of the maintenance of comfort in the building at a time when there is no fire. The manuscript presents the effect of incorrectly realized smoke ventilation in the stairwell of the medium building. The analysis shows that the flaps of smoke ventilation located in the stairwell may have a significant impact on the proper functioning of mechanical ventilation in the period when there is no fire. The improperly installed or incorrect insulated components cause perturbation of air flow and they change pressure distribution in the building. The conclusion of the analysis is the need to include the entire technical equipment of the building during the design and realization of its individual elements. The impact of various installations at each other is very important, and the omission of any of them can cause disturbances in the proper work of another.

  5. Trends in mechanical ventilation: are we ventilating our patients in the best possible way?

    PubMed Central

    Veneroni, Chiara; Farre’, Ramon

    2017-01-01

    This review addresses how the combination of physiology, medicine and engineering principles contributed to the development and advancement of mechanical ventilation, emphasising the most urgent needs for improvement and the most promising directions of future development. Several aspects of mechanical ventilation are introduced, highlighting on one side the importance of interdisciplinary research for further development and, on the other, the importance of training physicians sufficiently on the technological aspects of modern devices to exploit properly the great complexity and potentials of this treatment. Educational aims To learn how mechanical ventilation developed in recent decades and to provide a better understanding of the actual technology and practice. To learn how and why interdisciplinary research and competences are necessary for providing the best ventilation treatment to patients. To understand which are the most relevant technical limitations in modern mechanical ventilators that can affect their performance in delivery of the treatment. To better understand and classify ventilation modes. To learn the classification, benefits, drawbacks and future perspectives of automatic ventilation tailoring algorithms. PMID:28620428

  6. Trends in mechanical ventilation: are we ventilating our patients in the best possible way?

    PubMed

    Dellaca', Raffaele L; Veneroni, Chiara; Farre', Ramon

    2017-06-01

    This review addresses how the combination of physiology, medicine and engineering principles contributed to the development and advancement of mechanical ventilation, emphasising the most urgent needs for improvement and the most promising directions of future development. Several aspects of mechanical ventilation are introduced, highlighting on one side the importance of interdisciplinary research for further development and, on the other, the importance of training physicians sufficiently on the technological aspects of modern devices to exploit properly the great complexity and potentials of this treatment. To learn how mechanical ventilation developed in recent decades and to provide a better understanding of the actual technology and practice.To learn how and why interdisciplinary research and competences are necessary for providing the best ventilation treatment to patients.To understand which are the most relevant technical limitations in modern mechanical ventilators that can affect their performance in delivery of the treatment.To better understand and classify ventilation modes.To learn the classification, benefits, drawbacks and future perspectives of automatic ventilation tailoring algorithms.

  7. AF-GEOSPACE Version 2.1

    NASA Astrophysics Data System (ADS)

    Hilmer, R. V.; Ginet, G. P.; Hall, T.; Holeman, E.; Madden, D.; Tautz, M.; Roth, C.

    2004-05-01

    AF-GEOSpace is a graphics-intensive software program with space environment models and applications developed and distributed by the Space Weather Center of Excellence at AFRL. A review of current (Version 2.0) and planned (Version 2.1) AF-GEOSpace capabilities will be given. A wide range of physical domains is represented enabling the software to address such things as solar disturbance propagation, radiation belt configuration, and ionospheric auroral particle precipitation and scintillation. The software is currently being used to aid with the design, operation, and simulation of a wide variety of communications, navigation, and surveillance systems. Building on the success of previous releases, AF-GEOSpace has become a platform for the rapid prototyping of automated operational and simulation space weather visualization products and helps with a variety of tasks, including: orbit specification for radiation hazard avoidance; satellite design assessment and post-event anomaly analysis; solar disturbance effects forecasting; frequency and antenna management for radar and HF communications; determination of link outage regions for active ionospheric conditions; scientific model validation and comparison, physics research, and education. Version 2.0 provided a simplified graphical user interface, improved science and application modules, and significantly enhanced graphical performance. Common input data archive sets, application modules, and 1-D, 2-D, and 3-D visualization tools are provided to all models. Dynamic capabilities permit multiple environments to be generated at user-specified time intervals while animation tools enable displays such as satellite orbits and environment data together as a function of time. Building on the existing Version 2.0 software architecture, AF-GEOSpace Version 2.1 is currently under development and will include a host of new modules to provide, for example, geosynchronous charged particle fluxes, neutral atmosphere densities

  8. Management of atrial fibrillation in Greece: the MANAGE-AF study.

    PubMed

    Andrikopoulos, George; Pastromas, Sokratis; Mantas, Ioannis; Sakellariou, Dimitris; Kyrpizidis, Christos; Makridis, Pantelis; Goumas, Georgios; Stakos, Dimitris; Gotsis, Alexandros; Kartalis, Athanasios; Kazianis, Georgios; Babalis, Dimitrios; Toli, Konstantina; Tzeis, Stylianos; Papavasileiou, Maria; Kalogeropoulos, Petros; Vardas, Panos

    2014-01-01

    Although atrial fibrillation (AF) is a highly prevalent health problem with high morbidity and mortality, data regarding the clinical characteristics and management of AF in the Greek population are scarce. The "Current Clinical Practice in the MANAGEment of Atrial Fibrillation in Greece" study (MANAGEAF) aimed to assess the epidemiological features as well as the daily clinical practice in the management of Greek patients with AF. Taking into consideration the distribution of the Greek population, 603 consecutive patients over 18 years of age, with any type of AF, presenting at the emergency departments or outpatient clinics of 27 different centers, were included in our study. The mean age of the patients was 68.5 ± 12.1 years, with male patients representing 52.5% of the study population. The most common AF type in our cohort was non-paroxysmal AF (60%), including the patients with permanent (24.1%), persistent (17.4%), long-standing (4.8%) and first diagnosed AF (13.8%). Hypertension was the most common comorbidity (70.3%). A history of stroke or transient ischemic attack was detected in 9.2% of the patients, while 6.2% had a history of gastrointestinal bleeding. About half of the patients (49.3%) were treated with anticoagulant drugs, mainly vitamin K antagonists (46.9%), while 34.2% were on antiplatelet drugs, aspirin and/or clopidogrel. The mean INR level (1.7 ± 0.8) was sub-therapeutic, although the mean values for CHADS2 and CHA2DS2-VASc scores were 1.6 ± 1.2 and 3.0 ± 1.7, respectively. The MANAGE-AF baseline results indicate unsatisfactory levels of compliance with the current guidelines for the management of AF in Greece. Considering the undisputed effectiveness of anticoagulant treatment for preventing AF-related strokes, MANAGE-AF demonstrates the need for optimization of our therapeutic strategies for the management of cardioembolic stroke risk.

  9. Daily Goals Formulation and Enhanced Visualization of Mechanical Ventilation Variance Improves Mechanical Ventilation Score.

    PubMed

    Walsh, Brian K; Smallwood, Craig; Rettig, Jordan; Kacmarek, Robert M; Thompson, John; Arnold, John H

    2017-03-01

    The systematic implementation of evidence-based practice through the use of guidelines, checklists, and protocols mitigates the risks associated with mechanical ventilation, yet variation in practice remains prevalent. Recent advances in software and hardware have allowed for the development and deployment of an enhanced visualization tool that identifies mechanical ventilation goal variance. Our aim was to assess the utility of daily goal establishment and a computer-aided visualization of variance. This study was composed of 3 phases: a retrospective observational phase (baseline) followed by 2 prospective sequential interventions. Phase I intervention comprised daily goal establishment of mechanical ventilation. Phase II intervention was the setting and monitoring of daily goals of mechanical ventilation with a web-based data visualization system (T3). A single score of mechanical ventilation was developed to evaluate the outcome. The baseline phase evaluated 130 subjects, phase I enrolled 31 subjects, and phase II enrolled 36 subjects. There were no differences in demographic characteristics between cohorts. A total of 171 verbalizations of goals of mechanical ventilation were completed in phase I. The use of T3 increased by 87% from phase I. Mechanical ventilation score improved by 8.4% in phase I and 11.3% in phase II from baseline ( P = .032). The largest effect was in the low risk V T category, with a 40.3% improvement from baseline in phase I, which was maintained at 39% improvement from baseline in phase II ( P = .01). mechanical ventilation score was 9% higher on average in those who survived. Daily goal formation and computer-enhanced visualization of mechanical ventilation variance were associated with an improvement in goal attainment by evidence of an improved mechanical ventilation score. Further research is needed to determine whether improvements in mechanical ventilation score through a targeted, process-oriented intervention will lead to

  10. High-Frequency Percussive Ventilation Revisited

    DTIC Science & Technology

    2010-01-01

    be implemented. ‡ Follow the reverse of the ventilation sequence if respiratory alkalosis develops—however, start at ventilation goal sequence 1 not at...High-frequency percussive ventilation (HFPV) has demonstrated a potential role as a rescue option for refractory acute respiratory distress syndrome...frequency percussive ventilation (HFPV) has demon- strated a potential role as a salvage option for refrac- tory acute respiratory distress syndrome

  11. The effect of helium on ventilator performance: study of five ventilators and a bedside Pitot tube spirometer.

    PubMed

    Oppenheim-Eden, A; Cohen, Y; Weissman, C; Pizov, R

    2001-08-01

    To assess in vitro the performance of five mechanical ventilators-Siemens 300 and 900C (Siemens-Elma; Solna, Sweden), Puritan Bennett 7200 (Nellcor Puritan Bennett; Pleasanton, CA), Evita 4 (Dragerwerk; Lubeck, Germany), and Bear 1000 (Bear Medical Systems; Riverside CA)-and a bedside sidestream spirometer (Datex CS3 Respiratory Module; Datex-Ohmeda; Helsinki, Finland) during ventilation with helium-oxygen mixtures. In vitro study. ICUs of two university-affiliated hospitals. Each ventilator was connected to 100% helium through compressed air inlets and then tested at three to six different tidal volume (VT) settings using various helium-oxygen concentrations (fraction of inspired oxygen [FIO(2)] of 0.2 to 1.0). FIO(2) and VT were measured with the Datex CS3 spirometer, and VT was validated with a water-displacement spirometer. The Puritan Bennett 7200 ventilator did not function with helium. With the other four ventilators, delivered FIO(2) was lower than the set FIO(2). For the Siemens 300 and 900C ventilators, this difference could be explained by the lack of 21% oxygen when helium was connected to the air supply port, while for the other two ventilators, a nonlinear relation was found. The VT of the Siemens 300 ventilator was independent of helium concentration, while for the other three ventilators, delivered VT was greater than the set VT and was dependent on helium concentration. During ventilation with 80% helium and 20% oxygen, VT increased to 125% of set VT for the Siemens 900C ventilator, and more than doubled for the Evita 4 and Bear 1000 ventilators. Under the same conditions, the Datex CS3 spirometer underestimated the delivered VT by about 33%. At present, no mechanical ventilator is calibrated for use with helium. This investigation offers correction factors for four ventilators for ventilation with helium.

  12. Temperature of gas delivered from ventilators.

    PubMed

    Chikata, Yusuke; Onodera, Mutsuo; Imanaka, Hideaki; Nishimura, Masaji

    2013-01-01

    Although heated humidifiers (HHs) are the most efficient humidifying device for mechanical ventilation, some HHs do not provide sufficient humidification when the inlet temperature to the water chamber is high. Because portable and home-care ventilators use turbines, blowers, pistons, or compressors to inhale in ambient air, they may have higher gas temperature than ventilators with piping systems. We carried out a bench study to investigate the temperature of gas delivered from portable and home-care ventilators, including the effects of distance from ventilator outlet, fraction of inspiratory oxygen (FIO2), and minute volume (MV). We evaluated five ventilators equipped with turbine, blower, piston, or compressor system. Ambient air temperature was adjusted to 24°C ± 0.5°C, and ventilation was set at FIO2 0.21, 0.6, and 1.0, at MV 5 and 10 L/min. We analyzed gas temperature at 0, 40, 80, and 120 cm from ventilator outlet and altered ventilator settings. While temperature varied according to ventilators, the outlet gas temperature of ventilators became stable after, at the most, 5 h. Gas temperature was 34.3°C ± 3.9°C at the ventilator outlet, 29.5°C ± 2.2°C after 40 cm, 25.4°C ± 1.2°C after 80 cm and 25.1°C ± 1.2°C after 120 cm (P < 0.01). FIO2 and MV did not affect gas temperature. Gas delivered from portable and home-care ventilator was not too hot to induce heated humidifier malfunctioning. Gas soon declined when passing through the limb.

  13. 14 CFR 125.117 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Ventilation. 125.117 Section 125.117 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS....117 Ventilation. Each passenger or crew compartment must be suitably ventilated. Carbon monoxide...

  14. Pretest Predictions for Ventilation Tests

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

    Y. Sun; H. Yang; H.N. Kalia

    The objective of this calculation is to predict the temperatures of the ventilating air, waste package surface, concrete pipe walls, and insulation that will be developed during the ventilation tests involving various test conditions. The results will be used as input to the following three areas: (1) Decisions regarding testing set-up and performance. (2) Assessing how best to scale the test phenomena measured. (3) Validating numerical approach for modeling continuous ventilation. The scope of the calculation is to identify the physical mechanisms and parameters related to thermal response in the ventilation tests, and develop and describe numerical methods that canmore » be used to calculate the effects of continuous ventilation. Sensitivity studies to assess the impact of variation of linear power densities (linear heat loads) and ventilation air flow rates are included. The calculation is limited to thermal effect only.« less

  15. 30 CFR 75.333 - Ventilation controls.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Ventilation controls. 75.333 Section 75.333... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.333 Ventilation controls. (a) For... ventilation control devices constructed after November 15, 1992, shall be built and maintained— (1) Between...

  16. 30 CFR 75.333 - Ventilation controls.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Ventilation controls. 75.333 Section 75.333... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.333 Ventilation controls. (a) For... ventilation control devices constructed after November 15, 1992, shall be built and maintained— (1) Between...

  17. Ventilation practices in subarachnoid hemorrhage: a cohort study exploring the use of lung protective ventilation.

    PubMed

    Marhong, Jonathan D; Ferguson, Niall D; Singh, Jeffrey M

    2014-10-01

    Acute respiratory distress syndrome (ARDS) is common following aneurysmal subarachnoid hemorrhage (SAH), but the influence of mechanical ventilator settings on its development is unclear. We sought to determine adherence to lung protective thresholds in ventilated patients with SAH and describe the association between ventilator settings and subsequent development of ARDS. We conducted a retrospective cohort study of consecutive patients receiving mechanical ventilation within 72 h of SAH at a single academic center. Ventilator settings and blood gas data were collected twice daily for the first 7 days of ventilation along with ICU and hospital outcomes. Lung protective ventilation was defined as follows: tidal volume ≤8 mL/kg of predicted body weight, positive end-expiratory pressure (PEEP) ≥5 cm H(2)O, and peak or plateau pressure ≤30 cm H(2)O. The development of ARDS was ascertained retrospectively by PaO(2)/FiO(2) ≤300 with new bilateral lung opacities on chest X-ray within one day of hypoxemia. We identified 62 patients who underwent early mechanical ventilation following SAH. PS and Continuous Positive Airway Pressure were common ventilator modes with a median tidal volume of 7.8 mL/kg [interquartile range 6.8-8.8], median peak pressure of 14 cm H(2)O [IQR 12-17], and median PEEP of 5 cm H(2)O [IQR 5-6]. Adherence to tidal volumes ≤8 mL/kg was seen in 64 % of all observations and peak pressures <30 cm H(2)O were 94 % of all observations. All three lung protective criteria were seen in 58 % of all observations. Thirty-one patients (50 %) were determined to have ARDS. ARDS patients were more frequently ventilated with a peak pressure >30 cm H(2)O (11.3 % of ARDS ventilation days vs. 0 % of non-ARDS ventilation days; p < 0.01). Initial tidal volume was not associated with subsequent development of ARDS in univariate (p = 0.6) or multivariate analysis (p = 0.49). Only the number of ARDS risk factors was independently associated with the development of

  18. Left atrial structure and function in atrial fibrillation: ENGAGE AF-TIMI 48

    PubMed Central

    Gupta, Deepak K.; Shah, Amil M.; Giugliano, Robert P.; Ruff, Christian T.; Antman, Elliott M.; Grip, Laura T.; Deenadayalu, Naveen; Hoffman, Elaine; Patel, Indravadan; Shi, Minggao; Mercuri, Michele; Mitrovic, Veselin; Braunwald, Eugene; Solomon, Scott D.

    2014-01-01

    Aims The complex relationship between left atrial (LA) structure and function, electrical burden of atrial fibrillation (AF) and stroke risk is not well understood. We aimed to describe LA structure and function in AF. Methods and results Left atrial structure and function was assessed in 971 subjects enrolled in the echocardiographic substudy of ENGAGE AF-TIMI 48. Left atrial size, emptying fraction (LAEF), and contractile function were compared across AF types (paroxysmal, persistent, or permanent) and CHADS2 scores as an estimate of stroke risk. The majority of AF patients (55%) had both LA enlargement and reduced LAEF, with an inverse relationship between LA size and LAEF (R = −0.57, P < 0.001). With an increasing electrical burden of AF and higher CHADS2 scores, LA size increased and LAEF declined. Moreover, 19% of AF subjects had impaired LAEF despite normal LA size, and LA contractile dysfunction was present even among the subset of AF subjects in sinus rhythm at the time of echocardiography. Conclusions In a contemporary AF population, LA structure and function were increasingly abnormal with a greater electrical burden of AF and higher stroke risk estimated by the CHADS2 score. Moreover, LA dysfunction was present despite normal LA size and sinus rhythm, suggesting that the assessment of LA function may add important incremental information in the evaluation of AF patients. Clinical Trial Registration: http://www.clinicaltrials.gov; ID = NCT00781391. PMID:24302269

  19. Summary of human responses to ventilation.

    PubMed

    Seppänen, O A; Fisk, W J

    2004-01-01

    It is known that ventilation is necessary to remove indoor-generated pollutants from indoor air or dilute their concentration to acceptable levels. But as the limit values of all pollutants are not known the exact determination of required ventilation rates based on pollutant concentrations is seldom possible. The selection of ventilation rates has to be based also on epidemiological research, laboratory and field experiments and experience. The existing literature indicates that ventilation has a significant impact on several important human outcomes including: (1) communicable respiratory illnesses; (2) sick building syndrome symptoms; (3) task performance and productivity, and (4) perceived air quality (PAQ) among occupants or sensory panels (5) respiratory allergies and asthma. In many studies, prevalence of sick building syndrome symptoms has also been associated with characteristics of HVAC-systems. Often the prevalence of SBS symptoms is higher in air-conditioned buildings than in naturally ventilated buildings. The evidence suggests that better hygiene, commissioning, operation and maintenance of air handling systems may be particularly important for reducing the negative effects of HVAC systems. Ventilation may also have harmful effects on indoor air quality and climate if not properly designed, installed, maintained and operated. Ventilation may bring indoors harmful substances or deteriorate indoor environment. Ventilation interacts also with the building envelope and may deteriorate the structures of the building. Ventilation changes the pressure differences across the structures of building and may cause or prevent infiltration of pollutants from structures or adjacent spaces. Ventilation is also in many cases used to control the thermal environment or humidity in buildings. The paper summarises the current knowledge on positive and negative effects of ventilation on health and other human responses. The focus is on office-type working environment and

  20. 21 CFR 868.5975 - Ventilator tubing.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ventilator tubing. 868.5975 Section 868.5975 Food... DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5975 Ventilator tubing. (a) Identification. Ventilator tubing is a device intended for use as a conduit for gases between a ventilator and a patient...

  1. Ventilating Air-Conditioner

    NASA Technical Reports Server (NTRS)

    Dinh, Khanh

    1994-01-01

    Air-conditioner provides ventilation designed to be used alone or incorporated into cooling or heating system operates efficiently only by recirculating stale air within building. Energy needed to operate overall ventilating cooling or heating system slightly greater than operating nonventilating cooling or heating system. Helps to preserve energy efficiency while satisfying need for increased forced ventilation to prevent accumulation of undesired gases like radon and formaldehyde. Provides fresh treated air to variety of confined spaces: hospital surgeries, laboratories, clean rooms, and printing shops and other places where solvents used. In mobile homes and portable classrooms, eliminates irritant chemicals exuded by carpets, panels, and other materials, ensuring healthy indoor environment for occupants.

  2. Structure and biological activities of eumenine mastoparan-AF (EMP-AF), a new mast cell degranulating peptide in the venom of the solitary wasp (Anterhynchium flavomarginatum micado).

    PubMed

    Konno, K; Hisada, M; Naoki, H; Itagaki, Y; Kawai, N; Miwa, A; Yasuhara, T; Morimoto, Y; Nakata, Y

    2000-11-01

    A new mast cell degranulating peptide, eumenine mastoparan-AF (EMP-AF), was isolated from the venom of the solitary wasp Anterhynchium flavomarginatum micado, the most common eumenine wasp found in Japan. The structure was analyzed by FAB-MS/MS together with Edman degradation, which was corroborated by solid-phase synthesis. The sequence of EMP-AF, Ile-Asn-Leu-Leu-Lys-Ile-Ala-Lys-Gly-Ile-Ile-Lys-Ser-Leu-NH(2), was similar to that of mastoparan, a mast cell degranulating peptide from a hornet venom; tetradecapeptide with C-terminus amidated and rich in hydrophobic and basic amino acids. In fact, EMP-AF exhibited similar activity to mastoparan in stimulating degranulation from rat peritoneal mast cells and RBL-2H3 cells. It also showed significant hemolytic activity in human erythrocytes. Therefore, this is the first example that a mast cell degranulating peptide is found in the solitary wasp venom. Besides the degranulation and hemolytic activity, EMP-AF also affects on neuromuscular transmission in the lobster walking leg preparation. Three analogs EMP-AF-1 approximately 3 were snythesized and biologically tested together with EMP-AF, resulting in the importance of the C-terminal amide structure for biological activities.

  3. Protective garment ventilation system

    NASA Technical Reports Server (NTRS)

    Lang, R. (Inventor)

    1970-01-01

    A method and apparatus for ventilating a protective garment, space suit system, and/or pressure suits to maintain a comfortable and nontoxic atmosphere within is described. The direction of flow of a ventilating and purging gas in portions of the garment may be reversed in order to compensate for changes in environment and activity of the wearer. The entire flow of the ventilating gas can also be directed first to the helmet associated with the garment.

  4. Evidence-based practice: use of the ventilator bundle to prevent ventilator-associated pneumonia.

    PubMed

    Tolentino-DelosReyes, Arlene F; Ruppert, Susan D; Shiao, Shyang-Yun Pamela K

    2007-01-01

    To examine critical care nurses' knowledge about the use of the ventilator bundle to prevent ventilator-associated pneumonia. Published reports were reviewed for current evidence on the use of the ventilator bundle to prevent ventilator-associated pneumonia, and education sessions were held to present the findings to 61 nurses in coronary care and surgical intensive care units. Changes in the nurses' knowledge were evaluated by using a 10-item test, given both before and after the sessions. Changes in the nurses' practices related to ventilator-associated pneumonia, including elevation of the head of the bed to 30 degrees to 45 degrees , were observed in 99 intubated patients. After the education sessions, the nurses performed better on 8 of the 10 items tested (P from .03 to <.001). The areas of most significant improvement were elevation of the head of the bed (P < .001), charting of the elevation of the head of the bed (P= .009), oral care (P= .009), checking of the nasogastric tube for residual volume (P = .008), washing of hands before contact with patients (P < .001), and limiting the wearing of rings (P < .001) and nail polish (P = .04). Even after the education sessions, the nurses' compliance with hand-washing recommendations before contact with patients was low, though statistically some improvement was apparent. Contraindications to elevation of the head of the bed did not appear to affect the nurses' practices (P= .38). Education sessions designed to inform nurses about the ventilator bundle and its use to prevent ventilator-associated pneumonia have a significant effect on participants' knowledge and subsequent clinical practice.

  5. The impact of a ventilator bundle on preventing ventilator-associated pneumonia: a multicenter study.

    PubMed

    Eom, Joong Sik; Lee, Mi-Suk; Chun, Hee-Kyung; Choi, Hee Jung; Jung, Sun-Young; Kim, Yeon-Sook; Yoon, Seon Jin; Kwak, Yee Gyung; Oh, Gang-Bok; Jeon, Min-Hyok; Park, Sun-Young; Koo, Hyun-Sook; Ju, Young-Su; Lee, Jin Seo

    2014-01-01

    For prevention of ventilator-associated pneumonia (VAP), a bundle approach was applied to patients receiving mechanical ventilation in intensive care units. The incidence of VAP and the preventive efficacy of the VAP bundle were investigated. A quasi-experimental study was conducted in adult intensive care units of 6 university hospitals with similar VAP rates. We implemented the VAP bundle between March 2011 and June 2011, then compared the rate of VAP after implementation of the VAP bundle with the rate in the previous 8 months. Our ventilator bundle included head of bed elevation, peptic ulcer disease prophylaxis, deep venous thrombosis prophylaxis, and oral decontamination with chlorhexidine 0.12%. Continuous aspiration of subglottic secretions was an option. Implementation of the VAP bundle reduced the VAP rate from a mean of 4.08 cases per 1,000 ventilator-days to 1.16 cases per 1,000 ventilator-days. The incidence density ratio (rate) was 0.28 (95% confidence interval, 0.275-0.292). Implementing the appropriate VAP bundle significantly decreased the incidence of VAP in patients with mechanical ventilation. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  6. Fungal volatiles associated with moldy grain in ventilated and non-ventilated bin-stored wheat.

    PubMed

    Sinha, R N; Tuma, D; Abramson, D; Muir, W E

    1988-01-01

    The fungal odor compounds 3-methyl-1-butanol, 1-octen-3-ol and 3-octanone were monitored in nine experimental bins in Winnipeg, Manitoba containing a hard red spring wheat during the autumn, winter and summer seasons of 1984-85. Quality changes were associated with seed-borne microflora and moisture content in both ventilated and non-ventilated bins containing wheat of 15.6 and 18.2% initial moisture content. All three odor compounds occurred in considerably greater amounts in bulk wheat in non-ventilated than in ventilated bins, particularly in those with wheat having 18.2% moisture content. The presence of these compounds usually coincided with infection of the seeds by the fungi Alternaria alternata (Fr.) Keissler, Aspergillus repens DeBarry, A. versicolor (Vuill.) Tiraboschi, Penicillium crustosum Thom, P. oxalicum Currie and Thom, P. aurantiogriesum Dierckx, and P. citrinum Thom. High production of all three odor compounds in damp wheat stored in non-ventilated bins was associated with heavy fungal infection of the seeds and reduction in seed germinability. High initial moisture content of the harvested grain accelerated the production of all three fungal volatiles in non-ventilated bins.

  7. Increased Heart Rate Is Associated With Higher Mortality in Patients With Atrial Fibrillation (AF): Results From the Outcomes Registry for Better Informed Treatment of AF (ORBIT-AF)

    PubMed Central

    Steinberg, Benjamin A; Kim, Sunghee; Thomas, Laine; Fonarow, Gregg C; Gersh, Bernard J; Holmqvist, Fredrik; Hylek, Elaine; Kowey, Peter R; Mahaffey, Kenneth W; Naccarelli, Gerald; Reiffel, James A; Chang, Paul; Peterson, Eric D; Piccini, Jonathan P

    2015-01-01

    Background Most patients with atrial fibrillation (AF) require rate control; however, the optimal target heart rate remains under debate. We aimed to assess rate control and subsequent outcomes among patients with permanent AF. Methods and Results We studied 2812 US outpatients with permanent AF in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation. Resting heart rate was measured longitudinally and used as a time-dependent covariate in multivariable Cox models of all-cause and cause-specific mortality during a median follow-up of 24 months. At baseline, 7.4% (n=207) had resting heart rate <60 beats per minute (bpm), 62% (n=1755) 60 to 79 bpm, 29% (n=817) 80 to 109 bpm, and 1.2% (n=33) ≥110 bpm. Groups did not differ by age, previous cerebrovascular disease, heart failure status, CHA2DS2-VASc scores, renal function, or left ventricular function. There were significant differences in race (P=0.001), sinus node dysfunction (P=0.004), and treatment with calcium-channel blockers (P=0.006) and anticoagulation (P=0.009). In analyses of continuous heart rates, lower heart rate ≤65 bpm was associated with higher all-cause mortality (adjusted hazard ratio [HR], 1.15 per 5-bpm decrease; 95% CI, 1.01 to 1.32; P=0.04). Similarly, increasing heart rate >65 bpm was associated with higher all-cause mortality (adjusted HR, 1.10 per 5-bpm increase; 95% CI, 1.05 to 1.15; P<0.0001). This relationship was consistent across endpoints and in a broader sensitivity analysis of permanent and nonpermanent AF patients. Conclusions Among patients with permanent AF, there is a J-shaped relationship between heart rate and mortality. These data support current guideline recommendations, and clinical trials are warranted to determine optimal rate control. Clinical Trial Registration URL: http://clinicaltrials.gov/. Unique identifier: NCT01165710. PMID:26370445

  8. Increased Heart Rate Is Associated With Higher Mortality in Patients With Atrial Fibrillation (AF): Results From the Outcomes Registry for Better Informed Treatment of AF (ORBIT-AF).

    PubMed

    Steinberg, Benjamin A; Kim, Sunghee; Thomas, Laine; Fonarow, Gregg C; Gersh, Bernard J; Holmqvist, Fredrik; Hylek, Elaine; Kowey, Peter R; Mahaffey, Kenneth W; Naccarelli, Gerald; Reiffel, James A; Chang, Paul; Peterson, Eric D; Piccini, Jonathan P

    2015-09-14

    Most patients with atrial fibrillation (AF) require rate control; however, the optimal target heart rate remains under debate. We aimed to assess rate control and subsequent outcomes among patients with permanent AF. We studied 2812 US outpatients with permanent AF in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation. Resting heart rate was measured longitudinally and used as a time-dependent covariate in multivariable Cox models of all-cause and cause-specific mortality during a median follow-up of 24 months. At baseline, 7.4% (n=207) had resting heart rate <60 beats per minute (bpm), 62% (n=1755) 60 to 79 bpm, 29% (n=817) 80 to 109 bpm, and 1.2% (n=33) ≥110 bpm. Groups did not differ by age, previous cerebrovascular disease, heart failure status, CHA2DS2-VASc scores, renal function, or left ventricular function. There were significant differences in race (P=0.001), sinus node dysfunction (P=0.004), and treatment with calcium-channel blockers (P=0.006) and anticoagulation (P=0.009). In analyses of continuous heart rates, lower heart rate ≤65 bpm was associated with higher all-cause mortality (adjusted hazard ratio [HR], 1.15 per 5-bpm decrease; 95% CI, 1.01 to 1.32; P=0.04). Similarly, increasing heart rate >65 bpm was associated with higher all-cause mortality (adjusted HR, 1.10 per 5-bpm increase; 95% CI, 1.05 to 1.15; P<0.0001). This relationship was consistent across endpoints and in a broader sensitivity analysis of permanent and nonpermanent AF patients. Among patients with permanent AF, there is a J-shaped relationship between heart rate and mortality. These data support current guideline recommendations, and clinical trials are warranted to determine optimal rate control. URL: http://clinicaltrials.gov/. Unique identifier: NCT01165710. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  9. Mechanical ventilation for severe asthma.

    PubMed

    Leatherman, James

    2015-06-01

    Acute exacerbations of asthma can lead to respiratory failure requiring ventilatory assistance. Noninvasive ventilation may prevent the need for endotracheal intubation in selected patients. For patients who are intubated and undergo mechanical ventilation, a strategy that prioritizes avoidance of ventilator-related complications over correction of hypercapnia was first proposed 30 years ago and has become the preferred approach. Excessive pulmonary hyperinflation is a major cause of hypotension and barotrauma. An appreciation of the key determinants of hyperinflation is essential to rational ventilator management. Standard therapy for patients with asthma undergoing mechanical ventilation consists of inhaled bronchodilators, corticosteroids, and drugs used to facilitate controlled hypoventilation. Nonconventional interventions such as heliox, general anesthesia, bronchoscopy, and extracorporeal life support have also been advocated for patients with fulminant asthma but are rarely necessary. Immediate mortality for patients who are mechanically ventilated for acute severe asthma is very low and is often associated with out-of-hospital cardiorespiratory arrest before intubation. However, patients who have been intubated for severe asthma are at increased risk for death from subsequent exacerbations and must be managed accordingly in the outpatient setting.

  10. Wind Extraction for Natural Ventilation

    NASA Astrophysics Data System (ADS)

    Fagundes, Tadeu; Yaghoobian, Neda; Kumar, Rajan; Ordonez, Juan

    2017-11-01

    Due to the depletion of energy resources and the environmental impact of pollution and unsustainable energy resources, energy consumption has become one of the main concerns in our rapidly growing world. Natural ventilation, a traditional method to remove anthropogenic and solar heat gains, proved to be a cost-effective, alternative method to mechanical ventilation. However, while natural ventilation is simple in theory, its detailed design can be a challenge, particularly for wind-driven ventilation, which its performance highly involves the buildings' form, surrounding topography, turbulent flow characteristics, and climate. One of the main challenges with wind-driven natural ventilation schemes is due to the turbulent and unpredictable nature of the wind around the building that impose complex pressure loads on the structure. In practice, these challenges have resulted in founding the natural ventilation mainly on buoyancy (rather than the wind), as the primary force. This study is the initial step for investigating the physical principals of wind extraction over building walls and investigating strategies to reduce the dependence of the wind extraction on the incoming flow characteristics and the target building form.

  11. Tatalina AFS, Alaska. Revised Uniform Summary of Surface Weather Observations (RUSSWO). Parts A-F.

    DTIC Science & Technology

    1983-03-01

    M’CROCOpy pESLUTONEST CkA~l PH THIS SHEET Af) m r’",I "er-"i cprit, r I ~~~~Tahen 01.-ing ,lt c’, ’ .c,- us. Bel ii % owe i -r LEVEL ~ut with Ier r iNVENTORY...82172 MAR N 62 53 W V558 ELV: 964 FT PAT. PAinTS A-F HOURS SU M &UZED: OOOOZ - 230OZ PER{IOD OF RECORD: HOUPLY OBSERYATION.1: JAN 73 - DEC 81 SLW4MAY OF...NOVEM_ _ _ _ .._ ,- .- ,z. 702315 SA A. i. ts 58 9 STATION LOCATION AND INS’rRUMtNTATION ,HI STORY NUr! TIf E 11T to tw ITLmU am M GS of CEO(IAPNICAL

  12. Comparison between conventional and protective one-lung ventilation for ventilator-assisted thoracic surgery.

    PubMed

    Ahn, H J; Kim, J A; Yang, M; Shim, W S; Park, K J; Lee, J J

    2012-09-01

    Recent papers suggest protective ventilation (PV) as a primary ventilation strategy during one-lung ventilation (OLV) to reduce postoperative pulmonary morbidity. However, data regarding the advantage of the PV strategy in patients with normal preoperative pulmonary function are inconsistent, especially in the case of minimally invasive thoracic surgery. Therefore we compared conventional OLV (VT 10 ml/kg, FiO2 1.0, zero PEEP) to protective OLV (VT 6 ml/kg, FiO2 0.5, PEEP 5 cmH2O) in patients with normal preoperative pulmonary function tests undergoing video-assisted thoracic surgery. Oxygenation, respiratory mechanics, plasma interleukin-6 and malondialdehyde levels were measured at baseline, 15 and 60 minutes after OLV and 15 minutes after restoration of two-lung ventilation. PaO2 and PaO2/FiO2 were higher in conventional OLV than in protective OLV (P<0.001). Interleukin-6 and malondialdehyde increased over time in both groups (P<0.05); however, the magnitudes of increase were not different between the groups. Postoperatively there were no differences in the number of patients with PaO2/FiO2<300 mmHg or abnormalities on chest radiography. Protective ventilation did not provide advantages over conventional ventilation for video-assisted thoracic surgery in this group of patients with normal lung function.

  13. Sparrevohn AFS, Alaska. Revised Uniform Summary of Surface Weather Observations.

    DTIC Science & Technology

    1985-09-18

    SSURFACE WEATHER OBSERVATIONS SPARREVOHN AFS AK MSC #702350 N 61 06 W155 35 ELEV: 1573 FT PASV PARTS A-F HOURS SUMMARIZED: 0000 - 2300 LST PERIOD OF RECORD...stations around the world. This is the provenance of the number (e.g., MSC 999999) which will appear on future OL-A standard products. D I...AFS Af PEt 7oif of [ COPD : 77-84 MONTH: A W, HO URS4LS3: ALL 7.3 itIts 816181L1F7 IN 6FAFLIF WILCS INs ((I (F IF F G CF b t I, [ CF ŕ 6 1 ,F F F tF7F I

  14. Optimal ventilation of the anesthetized pediatric patient.

    PubMed

    Feldman, Jeffrey M

    2015-01-01

    Mechanical ventilation of the pediatric patient is challenging because small changes in delivered volume can be a significant fraction of the intended tidal volume. Anesthesia ventilators have traditionally been poorly suited to delivering small tidal volumes accurately, and pressure-controlled ventilation has become used commonly when caring for pediatric patients. Modern anesthesia ventilators are designed to deliver small volumes accurately to the patient's airway by compensating for the compliance of the breathing system and delivering tidal volume independent of fresh gas flow. These technology advances provide the opportunity to implement a lung-protective ventilation strategy in the operating room based upon control of tidal volume. This review will describe the capabilities of the modern anesthesia ventilator and the current understanding of lung-protective ventilation. An optimal approach to mechanical ventilation for the pediatric patient is described, emphasizing the importance of using bedside monitors to optimize the ventilation strategy for the individual patient.

  15. New modes of assisted mechanical ventilation.

    PubMed

    Suarez-Sipmann, F

    2014-05-01

    Recent major advances in mechanical ventilation have resulted in new exciting modes of assisted ventilation. Compared to traditional ventilation modes such as assisted-controlled ventilation or pressure support ventilation, these new modes offer a number of physiological advantages derived from the improved patient control over the ventilator. By implementing advanced closed-loop control systems and using information on lung mechanics, respiratory muscle function and respiratory drive, these modes are specifically designed to improve patient-ventilator synchrony and reduce the work of breathing. Depending on their specific operational characteristics, these modes can assist spontaneous breathing efforts synchronically in time and magnitude, adapt to changing patient demands, implement automated weaning protocols, and introduce a more physiological variability in the breathing pattern. Clinicians have now the possibility to individualize and optimize ventilatory assistance during the complex transition from fully controlled to spontaneous assisted ventilation. The growing evidence of the physiological and clinical benefits of these new modes is favoring their progressive introduction into clinical practice. Future clinical trials should improve our understanding of these modes and help determine whether the claimed benefits result in better outcomes. Copyright © 2013 Elsevier España, S.L. and SEMICYUC. All rights reserved.

  16. Mechanical ventilation in abdominal surgery.

    PubMed

    Futier, E; Godet, T; Millot, A; Constantin, J-M; Jaber, S

    2014-01-01

    One of the key challenges in perioperative care is to reduce postoperative morbidity and mortality. Patients who develop postoperative morbidity but survive to leave hospital have often reduced functional independence and long-term survival. Mechanical ventilation provides a specific example that may help us to shift thinking from treatment to prevention of postoperative complications. Mechanical ventilation in patients undergoing surgery has long been considered only as a modality to ensure gas exchange while allowing maintenance of anesthesia with delivery of inhaled anesthetics. Evidence is accumulating, however, suggesting an association between intraoperative mechanical ventilation strategy and postoperative pulmonary function and clinical outcome in patients undergoing abdominal surgery. Non-protective ventilator settings, especially high tidal volume (VT) (>10-12mL/kg) and the use of very low level of positive end-expiratory pressure (PEEP) (PEEP<5cmH2O) or no PEEP, may cause alveolar overdistension and repetitive tidal recruitment leading to ventilator-associated lung injury in patients with healthy lungs. Stimulated by previous findings in patients with acute respiratory distress syndrome, the use of lower tidal volume ventilation is becoming increasingly more common in the operating room. However, lowering tidal volume, though important, is only part of the overall multifaceted approach of lung protective mechanical ventilation. In this review, we aimed at providing the most recent and relevant clinical evidence regarding the use of mechanical ventilation in patients undergoing abdominal surgery. Copyright © 2014 Société française d’anesthésie et de réanimation (Sfar). Published by Elsevier SAS. All rights reserved.

  17. The Role of U2AF1 Mutations in the Pathogenesis of Myelodysplastic Syndromes

    DTIC Science & Technology

    2015-10-01

    mutation, U2AF1(S34F), on hematopoiesis and pre-mRNA splicing in vivo, we created doxycycline-inducible U2AF1(WT) and U2AF1(S34F) transgenic mice...U2AF1(S34F) versus U2AF1(WT). Together, these results suggest that mutant U2AF1 expression contributes to the altered hematopoiesis and pre-mRNA...Spliceosome, Mouse Model, Hematopoiesis , RNA-seq, U2AF1 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME

  18. Comparison between conventional protective mechanical ventilation and high-frequency oscillatory ventilation associated with the prone position.

    PubMed

    Fioretto, José Roberto; Klefens, Susiane Oliveira; Pires, Rafaelle Fernandes; Kurokawa, Cilmery Suemi; Carpi, Mario Ferreira; Bonatto, Rossano César; Moraes, Marcos Aurélio; Ronchi, Carlos Fernando

    2017-01-01

    To compare the effects of high-frequency oscillatory ventilation and conventional protective mechanical ventilation associated with the prone position on oxygenation, histology and pulmonary oxidative damage in an experimental model of acute lung injury. Forty-five rabbits with tracheostomy and vascular access were underwent mechanical ventilation. Acute lung injury was induced by tracheal infusion of warm saline. Three experimental groups were formed: healthy animals + conventional protective mechanical ventilation, supine position (Control Group; n = 15); animals with acute lung injury + conventional protective mechanical ventilation, prone position (CMVG; n = 15); and animals with acute lung injury + high-frequency oscillatory ventilation, prone position (HFOG; n = 15). Ten minutes after the beginning of the specific ventilation of each group, arterial gasometry was collected, with this timepoint being called time zero, after which the animal was placed in prone position and remained in this position for 4 hours. Oxidative stress was evaluated by the total antioxidant performance assay. Pulmonary tissue injury was determined by histopathological score. The level of significance was 5%. Both groups with acute lung injury showed worsening of oxygenation after induction of injury compared with the Control Group. After 4 hours, there was a significant improvement in oxygenation in the HFOG group compared with CMVG. Analysis of total antioxidant performance in plasma showed greater protection in HFOG. HFOG had a lower histopathological lesion score in lung tissue than CMVG. High-frequency oscillatory ventilation, associated with prone position, improves oxygenation and attenuates oxidative damage and histopathological lung injury compared with conventional protective mechanical ventilation.

  19. Comparison between conventional protective mechanical ventilation and high-frequency oscillatory ventilation associated with the prone position

    PubMed Central

    Fioretto, José Roberto; Klefens, Susiane Oliveira; Pires, Rafaelle Fernandes; Kurokawa, Cilmery Suemi; Carpi, Mario Ferreira; Bonatto, Rossano César; Moraes, Marcos Aurélio; Ronchi, Carlos Fernando

    2017-01-01

    Objective To compare the effects of high-frequency oscillatory ventilation and conventional protective mechanical ventilation associated with the prone position on oxygenation, histology and pulmonary oxidative damage in an experimental model of acute lung injury. Methods Forty-five rabbits with tracheostomy and vascular access were underwent mechanical ventilation. Acute lung injury was induced by tracheal infusion of warm saline. Three experimental groups were formed: healthy animals + conventional protective mechanical ventilation, supine position (Control Group; n = 15); animals with acute lung injury + conventional protective mechanical ventilation, prone position (CMVG; n = 15); and animals with acute lung injury + high-frequency oscillatory ventilation, prone position (HFOG; n = 15). Ten minutes after the beginning of the specific ventilation of each group, arterial gasometry was collected, with this timepoint being called time zero, after which the animal was placed in prone position and remained in this position for 4 hours. Oxidative stress was evaluated by the total antioxidant performance assay. Pulmonary tissue injury was determined by histopathological score. The level of significance was 5%. Results Both groups with acute lung injury showed worsening of oxygenation after induction of injury compared with the Control Group. After 4 hours, there was a significant improvement in oxygenation in the HFOG group compared with CMVG. Analysis of total antioxidant performance in plasma showed greater protection in HFOG. HFOG had a lower histopathological lesion score in lung tissue than CMVG. Conclusion High-frequency oscillatory ventilation, associated with prone position, improves oxygenation and attenuates oxidative damage and histopathological lung injury compared with conventional protective mechanical ventilation. PMID:29236845

  20. SU-F-J-219: Predicting Ventilation Change Due to Radiation Therapy: Dependency On Pre-RT Ventilation and Effort Correction

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

    Patton, T; Du, K; Bayouth, J

    Purpose: Ventilation change caused by radiation therapy (RT) can be predicted using four-dimensional computed tomography (4DCT) and image registration. This study tested the dependency of predicted post-RT ventilation on effort correction and pre-RT lung function. Methods: Pre-RT and 3 month post-RT 4DCT images were obtained for 13 patients. The 4DCT images were used to create ventilation maps using a deformable image registration based Jacobian expansion calculation. The post-RT ventilation maps were predicted in four different ways using the dose delivered, pre-RT ventilation, and effort correction. The pre-RT ventilation and effort correction were toggled to determine dependency. The four different predictedmore » ventilation maps were compared to the post-RT ventilation map calculated from image registration to establish the best prediction method. Gamma pass rates were used to compare the different maps with the criteria of 2mm distance-to-agreement and 6% ventilation difference. Paired t-tests of gamma pass rates were used to determine significant differences between the maps. Additional gamma pass rates were calculated using only voxels receiving over 20 Gy. Results: The predicted post-RT ventilation maps were in agreement with the actual post-RT maps in the following percentage of voxels averaged over all subjects: 71% with pre-RT ventilation and effort correction, 69% with no pre-RT ventilation and effort correction, 60% with pre-RT ventilation and no effort correction, and 58% with no pre-RT ventilation and no effort correction. When analyzing only voxels receiving over 20 Gy, the gamma pass rates were respectively 74%, 69%, 65%, and 55%. The prediction including both pre- RT ventilation and effort correction was the only prediction with significant improvement over using no prediction (p<0.02). Conclusion: Post-RT ventilation is best predicted using both pre-RT ventilation and effort correction. This is the only prediction that provided a significant

  1. Effects of Multiple Ventilation Courses and Duration of Mechanical Ventilation on Respiratory Outcomes in Extremely Low-Birth-Weight Infants.

    PubMed

    Jensen, Erik A; DeMauro, Sara B; Kornhauser, Michael; Aghai, Zubair H; Greenspan, Jay S; Dysart, Kevin C

    2015-11-01

    Extubation failure is common in extremely preterm infants. The current paucity of data on the adverse long-term respiratory outcomes associated with reinitiation of mechanical ventilation prevents assessment of the risks and benefits of a trial of extubation in this population. To evaluate whether exposure to multiple courses of mechanical ventilation increases the risk of adverse respiratory outcomes before and after adjustment for the cumulative duration of mechanical ventilation. We performed a retrospective cohort study of extremely low-birth-weight (ELBW; birth weight <1000 g) infants born from January 1, 2006, through December 31, 2012, who were receiving mechanical ventilation. Analysis was conducted between November 2014 and February 2015. Data were obtained from the Alere Neonatal Database. The primary study exposures were the cumulative duration of mechanical ventilation and the number of ventilation courses. The primary outcome was bronchopulmonary dysplasia (BPD) among survivors. Secondary outcomes were death, use of supplemental oxygen at discharge, and tracheostomy. We identified 3343 ELBW infants, of whom 2867 (85.8%) survived to discharge. Among the survivors, 1695 (59.1%) were diagnosed as having BPD, 856 (29.9%) received supplemental oxygen at discharge, and 31 (1.1%) underwent tracheostomy. Exposure to a greater number of mechanical ventilation courses was associated with a progressive increase in the risk of BPD and use of supplemental oxygen at discharge. Compared with a single ventilation course, the adjusted odds ratios for BPD ranged from 1.88 (95% CI, 1.54-2.31) among infants with 2 ventilation courses to 3.81 (95% CI, 2.88-5.04) among those with 4 or more courses. After adjustment for the cumulative duration of mechanical ventilation, the odds of BPD were only increased among infants exposed to 4 or more ventilation courses (adjusted odds ratio, 1.44; 95% CI, 1.04-2.01). The number of ventilation courses was not associated with increased

  2. Night ventilation control strategies in office buildings

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

    Wang, Zhaojun; Yi, Lingli; Gao, Fusheng

    2009-10-15

    In moderate climates night ventilation is an effective and energy-efficient approach to improve the indoor thermal environment for office buildings during the summer months, especially for heavyweight construction. However, is night ventilation a suitable strategy for office buildings with lightweight construction located in cold climates? In order to answer this question, the whole energy-consumption analysis software EnergyPlus was used to simulate the indoor thermal environment and energy consumption in typical office buildings with night mechanical ventilation in three cities in northern China. The summer outdoor climate data was analyzed, and three typical design days were chosen. The most important factorsmore » influencing night ventilation performance such as ventilation rates, ventilation duration, building mass and climatic conditions were evaluated. When night ventilation operation time is closer to active cooling time, the efficiency of night ventilation is higher. With night ventilation rate of 10 ach, the mean radiant temperature of the indoor surface decreased by up to 3.9 C. The longer the duration of operation, the more efficient the night ventilation strategy becomes. The control strategies for three locations are given in the paper. Based on the optimized strategies, the operation consumption and fees are calculated. The results show that more energy is saved in office buildings cooled by a night ventilation system in northern China than ones that do not employ this strategy. (author)« less

  3. Cloning and characterization of two duplicated interleukin-17A/F2 genes in common carp (Cyprinus carpio L.): Transcripts expression and bioactivity of recombinant IL-17A/F2.

    PubMed

    Li, Hongxia; Yu, Juhua; Li, Jianlin; Tang, Yongkai; Yu, Fan; Zhou, Jie; Yu, Wenjuan

    2016-04-01

    Interleukin-17 (IL-17) plays an important role in inflammation and host defense in mammals. In this study, we identified two duplicated IL-17A/F2 genes in the common carp (Cyprinus carpio) (ccIL-17A/F2a and ccIL-17A/F2b), putative encoded proteins contain 140 amino acids (aa) with conserved IL-17 family motifs. Expression analysis revealed high constitutive expression of ccIL-17A/F2s in mucosal tissues, including gill, skin and intestine, their expression could be induced by Aeromonas hydrophila, suggesting a potential role in mucosal immunity. Recombinant ccIL-17A/F2a protein (rccIL-17A/F2a) produced in Escherichia coli could induce the expression of proinflammatory cytokines (IL-1β) and the antimicrobial peptides S100A1, S100A10a and S100A10b in the primary kidney in a dose- and time-dependent manner. Above findings suggest that ccIL-17A/F2 plays an important role in both proinflammatory and innate immunity. Two duplicated ccIL-17A/F2s showed different expression level with ccIL-17A/F2a higher than b, comparison of two 5' regulatory regions indicated the length from anticipated promoter to transcriptional start site (TSS) and putative transcription factor binding site (TFBS) were different. Promoter activity of ccIL-17A/F2a was 2.5 times of ccIL-17A/F2b which consistent with expression results of two genes. These suggest mutations in 5'regulatory region contributed to the differentiation of duplicated genes. To our knowledge, this is the first report to analyze 5'regulatory region of piscine IL-17 family genes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Mechanical ventilation during extracorporeal membrane oxygenation.

    PubMed

    Schmidt, Matthieu; Pellegrino, Vincent; Combes, Alain; Scheinkestel, Carlos; Cooper, D Jamie; Hodgson, Carol

    2014-01-21

    The timing of extracorporeal membrane oxygenation (ECMO) initiation and its outcome in the management of respiratory and cardiac failure have received considerable attention, but very little attention has been given to mechanical ventilation during ECMO. Mechanical ventilation settings in non-ECMO studies have been shown to have an effect on survival and may also have contributed to a treatment effect in ECMO trials. Protective lung ventilation strategies established for non-ECMO-supported respiratory failure patients may not be optimal for more severe forms of respiratory failure requiring ECMO support. The influence of positive end-expiratory pressure on the reduction of the left ventricular compliance may be a matter of concern for patients receiving ECMO support for cardiac failure. The objectives of this review were to describe potential mechanisms for lung injury during ECMO for respiratory or cardiac failure, to assess the possible benefits from the use of ultra-protective lung ventilation strategies and to review published guidelines and expert opinions available on mechanical ventilation-specific management of patients requiring ECMO, including mode and ventilator settings. Articles were identified through a detailed search of PubMed, Ovid, Cochrane databases and Google Scholar. Additional references were retrieved from the selected studies. Growing evidence suggests that mechanical ventilation settings are important in ECMO patients to minimize further lung damage and improve outcomes. An ultra-protective ventilation strategy may be optimal for mechanical ventilation during ECMO for respiratory failure. The effects of airway pressure on right and left ventricular afterload should be considered during venoarterial ECMO support of cardiac failure. Future studies are needed to better understand the potential impact of invasive mechanical ventilation modes and settings on outcomes.

  5. Mechanical ventilation during extracorporeal membrane oxygenation

    PubMed Central

    2014-01-01

    The timing of extracorporeal membrane oxygenation (ECMO) initiation and its outcome in the management of respiratory and cardiac failure have received considerable attention, but very little attention has been given to mechanical ventilation during ECMO. Mechanical ventilation settings in non-ECMO studies have been shown to have an effect on survival and may also have contributed to a treatment effect in ECMO trials. Protective lung ventilation strategies established for non-ECMO-supported respiratory failure patients may not be optimal for more severe forms of respiratory failure requiring ECMO support. The influence of positive end-expiratory pressure on the reduction of the left ventricular compliance may be a matter of concern for patients receiving ECMO support for cardiac failure. The objectives of this review were to describe potential mechanisms for lung injury during ECMO for respiratory or cardiac failure, to assess the possible benefits from the use of ultra-protective lung ventilation strategies and to review published guidelines and expert opinions available on mechanical ventilation-specific management of patients requiring ECMO, including mode and ventilator settings. Articles were identified through a detailed search of PubMed, Ovid, Cochrane databases and Google Scholar. Additional references were retrieved from the selected studies. Growing evidence suggests that mechanical ventilation settings are important in ECMO patients to minimize further lung damage and improve outcomes. An ultra-protective ventilation strategy may be optimal for mechanical ventilation during ECMO for respiratory failure. The effects of airway pressure on right and left ventricular afterload should be considered during venoarterial ECMO support of cardiac failure. Future studies are needed to better understand the potential impact of invasive mechanical ventilation modes and settings on outcomes. PMID:24447458

  6. Lung-protective ventilation in abdominal surgery.

    PubMed

    Futier, Emmanuel; Jaber, Samir

    2014-08-01

    To provide the most recent and relevant clinical evidence regarding the use of prophylactic lung-protective mechanical ventilation in abdominal surgery. Evidence is accumulating, suggesting an association between intraoperative mechanical ventilation strategy and postoperative pulmonary complications in patients undergoing abdominal surgery. Nonprotective ventilator settings, especially high tidal volume (>10-12 ml/kg), very low level of positive end-expiratory pressure (PEEP, <5 cm H2O), or no PEEP, may cause alveolar overdistension and repetitive tidal recruitment leading to ventilator-associated lung injury in patients with healthy lungs. Stimulated by the previous findings in patients with acute respiratory distress syndrome, the use of lower tidal volume ventilation is becoming increasingly more common in the operating room. However, lowering tidal volume, though important, is only part of the overall multifaceted approach of lung-protective mechanical ventilation. Recent data provide compelling evidence that prophylactic lung-protective mechanical ventilation using lower tidal volume (6-8 ml/kg of predicted body weight), moderate PEEP (6-8 cm H2O), and recruitment maneuvers is associated with improved functional or physiological and clinical postoperative outcome in patients undergoing abdominal surgery. The use of prophylactic lung-protective ventilation can help in improving the postoperative outcome.

  7. [Mechanical ventilation in acute asthma crisis].

    PubMed

    Barbas, Carmen Sílvia Valente; Pinheiro, Bruno do Valle; Vianna, Arthur; Magaldi, Ricardo; Casati, Ana; José, Anderson; Okamoto, Valdelis Novis

    2007-06-01

    The II Brazilian Consensus Conference on Mechanical Ventilation was published in 2000. Knowledge on the field of mechanical ventilation evolved rapidly since then, with the publication of numerous clinical studies with potential impact on the ventilatory management of critically ill patients. Moreover, the evolving concept of evidence - based medicine determined the grading of clinical recommendations according to the methodological value of the studies on which they are based. This explicit approach has broadened the understanding and adoption of clinical recommendations. For these reasons, AMIB - Associação de Medicina Intensiva Brasileira and SBPT - Sociedade Brasileira de Pneumologia e Tisiologia - decided to update the recommendations of the II Brazilian Consensus. Mechanical ventilation in the asthma attack has been one of the updated topics. Describe the most important topics on the mechanical ventilation during the asthma attack and suggest the main therapeutic approaches. Systematic review of the published literature and gradation of the studies in levels of evidence, using the key words "mechanical ventilation" and "asthma". We present recommendations on the ventilatory modes and settings to be adopted when ventilating a patient during an asthma attack, as well as the recommended monitoring. Alternative ventilation techniques are also presented. Protective ventilatory strategies are recommended when ventilating a patient during a severe asthma attack.

  8. Sensor-based demand controlled ventilation

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

    De Almeida, A.T.; Fisk, W.J.

    In most buildings, occupancy and indoor pollutant emission rates vary with time. With sensor-based demand-controlled ventilation (SBDCV), the rate of ventilation (i.e., rate of outside air supply) also varies with time to compensate for the changes in pollutant generation. In other words, SBDCV involves the application of sensing, feedback and control to modulate ventilation. Compared to ventilation without feedback, SBDCV offers two potential advantages: (1) better control of indoor pollutant concentrations; and (2) lower energy use and peak energy demand. SBDCV has the potential to improve indoor air quality by increasing the rate of ventilation when indoor pollutant generation ratesmore » are high and occupants are present. SBDCV can also save energy by decreasing the rate of ventilation when indoor pollutant generation rates are low or occupants are absent. After providing background information on indoor air quality and ventilation, this report provides a relatively comprehensive discussion of SBDCV. Topics covered in the report include basic principles of SBDCV, sensor technologies, technologies for controlling air flow rates, case studies of SBDCV, application of SBDCV to laboratory buildings, and research needs. SBDCV appears to be an increasingly attractive technology option. Based on the review of literature and theoretical considerations, the application of SBDCV has the potential to be cost-effective in applications with the following characteristics: (a) a single or small number of dominant pollutants, so that ventilation sufficient to control the concentration of the dominant pollutants provides effective control of all other pollutants; (b) large buildings or rooms with unpredictable temporally variable occupancy or pollutant emission; and (c) climates with high heating or cooling loads or locations with expensive energy.« less

  9. The fluid mechanics of natural ventilation

    NASA Astrophysics Data System (ADS)

    Linden, Paul

    1999-11-01

    Natural ventilation of buildings is the flow generated by temperature differences and by the wind. Modern buildings have extreme designs with large, tall open plan spaces and large cooling requirements. Natural ventilation offers a means of cooling these buildings and providing good indoor air quality. The essential feature of ventilation is an exchange between an interior space and the external ambient. Recent work shows that in many circumstances temperature variations play a controlling feature on the ventilation since the directional buoyancy force has a large influence on the flow patterns within the space and on the nature of the exchange with the outside. Two forms of buoyancy-driven ventilation are discussed: mixing ventilation in which the interior is at approximately uniform temperature and displacement ventilation where there is strong internal stratification. The dynamics of these flows are considered and the effects of wind on them are examined both experimentally and theoretically. The aim behind this work is to give designers rules and intuition on how air moves within a building and the research shows a fascinating branch of fluid mechanics.

  10. Epidemiology of Noninvasive Ventilation in Pediatric Cardiac ICUs.

    PubMed

    Romans, Ryan A; Schwartz, Steven M; Costello, John M; Chanani, Nikhil K; Prodhan, Parthak; Gazit, Avihu Z; Smith, Andrew H; Cooper, David S; Alten, Jeffrey; Mistry, Kshitij P; Zhang, Wenying; Donohue, Janet E; Gaies, Michael

    2017-10-01

    To describe the epidemiology of noninvasive ventilation therapy for patients admitted to pediatric cardiac ICUs and to assess practice variation across hospitals. Retrospective cohort study using prospectively collected clinical registry data. Pediatric Cardiac Critical Care Consortium clinical registry. Patients admitted to cardiac ICUs at PC4 hospitals. None. We analyzed all cardiac ICU encounters that included any respiratory support from October 2013 to December 2015. Noninvasive ventilation therapy included high flow nasal cannula and positive airway pressure support. We compared patient and, when relevant, perioperative characteristics of those receiving noninvasive ventilation to all others. Subgroup analysis was performed on neonates and infants undergoing major cardiovascular surgery. To examine duration of respiratory support, we created a casemix-adjustment model and calculated adjusted mean durations of total respiratory support (mechanical ventilation + noninvasive ventilation), mechanical ventilation, and noninvasive ventilation. We compared adjusted duration of support across hospitals. The cohort included 8,940 encounters from 15 hospitals: 3,950 (44%) received noninvasive ventilation and 72% were neonates and infants. Medical encounters were more likely to include noninvasive ventilation than surgical. In surgical neonates and infants, 2,032 (55%) received postoperative noninvasive ventilation. Neonates, extracardiac anomalies, single ventricle, procedure complexity, preoperative respiratory support, mechanical ventilation duration, and postoperative disease severity were associated with noninvasive ventilation therapy (p < 0.001 for all). Across hospitals, noninvasive ventilation use ranged from 32% to 65%, and adjusted mean noninvasive ventilation duration ranged from 1 to 4 days (3-d observed mean). Duration of total adjusted respiratory support was more strongly correlated with duration of mechanical ventilation compared with noninvasive

  11. Inhalation therapy in mechanical ventilation

    PubMed Central

    Maccari, Juçara Gasparetto; Teixeira, Cassiano; Gazzana, Marcelo Basso; Savi, Augusto; Dexheimer-Neto, Felippe Leopoldo; Knorst, Marli Maria

    2015-01-01

    Patients with obstructive lung disease often require ventilatory support via invasive or noninvasive mechanical ventilation, depending on the severity of the exacerbation. The use of inhaled bronchodilators can significantly reduce airway resistance, contributing to the improvement of respiratory mechanics and patient-ventilator synchrony. Although various studies have been published on this topic, little is known about the effectiveness of the bronchodilators routinely prescribed for patients on mechanical ventilation or about the deposition of those drugs throughout the lungs. The inhaled bronchodilators most commonly used in ICUs are beta adrenergic agonists and anticholinergics. Various factors might influence the effect of bronchodilators, including ventilation mode, position of the spacer in the circuit, tube size, formulation, drug dose, severity of the disease, and patient-ventilator synchrony. Knowledge of the pharmacological properties of bronchodilators and the appropriate techniques for their administration is fundamental to optimizing the treatment of these patients. PMID:26578139

  12. Ventilation of an hydrofoil wake

    NASA Astrophysics Data System (ADS)

    Arndt, Roger; Lee, Seung Jae; Monson, Garrett

    2013-11-01

    Ventilation physics plays a role in a variety of important engineering applications. For example, hydroturbine ventilation is used for control of vibration and cavitation erosion and more recently for improving the dissolved oxygen content of the flow through the turbine. The latter technology has been the focus of an ongoing study involving the ventilation of an hydrofoil wake to determine the velocity and size distribution of bubbles in a bubbly wake. This was carried out by utilizing particle shadow velocimetry (PSV). This technique is a non-scattering approach that relies on direct in-line volume illumination by a pulsed source such as a light-emitting diode (LED). The data are compared with previous studies of ventilated flow. The theoretical results of Hinze suggest that a scaling relationship is possible that can lead to developing appropriate design parameters for a ventilation system. Sponsored by ONR and DOE.

  13. A bench study of intensive-care-unit ventilators: new versus old and turbine-based versus compressed gas-based ventilators

    PubMed Central

    Thille, Arnaud W.; Lyazidi, Aissam; Richard, Jean-Christophe M.; Galia, Fabrice; Brochard, Laurent

    2009-01-01

    Objective To compare 13 commercially available, new-generation, intensive-care-unit (ICU) ventilators regarding trigger function, pressurization capacity during pressure-support ventilation (PSV), accuracy of pressure measurements and expiratory resistance. Design and Setting Bench study at a research laboratory in a university hospital. Material Four turbine-based ventilators and nine conventional servo-valve compressed-gas ventilators were tested using a two-compartment lung model. Results Three levels of effort were simulated. Each ventilator was evaluated at four PSV levels (5, 10, 15, and 20 cm H2O), with and without positive end-expiratory pressure (5 cm H2O, Trigger function was assessed as the time from effort onset to detectable pressurization. Pressurization capacity was evaluated using the airway pressure-time product computed as the net area under the pressure-time curve over the first 0.3 s after inspiratory effort onset. Expiratory resistance was evaluated by measuring trapped volume in controlled ventilation. Significant differences were found across the ventilators, with a range of triggering-delay from 42 ms to 88 ms for all conditions averaged (P<.001). Under difficult conditions, the triggering delay was longer than 100 ms and the pressurization was poor with five ventilators at PSV5 and three at PSV10, suggesting an inability to unload patient’s effort. On average, turbine-based ventilators performed better than conventional ventilators, which showed no improvement compared to a 2000 bench comparison. Conclusion Technical performances of trigger function, pressurization capacity and expiratory resistance vary considerably across new-generation ICU ventilators. ICU ventilators seem to have reached a technical ceiling in recent years, and some ventilators still perform inadequately. PMID:19352622

  14. A bench study of intensive-care-unit ventilators: new versus old and turbine-based versus compressed gas-based ventilators.

    PubMed

    Thille, Arnaud W; Lyazidi, Aissam; Richard, Jean-Christophe M; Galia, Fabrice; Brochard, Laurent

    2009-08-01

    To compare 13 commercially available, new-generation, intensive-care-unit (ICU) ventilators in terms of trigger function, pressurization capacity during pressure-support ventilation (PSV), accuracy of pressure measurements, and expiratory resistance. Bench study at a research laboratory in a university hospital. Four turbine-based ventilators and nine conventional servo-valve compressed-gas ventilators were tested using a two-compartment lung model. Three levels of effort were simulated. Each ventilator was evaluated at four PSV levels (5, 10, 15, and 20 cm H2O), with and without positive end-expiratory pressure (5 cm H2O). Trigger function was assessed as the time from effort onset to detectable pressurization. Pressurization capacity was evaluated using the airway pressure-time product computed as the net area under the pressure-time curve over the first 0.3 s after inspiratory effort onset. Expiratory resistance was evaluated by measuring trapped volume in controlled ventilation. Significant differences were found across the ventilators, with a range of triggering delays from 42 to 88 ms for all conditions averaged (P < 0.001). Under difficult conditions, the triggering delay was longer than 100 ms and the pressurization was poor for five ventilators at PSV5 and three at PSV10, suggesting an inability to unload patient's effort. On average, turbine-based ventilators performed better than conventional ventilators, which showed no improvement compared to a bench comparison in 2000. Technical performance of trigger function, pressurization capacity, and expiratory resistance differs considerably across new-generation ICU ventilators. ICU ventilators seem to have reached a technical ceiling in recent years, and some ventilators still perform inadequately.

  15. 6. VIEW LOOKING SOUTHEAST AT VENTILATION EQUIPMENT IN SOUTH VENTILATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. VIEW LOOKING SOUTHEAST AT VENTILATION EQUIPMENT IN SOUTH VENTILATION HOUSE. THIS AIR CONDITIONING SYSTEM WAS INSTALLED BY PARKS-CRAMER COMPANY OF FITCHBURG, MASSACHUSETTS WHEN THE MILL WAS CONSTRUCTED IN 1923-24. ONE AIR WASHER AND FAN ROOM EXTERIOR IS VISIBLE ON THE RIGHT. THE DUCTS FROM BOTH FAN ROOMS (CURVED METAL STRUCTURES AT CENTER AND LEFT OF PHOTO) ARE CONNECTED TO A COMMON AIR SHAFT. - Stark Mill, 117 Corinth Road, Hogansville, Troup County, GA

  16. Protective ventilation of preterm lambs exposed to acute chorioamnionitis does not reduce ventilation-induced lung or brain injury.

    PubMed

    Barton, Samantha K; Moss, Timothy J M; Hooper, Stuart B; Crossley, Kelly J; Gill, Andrew W; Kluckow, Martin; Zahra, Valerie; Wong, Flora Y; Pichler, Gerhard; Galinsky, Robert; Miller, Suzanne L; Tolcos, Mary; Polglase, Graeme R

    2014-01-01

    The onset of mechanical ventilation is a critical time for the initiation of cerebral white matter (WM) injury in preterm neonates, particularly if they are inadvertently exposed to high tidal volumes (VT) in the delivery room. Protective ventilation strategies at birth reduce ventilation-induced lung and brain inflammation and injury, however its efficacy in a compromised newborn is not known. Chorioamnionitis is a common antecedent of preterm birth, and increases the risk and severity of WM injury. We investigated the effects of high VT ventilation, after chorioamnionitis, on preterm lung and WM inflammation and injury, and whether a protective ventilation strategy could mitigate the response. Pregnant ewes (n = 18) received intra-amniotic lipopolysaccharide (LPS) 2 days before delivery, instrumentation and ventilation at 127±1 days gestation. Lambs were either immediately euthanased and used as unventilated controls (LPSUVC; n = 6), or were ventilated using an injurious high VT strategy (LPSINJ; n = 5) or a protective ventilation strategy (LPSPROT; n = 7) for a total of 90 min. Mean arterial pressure, heart rate and cerebral haemodynamics and oxygenation were measured continuously. Lungs and brains underwent molecular and histological assessment of inflammation and injury. LPSINJ lambs had poorer oxygenation than LPSPROT lambs. Ventilation requirements and cardiopulmonary and systemic haemodynamics were not different between ventilation strategies. Compared to unventilated lambs, LPSINJ and LPSPROT lambs had increases in pro-inflammatory cytokine expression within the lungs and brain, and increased astrogliosis (p<0.02) and cell death (p<0.05) in the WM, which were equivalent in magnitude between groups. Ventilation after acute chorioamnionitis, irrespective of strategy used, increases haemodynamic instability and lung and cerebral inflammation and injury. Mechanical ventilation is a potential contributor to WM injury in infants exposed to

  17. 46 CFR 153.312 - Ventilation system standards.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Handling Space Ventilation § 153.312 Ventilation system standards. A cargo handling space ventilation... (approx. 32.8 ft) from openings into or ventilation intakes for, accommodation or service spaces. (b) A...

  18. 46 CFR 153.312 - Ventilation system standards.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Handling Space Ventilation § 153.312 Ventilation system standards. A cargo handling space ventilation... (approx. 32.8 ft) from openings into or ventilation intakes for, accommodation or service spaces. (b) A...

  19. 46 CFR 153.312 - Ventilation system standards.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Handling Space Ventilation § 153.312 Ventilation system standards. A cargo handling space ventilation... (approx. 32.8 ft) from openings into or ventilation intakes for, accommodation or service spaces. (b) A...

  20. 46 CFR 153.312 - Ventilation system standards.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Handling Space Ventilation § 153.312 Ventilation system standards. A cargo handling space ventilation... (approx. 32.8 ft) from openings into or ventilation intakes for, accommodation or service spaces. (b) A...

  1. 46 CFR 153.312 - Ventilation system standards.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Handling Space Ventilation § 153.312 Ventilation system standards. A cargo handling space ventilation... (approx. 32.8 ft) from openings into or ventilation intakes for, accommodation or service spaces. (b) A...

  2. A regulator for pressure-controlled total-liquid ventilation.

    PubMed

    Robert, Raymond; Micheau, Philippe; Avoine, Olivier; Beaudry, Benoit; Beaulieu, Alexandre; Walti, Hervé

    2010-09-01

    Total-liquid ventilation (TLV) is an innovative experimental method of mechanical-assisted ventilation in which lungs are totally filled and then ventilated with a tidal volume of perfluorochemical liquid by using a dedicated liquid ventilator. Such a novel medical device must resemble other conventional ventilators: it must be able to conduct controlled-pressure ventilation. The objective was to design a robust controller to perform pressure-regulated expiratory flow and to implement it on our latest liquid-ventilator prototype (Inolivent-4). Numerical simulations, in vitro experiments, and in vivo experiments in five healthy term newborn lambs have demonstrated that it was efficient to generate expiratory flows while avoiding collapses. Moreover, the in vivo results have demonstrated that our liquid ventilator can maintain adequate gas exchange, normal acid-base equilibrium, and achieve greater minute ventilation, better oxygenation and CO2 extraction, while nearing flow limits. Hence, it is our suggestion to perform pressure-controlled ventilation during expiration with minute ventilation equal or superior to 140 mL x min(-1) x kg(-1) in order to ensure PaCO2 below 55 mmHg. From a clinician's point of view, pressure-controlled ventilation greatly simplifies the use of the liquid ventilator, which will certainly facilitate its introduction in intensive care units for clinical applications.

  3. Hospitalizations in patients with atrial fibrillation: an analysis from ROCKET AF.

    PubMed

    DeVore, Adam D; Hellkamp, Anne S; Becker, Richard C; Berkowitz, Scott D; Breithardt, Guenter; Hacke, Werner; Halperin, Jonathan L; Hankey, Graeme J; Mahaffey, Kenneth W; Nessel, Christopher C; Singer, Daniel E; Fox, Keith A A; Patel, Manesh R; Piccini, Jonathan P

    2016-08-01

    The high costs associated with treatment for atrial fibrillation (AF) are primarily due to hospital care, but there are limited data to understand the reasons for and predictors of hospitalization in patients with AF. The ROCKET AF trial compared rivaroxaban with warfarin for stroke prophylaxis in AF. We described the frequency of and reasons for hospitalization during study follow-up and utilized Cox proportional hazards models to assess for baseline characteristics associated with all-cause hospitalization. Of 14 171 patients, 14% were hospitalized at least once. Of 2614 total hospitalizations, 41% were cardiovascular including 4% for AF; of the remaining, 12% were for bleeding. Compared with patients not hospitalized, hospitalized patients were older (74 vs. 72 years), and more frequently had diabetes (46 vs. 39%), prior MI (23 vs. 16%), and paroxysmal AF (19 vs. 17%), but less frequently had prior transient ischaemic attack/stroke (49 vs. 56%). After multivariable adjustment, lung disease [hazard ratio (HR) 1.46, 95% confidence interval (CI) 1.29-1.66], diabetes [1.22, (1.11-1.34)], prior MI [1.27, (1.13-1.42)], and renal dysfunction [HR 1.07 per 5 unit GFR < 65 mL/min, (1.04-1.10)] were associated with increased hospitalization risk. Treatment assignment was not associated with differential rates of hospitalization. Nearly 1 in 7 of the moderate-to-high-risk patients with AF enrolled in this trial was hospitalized within 2 years, and both AF and bleeding were rare causes of hospitalization. Further research is needed to determine whether care pathways directed at comorbid conditions among AF patients could reduce the need for and costs associated with hospitalization. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Cardiology.

  4. Adiabatic Compression Sensitivity of AF-M315E (Briefing Charts)

    DTIC Science & Technology

    2015-07-27

    Charts 3. DATES COVERED (From - To) July 2015-July 2015 4. TITLE AND SUBTITLE Adiabatic Compression Sensitivity of AF - M315E (Briefing Charts) 5a...PA#15402. 14. ABSTRACT The Air Force Research Laboratory developed monopropellant, AF - M315E , has been selected for demonstration under the NASA...Pollux Drive, Edwards AFB, CA 93524-7048. Adiabatic Compression Sensitivity of AF - M315E Phu Quach ERC, Incorporated Air Force Research Laboratory

  5. 33 CFR 183.620 - Natural ventilation system.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Natural ventilation system. 183... (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Ventilation § 183.620 Natural ventilation system. (a) Except for compartments open to the atmosphere, a natural ventilation system that meets the...

  6. 33 CFR 183.620 - Natural ventilation system.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Natural ventilation system. 183... (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Ventilation § 183.620 Natural ventilation system. (a) Except for compartments open to the atmosphere, a natural ventilation system that meets the...

  7. Intraoperative mechanical ventilation for the pediatric patient.

    PubMed

    Kneyber, Martin C J

    2015-09-01

    Invasive mechanical ventilation is required when children undergo general anesthesia for any procedure. It is remarkable that one of the most practiced interventions such as pediatric mechanical ventilation is hardly supported by any scientific evidence but rather based on personal experience and data from adults, especially as ventilation itself is increasingly recognized as a harmful intervention that causes ventilator-induced lung injury. The use of low tidal volume and higher levels of positive end-expiratory pressure became an integral part of lung-protective ventilation following the outcomes of clinical trials in critically ill adults. This approach has been readily adopted in pediatric ventilation. However, a clear association between tidal volume and mortality has not been ascertained in pediatrics. In fact, experimental studies have suggested that young children might be less susceptible to ventilator-induced lung injury. As such, no recommendations on optimal lung-protective ventilation strategy in children with or without lung injury can be made. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Recommendations for mechanical ventilation of critically ill children from the Paediatric Mechanical Ventilation Consensus Conference (PEMVECC).

    PubMed

    Kneyber, Martin C J; de Luca, Daniele; Calderini, Edoardo; Jarreau, Pierre-Henri; Javouhey, Etienne; Lopez-Herce, Jesus; Hammer, Jürg; Macrae, Duncan; Markhorst, Dick G; Medina, Alberto; Pons-Odena, Marti; Racca, Fabrizio; Wolf, Gerhard; Biban, Paolo; Brierley, Joe; Rimensberger, Peter C

    2017-12-01

    Much of the common practice in paediatric mechanical ventilation is based on personal experiences and what paediatric critical care practitioners have adopted from adult and neonatal experience. This presents a barrier to planning and interpretation of clinical trials on the use of specific and targeted interventions. We aim to establish a European consensus guideline on mechanical ventilation of critically children. The European Society for Paediatric and Neonatal Intensive Care initiated a consensus conference of international European experts in paediatric mechanical ventilation to provide recommendations using the Research and Development/University of California, Los Angeles, appropriateness method. An electronic literature search in PubMed and EMBASE was performed using a combination of medical subject heading terms and text words related to mechanical ventilation and disease-specific terms. The Paediatric Mechanical Ventilation Consensus Conference (PEMVECC) consisted of a panel of 15 experts who developed and voted on 152 recommendations related to the following topics: (1) general recommendations, (2) monitoring, (3) targets of oxygenation and ventilation, (4) supportive measures, (5) weaning and extubation readiness, (6) normal lungs, (7) obstructive diseases, (8) restrictive diseases, (9) mixed diseases, (10) chronically ventilated patients, (11) cardiac patients and (12) lung hypoplasia syndromes. There were 142 (93.4%) recommendations with "strong agreement". The final iteration of the recommendations had none with equipoise or disagreement. These recommendations should help to harmonise the approach to paediatric mechanical ventilation and can be proposed as a standard-of-care applicable in daily clinical practice and clinical research.

  9. 46 CFR 194.20-5 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS HANDLING, USE, AND... Ventilation. (a) Chemical storerooms shall be equipped with a power ventilation system of exhaust type. The... based upon the volume of the compartment. (1) Power ventilation units shall have nonsparking impellers...

  10. [Ventilator associated pneumonia].

    PubMed

    Bellani, S; Nesci, M; Celotto, S; Lampati, L; Lucchini, A

    2003-04-01

    Ventilator associated pneumonia (VAP) is a nosocomial lower respiratory tract infection that ensues in critically ill patients undergoing mechanical ventilation. The reported incidence of VAP varies between 9% and 68% with a mortality ranging between 33% and 71%. Two key factors are implicated in the pathogenesis of VAP: bacterial colonization of the upper digestive-respiratory tract and aspiration of oral secretions into the trachea. Preventive measurements are advocated to reduce the incidence of VAP, such as selective decontamination of the digestive tract (SDD), supraglottic aspiration and positioning. Prompt recognition and treatment of established VAP has also been demostrated to affect outcome. Therefore, the knowledge of risk factors associated with the development of VAP and the implementation of strategies to prevent, diagnose and treat VAP are mainstems in the nursing of mechanically ventilated patients.

  11. Using domiciliary non-invasive ventilator data downloads to inform clinical decision-making to optimise ventilation delivery and patient compliance

    PubMed Central

    Mansell, Stephanie K; Cutts, Steven; Hackney, Isobel; Wood, Martin J; Hawksworth, Kevin; Creer, Dean D; Kilbride, Cherry; Mandal, Swapna

    2018-01-01

    Introduction Ventilation parameter data from patients receiving home mechanical ventilation can be collected via secure data cards and modem technology. This can then be reviewed by clinicians and ventilator prescriptions adjusted. Typically available measures include tidal volume (VT), leak, respiratory rate, minute ventilation, patient triggered breaths, achieved pressures and patient compliance. This study aimed to assess the potential impact of ventilator data downloads on management of patients requiring home non-invasive ventilation (NIV). Methods A longitudinal within-group design with repeated measurements was used. Baseline ventilator data were downloaded, reviewed and adjustments made to optimise ventilation. Leak, VT and compliance data were collected for comparison at the first review and 3–7 weeks later. Ventilator data were monitored and amended remotely via a modem by a consultant physiotherapist between the first review and second appointment. Results Analysis of data from 52 patients showed increased patient compliance (% days used >4 hours) from 90% to 96% (p=0.007), increased usage from 6.53 to 6.94 hours (p=0.211) and a change in VT(9.4 vs 8.7 mL/kg/ideal body weight, p=0.022). There was no change in leak following review of NIV prescriptions (mean (SD): 43 (23.4) L/min vs 45 (19.9)L/min, p=0.272). Conclusion Ventilator data downloads, via early remote assessment, can help optimise patient ventilation through identification of modifiable factors, in particular interface leak and ventilator prescriptions. However, a prospective study is required to assess whether using ventilator data downloads provides value in terms of patient outcomes and cost-effectiveness. The presented data will help to inform the design of such a study. PMID:29531743

  12. AF RPA Training: Utility and Tradition in Conflict

    DTIC Science & Technology

    2017-06-01

    The AF and the Army offer competing views on the future of UAS training . Both services export its cultural values, as the Navy, USMC, and...and visions. Despite common technologies, each service approached UAS from different starting points, and created different training models. The AF...issues reflected different approaches each service took to Unmanned Aerial Systems (UAS) operational employment, personnel management, and training

  13. Experimental study of airflow characteristics of stratum ventilation in a multi-occupant room with comparison to mixing ventilation and displacement ventilation.

    PubMed

    Cheng, Y; Lin, Z

    2015-12-01

    The motivation of this study is stimulated by a lack of knowledge about the difference of airflow characteristics between a novel air distribution method [i.e., stratum ventilation (SV)] and conventional air distribution methods [i.e., mixing ventilation (MV) and displacement ventilation (DV)]. Detailed air velocity and temperature measurements were conducted in the occupied zone of a classroom with dimensions of 8.8 m (L) × 6.1 m (W) × 2.4 m (H). Turbulence intensity and power spectrum of velocity fluctuation were calculated using the measured data. Thermal comfort and cooling efficiency were also compared. The results show that in the occupied zone, the airflow characteristics among MV, DV, and SV are different. The turbulent airflow fluctuation is enhanced in this classroom with multiple thermal manikins due to thermal buoyancy and airflow mixing effect. Thermal comfort evaluations indicate that in comparison with MV and DV, a higher supply air temperature should be adopted for SV to achieve general thermal comfort with low draft risk. Comparison of the mean air temperatures in the occupied zone reveals that SV is of highest cooling efficiency, followed by DV and then MV. This study reports the unique profiles of flow, temperature, turbulence intensity, and power spectrum of stratum ventilation, which can have a number of implications for both knowledge and understanding of the flow characteristics in a stratum-ventilated room. With respect to the former, it expounds the fundamental characteristics of this air distribution method; and with respect to the latter, it reveals the mechanism of thermal comfort and energy saving under stratum ventilation. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Performance of ICU ventilators during noninvasive ventilation with large leaks in a total face mask: a bench study.

    PubMed

    Nakamura, Maria Aparecida Miyuki; Costa, Eduardo Leite Vieira; Carvalho, Carlos Roberto Ribeiro; Tucci, Mauro Roberto

    2014-01-01

    Discomfort and noncompliance with noninvasive ventilation (NIV) interfaces are obstacles to NIV success. Total face masks (TFMs) are considered to be a very comfortable NIV interface. However, due to their large internal volume and consequent increased CO2 rebreathing, their orifices allow proximal leaks to enhance CO2 elimination. The ventilators used in the ICU might not adequately compensate for such leakage. In this study, we attempted to determine whether ICU ventilators in NIV mode are suitable for use with a leaky TFM. This was a bench study carried out in a university research laboratory. Eight ICU ventilators equipped with NIV mode and one NIV ventilator were connected to a TFM with major leaks. All were tested at two positive end-expiratory pressure (PEEP) levels and three pressure support levels. The variables analyzed were ventilation trigger, cycling off, total leak, and pressurization. Of the eight ICU ventilators tested, four did not work (autotriggering or inappropriate turning off due to misdetection of disconnection); three worked with some problems (low PEEP or high cycling delay); and one worked properly. The majority of the ICU ventilators tested were not suitable for NIV with a leaky TFM.

  15. Performance of ICU ventilators during noninvasive ventilation with large leaks in a total face mask: a bench study* **

    PubMed Central

    Nakamura, Maria Aparecida Miyuki; Costa, Eduardo Leite Vieira; Carvalho, Carlos Roberto Ribeiro; Tucci, Mauro Roberto

    2014-01-01

    Objective: Discomfort and noncompliance with noninvasive ventilation (NIV) interfaces are obstacles to NIV success. Total face masks (TFMs) are considered to be a very comfortable NIV interface. However, due to their large internal volume and consequent increased CO2 rebreathing, their orifices allow proximal leaks to enhance CO2 elimination. The ventilators used in the ICU might not adequately compensate for such leakage. In this study, we attempted to determine whether ICU ventilators in NIV mode are suitable for use with a leaky TFM. Methods: This was a bench study carried out in a university research laboratory. Eight ICU ventilators equipped with NIV mode and one NIV ventilator were connected to a TFM with major leaks. All were tested at two positive end-expiratory pressure (PEEP) levels and three pressure support levels. The variables analyzed were ventilation trigger, cycling off, total leak, and pressurization. Results: Of the eight ICU ventilators tested, four did not work (autotriggering or inappropriate turning off due to misdetection of disconnection); three worked with some problems (low PEEP or high cycling delay); and one worked properly. Conclusions: The majority of the ICU ventilators tested were not suitable for NIV with a leaky TFM. PMID:25029653

  16. 46 CFR 111.15-10 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-10 Ventilation. (a) General. Each room, locker, and box for storage batteries must be arranged or ventilated to prevent... with the battery charger so that the battery cannot be charged without ventilation. (c) Large battery...

  17. 46 CFR 111.15-10 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-10 Ventilation. (a) General. Each room, locker, and box for storage batteries must be arranged or ventilated to prevent... with the battery charger so that the battery cannot be charged without ventilation. (c) Large battery...

  18. 46 CFR 111.15-10 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-10 Ventilation. (a) General. Each room, locker, and box for storage batteries must be arranged or ventilated to prevent... with the battery charger so that the battery cannot be charged without ventilation. (c) Large battery...

  19. 46 CFR 111.15-10 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-10 Ventilation. (a) General. Each room, locker, and box for storage batteries must be arranged or ventilated to prevent... with the battery charger so that the battery cannot be charged without ventilation. (c) Large battery...

  20. 46 CFR 111.15-10 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-10 Ventilation. (a) General. Each room, locker, and box for storage batteries must be arranged or ventilated to prevent... with the battery charger so that the battery cannot be charged without ventilation. (c) Large battery...

  1. Space station ventilation study

    NASA Technical Reports Server (NTRS)

    Colombo, G. V.; Allen, G. E.

    1972-01-01

    A ventilation system design and selection method which is applicable to any manned vehicle were developed. The method was used to generate design options for the NASA 33-foot diameter space station, all of which meet the ventilation system design requirements. System characteristics such as weight, volume, and power were normalized to dollar costs for each option. Total system costs for the various options ranged from a worst case $8 million to a group of four which were all approximately $2 million. A system design was then chosen from the $2 million group and is presented in detail. A ventilation system layout was designed for the MSFC space station mockup which provided comfortable, efficient ventilation of the mockup. A conditioned air distribution system design for the 14-foot diameter modular space station, using the same techniques, is also presented. The tradeoff study resulted in the selection of a system which costs $1.9 million, as compared to the alternate configuration which would have cost $2.6 million.

  2. A new system for understanding modes of mechanical ventilation.

    PubMed

    Chatburn, R L; Primiano, F P

    2001-06-01

    Numerous ventilation modes and ventilation options have become available as new mechanical ventilators have reached the market. Ventilator manufacturers have no standardized terminology for ventilator modes and ventilation options, and ventilator operator's manuals do not help the clinician compare the modes of ventilators from different manufacturers. This article proposes a standardized system for classifying ventilation modes, based on general engineering principles and a small set of explicit definitions. Though there may be resistance by ventilator manufacturers to a standardized system of ventilation terminology, clinicians and health care equipment purchasers should adopt such a system in the interest of clear communication--the lack of which prevents clinicians from fully understanding the therapies they administer and could compromise the quality of patient care.

  3. A randomised crossover comparison of mouth-to-face-shield ventilation and mouth-to-pocket-mask ventilation by surf lifeguards in a manikin.

    PubMed

    Adelborg, K; Bjørnshave, K; Mortensen, M B; Espeseth, E; Wolff, A; Løfgren, B

    2014-07-01

    Thirty surf lifeguards (mean (SD) age: 25.1 (4.8) years; 21 male, 9 female) were randomly assigned to perform 2 × 3 min of cardiopulmonary resuscitation on a manikin using mouth-to-face-shield ventilation (AMBU LifeKey) and mouth-to-pocket-mask ventilation (Laerdal Pocket Mask). Interruptions in chest compressions, effective ventilation (visible chest rise) ratio, tidal volume and inspiratory time were recorded. Interruptions in chest compressions per cycle were increased with mouth-to-face-shield ventilation (mean (SD) 8.6 (1.7) s) compared with mouth-to-pocket-mask ventilation (6.9 (1.2) s, p < 0.0001). The proportion of effective ventilations was less using mouth-to-face-shield ventilation (199/242 (82%)) compared with mouth-to-pocket-mask ventilation (239/240 (100%), p = 0.0002). Tidal volume was lower using mouth-to-face-shield ventilation (mean (SD) 0.36 (0.20) l) compared with mouth-to-pocket-mask ventilation (0.45 (0.20) l, p = 0.006). No differences in inspiratory times were observed between mouth-to-face-shield ventilation and mouth-to-pocket-mask ventilation. In conclusion, mouth-to-face-shield ventilation increases interruptions in chest compressions, reduces the proportion of effective ventilations and decreases delivered tidal volumes compared with mouth-to-pocket-mask ventilation. © 2014 The Association of Anaesthetists of Great Britain and Ireland.

  4. Monitoring of noninvasive ventilation by built-in software of home bilevel ventilators: a bench study.

    PubMed

    Contal, Olivier; Vignaux, Laurence; Combescure, Christophe; Pepin, Jean-Louis; Jolliet, Philippe; Janssens, Jean-Paul

    2012-02-01

    Current bilevel positive-pressure ventilators for home noninvasive ventilation (NIV) provide physicians with software that records items important for patient monitoring, such as compliance, tidal volume (Vt), and leaks. However, to our knowledge, the validity of this information has not yet been independently assessed. Testing was done for seven home ventilators on a bench model adapted to simulate NIV and generate unintentional leaks (ie, other than of the mask exhalation valve). Five levels of leaks were simulated using a computer-driven solenoid valve (0-60 L/min) at different levels of inspiratory pressure (15 and 25 cm H(2)O) and at a fixed expiratory pressure (5 cm H(2)O), for a total of 10 conditions. Bench data were compared with results retrieved from ventilator software for leaks and Vt. For assessing leaks, three of the devices tested were highly reliable, with a small bias (0.3-0.9 L/min), narrow limits of agreement (LA), and high correlations (R(2), 0.993-0.997) when comparing ventilator software and bench results; conversely, for four ventilators, bias ranged from -6.0 L/min to -25.9 L/min, exceeding -10 L/min for two devices, with wide LA and lower correlations (R(2), 0.70-0.98). Bias for leaks increased markedly with the importance of leaks in three devices. Vt was underestimated by all devices, and bias (range, 66-236 mL) increased with higher insufflation pressures. Only two devices had a bias < 100 mL, with all testing conditions considered. Physicians monitoring patients who use home ventilation must be aware of differences in the estimation of leaks and Vt by ventilator software. Also, leaks are reported in different ways according to the device used.

  5. Mechanical Ventilation and Bronchopulmonary Dysplasia.

    PubMed

    Keszler, Martin; Sant'Anna, Guilherme

    2015-12-01

    Mechanical ventilation is an important potentially modifiable risk factor for the development of bronchopulmonary dysplasia. Effective use of noninvasive respiratory support reduces the risk of lung injury. Lung volume recruitment and avoidance of excessive tidal volume are key elements of lung-protective ventilation strategies. Avoidance of oxidative stress, less invasive methods of surfactant administration, and high-frequency ventilation are also important factors in lung injury prevention. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Contaminants in ventilated filling boxes

    NASA Astrophysics Data System (ADS)

    Bolster, D. T.; Linden, P. F.

    While energy efficiency is important, the adoption of energy-efficient ventilation systems still requires the provision of acceptable indoor air quality. Many low-energy systems, such as displacement or natural ventilation, rely on temperature stratification within the interior environment, always extracting the warmest air from the top of the room. Understanding buoyancy-driven convection in a confined ventilated space is key to understanding the flow that develops with many of these modern low-energy ventilation schemes. In this work we study the transport of an initially uniformly distributed passive contaminant in a displacement-ventilated space. Representing a heat source as an ideal sourced of buoyancy, analytical and numerical models are developed that allow us to compare the average efficiency of contaminant removal between traditional mixing and modern low-energy systems. A set of small-scale analogue laboratory experiments was also conducted to further validate our analytical and numerical solutions.We find that on average traditional and low-energy ventilation methods are similar with regard to pollutant flushing efficiency. This is because the concentration being extracted from the system at any given time is approximately the same for both systems. However, very different vertical concentration gradients exist. For the low-energy system, a peak in contaminant concentration occurs at the temperature interface that is established within the space. This interface is typically designed to sit at some intermediate height in the space. Since this peak does not coincide with the extraction point, displacement ventilation does not offer the same benefits for pollutant flushing as it does for buoyancy removal.

  7. Ventilation of carbon monoxide from a biomass pellet storage tank--a study of the effects of variation of temperature and cross-ventilation on the efficiency of natural ventilation.

    PubMed

    Emhofer, Waltraud; Lichtenegger, Klaus; Haslinger, Walter; Hofbauer, Hermann; Schmutzer-Roseneder, Irene; Aigenbauer, Stefan; Lienhard, Martin

    2015-01-01

    Wood pellets have been reported to emit toxic gaseous emissions during transport and storage. Carbon monoxide (CO) emission, due to the high toxicity of the gas and the possibility of it being present at high levels, is the most imminent threat to be considered before entering a pellet storage facility. For small-scale (<30 tons storage capacity) residential pellet storage facilities, ventilation, preferably natural ventilation utilizing already existing openings, has become the most favored solution to overcome the problem of high CO concentrations. However, there is little knowledge on the ventilation rates that can be reached and thus on the effectiveness of such measures. The aim of the study was to investigate ventilation rates for a specific small-scale pellet storage system depending on characteristic temperature differences. Furthermore, the influence of the implementation of a chimney and the influence of cross-ventilation on the ventilation rates were investigated. The air exchange rates observed in the experiments ranged between close to zero and up to 8 m(3) h(-1), depending largely on the existing temperature differences and the existence of cross-ventilation. The results demonstrate that implementing natural ventilation is a possible measure to enhance safety from CO emissions, but not one without limitations. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  8. Mechanical ventilation strategies.

    PubMed

    Keszler, Martin

    2017-08-01

    Although only a small proportion of full term and late preterm infants require invasive respiratory support, they are not immune from ventilator-associated lung injury. The process of lung damage from mechanical ventilation is multifactorial and cannot be linked to any single variable. Atelectrauma and volutrauma have been identified as the most important and potentially preventable elements of lung injury. Respiratory support strategies for full term and late preterm infants have not been as thoroughly studied as those for preterm infants; consequently, a strong evidence base on which to make recommendations is lacking. The choice of modalities of support and ventilation strategies should be guided by the specific underlying pathophysiologic considerations and the ventilatory approach must be individualized for each patient based on the predominant pathophysiology at the time. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Dental Laboratory Career Ladder AFS 982X0.

    DTIC Science & Technology

    1982-09-01

    7ADA120 102 AIR FORCE OCCUPATIONAL MEASUREMENT CENTER RANDOLPH AFB TX F/6 Ri9 DENTAL LABORATORY CAREER LADDER AFS 982XO.(U) UNCLASSIFIED NLEEEili E...Eli E~lllllllllEEE EEEEEIIIEEEEEE EIEEEEIIEEEEEE IIIIIIIIIIIIIIlLZ UNITED STATES AIR FORCE 0! DENTAL LABORATORY CAREER LADDER DTlC AFS 982X0 ELEr.L_...LADDER STRUCTURE GROUPS ----------------------------------- 57 APPENDIX B - JOB DESCRIPTIONS FOR BASE AND AREA DENTAL LABORATORY PERSONNEL

  10. Refinement of detecting atrial fibrillation in stroke patients: results from the TRACK-AF Study.

    PubMed

    Reinke, F; Bettin, M; Ross, L S; Kochhäuser, S; Kleffner, I; Ritter, M; Minnerup, J; Dechering, D; Eckardt, L; Dittrich, R

    2018-04-01

    Detection of occult atrial fibrillation (AF) is crucial for optimal secondary prevention in stroke patients. The AF detection rate was determined by implantable cardiac monitor (ICM) and compared to the prediction rate of the probability of incident AF by software based analysis of a continuously monitored electrocardiogram at follow-up (stroke risk analysis, SRA); an optimized AF detection algorithm is proposed by combining both tools. In a monocentric prospective study 105 out of 389 patients with cryptogenic stroke despite extensive diagnostic workup were investigated with two additional cardiac monitoring tools: (a) 20 months' monitoring by ICM and (b) SRA during hospitalization at the stroke unit. The detection rate of occult AF was 18% by ICM (n = 19) (range 6-575 days) and 62% (n = 65) had an increased risk for AF predicted by SRA. When comparing the predictive accuracy of SRA to ICM, the sensitivity was 95%, specificity 35%, positive predictive value 27% and negative predictive value 96%. In 18 patients with AF detected by ICM, SRA also showed a medium risk for AF. Only one patient with a very low risk predicted by SRA developed AF revealed by ICM after 417 days. A combination of SRA and ICM is a promising strategy to detect occult AF. SRA is reliable in predicting incident AF with a high negative predictive value. Thus, SRA may serve as a cost-effective pre-selection tool identifying patients at risk for AF who may benefit from further cardiac monitoring by ICM. © 2017 EAN.

  11. Circuit compliance compensation in lung protective ventilation.

    PubMed

    Masselli, Grazia Maria Pia; Silvestri, Sergio; Sciuto, Salvatore Andrea; Cappa, Paolo

    2006-01-01

    Lung protective ventilation utilizes low tidal volumes to ventilate patients with severe lung pathologies. The compensation of breathing circuit effects, i.e. those induced by compressible volume of the circuit, results particularly critical in the calculation of the actual tidal volume delivered to patient's respiratory system which in turns is responsible of the level of permissive hypercapnia. The present work analyzes the applicability of the equation for circuit compressible volume compensation in the case of pressure and volume controlled lung protective ventilation. Experimental tests conducted in-vitro show that the actual tidal volume can be reliably estimated if the compliance of the breathing circuit is measured with the same parameters and ventilation technique that will be utilized in lung protective ventilation. Differences between volume and pressure controlled ventilation are also quantitatively assessed showing that pressure controlled ventilation allows a more reliable compensation of breathing circuit compressible volume.

  12. Inadequate face mask ventilation--clinical applications.

    PubMed

    Goranović, Tatjana; Milić, Morena; Holjevac, Jadranka Katancić; Maldini, Branka; Sakić, Katarina

    2010-09-01

    Face mask ventilation is a life saving technique. This article will review aetiology and patophysiological consequences of inadequate mask ventilation. The main focus will be on circulatory changes during induction of anesthesia, before and in a short period after intubation that could be attributed to inadequate mask ventilation in humans.

  13. Low Tidal Volume Ventilation in Patients without Acute Respiratory Distress Syndrome: A Paradigm Shift in Mechanical Ventilation

    PubMed Central

    Lipes, Jed; Bojmehrani, Azadeh; Lellouche, Francois

    2012-01-01

    Protective ventilation with low tidal volume has been shown to reduce morbidity and mortality in patients suffering from acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). Low tidal volume ventilation is associated with particular clinical challenges and is therefore often underutilized as a therapeutic option in clinical practice. Despite some potential difficulties, data have been published examining the application of protective ventilation in patients without lung injury. We will briefly review the physiologic rationale for low tidal volume ventilation and explore the current evidence for protective ventilation in patients without lung injury. In addition, we will explore some of the potential reasons for its underuse and provide strategies to overcome some of the associated clinical challenges. PMID:22536499

  14. 32 CFR 989.12 - AF Form 813, Request for Environmental Impact Analysis.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false AF Form 813, Request for Environmental Impact... FORCE ENVIRONMENTAL PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.12 AF Form 813, Request for Environmental Impact Analysis. The Air Force uses AF Form 813 to document the need for...

  15. Infiltration as Ventilation: Weather-Induced Dilution

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

    Sherman, Max H.; Turner, William J.N.; Walker, Iain S.

    The purpose of outdoor air ventilation is to dilute or remove indoor contaminants to which occupants are exposed. It can be provided by mechanical or natural means. In most homes, especially older homes, weather-driven infiltration provides the dominant fraction of the total ventilation. As we seek to provide good indoor air quality at minimum energy cost, it is important to neither over-ventilate nor under-ventilate. Thus, it becomes critically important to evaluate correctly the contribution infiltration makes to the total outdoor air ventilation rate. Because weather-driven infiltration is dependent on building air leakage and weather-induced pressure differences, a given amount ofmore » air leakage will provide different amounts of infiltration. Varying rates of infiltration will provide different levels of contaminant dilution and hence effective ventilation. This paper derives these interactions and then calculates the impact of weather-driven infiltration for different climates. A new “N-factor” is introduced to provide a convenient method for calculating the ventilation contribution of infiltration for over 1,000 locations across North America. The results of this work could be used in indoor air quality standards (specifically ASHRAE 62.2) to account for the contribution of weather-driven infiltration towards the dilution of indoor pollutants.« less

  16. Antibiotic therapy in ventilator-associated tracheobronchitis: a literature review.

    PubMed

    Alves, Abel Eduardo; Pereira, José Manuel

    2018-03-01

    The concept of ventilator-associated tracheobronchitis is controversial; its definition is not unanimously accepted and often overlaps with ventilator-associated pneumonia. Ventilator-associated tracheobronchitis has an incidence similar to that of ventilator-associated pneumonia, with a high prevalence of isolated multiresistant agents, resulting in an increase in the time of mechanical ventilation and hospitalization but without an impact on mortality. The performance of quantitative cultures may allow better diagnostic definition of tracheobronchitis associated with mechanical ventilation, possibly avoiding the overdiagnosis of this condition. One of the major difficulties in differentiating between ventilator-associated tracheobronchitis and ventilator-associated pneumonia is the exclusion of a pulmonary infiltrate by chest radiography; thoracic computed tomography, thoracic ultrasonography, or invasive specimen collection may also be required. The institution of systemic antibiotic therapy does not improve the clinical impact of ventilator-associated tracheobronchitis, particularly in reducing time of mechanical ventilation, hospitalization or mortality, despite the possible reduced progression to ventilator-associated pneumonia. However, there are doubts regarding the methodology used. Thus, considering the high prevalence of tracheobronchitis associated with mechanical ventilation, routine treatment of this condition would result in high antibiotic usage without clear benefits. However, we suggest the institution of antibiotic therapy in patients with tracheobronchitis associated with mechanical ventilation and septic shock and/or worsening of oxygenation, and other auxiliary diagnostic tests should be simultaneously performed to exclude ventilator-associated pneumonia. This review provides a better understanding of the differentiation between tracheobronchitis associated with mechanical ventilation and pneumonia associated with mechanical ventilation, which

  17. Effects of Iron Depletion on CALM-AF10 Leukemias

    PubMed Central

    Heath, Jessica L.; Weiss, Joshua M.

    2014-01-01

    Iron, an essential nutrient for cellular growth and proliferation, enters cells via clathrin-mediated endocytosis (CME). The clathrin assembly lymphoid myeloid (CALM) protein plays an essential role in the cellular import of iron by CME. CALM-AF10 leukemias harbor a single copy of the normal CALM gene, and may therefore be more sensitive to the growth inhibitory effect of iron restriction compared with normal hematopoietic cells. We found that Calm heterozygous (CalmHET) murine fibroblasts exhibit signs of iron deficiency, with increased surface transferrin receptor (sTfR) levels and reduced growth rates. CalmHET hematopoietic cells are more sensitive in vitro to iron chelators than their wild type counterparts. Iron chelation also displayed toxicity towards cultured CalmHET CALM-AF10 leukemia cells and this effect was additive to that of chemotherapy. In mice transplanted with CalmHET CALM-AF10 leukemia, we found that dietary iron restriction reduces tumor burden in the spleen. However, dietary iron restriction, used alone or in conjunction with chemotherapy, did not increase survival of mice with CalmHET CALM-AF10 leukemia. In summary, while Calm heterozygosity results in iron deficiency and increased sensitivity to iron chelation in vitro, our data in mice do not suggest that iron depletion strategies would be beneficial for the therapy of CALM-AF10 leukemia patients. PMID:25193880

  18. Termination of persistent atrial fibrillation during pulmonary vein isolation: insight from the MAGIC-AF trial.

    PubMed

    Singh, Sheldon M; d'Avila, Andre; Kim, Young-Hoon; Aryana, Arash; Mangrum, J Michael; Michaud, Gregory F; Dukkipati, Srinivas R; Barrett, Conor D; Heist, E Kevin; Parides, Michael K; Thorpe, Kevin E; Reddy, Vivek Y

    2017-10-01

    Controversy on the optimal ablation strategy for persistent atrial fibrillation (AF) exists with limited work evaluating a strategy of pulmonary vein isolation (PVI) alone when AF terminates during PVI. Thirty-five patients had AF termination during PVI in the Modified Ablation Guided by Ibutilide Use in Chronic Atrial Fibrillation (MAGIC-AF; ClinicalTrials.gov number: NCT01014741) study. The objective of the current study is to report the 1-year outcome after PVI alone in this unique patient group. The 1-year single procedure freedom from atrial arrhythmia off anti-arrhythmic drugs was reported for the 35 patients in the MAGIC-AF study with persistent AF termination during or upon completion of PVI. Freedom from recurrent atrial arrhythmia was achieved in 60% of patients where AF terminated during PVI. Cavotricuspid isthmus flutter was common when AF terminated to a macro re-entrant flutter during PVI, and responsible for 92% of all flutter circuits with AF termination. Persistent AF termination during PVI may identify a subgroup of patients who experience a similar long-term clinical outcome with PVI ablation alone when compared with other more extensive persistent AF ablation strategies. Pulmonary vein isolation alone may be an appropriate tactic in this subgroup of persistent AF patients. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  19. Academic Emergency Medicine Physicians' Knowledge of Mechanical Ventilation.

    PubMed

    Wilcox, Susan R; Strout, Tania D; Schneider, Jeffrey I; Mitchell, Patricia M; Smith, Jessica; Lutfy-Clayton, Lucienne; Marcolini, Evie G; Aydin, Ani; Seigel, Todd A; Richards, Jeremy B

    2016-05-01

    Although emergency physicians frequently intubate patients, management of mechanical ventilation has not been emphasized in emergency medicine (EM) education or clinical practice. The objective of this study was to quantify EM attendings' education, experience, and knowledge regarding mechanical ventilation in the emergency department. We developed a survey of academic EM attendings' educational experiences with ventilators and a knowledge assessment tool with nine clinical questions. EM attendings at key teaching hospitals for seven EM residency training programs in the northeastern United States were invited to participate in this survey study. We performed correlation and regression analyses to evaluate the relationship between attendings' scores on the assessment instrument and their training, education, and comfort with ventilation. Of 394 EM attendings surveyed, 211 responded (53.6%). Of respondents, 74.5% reported receiving three or fewer hours of ventilation-related education from EM sources over the past year and 98 (46%) reported receiving between 0-1 hour of education. The overall correct response rate for the assessment tool was 73.4%, with a standard deviation of 19.9. The factors associated with a higher score were completion of an EM residency, prior emphasis on mechanical ventilation during one's own residency, working in a setting where an emergency physician bears primary responsibility for ventilator management, and level of comfort with managing ventilated patients. Physicians' comfort was associated with the frequency of ventilator changes and EM management of ventilation, as well as hours of education. EM attendings report caring for mechanically ventilated patients frequently, but most receive fewer than three educational hours a year on mechanical ventilation, and nearly half receive 0-1 hour. Physicians' performance on an assessment tool for mechanical ventilation is most strongly correlated with their self-reported comfort with mechanical

  20. [A comparison of leak compensation in six acute care ventilators during non-invasive ventilation].

    PubMed

    Hu, X S; Wang, Y; Wang, Z T; Yan, P; Zhang, X G; Zhao, S F; Xie, F; Gu, H J; Xie, L X

    2017-02-12

    Objective: To compare the ability of leak compensation in 6 medical ventilators during non-invasive ventilation. Methods: Six medical ventilators were selected, including 3 non-invasive ventilators (V60, Flexo and Stellar150), and 3 invasive ventilators(Avea, Servo I and BellaVist). Using a lung simulator, the ability of leak compensation was evaluated during triggering and cycling in 2 respiratory mechanics conditions (high airway resistance condition and high elastance resistance condition), and each condition was performed under 2 PEEP levels (4, and 8 cmH(2)O, 1 mmHg=0.098 kPa) at 4 air leak level conditions (L0: 2-3 L/min, L1: 8-10 L/min, L2: 22-27 L/min, L3: 35-40 L/min). Results: In the high elastance resistance condition (L2, L3)with different leak levels, the number of auto-triggering and miss-triggering of the non-invasive ventilator Flexo was significantly less than those of the others (L2: 1, 1; L3: 1.67, 1.33, P <0.01), and had better synchronization (L2: 2.33, 2.33; L3: 3.33, 3.33, P <0.01). In the high airway resistance condition with PEEP 4 cmH(2)O, V60 had less number of auto-triggering than other ventilators ( P <0.01), while in the high airway resistance condition with PEEP 8 cmH(2)O, Stellar150 had less number of miss-triggering than other ventilators (1, 0.67, 0, P <0.01). Flexo had a shorter trigger delay time than other ventilators in both high airway resistance and high elastance resistance conditions with L0 and L1 leak levels and PEEP levels [ARDS, PEEP=4: (109.8±1.8) ms, (112.0±0.6) ms; ARDS, PEEP=8: (103.1±0.7) ms, (109.7±0.7) ms; COPD, PEEP=4: (207.3±1.1) ms, (220.8±1.1) ms; COPD, PEEP=8: (195.6±6.7) ms, (200.0±1.2) ms , P <0.01]. Stellar150 had the shortest trigger delay time in high airway resistance condition with PEEP 4 cmH(2)O and high leak level L3[(262.8±0.8) ms , P <0.01]. V60 had a good performance on trigger delay time in high elastance resistance condition with PEEP 4 and 8 cmH(2)O, and also was most stable in

  1. Iatrogenic pneumothorax related to mechanical ventilation

    PubMed Central

    Hsu, Chien-Wei; Sun, Shu-Fen

    2014-01-01

    Pneumothorax is a potentially lethal complication associated with mechanical ventilation. Most of the patients with pneumothorax from mechanical ventilation have underlying lung diseases; pneumothorax is rare in intubated patients with normal lungs. Tension pneumothorax is more common in ventilated patients with prompt recognition and treatment of pneumothorax being important to minimize morbidity and mortality. Underlying lung diseases are associated with ventilator-related pneumothorax with pneumothoraces occurring most commonly during the early phase of mechanical ventilation. The diagnosis of pneumothorax in critical illness is established from the patients’ history, physical examination and radiological investigation, although the appearances of a pneumothorax on a supine radiograph may be different from the classic appearance on an erect radiograph. For this reason, ultrasonography is beneficial for excluding the diagnosis of pneumothorax. Respiration-dependent movement of the visceral pleura and lung surface with respect to the parietal pleura and chest wall can be easily visualized with transthoracic sonography given that the presence of air in the pleural space prevents sonographic visualization of visceral pleura movements. Mechanically ventilated patients with a pneumothorax require tube thoracostomy placement because of the high risk of tension pneumothorax. Small-bore catheters are now preferred in the majority of ventilated patients. Furthermore, if there are clinical signs of a tension pneumothorax, emergency needle decompression followed by tube thoracostomy is widely advocated. Patients with pneumothorax related to mechanical ventilation who have tension pneumothorax, a higher acute physiology and chronic health evaluation II score or PaO2/FiO2 < 200 mmHg were found to have higher mortality. PMID:24834397

  2. Closed loop ventilation mode in Intensive Care Unit: a randomized controlled clinical trial comparing the numbers of manual ventilator setting changes.

    PubMed

    Arnal, Jean-Michel; Garnero, Aude; Novotni, Dominik; Corno, Gaëlle; Donati, Stéphane-Yannis; Demory, Didier; Quintana, Gabrielle; Ducros, Laurent; Laubscher, Thomas; Durand-Gasselin, Jacques

    2018-01-01

    There is an equipoise regarding closed-loop ventilation modes and the ability to reduce workload for providers. On one hand some settings are managed by the ventilator but on another hand the automatic mode introduces new settings for the user. This randomized controlled trial compared the number of manual ventilator setting changes between a full closed loop ventilation and oxygenation mode (INTELLiVENT-ASV®) and conventional ventilation modes (volume assist control and pressure support) in Intensive Care Unit (ICU) patients. The secondary endpoints were to compare the number of arterial blood gas analysis, the sedation dose and the user acceptance. Sixty subjects with an expected duration of mechanical ventilation of at least 48 hours were randomized to be ventilated using INTELLiVENT-ASV® or conventional modes with a protocolized weaning. All manual ventilator setting changes were recorded continuously from inclusion to successful extubation or death. Arterial blood gases were performed upon decision of the clinician in charge. User acceptance score was assessed for nurses and physicians once daily using a Likert Scale. The number of manual ventilator setting changes per 24 h-period per subject was lower in INTELLiVENT-ASV® as compared to conventional ventilation group (5 [4-7] versus 10 [7-17]) manuals settings per subject per day [P<0.001]). The number of arterial blood gas analysis and the sedation doses were not significantly different between the groups. Nurses and physicians reported that INTELLiVENT-ASV® was significantly easier to use as compared to conventional ventilation (P<0.001 for nurses and P<0.01 for physicians). For mechanically ventilated ICU patients, INTELLiVENT-ASV® significantly reduces the number of manual ventilator setting changes with the same number of arterial blood gas analysis and sedation dose, and is easier to use for the caregivers as compared to conventional ventilation modes.

  3. Extracting uranium from seawater: Promising AF series adsorbents

    DOE PAGES

    Das, Sadananda; Oyola, Y.; Mayes, Richard T.; ...

    2015-11-02

    Here, a new family of high surface area polyethylene fiber adsorbents (AF series) was recently developed at the Oak Ridge National Laboratory (ORNL). The AF series of were synthesized by radiation-induced graft polymerization of acrylonitrile and itaconic acid (at different monomer/co-monomer mol ratios) onto high surface area polyethylene fibers. The degree of grafting (%DOG) of AF series adsorbents was found to be 154 354%. The grafted nitrile groups were converted to amidoxime groups by treating with hydroxylamine. The amidoximated adsorbents were then conditioned with 0.44M KOH at 80 C followed by screening at ORNL with simulated seawater spiked with 8more » ppm uranium. Uranium adsorption capacity in simulated seawater screening ranged from 170-200 g-U/kg-ads irrespective of %DOG. A monomer/co-monomer mol ratio in the range of 7.57-10.14 seemed to be optimum for highest uranium loading capacity. Subsequently, the adsorbents were also tested with natural seawater at Pacific Northwest National Laboratory (PNNL) using flow-through exposure uptake experiments to determine uranium loading capacity with varying KOH conditioning time at 80 C. The highest adsorption capacity of AF1 measured after 56 days of marine testing was demonstrated as 3.9 g-U/kg-adsorbent and 3.2 g-U/kg-adsorbent for 1hr and 3hrs of KOH conditioning at 80 C, respectively. Based on capacity values of several AF1 samples, it was observed that changing KOH conditioning from 3hrs to 1hr at 80 C resulted in 22-27% increase in uranium loading capacity in seawater.« less

  4. Extracting Uranium from Seawater: Promising AF Series Adsorbents

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

    Das, S.; Oyola, Y.; Mayes, Richard T.

    A new family of high-surface-area polyethylene fiber adsorbents named the AF series was recently developed at the Oak Ridge National Laboratory (ORNL). The AF series adsorbents were synthesized by radiation-induced graft polymerization of acrylonitrile and itaconic acid (at different monomer/comonomer mol ratios) onto high surface area polyethylene fibers. The degree of grafting (%DOG) of AF series adsorbents was found to be 154-354%. The grafted nitrile groups were converted to amidoxime groups by treating with hydroxylamine. The amidoximated adsorbents were then conditioned with 0.44 M KOH at 80 °C followed by screening at ORNL with sodium-based synthetic aqueous solution, spiked withmore » 8 ppm uranium. The uranium adsorption capacity in simulated seawater screening ranged from 170 to 200 g-U/kg-ads irrespective of %DOG. A monomer/comonomer molar ratio in the range of 7.57-10.14 seemed to be optimum for highest uranium loading capacity. Subsequently, the adsorbents were also tested with natural seawater at Pacific Northwest National Laboratory (PNNL) using flow-through column experiments to determine uranium loading capacity with varying KOH conditioning times at 80 °C. The highest adsorption capacity of AF1 measured after 56 days of marine testing was demonstrated as 3.9 g-U/kg-adsorbent and 3.2 g-U/kg-adsorbent for 1 and 3 h of KOH conditioning at 80 °C, respectively. Based on capacity values of several AF1 samples, it was observed that changing KOH conditioning from 1 to 3 h at 80 °C resulted in a 22-27% decrease in uranium adsorption capacity in seawater.« less

  5. Extracting uranium from seawater: Promising AF series adsorbents

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

    Das, Sadananda; Oyola, Y.; Mayes, Richard T.

    Here, a new family of high surface area polyethylene fiber adsorbents (AF series) was recently developed at the Oak Ridge National Laboratory (ORNL). The AF series of were synthesized by radiation-induced graft polymerization of acrylonitrile and itaconic acid (at different monomer/co-monomer mol ratios) onto high surface area polyethylene fibers. The degree of grafting (%DOG) of AF series adsorbents was found to be 154 354%. The grafted nitrile groups were converted to amidoxime groups by treating with hydroxylamine. The amidoximated adsorbents were then conditioned with 0.44M KOH at 80 C followed by screening at ORNL with simulated seawater spiked with 8more » ppm uranium. Uranium adsorption capacity in simulated seawater screening ranged from 170-200 g-U/kg-ads irrespective of %DOG. A monomer/co-monomer mol ratio in the range of 7.57-10.14 seemed to be optimum for highest uranium loading capacity. Subsequently, the adsorbents were also tested with natural seawater at Pacific Northwest National Laboratory (PNNL) using flow-through exposure uptake experiments to determine uranium loading capacity with varying KOH conditioning time at 80 C. The highest adsorption capacity of AF1 measured after 56 days of marine testing was demonstrated as 3.9 g-U/kg-adsorbent and 3.2 g-U/kg-adsorbent for 1hr and 3hrs of KOH conditioning at 80 C, respectively. Based on capacity values of several AF1 samples, it was observed that changing KOH conditioning from 3hrs to 1hr at 80 C resulted in 22-27% increase in uranium loading capacity in seawater.« less

  6. CERN’s AFS replacement project

    NASA Astrophysics Data System (ADS)

    Iven, J.; Lamanna, M.; Pace, A.

    2017-10-01

    OpenAFS is the legacy solution for a variety of use cases at CERN, most notably home-directory services. OpenAFS has been used as the primary shared file-system for Linux (and other) clients for more than 20 years, but despite an excellent track record, the project’s age and architectural limitations are becoming more evident. We are now working to offer an alternative solution based on existing CERN storage services. The new solution will offer evolved functionality, and is expected to eventually benefit from operational synergies. In this paper we will present CERN’s usage and an analysis of our technical choices: we will focus on the alternatives chosen for the various use cases (among them EOS, CERNBox and CASTOR); on implementing the migration process over the coming years; and the challenges and opportunities of the migration.

  7. Mechanical Ventilation: State of the Art.

    PubMed

    Pham, Tài; Brochard, Laurent J; Slutsky, Arthur S

    2017-09-01

    Mechanical ventilation is the most used short-term life support technique worldwide and is applied daily for a diverse spectrum of indications, from scheduled surgical procedures to acute organ failure. This state-of-the-art review provides an update on the basic physiology of respiratory mechanics, the working principles, and the main ventilatory settings, as well as the potential complications of mechanical ventilation. Specific ventilatory approaches in particular situations such as acute respiratory distress syndrome and chronic obstructive pulmonary disease are detailed along with protective ventilation in patients with normal lungs. We also highlight recent data on patient-ventilator dyssynchrony, humidified high-flow oxygen through nasal cannula, extracorporeal life support, and the weaning phase. Finally, we discuss the future of mechanical ventilation, addressing avenues for improvement. Copyright © 2017 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  8. Pandemic ventilator rationing and appeals processes.

    PubMed

    Patrone, Daniel; Resnik, David

    2011-06-01

    In a severe influenza pandemic, hospitals will likely experience serious and widespread shortages of patient pulmonary ventilators and of staff qualified to operate them. Deciding who will receive access to mechanical ventilation will often determine who lives and who dies. This prospect raises an important question whether pandemic preparedness plans should include some process by which individuals affected by ventilator rationing would have the opportunity to appeal adverse decisions. However, the issue of appeals processes to ventilator rationing decisions has been largely neglected in state pandemic planning efforts. If we are to devise just and effective plans for coping with a severe influenza pandemic, more attention to the issue of appeals processes for pandemic ventilator rationing decisions is needed. Arguments for and against appeals processes are considered, and some suggestions are offered to help efforts at devising more rational pandemic preparedness plans.

  9. Outcome-based ventilation: A framework for assessing performance, health, and energy impacts to inform office building ventilation decisions.

    PubMed

    Rackes, A; Ben-David, T; Waring, M S

    2018-07-01

    This article presents an outcome-based ventilation (OBV) framework, which combines competing ventilation impacts into a monetized loss function ($/occ/h) used to inform ventilation rate decisions. The OBV framework, developed for U.S. offices, considers six outcomes of increasing ventilation: profitable outcomes realized from improvements in occupant work performance and sick leave absenteeism; health outcomes from occupant exposure to outdoor fine particles and ozone; and energy outcomes from electricity and natural gas usage. We used the literature to set low, medium, and high reference values for OBV loss function parameters, and evaluated the framework and outcome-based ventilation rates using a simulated U.S. office stock dataset and a case study in New York City. With parameters for all outcomes set at medium values derived from literature-based central estimates, higher ventilation rates' profitable benefits dominated negative health and energy impacts, and the OBV framework suggested ventilation should be ≥45 L/s/occ, much higher than the baseline ~8.5 L/s/occ rate prescribed by ASHRAE 62.1. Only when combining very low parameter estimates for profitable impacts with very high ones for health and energy impacts were all outcomes on the same order. Even then, however, outcome-based ventilation rates were often twice the baseline rate or more. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Adaptive support ventilation: State of the art review

    PubMed Central

    Fernández, Jaime; Miguelena, Dayra; Mulett, Hernando; Godoy, Javier; Martinón-Torres, Federico

    2013-01-01

    Mechanical ventilation is one of the most commonly applied interventions in intensive care units. Despite its life-saving role, it can be a risky procedure for the patient if not applied appropriately. To decrease risks, new ventilator modes continue to be developed in an attempt to improve patient outcomes. Advances in ventilator modes include closed-loop systems that facilitate ventilator manipulation of variables based on measured respiratory parameters. Adaptive support ventilation (ASV) is a positive pressure mode of mechanical ventilation that is closed-loop controlled, and automatically adjust based on the patient's requirements. In order to deliver safe and appropriate patient care, clinicians need to achieve a thorough understanding of this mode, including its effects on underlying respiratory mechanics. This article will discuss ASV while emphasizing appropriate ventilator settings, their advantages and disadvantages, their particular effects on oxygenation and ventilation, and the monitoring priorities for clinicians. PMID:23833471

  11. Efficacy of an expanded ventilator bundle for the reduction of ventilator-associated pneumonia in the medical intensive care unit.

    PubMed

    Blamoun, John; Alfakir, Maria; Rella, Marie E; Wojcik, Janice M; Solis, Roberto A; Anees Khan, M; DeBari, Vincent A

    2009-03-01

    The ventilator bundle (VB) includes a group of clinical maneuvers (head-of-bed elevation, "sedation vacation," deep vein thrombosis prophylaxis, and peptic ulcer disease prophylaxis) to improve outcomes in patients undergoing mechanical ventilation. We modified the standard VB in our medical intensive care unit to include a group of respiratory therapist-driven protocols and, postimplementation, observed a statistically significant (P = .0006) reduction in ventilator-associated pneumonia (VAP), from a median of 14.1 cases/10(3) ventilator-days (interquartile range [IQR] = 12.1 to 20.6) to 0 cases/10(3) ventilator-days (IQR = 0 to 1.1).

  12. 46 CFR 154.1200 - Mechanical ventilation system: General.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Mechanical ventilation system: General. 154.1200 Section... Equipment Cargo Area: Mechanical Ventilation System § 154.1200 Mechanical ventilation system: General. (a... cargo handling equipment must have a fixed, exhaust-type mechanical ventilation system. (b) The...

  13. Influences of Duration of Inspiratory Effort, Respiratory Mechanics, and Ventilator Type on Asynchrony With Pressure Support and Proportional Assist Ventilation.

    PubMed

    Vasconcelos, Renata S; Sales, Raquel P; Melo, Luíz H de P; Marinho, Liégina S; Bastos, Vasco Pd; Nogueira, Andréa da Nc; Ferreira, Juliana C; Holanda, Marcelo A

    2017-05-01

    Pressure support ventilation (PSV) is often associated with patient-ventilator asynchrony. Proportional assist ventilation (PAV) offers inspiratory assistance proportional to patient effort, minimizing patient-ventilator asynchrony. The objective of this study was to evaluate the influence of respiratory mechanics and patient effort on patient-ventilator asynchrony during PSV and PAV plus (PAV+). We used a mechanical lung simulator and studied 3 respiratory mechanics profiles (normal, obstructive, and restrictive), with variations in the duration of inspiratory effort: 0.5, 1.0, 1.5, and 2.0 s. The Auto-Trak system was studied in ventilators when available. Outcome measures included inspiratory trigger delay, expiratory trigger asynchrony, and tidal volume (V T ). Inspiratory trigger delay was greater in the obstructive respiratory mechanics profile and greatest with a effort of 2.0 s (160 ms); cycling asynchrony, particularly delayed cycling, was common in the obstructive profile, whereas the restrictive profile was associated with premature cycling. In comparison with PSV, PAV+ improved patient-ventilator synchrony, with a shorter triggering delay (28 ms vs 116 ms) and no cycling asynchrony in the restrictive profile. V T was lower with PAV+ than with PSV (630 mL vs 837 mL), as it was with the single-limb circuit ventilator (570 mL vs 837 mL). PAV+ mode was associated with longer cycling delays than were the other ventilation modes, especially for the obstructive profile and higher effort values. Auto-Trak eliminated automatic triggering. Mechanical ventilation asynchrony was influenced by effort, respiratory mechanics, ventilator type, and ventilation mode. In PSV mode, delayed cycling was associated with shorter effort in obstructive respiratory mechanics profiles, whereas premature cycling was more common with longer effort and a restrictive profile. PAV+ prevented premature cycling but not delayed cycling, especially in obstructive respiratory mechanics

  14. Duration of Mechanical Ventilation in the Emergency Department.

    PubMed

    Angotti, Lauren B; Richards, Jeremy B; Fisher, Daniel F; Sankoff, Jeffrey D; Seigel, Todd A; Al Ashry, Haitham S; Wilcox, Susan R

    2017-08-01

    Due to hospital crowding, mechanically ventilated patients are increasingly spending hours boarding in emergency departments (ED) before intensive care unit (ICU) admission. This study aims to evaluate the association between time ventilated in the ED and in-hospital mortality, duration of mechanical ventilation, ICU and hospital length of stay (LOS). This was a multi-center, prospective, observational study of patients ventilated in the ED, conducted at three academic Level I Trauma Centers from July 2011 to March 2013. All consecutive adult patients on invasive mechanical ventilation were eligible for enrollment. We performed a Cox regression to assess for a mortality effect for mechanically ventilated patients with each hour of increasing LOS in the ED and multivariable regression analyses to assess for independently significant contributors to in-hospital mortality. Our primary outcome was in-hospital mortality, with secondary outcomes of ventilator days, ICU LOS and hospital LOS. We further commented on use of lung protective ventilation and frequency of ventilator changes made in this cohort. We enrolled 535 patients, of whom 525 met all inclusion criteria. Altered mental status without respiratory pathology was the most common reason for intubation, followed by trauma and respiratory failure. Using iterated Cox regression, a mortality effect occurred at ED time of mechanical ventilation > 7 hours, and the longer ED stay was also associated with a longer total duration of intubation. However, adjusted multivariable regression analysis demonstrated only older age and admission to the neurosciences ICU as independently associated with increased mortality. Of interest, only 23.8% of patients ventilated in the ED for over seven hours had changes made to their ventilator. In a prospective observational study of patients mechanically ventilated in the ED, there was a significant mortality benefit to expedited transfer of patients into an appropriate ICU setting.

  15. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Mechanical ventilation system: Standards. 154.1205... Equipment Cargo Area: Mechanical Ventilation System § 154.1205 Mechanical ventilation system: Standards. (a) Each exhaust type mechanical ventilation system required under § 154.1200 (a) must have ducts for...

  16. Artificial humidification for the mechanically ventilated patient.

    PubMed

    Selvaraj, N

    Caring for patients who are mechanically ventilated poses many challenges for critical care nurses. It is important to humidify the patient's airways artificially to prevent complications such as ventilator-associated pneumonia. There is no gold standard to determine which type of humidification is best for patients who are artificially ventilated. This article provides an overview of commonly used artificial humidification for mechanically ventilated patients and discusses nurses' responsibilities in caring for patients receiving artificial humidification.

  17. TH-E-BRF-02: 4D-CT Ventilation Image-Based IMRT Plans Are Dosimetrically Comparable to SPECT Ventilation Image-Based Plans

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

    Kida, S; University of Tokyo Hospital, Bunkyo, Tokyo; Bal, M

    Purpose: An emerging lung ventilation imaging method based on 4D-CT can be used in radiotherapy to selectively avoid irradiating highly-functional lung regions, which may reduce pulmonary toxicity. Efforts to validate 4DCT ventilation imaging have been focused on comparison with other imaging modalities including SPECT and xenon CT. The purpose of this study was to compare 4D-CT ventilation image-based functional IMRT plans with SPECT ventilation image-based plans as reference. Methods: 4D-CT and SPECT ventilation scans were acquired for five thoracic cancer patients in an IRB-approved prospective clinical trial. The ventilation images were created by quantitative analysis of regional volume changes (amore » surrogate for ventilation) using deformable image registration of the 4D-CT images. A pair of 4D-CT ventilation and SPECT ventilation image-based IMRT plans was created for each patient. Regional ventilation information was incorporated into lung dose-volume objectives for IMRT optimization by assigning different weights on a voxel-by-voxel basis. The objectives and constraints of the other structures in the plan were kept identical. The differences in the dose-volume metrics have been evaluated and tested by a paired t-test. SPECT ventilation was used to calculate the lung functional dose-volume metrics (i.e., mean dose, V20 and effective dose) for both 4D-CT ventilation image-based and SPECT ventilation image-based plans. Results: Overall there were no statistically significant differences in any dose-volume metrics between the 4D-CT and SPECT ventilation imagebased plans. For example, the average functional mean lung dose of the 4D-CT plans was 26.1±9.15 (Gy), which was comparable to 25.2±8.60 (Gy) of the SPECT plans (p = 0.89). For other critical organs and PTV, nonsignificant differences were found as well. Conclusion: This study has demonstrated that 4D-CT ventilation image-based functional IMRT plans are dosimetrically comparable to SPECT ventilation

  18. One-Lung Ventilation with Additional Ipsilateral Ventilation of Low Tidal Volume and High Frequency in Lung Lobectomy

    PubMed Central

    Feng, Yong; Wang, Jianyue; Zhang, Yang; Wang, Shiduan

    2016-01-01

    Background To investigate the protective effects of additional ipsilateral ventilation of low tidal volume and high frequency on lung functions in the patients receiving lobectomy. Material/Methods Sixty patients receiving lung lobectomy were randomized into the conventional one-lung ventilation (CV) group (n=30) and the ipsilateral low tidal volume high frequency ventilation (LV) group (n=30). In the CV group, patients received only contralateral OLV. In the LV group, patients received contralateral ventilation and additional ipsilateral ventilation of low tidal volume of 1–2 ml/kg and high frequency of 40 times/min. Normal lung tissues were biopsied for the analysis of lung injury. Lung injury was scored by evaluating interstitial edema, alveolar edema, neutrophil infiltration, and alveolar congestion. Results At 30 min and 60 min after the initiation of one-lung ventilation and after surgery, patients in the LV group showed significantly higher ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen than those in the CV group (P<0.001). Lung injury was significantly less severe (2.7±0.7) in the LV group than in the CV group (3.1±0.7) (P=0.006). Conclusions Additional ipsilateral ventilation of low tidal volume and high frequency can decrease the risk of hypoxemia and alleviate lung injury in patients receiving lobectomy. PMID:27166086

  19. Natural ventilation of buildings: opposing wind and buoyancy

    NASA Astrophysics Data System (ADS)

    Linden, Paul; Hunt, Gary

    1998-11-01

    The use of natural ventilation in buildings is an attractive way to reduce energy usage thereby reducing costs and CO2 emissions. Generally, it is necessary to remove excess heat from a building and the designer can use the buoyancy forces associated with the above ambient temperatures within the building to drive a flow - 'stack' ventilation. The most efficient mode is displacement ventilation where warm air accumulates near the top of the building and flows out through upper level vents and cooler air flows in at lower levels. Ventilation will also be driven between these lower and upper openings by the wind. We report on laboratory modeling and theory which investigates the effects of an opposing wind on stack ventilation driven by a constant source of heat within a space under displacement ventilation. We show that there is a critical wind speed, expressed in dimensionless terms as a critical Froude number, above which displacement ventilation is replaced by (less efficient) mixing ventilation with reversed flow. Below this critical speed, displacement ventilation, in which the interior has a two-layer stratification, is maintained. The criterion for the change in ventilation mode is derived from general considerations of mixing efficiencies in stratified flows. We conclude that even when wind effects might appear to be dominant, the inhibition of mixing by the stable stratification within the space ensures that stack ventilation can operate over a wide range of apparently adverse conditions.

  20. Ventilation via Cut Nasotracheal Tube During General Anesthesia

    PubMed Central

    Asahi, Yoshinao; Omichi, Shiro; Adachi, Seita; Kagamiuchi, Hajime; Kotani, Junichiro

    2013-01-01

    Many patients with disabilities need recurrent dental treatment under general anesthesia because of high caries prevalence and the nature of dental treatment. We evaluated the use of a nasal device as a possible substitute for flexible laryngeal mask airway to reduce the risk of unexpected failure accompanying intubation; we succeeded in ventilating the lungs with a cut nasotracheal tube (CNT) with its tip placed in the pharynx. We hypothesized that this technique would be useful during dental treatment under general anesthesia and investigated its usefulness as part of a minimally invasive technique. A prospective study was designed using general anesthesia in 37 dental patients with disabilities such as intellectual impairment, autism, and cerebral palsy. CNT ventilation was compared with mask ventilation with the patient in 3 positions: the neck in flexion, horizontal position, and in extension. The effect of mouth gags was also recorded during CNT ventilation. The percentages of cases with effective ventilation were similar for the 2 techniques in the neck extension and horizontal positions (89.2–97.3%). However, CNT ventilation was significantly more effective than mask ventilation in the neck flexion position (94.6 vs 45.9%; P < .0001). Mouth gags slightly reduced the rate of effective ventilation in the neck flexion position. Most dental treatments involving minor oral surgeries were performed using mouth gags during CNT ventilation. CNT ventilation was shown to be superior to mask ventilation and is useful during dental treatment under general anesthesia. PMID:23506278

  1. Clinical review: Long-term noninvasive ventilation

    PubMed Central

    Robert, Dominique; Argaud, Laurent

    2007-01-01

    Noninvasive positive ventilation has undergone a remarkable evolution over the past decades and is assuming an important role in the management of both acute and chronic respiratory failure. Long-term ventilatory support should be considered a standard of care to treat selected patients following an intensive care unit (ICU) stay. In this setting, appropriate use of noninvasive ventilation can be expected to improve patient outcomes, reduce ICU admission, enhance patient comfort, and increase the efficiency of health care resource utilization. Current literature indicates that noninvasive ventilation improves and stabilizes the clinical course of many patients with chronic ventilatory failure. Noninvasive ventilation also permits long-term mechanical ventilation to be an acceptable option for patients who otherwise would not have been treated if tracheostomy were the only alternative. Nevertheless, these results appear to be better in patients with neuromuscular/-parietal disorders than in chronic obstructive pulmonary disease. This clinical review will address the use of noninvasive ventilation (not including continuous positive airway pressure) mainly in diseases responsible for chronic hypoventilation (that is, restrictive disorders, including neuromuscular disease and lung disease) and incidentally in others such as obstructive sleep apnea or problems of central drive. PMID:17419882

  2. Pandemic Ventilator Rationing and Appeals Processes

    PubMed Central

    Patrone, Daniel; Resnik, David

    2014-01-01

    In a severe influenza pandemic, hospitals will likely experience serious and widespread shortages of patient pulmonary ventilators and of staff qualified to operate them. Deciding who will receive access to mechanical ventilation will often determine who lives and who dies. This prospect raises an important question whether pandemic preparedness plans should include some process by which individuals affected by ventilator rationing would have the opportunity to appeal adverse decisions. However, the issue of appeals processes to ventilator rationing decisions has been largely neglected in state pandemic planning efforts. If we are to devise just and effective plans for coping with a severe influenza pandemic, more attention to the issue of appeals processes for pandemic ventilator rationing decisions is needed. Arguments for and against appeals processes are considered, and some suggestions are offered to help efforts at devising more rational pandemic preparedness plans. PMID:20354793

  3. [Lung protective ventilation - pathophysiology and diagnostics].

    PubMed

    Uhlig, Stefan; Frerichs, Inéz

    2008-06-01

    Mechanical ventilation may lead to lung injury depending on the ventilatory settings (e.g. pressure amplitudes, endexpiratory pressures, frequency) and the length of mechanical ventilation. Particularly in the inhomogeneously injured lungs of ARDS patients, alveolar overextension results in volutrauma, cyclic opening and closure of alveolar units in atelectrauma. Particularly important appears to be the fact that these processes may also cause biotrauma, i.e. the ventilator-induced hyperactivation of inflammatory responses in the lung. These side effects are reduced, but not eliminated with the currently recommended ventilation strategy with a tidal volume of 6 ml/kg idealized body weight. It is our hope that in the future optimization of ventilator settings will be facilated by bedside monitoring of novel indices of respiratory mechanics such as the stress index or the Slice technique, and by innovative real-time imaging technologies such as electrical impedance tomography.

  4. Lung-protective mechanical ventilation does not protect against acute kidney injury in patients without lung injury at onset of mechanical ventilation.

    PubMed

    Cortjens, Bart; Royakkers, Annick A N M; Determann, Rogier M; van Suijlen, Jeroen D E; Kamphuis, Stephan S; Foppen, Jannetje; de Boer, Anita; Wieland, Cathrien W; Spronk, Peter E; Schultz, Marcus J; Bouman, Catherine S C

    2012-06-01

    Preclinical and clinical studies suggest that mechanical ventilation contributes to the development of acute kidney injury (AKI), particularly in the setting of lung-injurious ventilator strategies. To determine whether ventilator settings in critically ill patients without acute lung injury (ALI) at onset of mechanical ventilation affect the development of AKI. Secondary analysis of a randomized controlled trial (N = 150), comparing conventional tidal volume (V(T), 10 mL/kg) with low tidal volume (V(T), 6 mL/kg) mechanical ventilation in critically ill patients without ALI at randomization. During the first 5 days of mechanical ventilation, the RIFLE class was determined daily, whereas neutrophil gelatinase-associated lipocalin and cystatin C levels were measured in plasma collected on days 0, 2, and 4. Eighty-six patients had no AKI at inclusion, and 18 patients (21%) subsequently developed AKI, but without significant difference between ventilation strategies. (Cumulative hazard, 0.26 vs 0.23; P = .88.) The courses of neutrophil gelatinase-associated lipocalin and cystatin C plasma levels did not differ significantly between randomization groups. In the present study in critically patients without ALI at onset of mechanical ventilation, lower tidal volume ventilation did not reduce the development or worsening of AKI compared with conventional tidal volume ventilation. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. U2AF1 mutations alter splice site recognition in hematological malignancies.

    PubMed

    Ilagan, Janine O; Ramakrishnan, Aravind; Hayes, Brian; Murphy, Michele E; Zebari, Ahmad S; Bradley, Philip; Bradley, Robert K

    2015-01-01

    Whole-exome sequencing studies have identified common mutations affecting genes encoding components of the RNA splicing machinery in hematological malignancies. Here, we sought to determine how mutations affecting the 3' splice site recognition factor U2AF1 alter its normal role in RNA splicing. We find that U2AF1 mutations influence the similarity of splicing programs in leukemias, but do not give rise to widespread splicing failure. U2AF1 mutations cause differential splicing of hundreds of genes, affecting biological pathways such as DNA methylation (DNMT3B), X chromosome inactivation (H2AFY), the DNA damage response (ATR, FANCA), and apoptosis (CASP8). We show that U2AF1 mutations alter the preferred 3' splice site motif in patients, in cell culture, and in vitro. Mutations affecting the first and second zinc fingers give rise to different alterations in splice site preference and largely distinct downstream splicing programs. These allele-specific effects are consistent with a computationally predicted model of U2AF1 in complex with RNA. Our findings suggest that U2AF1 mutations contribute to pathogenesis by causing quantitative changes in splicing that affect diverse cellular pathways, and give insight into the normal function of U2AF1's zinc finger domains. © 2015 Ilagan et al.; Published by Cold Spring Harbor Laboratory Press.

  6. Persistent Atrial Fibrillation Ablation in Females: Insight from the MAGIC-AF Trial.

    PubMed

    Singh, Sheldon M; D'Avila, Andre; Aryana, Arash; Kim, Young-Hoon; Mangrum, J Michael; Michaud, Gregory F; Dukkipati, Srinivas R; Heist, E Kevin; Barrett, Conor D; Thorpe, Kevin E; Reddy, Vivek Y

    2016-07-27

    Atrial fibrillation (AF) ablation is less frequently performed in women when compared to men. There are conflicting data on the safety and efficacy of AF ablation in women. The objective of this study was to compare the clinical characteristics and outcomes in a contemporary cohort of men and women undergoing persistent AF ablation procedures. A total of 182 men and 53 women undergoing a first-ever persistent AF catheter ablation procedure in The Modified Ablation Guided by Ibutilide Use in Chronic Atrial Fibrillation (MAGIC-AF) trial were evaluated. Clinical and procedural characteristics were compared between each gender. The primary efficacy endpoint was the 1-year single procedure freedom from atrial arrhythmia off anti-arrhythmic drugs. Women undergoing catheter ablation procedures were older than men (P < 0.001). The duration of AF and associated co-morbidities were similar between both genders. Single procedure drug-free atrial arrhythmia recurrence occurred in 53% of the cohort with no difference based on gender (men = 54%, women = 53%; P = 1.0). Procedural (P = 0.04), fluoroscopic (P = 0.02), and ablation times (P = 0.003) were shorter in women compared to men. Periprocedural complications and postablation improvement in quality of life were similar between men and women. Women undergoing a first-ever persistent AF ablation procedure were older but had similar clinical outcomes and complications when compared with men. © 2016 Wiley Periodicals, Inc.

  7. The Effect of Pressure-Controlled Ventilation and Volume-Controlled Ventilation in Prone Position on Pulmonary Mechanics and Inflammatory Markers.

    PubMed

    Şenay, Hasan; Sıvacı, Remziye; Kokulu, Serdar; Koca, Buğra; Bakı, Elif Doğan; Ela, Yüksel

    2016-08-01

    The aim of this present study is to compare the effect of pressure-controlled ventilation and volume-controlled ventilation on pulmonary mechanics and inflammatory markers in prone position. The study included 41 patients undergoing to vertebrae surgery. The patients were randomized into two groups: Group 1 received volume-controlled ventilation, while group 2 received pressure-controlled ventilation. The demographic data, pulmonary mechanics, the inflammatory marker levels just after the induction of anesthetics, at the 6th and 12th hours, and gas analysis from arterial blood samples taken at the beginning and the 30th minute were recorded. The inflammatory marker levels increased in both groups, without any significant difference among groups. Peak inspiratory pressure level was higher in the volume-controlled ventilation group. This study revealed that there is no difference regarding inflammatory marker levels between volume- and pressure-controlled ventilation.

  8. Embossed Teflon AF Laminate Membrane Microfluidic Diaphragm Valves

    NASA Technical Reports Server (NTRS)

    Willis, Peter; Hunt, Brian; White,Victor; Grunthaner, Frank

    2008-01-01

    A microfluidic system has been designed to survive spaceflight and to function autonomously on the Martian surface. It manipulates microscopic quantities of liquid water and performs chemical analyses on these samples to assay for the presence of molecules associated with past or present living processes. This technology lies at the core of the Urey Instrument, which is scheduled for inclusion on the Pasteur Payload of the ESA ExoMars rover mission in 2013. Fabrication processes have been developed to make the microfabricated Teflon-AF microfluidic diaphragm pumps capable of surviving extreme temperature excursions before and after exposure to liquid water. Two glass wafers are etched with features and a continuous Teflon membrane is sandwiched between them (see figure). Single valves are constructed using this geometry. The microfabricated devices are then post processed by heating the assembled device while applying pneumatic pressure to force the Teflon diaphragm against the valve seat while it is softened. After cooling the device, the embossed membrane retains this new shape. This solves previous problems with bubble introduction into the fluid flow where deformations of the membrane at the valve seat occurred during device bonding at elevated temperatures (100-150 C). The use of laminated membranes containing commercial Teflon AF 2400 sheet sandwiched between spun Teflon AF 1600 layers performed best, and were less gas permeable than Teflon AF 1600 membranes on their own. Spinning Teflon AF 1600 solution (6 percent in FLOURINERT(Registered TradeMark) FC40 solvent, 3M Company) at 500 rpm for 1.5 seconds, followed by 1,000 rpm for 3 seconds onto Borofloat glass wafers, results in a 10-micron-thick film of extremely smooth Teflon AF. This spinning process is repeated several times on flat, blank, glass wafers in order to gradually build a thick, smooth membrane. After running this process at least five times, the wafer and Teflon coating are heated under vacuum

  9. Performance of Portable Ventilators at Altitude

    DTIC Science & Technology

    2015-03-30

    collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT...Deploying ventilators that can maintain a consistent tidal volume (VT) delivery at various altitudes is imperative for lung protection when...performance of mechanical ventilators calibrated for operation at sea level. Deploying ventilators that can maintain a consistent tidal volume (VT) delivery

  10. Physiological Effects of Positive Pressure Ventilation.

    DTIC Science & Technology

    1992-05-01

    function in the patient with respiratory failure . In R. R. Kirby, M. J. Banner, & J. B. Downs (Eds.), Clinical Applications of Ventilatory Su2Rort (pp. 301...G., Blehschmidt, N. G., & Linder, W. J. (1990). Positive-pressure ventilation with positive end-expiratory pressure and atrial natriuretic peptide ...Acute Resniratorv Failure . New York: Churchill Livingstone. Ventilation 1 Physiological Effects of Positive Pressure Ventilation Dennis L. Oakes, RN, BSN

  11. The ventilation problem in schools: literature review

    DOE PAGES

    Fisk, W. J.

    2017-07-06

    Based on a review of literature published in refereed archival journals, ventilation rates in classrooms often fall far short of the minimum ventilation rates specified in standards. We report that there is compelling evidence, from both cross-sectional and intervention studies, of an association of increased student performance with increased ventilation rates. There is evidence that reduced respiratory health effects and reduced student absence are associated with increased ventilation rates. Increasing ventilation rates in schools imposes energy costs and can increase heating, ventilating, and air-conditioning system capital costs. The net annual costs, ranging from a few dollars to about 10 dollarsmore » per person, are less than 0.1% of typical public spending on elementary and secondary education in the United States. Finally, such expenditures seem like a small price to pay given the evidence of health and performance benefits.« less

  12. The ventilation problem in schools: literature review

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

    Fisk, W. J.

    Based on a review of literature published in refereed archival journals, ventilation rates in classrooms often fall far short of the minimum ventilation rates specified in standards. We report that there is compelling evidence, from both cross-sectional and intervention studies, of an association of increased student performance with increased ventilation rates. There is evidence that reduced respiratory health effects and reduced student absence are associated with increased ventilation rates. Increasing ventilation rates in schools imposes energy costs and can increase heating, ventilating, and air-conditioning system capital costs. The net annual costs, ranging from a few dollars to about 10 dollarsmore » per person, are less than 0.1% of typical public spending on elementary and secondary education in the United States. Finally, such expenditures seem like a small price to pay given the evidence of health and performance benefits.« less

  13. Numerical simulation and comparison of two ventilation methods for a restaurant - displacement vs mixed flow ventilation

    NASA Astrophysics Data System (ADS)

    Chitaru, George; Berville, Charles; Dogeanu, Angel

    2018-02-01

    This paper presents a comparison between a displacement ventilation method and a mixed flow ventilation method using computational fluid dynamics (CFD) approach. The paper analyses different aspects of the two systems, like the draft effect in certain areas, the air temperatureand velocity distribution in the occupied zone. The results highlighted that the displacement ventilation system presents an advantage for the current scenario, due to the increased buoyancy driven flows caused by the interior heat sources. For the displacement ventilation case the draft effect was less prone to appear in the occupied zone but the high heat emissions from the interior sources have increased the temperature gradient in the occupied zone. Both systems have been studied in similar conditions, concentrating only on the flow patterns for each case.

  14. Bias flow rate and ventilation efficiency during adult high-frequency oscillatory ventilation: a lung model study.

    PubMed

    Nagano, Osamu; Yumoto, Tetsuya; Nishimatsu, Atsunori; Kanazawa, Shunsuke; Fujita, Takahisa; Asaba, Sunao; Yamanouchi, Hideo

    2018-04-19

    Bias flow (BF) is essential to maintain mean airway pressure (MAP) and to washout carbon dioxide (CO 2 ) from the oscillator circuit during high-frequency oscillatory ventilation (HFOV). If the BF rate is inadequate, substantial CO 2 rebreathing could occur and ventilation efficiency could worsen. With lower ventilation efficiency, the required stroke volume (SV) would increase in order to obtain the same alveolar ventilation with constant frequency. The aim of this study was to assess the effect of BF rate on ventilation efficiency during adult HFOV. The R100 oscillator (Metran, Japan) was connected to an original lung model internally equipped with a simulated bronchial tree. The actual SV was measured with a flow sensor placed at the Y-piece. Carbon dioxide (CO 2 ) was continuously insufflated into the lung model ([Formula: see text]CO 2 ), and the partial pressure of CO 2 (PCO 2 ) in the lung model was monitored. Alveolar ventilation ([Formula: see text]A) was estimated as [Formula: see text]CO 2 divided by the stabilized value of PCO 2 . [Formula: see text]A was evaluated by setting SV from 80 to 180 mL (10 mL increments, n = 5) at a frequency of 8 Hz, a MAP of 25 cmH 2 O, and a BF of 10, 20, 30, and 40 L/min (study 1). Ventilation efficiency was calculated as [Formula: see text]A divided by the actual minute volume. The experiment was also performed with an actual SV of 80, 100, and 120 mL and a BF from 10 to 60 L/min (10 L/min increments: study 2). Study 1: With the same setting SV, the [Formula: see text]A with a BF of 20 L/min or more was significantly higher than that with a BF of 10 L/min. Study 2: With the same actual SV, the [Formula: see text]A and the ventilation efficiency with a BF of 30 L/min or more were significantly higher than those with a BF of 10 or 20 L/min. Increasing BF up to 30 L/min or more improved ventilation efficiency in the R100 oscillator.

  15. Effect of Dexmedetomidine on Mortality and Ventilator-Free Days in Patients Requiring Mechanical Ventilation With Sepsis

    PubMed Central

    Kawazoe, Yu; Miyamoto, Kyohei; Morimoto, Takeshi; Yamamoto, Tomonori; Fuke, Akihiro; Hashimoto, Atsunori; Koami, Hiroyuki; Beppu, Satoru; Katayama, Yoichi; Itoh, Makoto; Ohta, Yoshinori

    2017-01-01

    Importance Dexmedetomidine provides sedation for patients undergoing ventilation; however, its effects on mortality and ventilator-free days have not been well studied among patients with sepsis. Objectives To examine whether a sedation strategy with dexmedetomidine can improve clinical outcomes in patients with sepsis undergoing ventilation. Design, Setting, and Participants Open-label, multicenter randomized clinical trial conducted at 8 intensive care units in Japan from February 2013 until January 2016 among 201 consecutive adult patients with sepsis requiring mechanical ventilation for at least 24 hours. Interventions Patients were randomized to receive either sedation with dexmedetomidine (n = 100) or sedation without dexmedetomidine (control group; n = 101). Other agents used in both groups were fentanyl, propofol, and midazolam. Main Outcomes and Measures The co–primary outcomes were mortality and ventilator-free days (over a 28-day duration). Sequential Organ Failure Assessment score (days 1, 2, 4, 6, 8), sedation control, occurrence of delirium and coma, intensive care unit stay duration, renal function, inflammation, and nutrition state were assessed as secondary outcomes. Results Of the 203 screened patients, 201 were randomized. The mean age was 69 years (SD, 14 years); 63% were male. Mortality at 28 days was not significantly different in the dexmedetomidine group vs the control group (19 patients [22.8%] vs 28 patients [30.8%]; hazard ratio, 0.69; 95% CI, 0.38-1.22; P = .20). Ventilator-free days over 28 days were not significantly different between groups (dexmedetomidine group: median, 20 [interquartile range, 5-24] days; control group: median, 18 [interquartile range, 0.5-23] days; P = .20). The dexmedetomidine group had a significantly higher rate of well-controlled sedation during mechanical ventilation (range, 17%-58% vs 20%-39%; P = .01); other outcomes were not significantly different between groups. Adverse events

  16. Ventilation of the Subtropical North Atlantic: Locations and Times of Last Ventilation Estimated Using Tracer Constraints From GEOTRACES Section GA03

    NASA Astrophysics Data System (ADS)

    Holzer, Mark; Smethie, William M.; Ting, Yu-Heng

    2018-04-01

    The ventilation of the subtropical North Atlantic along GEOTRACES section GA03 is quantified in terms of where and how long ago water was last in the mixed layer. Measurements of T, S, PO4∗, CFC-11, CFC-12, SF6, and estimates of prebomb 14C are deconvolved for the boundary propagator G using a maximum-entropy approach. From G, we calculate the fractions of water last ventilated in specified surface regions Ωw. We estimate that (56 ± 13)% of the water deeper than 1,000 m was ventilated in northern high latitudes, (15 ± 5)% in the Mediterranean, and (27 ± 12)% in the Southern Ocean. Below the thermocline and outside the deep western boundary current, mean ages of Ωw-ventilated water exceed a century. Consequently, memory of where last ventilation occurred tends to get lost and the deep mean-age patterns of Ωw-ventilated water are broadly similar for all Ωw. The mean ventilation ages, averaged over the section with Ωw-fraction weights, are roughly 200 years for all deep water masses except for water last ventilated south of the Antarctic divergence, which is about twice as old. The uncertainties in the section-mean profiles of the Ωw fractions and their mean ages are ˜50% and ˜20%, respectively. The Ωw fractions have vertically diffuse overlapping patterns suggesting significant diapycnal mixing, consistent with century-scale mean ages. We quantify the seasonal cycle of ventilation and find that in both hemispheres peak ventilation occurs during late winter and early spring, but Northern Hemisphere ventilated deep waters have a more pronounced seasonal cycle with nearly zero summertime ventilation.

  17. 46 CFR 111.103-3 - Machinery space ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Machinery space ventilation. 111.103-3 Section 111.103-3...-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have two controls to stop the ventilation, one of which may be the supply...

  18. 46 CFR 111.103-3 - Machinery space ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Machinery space ventilation. 111.103-3 Section 111.103-3...-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have two controls to stop the ventilation, one of which may be the supply...

  19. 46 CFR 108.181 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Ventilation for enclosed spaces. 108.181 Section 108.181... AND EQUIPMENT Construction and Arrangement Ventilation § 108.181 Ventilation for enclosed spaces. (a) Each enclosed space must be vented or ventilated. (b) There must be a means to close each vent or...

  20. 46 CFR 108.181 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Ventilation for enclosed spaces. 108.181 Section 108.181... AND EQUIPMENT Construction and Arrangement Ventilation § 108.181 Ventilation for enclosed spaces. (a) Each enclosed space must be vented or ventilated. (b) There must be a means to close each vent or...

  1. 46 CFR 108.181 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Ventilation for enclosed spaces. 108.181 Section 108.181... AND EQUIPMENT Construction and Arrangement Ventilation § 108.181 Ventilation for enclosed spaces. (a) Each enclosed space must be vented or ventilated. (b) There must be a means to close each vent or...

  2. 46 CFR 111.103-3 - Machinery space ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Machinery space ventilation. 111.103-3 Section 111.103-3...-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have two controls to stop the ventilation, one of which may be the supply...

  3. 46 CFR 108.181 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Ventilation for enclosed spaces. 108.181 Section 108.181... AND EQUIPMENT Construction and Arrangement Ventilation § 108.181 Ventilation for enclosed spaces. (a) Each enclosed space must be vented or ventilated. (b) There must be a means to close each vent or...

  4. 46 CFR 111.103-3 - Machinery space ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Machinery space ventilation. 111.103-3 Section 111.103-3...-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have two controls to stop the ventilation, one of which may be the supply...

  5. 46 CFR 111.103-3 - Machinery space ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Machinery space ventilation. 111.103-3 Section 111.103-3...-GENERAL REQUIREMENTS Remote Stopping Systems § 111.103-3 Machinery space ventilation. (a) Each machinery space ventilation system must have two controls to stop the ventilation, one of which may be the supply...

  6. 46 CFR 108.181 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Ventilation for enclosed spaces. 108.181 Section 108.181... AND EQUIPMENT Construction and Arrangement Ventilation § 108.181 Ventilation for enclosed spaces. (a) Each enclosed space must be vented or ventilated. (b) There must be a means to close each vent or...

  7. Echocardiographic evaluation during weaning from mechanical ventilation.

    PubMed

    Schifelbain, Luciele Medianeira; Vieira, Silvia Regina Rios; Brauner, Janete Salles; Pacheco, Deise Mota; Naujorks, Alexandre Antonio

    2011-01-01

    Echocardiographic, electrocardiographic and other cardiorespiratory variables can change during weaning from mechanical ventilation. To analyze changes in cardiac function, using Doppler echocardiogram, in critical patients during weaning from mechanical ventilation, using two different weaning methods: pressure support ventilation and T-tube; and comparing patient subgroups: success vs. failure in weaning. Randomized crossover clinical trial including patients under mechanical ventilation for more than 48 h and considered ready for weaning. Cardiorespiratory variables, oxygenation, electrocardiogram and Doppler echocardiogram findings were analyzed at baseline and after 30 min in pressure support ventilation and T-tube. Pressure support ventilation vs. T-tube and weaning success vs. failure were compared using ANOVA and Student's t-test. The level of significance was p<0.05. Twenty-four adult patients were evaluated. Seven patients failed at the first weaning attempt. No echocardiographic or electrocardiographic differences were observed between pressure support ventilation and T-tube. Weaning failure patients presented increases in left atrium, intraventricular septum thickness, posterior wall thickness and diameter of left ventricle and shorter isovolumetric relaxation time. Successfully weaned patients had higher levels of oxygenation. No differences were observed between Doppler echocardiographic variables and electrocardiographic and other cardiorespiratory variables during pressure support ventilation and T-tube. However cardiac structures were smaller, isovolumetric relaxation time was larger, and oxygenation level was greater in successfully weaned patients.

  8. Echocardiographic evaluation during weaning from mechanical ventilation

    PubMed Central

    Schifelbain, Luciele Medianeira; Vieira, Silvia Regina Rios; Brauner, Janete Salles; Pacheco, Deise Mota; Naujorks, Alexandre Antonio

    2011-01-01

    INTRODUCTION: Echocardiographic, electrocardiographic and other cardiorespiratory variables can change during weaning from mechanical ventilation. OBJECTIVES: To analyze changes in cardiac function, using Doppler echocardiogram, in critical patients during weaning from mechanical ventilation, using two different weaning methods: pressure support ventilation and T‐tube; and comparing patient subgroups: success vs. failure in weaning. METHODS: Randomized crossover clinical trial including patients under mechanical ventilation for more than 48 h and considered ready for weaning. Cardiorespiratory variables, oxygenation, electrocardiogram and Doppler echocardiogram findings were analyzed at baseline and after 30 min in pressure support ventilation and T‐tube. Pressure support ventilation vs. T‐tube and weaning success vs. failure were compared using ANOVA and Student's t‐test. The level of significance was p<0.05. RESULTS: Twenty‐four adult patients were evaluated. Seven patients failed at the first weaning attempt. No echocardiographic or electrocardiographic differences were observed between pressure support ventilation and T‐tube. Weaning failure patients presented increases in left atrium, intraventricular septum thickness, posterior wall thickness and diameter of left ventricle and shorter isovolumetric relaxation time. Successfully weaned patients had higher levels of oxygenation. CONCLUSION: No differences were observed between Doppler echocardiographic variables and electrocardiographic and other cardiorespiratory variables during pressure support ventilation and T‐tube. However cardiac structures were smaller, isovolumetric relaxation time was larger, and oxygenation level was greater in successfully weaned patients. PMID:21437445

  9. Evolution of AF6-RAS association and its implications in mixed-lineage leukemia

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

    Smith, Matthew J.; Ottoni, Elizabeth; Ishiyama, Noboru

    Elucidation of activation mechanisms governing protein fusions is essential for therapeutic development. MLL undergoes rearrangement with numerous partners, including a recurrent translocation fusing the epigenetic regulator to a cytoplasmic RAS effector, AF6/afadin. We show here that AF6 employs a non-canonical, evolutionarily conserved α-helix to bind RAS, unique to AF6 and the classical RASSF effectors. Further, all patients with MLL-AF6 translocations express fusion proteins missing only this helix from AF6, resulting in exposure of hydrophobic residues that induce dimerization. We provide evidence that oligomerization is the dominant mechanism driving oncogenesis from rare MLL translocation partners and employ our mechanistic understanding ofmore » MLL-AF6 to examine how dimers induce leukemia. Proteomic data resolve association of dimerized MLL with gene expression modulators, and inhibiting dimerization disrupts formation of these complexes while completely abrogating leukemogenesis in mice. Oncogenic gene translocations are thus selected under pressure from protein structure/function, underscoring the complex nature of chromosomal rearrangements.« less

  10. Omnidirectional ventilated acoustic barrier

    NASA Astrophysics Data System (ADS)

    Zhang, Hai-long; Zhu, Yi-fan; Liang, Bin; Yang, Jing; Yang, Jun; Cheng, Jian-chun

    2017-11-01

    As an important problem in acoustics, sound insulation finds applications in a great variety of situations. In the existing schemes, however, there has always been a trade-off between the thinness of sound-insulating devices and their ventilating capabilities, limiting their potentials in the control of low-frequency sound in high ventilation environments. Here, we design and experimentally implement an omnidirectional acoustic barrier with a planar profile, subwavelength thickness ( 0.18 λ ), yet high ventilation. The proposed mechanism is based on the interference between the resonant scattering of discrete states and the background scattering of continuous states which induces a Fano-like asymmetric transmission profile. Benefitting from the binary-structured design of the coiled unit and hollow pipe, it maximally simplifies the design and fabrication while ensuring the ventilation for all the non-resonant units with open tubes. The simulated and measured results agree well, showing the effectiveness of our proposed mechanism to block low frequency sound coming from various directions while allowing 63% of the air flow to pass. We anticipate our design to open routes to design sound insulators and to enable applications in traditionally unattainable cases such as those calling for noise reduction and cooling simultaneously.

  11. Performance of Leak Compensation in All-Age ICU Ventilators During Volume-Targeted Neonatal Ventilation: A Lung Model Study.

    PubMed

    Itagaki, Taiga; Bennett, Desmond J; Chenelle, Christopher T; Fisher, Daniel F; Kacmarek, Robert M

    2017-01-01

    Volume-targeted ventilation is increasingly used in low birthweight infants because of the potential for reducing volutrauma and avoiding hypocapnea. However, it is not known what level of air leak is acceptable during neonatal volume-targeted ventilation when leak compensation is activated concurrently. Four ICU ventilators (Servo-i, PB980, V500, and Avea) were compared in available invasive volume-targeted ventilation modes (pressure control continuous spontaneous ventilation [PC-CSV] and pressure control continuous mandatory ventilation [PC-CMV]). The Servo-i and PB980 were tested with (+) and without (-) their proximal flow sensor. The V500 and Avea were tested with their proximal flow sensor as indicated by their manufacturers. An ASL 5000 lung model was used to simulate 4 neonatal scenarios (body weight 0.5, 1, 2, and 4 kg). The ASL 5000 was ventilated via an endotracheal tube with 3 different leaks. Two minutes of data were collected after each change in leak level, and the asynchrony index was calculated. Tidal volume (V T ) before and after the change in leak was assessed. The differences in delivered V T between before and after the change in leak were within ±5% in all scenarios with the PB980 (-/+) and V500. With the Servo-i (-/+), baseline V T was ≥10% greater than set V T during PC-CSV, and delivered V T markedly changed with leak. The Avea demonstrated persistent high V T in all leak scenarios. Across all ventilators, the median asynchrony index was 1% (interquartile range 0-27%) in PC-CSV and 1.8% (0-45%) in PC-CMV. The median asynchrony index was significantly higher in the Servo-i (-/+) than in the PB980 (-/+) and V500 in 1 and 2 kg scenarios during PC-CSV and PC-CMV. The PB980 and V500 were the only ventilators to acclimate to all leak scenarios and achieve targeted V T . Further clinical investigation is needed to validate the use of leak compensation during neonatal volume-targeted ventilation. Copyright © 2017 by Daedalus Enterprises.

  12. Automated ventilator testing.

    PubMed

    Ghaly, J; Smith, A L

    1994-06-01

    A new era has arrived for the Biomedical Engineering Department at the Royal Women's Hospital in Melbourne. We have developed a system to qualitatively test for intermittent or unconfirmed faults, associated with Bear Cub ventilators. Where previous testing has been inadequate, computer logging is now used to interface the RT200 Timeter Calibration Analyser (TCA) to obtain a real time display of data, which can be stored and graphed. Using Quick Basic version 4.5, it was possible to establish communication between the TCA and an IBM compatible computer, such that meaningful displays of machine performance were produced. From the parameters measured it has been possible to obtain data on Peak Pressure, Inspiratory to Expiratory ratio (I:E ratio) Peak Flow and Rate. Monitoring is not limited to these parameters, though these were selected for our particular needs. These parameters are plotted in two ways: 1. Compressed average versus time, up to 24 hours on one screen 2. Raw data, 36 minutes displayed on each screen. The compressed data gives an overview which allows easy identification of intermittent faults. The uncompressed data confirms that the averaged signal is a realistic representation of the situation. One of the major benefits of this type of data analysis, is that ventilator performance may be monitored over a long period of time without requiring the presence of a service technician. It also allows individual ventilator performance to be graphically compared to other ventilators.

  13. The Fluid Mechanics of Natural Ventilation

    NASA Astrophysics Data System (ADS)

    Linden, P. F.

    1999-01-01

    Natural ventilation of buildings is the flow generated by temperature differences and by the wind. The governing feature of this flow is the exchange between an interior space and the external ambient. Although the wind may often appear to be the dominant driving mechanism, in many circumstances temperature variations play a controlling feature on the ventilation since the directional buoyancy force has a large influence on the flow patterns within the space and on the nature of the exchange with the outside. Two forms of ventilation are discussed: mixing ventilation, in which the interior is at an approximately uniform temperature, and displacement ventilation, where there is strong internal stratification. The dynamics of these buoyancy-driven flows are considered, and the effects of wind on them are examined. The aim behind this work is to give designers rules and intuition on how air moves within a building; the research reveals a fascinating branch of fluid mechanics.

  14. Adaptive-servo ventilation combined with deep sedation is an effective strategy during pulmonary vein isolation.

    PubMed

    Murakami, Takashi; Yamaji, Hirosuke; Numa, Kenji; Kawamura, Hiroshi; Murakami, Masaaki; Higashiya, Shunichi; Kamikawa, Shigeshi; Hina, Kazuyoshi; Hirohata, Satoshi; Kusachi, Shozo

    2013-07-01

    Pulmonary vein isolation (PVI) by catheter ablation for atrial fibrillation (AF) requires suppression of patient restlessness by sufficient sedation in addition to maintaining stable respiration. We applied adaptive-servo ventilation (ASV) and examined the effects of ASV combined with deep propofol sedation on PVI using a NavX. We analysed 75 paroxysmal AF (PAF) patients (62 ± 11 years; 53 men and 22 women) who underwent PVI for treatment of PAF using an ASV system combined with deep sedation (ASV group). Control patients included 75 consecutive PAF patients (62 ± 11 years; 51 men and 24 women) who underwent PVI just before introduction of the ASV system. Deep sedation was defined as a Ramsay sedation score of 6. The ASV group had a lower frequency of restless body movements compared with the control group during PVI (1.5 ± 0.7 vs. 7.8 ± 1.4 times, P < 0.01). The frequency of respiratory compensation and EnGuide alignment of catheter position by the NavX was lower in the ASV (4.2 ± 3.3 and 8.8 ± 7.1 times) than control group (7.1 ± 5.1 and 15.2 ± 10.0 times, P < 0.05 and <0.01, respectively). Consequently, significantly lower total electrical energy supply (48.7 ± 6.0 KJ) was required in the ASV than control group (64.5 ± 24.9 KJ, P < 0.01). Further, significantly shorter fluoroscopy and procedural times were observed in the ASV (28 ± 5 and 109 ± 25 min) than the control group (33 ± 6 and 141 ± 38 min, respectively, P < 0.01) and the AF recurrence rate was significantly lower in the ASV than the control group (12 vs. 25%, P < 0.01). ASV combined with deep sedation is an effective strategy during PVI using the NavX in patients with PAF.

  15. 14 CFR 121.219 - Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Ventilation. 121.219 Section 121.219 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS... passenger or crew compartment must be suitably ventilated. Carbon monoxide concentration may not be more...

  16. The AFS Volunteer Resources Study: Summary of Findings from Australia.

    ERIC Educational Resources Information Center

    Walsh, Desmond; And Others

    The American Field Service (AFS) has 3,500 volunteers throughout Australia. Local chapters recruit potential host families and participants. Host families are recruited actively and selectively while volunteers are recruited largely through AFS presentations at schools, through friends, and by returning volunteers. Due to a high level of demand…

  17. 46 CFR 127.260 - Ventilation for accommodations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Ventilation for accommodations. 127.260 Section 127.260... ARRANGEMENTS Particular Construction and Arrangements § 127.260 Ventilation for accommodations. (a) Each... vessel of 100 or more gross tons must be provided with a mechanical ventilation system unless the...

  18. Natural ventilation for the prevention of airborne contagion.

    PubMed

    Escombe, A Roderick; Oeser, Clarissa C; Gilman, Robert H; Navincopa, Marcos; Ticona, Eduardo; Pan, William; Martínez, Carlos; Chacaltana, Jesus; Rodríguez, Richard; Moore, David A J; Friedland, Jon S; Evans, Carlton A

    2007-02-01

    Institutional transmission of airborne infections such as tuberculosis (TB) is an important public health problem, especially in resource-limited settings where protective measures such as negative-pressure isolation rooms are difficult to implement. Natural ventilation may offer a low-cost alternative. Our objective was to investigate the rates, determinants, and effects of natural ventilation in health care settings. The study was carried out in eight hospitals in Lima, Peru; five were hospitals of "old-fashioned" design built pre-1950, and three of "modern" design, built 1970-1990. In these hospitals 70 naturally ventilated clinical rooms where infectious patients are likely to be encountered were studied. These included respiratory isolation rooms, TB wards, respiratory wards, general medical wards, outpatient consulting rooms, waiting rooms, and emergency departments. These rooms were compared with 12 mechanically ventilated negative-pressure respiratory isolation rooms built post-2000. Ventilation was measured using a carbon dioxide tracer gas technique in 368 experiments. Architectural and environmental variables were measured. For each experiment, infection risk was estimated for TB exposure using the Wells-Riley model of airborne infection. We found that opening windows and doors provided median ventilation of 28 air changes/hour (ACH), more than double that of mechanically ventilated negative-pressure rooms ventilated at the 12 ACH recommended for high-risk areas, and 18 times that with windows and doors closed (p < 0.001). Facilities built more than 50 years ago, characterised by large windows and high ceilings, had greater ventilation than modern naturally ventilated rooms (40 versus 17 ACH; p < 0.001). Even within the lowest quartile of wind speeds, natural ventilation exceeded mechanical (p < 0.001). The Wells-Riley airborne infection model predicted that in mechanically ventilated rooms 39% of susceptible individuals would become infected following

  19. Characteristics of coal mine ventilation air flows.

    PubMed

    Su, Shi; Chen, Hongwei; Teakle, Philip; Xue, Sheng

    2008-01-01

    Coal mine methane (CMM) is not only a greenhouse gas but also a wasted energy resource if not utilised. Underground coal mining is by far the most important source of fugitive methane emissions, and approximately 70% of all coal mining related methane is emitted to the atmosphere through mine ventilation air. Therefore, research and development on mine methane mitigation and utilisation now focuses on methane emitted from underground coal mines, in particular ventilation air methane (VAM) capture and utilisation. To date, most work has focused on the oxidation of very low concentration methane. These processes may be classified based on their combustion kinetic mechanisms into thermal oxidation and catalytic oxidation. VAM mitigation/utilisation technologies are generally divided into two basic categories: ancillary uses and principal uses. However, it is possible that the characteristics of ventilation air flows, for example the variations in methane concentration and the presence of certain compounds, which have not been reported so far, could make some potential VAM mitigation and utilisation technologies unfeasible if they cannot cope with the characteristics of mine site ventilation air flows. Therefore, it is important to understand the characteristics of mine ventilation air flows. Moreover, dust, hydrogen sulphide, sulphur dioxide, and other possible compounds emitted through mine ventilation air into the atmosphere are also pollutants. Therefore, this paper presents mine-site experimental results on the characteristics of mine ventilation air flows, including methane concentration and its variations, dust loadings, particle size, mineral matter of the dust, and other compounds in the ventilation air flows. The paper also discusses possible correlations between ventilation air characteristics and underground mining activities.

  20. [Pediatric home ventilation--practical approach].

    PubMed

    Rath-Wacenovsky, Regina

    2015-09-01

    Out-of-hospital ventilation represents only a marginal area of paediatric therapeutic concepts. In Austria, the proportion of children to be supplied with invasive and non-invasive ventilation increases significantly, together with the challenges of caring for their long-term demands. Neuromuscular diseases accounted for almost the sole indication group. Premature and newborn infants with persistent respiratory failures are an increasing group, needing more extensive care due to additional comorbidities. Children with congenital disorder have often been tracheotomised in order to secure their airway, and non-invasive ventilation as a bridge- or long-term therapy gains in importance more and more. Usually, infants with primary or secondary CNS disorders suffer from respiratory complications and eventually from chronic respiratory insufficiencies during adolescence or young adulthood. Here, invasive or non-invasive ventilation can contribute both to a significant stabilisation of health status and also quality of life. Spirit of research, experience, appropriate support structures, and appropriate networking constitute the most relevant quality- and success criteria for home care.

  1. Effect of aldosterone on cochlear Af9 expression and hearing in guinea pig.

    PubMed

    Qin, Li; Zhang, Biyun; Wang, Qianying; Li, Duanchao; Luo, Xiaoli; Zhong, Shixun

    2017-09-01

    Af9 protein in cochlea may be closely related to endolymph regulation by aldosterone and thus may be involved in pathogenesis of endolymphatic hydrops (EH). EH is the pathological characteristic of Ménière's disease (MD). Aldosterone could induce EH, but its relationship with MD is still controversial. The aim of the present study is to investigate the Af9 protein expression in guinea pig cochlea and regulation of Af9 expression and cochlear function by aldosterone. The role of Af9 in pathogenesis of EH is discussed. Thirty guinea pigs were randomly divided into two groups. The treatment group was intraperitoneally injected with aldosterone 0.1 mg/kg/d for 5 days, while the control group was done with saline. Hearing and histomorphology of cochlea were examined. In addition, expression of Af9 protein was studied. The hearing threshold of the treatment group was increased. EH was induced in 73% of guinea pigs in the treatment group, and no EH was found in the control group. Af9 protein was found in spiral limbus, stria vascularis, Reissner's membrane, organ of Corti and spiral ganglion in both groups. Af9 expression in cochlea decreased significantly at protein level after treatment by aldosterone.

  2. GLA-AF, an emulsion-free vaccine adjuvant for pandemic influenza.

    PubMed

    Clegg, Christopher H; Roque, Richard; Perrone, Lucy A; Rininger, Joseph A; Bowen, Richard; Reed, Steven G

    2014-01-01

    The ongoing threat from Influenza necessitates the development of new vaccine and adjuvant technologies that can maximize vaccine immunogenicity, shorten production cycles, and increase global vaccine supply. Currently, the most successful adjuvants for Influenza vaccines are squalene-based oil-in-water emulsions. These adjuvants enhance seroprotective antibody titers to homologous and heterologous strains of virus, and augment a significant dose sparing activity that could improve vaccine manufacturing capacity. As an alternative to an emulsion, we tested a simple lipid-based aqueous formulation containing a synthetic TLR4 ligand (GLA-AF) for its ability to enhance protection against H5N1 infection. GLA-AF was very effective in adjuvanting recombinant H5 hemagglutinin antigen (rH5) in mice and was as potent as the stable emulsion, SE. Both adjuvants induced similar antibody titers using a sub-microgram dose of rH5, and both conferred complete protection against a highly pathogenic H5N1 challenge. However, GLA-AF was the superior adjuvant in ferrets. GLA-AF stimulated a broader antibody response than SE after both the prime and boost immunization with rH5, and ferrets were better protected against homologous and heterologous strains of H5N1 virus. Thus, GLA-AF is a potent emulsion-free adjuvant that warrants consideration for pandemic influenza vaccine development.

  3. Metabolically Derived Human Ventilation Rates: A Revised ...

    EPA Pesticide Factsheets

    EPA announced the availability of the final report, Metabolically Derived Human Ventilation Rates: A Revised Approach Based Upon Oxygen Consumption Rates. This report provides a revised approach for calculating an individual's ventilation rate directly from their oxygen consumption rate. This approach will be used to update the ventilation rate information in the Exposure Factors Handbook, which serve as a resources for exposure assessors for calculating inhalation and other exposures. In this report, EPA presents a revised approach in which ventilation rate is calculated directly from an individual's oxygen consumption rate.

  4. 46 CFR 194.15-5 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ....15-5 Ventilation. (a) Operations, reactions or experiments which produce toxic, noxious or corrosive...) Ventilation of air conditioning systems serving the chemical laboratory shall be designed so that air cannot...

  5. Implementation of a Goal-Directed Mechanical Ventilation Order Set Driven by Respiratory Therapists Improves Compliance With Best Practices for Mechanical Ventilation.

    PubMed

    Radosevich, Misty A; Wanta, Brendan T; Meyer, Todd J; Weber, Verlin W; Brown, Daniel R; Smischney, Nathan J; Diedrich, Daniel A

    2017-01-01

    Data regarding best practices for ventilator management strategies that improve outcomes in acute respiratory distress syndrome (ARDS) are readily available. However, little is known regarding processes to ensure compliance with these strategies. We developed a goal-directed mechanical ventilation order set that included physician-specified lung-protective ventilation and oxygenation goals to be implemented by respiratory therapists (RTs). We sought as a primary outcome to determine whether an RT-driven order set with predefined oxygenation and ventilation goals could be implemented and associated with improved adherence with best practice. We evaluated 1302 patients undergoing invasive mechanical ventilation (1693 separate episodes of invasive mechanical ventilation) prior to and after institution of a standardized, goal-directed mechanical ventilation order set using a controlled before-and-after study design. Patient-specific goals for oxygenation partial pressure of oxygen in arterial blood (Pao 2 ), ARDS Network [Net] positive end-expiratory pressure [PEEP]/fraction of inspired oxygen [Fio 2 ] table use) and ventilation (pH, partial pressure of carbon dioxide) were selected by prescribers and implemented by RTs. Compliance with the new mechanical ventilation order set was high: 88.2% compliance versus 3.8% before implementation of the order set ( P < .001). Adherence to the PEEP/Fio 2 table after implementation of the order set was significantly greater (86.0% after vs 82.9% before, P = .02). There was no difference in duration of mechanical ventilation, intensive care unit (ICU) length of stay, and in-hospital or ICU mortality. A standardized best practice mechanical ventilation order set can be implemented by a multidisciplinary team and is associated with improved compliance to written orders and adherence to the ARDSNet PEEP/Fio 2 table.

  6. 21 CFR 888.4230 - Cement ventilation tube.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Cement ventilation tube. 888.4230 Section 888.4230...) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4230 Cement ventilation tube. (a) Identification. A cement ventilation tube is a tube-like device usually made of plastic intended to be inserted into...

  7. 21 CFR 888.4230 - Cement ventilation tube.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cement ventilation tube. 888.4230 Section 888.4230...) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4230 Cement ventilation tube. (a) Identification. A cement ventilation tube is a tube-like device usually made of plastic intended to be inserted into...

  8. 21 CFR 888.4230 - Cement ventilation tube.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Cement ventilation tube. 888.4230 Section 888.4230...) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4230 Cement ventilation tube. (a) Identification. A cement ventilation tube is a tube-like device usually made of plastic intended to be inserted into...

  9. 21 CFR 888.4230 - Cement ventilation tube.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Cement ventilation tube. 888.4230 Section 888.4230...) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4230 Cement ventilation tube. (a) Identification. A cement ventilation tube is a tube-like device usually made of plastic intended to be inserted into...

  10. 21 CFR 888.4230 - Cement ventilation tube.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cement ventilation tube. 888.4230 Section 888.4230...) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4230 Cement ventilation tube. (a) Identification. A cement ventilation tube is a tube-like device usually made of plastic intended to be inserted into...

  11. Rivaroxaban in patients with atrial fibrillation: from ROCKET AF to everyday practice.

    PubMed

    Barón-Esquivias, Gonzalo; Marín, Francisco; Sanmartín Fernandez, Marcelo

    2017-05-01

    Registries and non-interventional studies offer relevant and complementary information to clinical trials, since they have a high external validity. Areas covered: The information regarding the efficacy and safety of rivaroxaban compared with warfarin, or rivaroxaban alone in clinical practice was reviewed in this manuscript. For this purpose, a search on MEDLINE and EMBASE databases was performed. The MEDLINE and EMBASE search included both medical subject headings (MeSH) and keywords including: atrial fibrillation (AF) OR warfarin OR clinical practice OR ROCKET AF AND rivaroxaban. Case reports were not considered. Expert commentary: In ROCKET AF, rivaroxaban was at least as effective as warfarin for the prevention of stroke in patients with nonvalvular AF at high risk of stroke, but, importantly, with a lesser risk of intracranial, critical and fatal bleedings. A number of observational comparative and non-comparative studies, with more than 60,000 patients included treated with rivaroxaban, have analyzed the efficacy and safety of rivaroxaban in real-life patients with AF in different clinical settings. These studies have shown that in clinical practice, rates of stroke and major bleeding were consistently lower than those reported in ROCKET AF, likely due to the lower thromboembolic and bleeding risk observed in these patients.

  12. GPIM AF-M315E Propulsion System

    NASA Technical Reports Server (NTRS)

    Spores, Ronald A.; Masse, Robert; Kimbrel, Scott; McLean, Chris

    2014-01-01

    The NASA Space Technology mission Directorate's (STMD) Green Propellant Infusion Mission (GPIM) Technology Demonstration Mission (TDM) will demonstrate an operational AF-M315E green propellant propulsion system. Aerojet-Rocketdyne is responsible for the development of the propulsion system payload. This paper statuses the propulsion system module development, including thruster design and system design; Initial test results for the 1N engineering model thruster are presented. The culmination of this program will be high-performance, green AF-M315E propulsion system technology at TRL 7+, with components demonstrated to TRL 9, ready for direct infusion to a wide range of applications for the space user community.

  13. A taxonomy for mechanical ventilation: 10 fundamental maxims.

    PubMed

    Chatburn, Robert L; El-Khatib, Mohamad; Mireles-Cabodevila, Eduardo

    2014-11-01

    The American Association for Respiratory Care has declared a benchmark for competency in mechanical ventilation that includes the ability to "apply to practice all ventilation modes currently available on all invasive and noninvasive mechanical ventilators." This level of competency presupposes the ability to identify, classify, compare, and contrast all modes of ventilation. Unfortunately, current educational paradigms do not supply the tools to achieve such goals. To fill this gap, we expand and refine a previously described taxonomy for classifying modes of ventilation and explain how it can be understood in terms of 10 fundamental constructs of ventilator technology: (1) defining a breath, (2) defining an assisted breath, (3) specifying the means of assisting breaths based on control variables specified by the equation of motion, (4) classifying breaths in terms of how inspiration is started and stopped, (5) identifying ventilator-initiated versus patient-initiated start and stop events, (6) defining spontaneous and mandatory breaths, (7) defining breath sequences (8), combining control variables and breath sequences into ventilatory patterns, (9) describing targeting schemes, and (10) constructing a formal taxonomy for modes of ventilation composed of control variable, breath sequence, and targeting schemes. Having established the theoretical basis of the taxonomy, we demonstrate a step-by-step procedure to classify any mode on any mechanical ventilator. Copyright © 2014 by Daedalus Enterprises.

  14. Thromboembolic event rate in paroxysmal and persistent atrial fibrillation: Data from the GISSI-AF trial

    PubMed Central

    2013-01-01

    Background Few data on the thromboembolic (TE) risk of paroxysmal and persistent atrial fibrillation (AF) are available. This study aimed to assess the incidence of TE events in paroxysmal and persistent AF. Methods We performed a subset post hoc analysis of 771 patients with paroxysmal and 463 with persistent AF enrolled in the multicenter, prospective, randomized, double-blind, placebo-controlled GISSI-AF trial - comparing the efficacy of valsartan versus placebo in preventing AF recurrences – where the choice of antithrombotic treatment was left to the judgment of the referring physician. TE and major outcome events were centrally validated. AF recurrences were detected by frequent clinic visits and a transtelephonic monitoring device with weekly and symptomatic transmissions. Results Eighty-five percent of patients had a history of hypertension, and the 7.7% had heart failure, left ventricular dysfunction, or both. The mean CHADS2 score was 1.41±0.84. TE and major bleeding events were observed at a low incidence among the overall population at 1-year follow-up (0.97% and 0.81%, respectively). The univariate and multivariable analyses revealed no statistically significant differences in the incidence of TE, major bleeding events or mortality in paroxysmal and persistent AF patients. TE events were more common among women than men (p=0.02). The follow-up examination showed under- or overtreatment with warfarin in many patients, according to guideline suggestions. Warfarin was more frequently prescribed to patients with persistent AF (p<0.0001) and patients with AF recurrences (p<0.0001). AF recurrences were noninvasively detected in 632 (51.2%) patients. In patients without AF recurrences, the TE event rate was 0.5% versus 1.74%, 1.28%, and 1.18% for those with only symptomatic, only asymptomatic or both symptomatic and asymptomatic AF recurrences, respectively, but the difference was not statistically significant, even after adjusting for warfarin treatment

  15. Management and outcome of mechanically ventilated neurologic patients.

    PubMed

    Pelosi, Paolo; Ferguson, Niall D; Frutos-Vivar, Fernando; Anzueto, Antonio; Putensen, Christian; Raymondos, Konstantinos; Apezteguia, Carlos; Desmery, Pablo; Hurtado, Javier; Abroug, Fekri; Elizalde, José; Tomicic, Vinko; Cakar, Nahit; Gonzalez, Marco; Arabi, Yaseen; Moreno, Rui; Esteban, Andres

    2011-06-01

    To describe and compare characteristics, ventilatory practices, and associated outcomes among mechanically ventilated patients with different types of brain injury and between neurologic and nonneurologic patients. Secondary analysis of a prospective, observational, and multicenter study on mechanical ventilation. Three hundred forty-nine intensive care units from 23 countries. We included 552 mechanically ventilated neurologic patients (362 patients with stroke and 190 patients with brain trauma). For comparison we used a control group of 4,030 mixed patients who were ventilated for nonneurologic reasons. None. We collected demographics, ventilatory settings, organ failures, and complications arising during ventilation and outcomes. Multivariate logistic regression analysis was performed with intensive care unit mortality as the dependent variable. At admission, a Glasgow Coma Scale score ≤8 was observed in 68% of the stroke, 77% of the brain trauma, and 29% of the nonneurologic patients. Modes of ventilation and use of a lung-protective strategy within the first week of mechanical ventilation were similar between groups. In comparison with nonneurologic patients, patients with neurologic disease developed fewer complications over the course of mechanical ventilation with the exception of a higher rate of ventilator-associated pneumonia in the brain trauma cohort. Neurologic patients showed higher rates of tracheotomy and longer duration of mechanical ventilation. Mortality in the intensive care unit was significantly (p < .001) higher in patients with stroke (45%) than in brain trauma (29%) and nonneurologic disease (30%). Factors associated with mortality were: stroke (in comparison to brain trauma), Glasgow Coma Scale score on day 1, and severity at admission in the intensive care unit. In our study, one of every five mechanically ventilated patients received this therapy as a result of a neurologic disease. This cohort of patients showed a higher mortality

  16. Analysis of a Pediatric Home Mechanical Ventilator Population.

    PubMed

    Amirnovin, Rambod; Aghamohammadi, Sara; Riley, Carley; Woo, Marlyn S; Del Castillo, Sylvia

    2018-05-01

    The population of children requiring home mechanical ventilation has evolved over the years and has grown to include a variety of diagnoses and needs that have led to changes in the care of this unique population. The purpose of this study was to provide a descriptive analysis of pediatric patients requiring home mechanical ventilation after hospitalization and how the evolution of this technology has impacted their care. A retrospective, observational, longitudinal analysis of 164 children enrolled in a university-affiliated home mechanical ventilation program over 26 years was performed. Data included each child's primary diagnosis, date of tracheostomy placement, duration of mechanical ventilation during hospitalization that consisted of home mechanical ventilator initiation, total length of pediatric ICU stay, ventilator settings at time of discharge from pediatric ICU, and disposition (home, facility, or died). Univariate, bivariate, and regression analysis was used as appropriate. The most common diagnosis requiring the use of home mechanical ventilation was neuromuscular disease (53%), followed by chronic pulmonary disease (29%). The median length of stay in the pediatric ICU decreased significantly after the implementation of a ventilator ward (70 d [30-142] vs 36 d [18-67], P = .02). The distribution of subjects upon discharge was home (71%), skilled nursing facility (24%), and died (4%), with an increase in the proportion of subjects discharged on PEEP and those going to nursing facilities over time ( P = 0.02). The evolution of home mechanical ventilation has allowed earlier transition out of the pediatric ICU and with increasing disposition to skilled nursing facilities over time. There has also been a change in ventilator management, including increased use of PEEP upon discharge, possibly driven by changes in ventilators and in-patient practice patterns. Copyright © 2018 by Daedalus Enterprises.

  17. Sustained Reduction of Ventilator-Associated Pneumonia Rates Using Real-Time Course Correction With a Ventilator Bundle Compliance Dashboard.

    PubMed

    Talbot, Thomas R; Carr, Devin; Parmley, C Lee; Martin, Barbara J; Gray, Barbara; Ambrose, Anna; Starmer, Jack

    2015-11-01

    The effectiveness of practice bundles on reducing ventilator-associated pneumonia (VAP) has been questioned. To implement a comprehensive program that included a real-time bundle compliance dashboard to improve compliance and reduce ventilator-associated complications. DESIGN Before-and-after quasi-experimental study with interrupted time-series analysis. SETTING Academic medical center. In 2007 a comprehensive institutional ventilator bundle program was developed. To assess bundle compliance and stimulate instant course correction of noncompliant parameters, a real-time computerized dashboard was developed. Program impact in 6 adult intensive care units (ICUs) was assessed. Bundle compliance was noted as an overall cumulative bundle adherence assessment, reflecting the percentage of time all elements were concurrently in compliance for all patients. The VAP rate in all ICUs combined decreased from 19.5 to 9.2 VAPs per 1,000 ventilator-days following program implementation (P<.001). Bundle compliance significantly increased (Z100 score of 23% in August 2007 to 83% in June 2011 [P<.001]). The implementation resulted in a significant monthly decrease in the overall ICU VAP rate of 3.28/1,000 ventilator-days (95% CI, 2.64-3.92/1,000 ventilator-days). Following the intervention, the VAP rate decreased significantly at a rate of 0.20/1,000 ventilator-days per month (95% CI, 0.14-0.30/1,000 ventilator-days per month). Among all adult ICUs combined, improved bundle compliance was moderately correlated with monthly VAP rate reductions (Pearson correlation coefficient, -0.32). A prevention program using a real-time bundle adherence dashboard was associated with significant sustained decreases in VAP rates and an increase in bundle compliance among adult ICU patients.

  18. Implementation of a real-time compliance dashboard to help reduce SICU ventilator-associated pneumonia with the ventilator bundle.

    PubMed

    Zaydfudim, Victor; Dossett, Lesly A; Starmer, John M; Arbogast, Patrick G; Feurer, Irene D; Ray, Wayne A; May, Addison K; Pinson, C Wright

    2009-07-01

    Ventilator-associated pneumonia (VAP) causes significant morbidity and mortality in critically ill surgical patients. Recent studies suggest that the success of preventive measures is dependent on compliance with ventilator bundle parameters. Implementation of an electronic dashboard will improve compliance with the bundle parameters and reduce rates of VAP in our surgical intensive care unit (SICU). Time series analysis of VAP rates between January 2005 and July 2008, with dashboard implementation in July 2007. Multidisciplinary SICU at a tertiary-care referral center with a stable case mix during the study period. Patients admitted to the SICU between January 2005 and July 2008. Infection control data were used to establish rates of VAP and total ventilator days. For the time series analysis, VAP rates were calculated as quarterly VAP events per 1000 ventilator days. Ventilator bundle compliance was analyzed after dashboard implementation. Differences between expected and observed VAP rates based on time series analysis were used to estimate the effect of intervention. Average compliance with the ventilator bundle improved from 39% in August 2007 to 89% in July 2008 (P < .001). Rates of VAP decreased from a mean (SD) of 15.2 (7.0) to 9.3 (4.9) events per 1000 ventilator days after introduction of the dashboard (P = .01). Quarterly VAP rates were significantly reduced in the November 2007 through January 2008 and February through April 2008 periods (P < .05). For the August through October 2007 and May through July 2008 quarters, the observed rate reduction was not statistically significant. Implementation of an electronic dashboard improved compliance with ventilator bundle measures and is associated with reduced rates of VAP in our SICU.

  19. Modes of mechanical ventilation for the operating room.

    PubMed

    Ball, Lorenzo; Dameri, Maddalena; Pelosi, Paolo

    2015-09-01

    Most patients undergoing surgical procedures need to be mechanically ventilated, because of the impact of several drugs administered at induction and during maintenance of general anaesthesia on respiratory function. Optimization of intraoperative mechanical ventilation can reduce the incidence of post-operative pulmonary complications and improve the patient's outcome. Preoxygenation at induction of general anaesthesia prolongs the time window for safe intubation, reducing the risk of hypoxia and overweighs the potential risk of reabsorption atelectasis. Non-invasive positive pressure ventilation delivered through different interfaces should be considered at the induction of anaesthesia morbidly obese patients. Anaesthesia ventilators are becoming increasingly sophisticated, integrating many functions that were once exclusive to intensive care. Modern anaesthesia machines provide high performances in delivering the desired volumes and pressures accurately and precisely, including assisted ventilation modes. Therefore, the physicians should be familiar with the potential and pitfalls of the most commonly used intraoperative ventilation modes: volume-controlled, pressure-controlled, dual-controlled and assisted ventilation. Although there is no clear evidence to support the advantage of any one of these ventilation modes over the others, protective mechanical ventilation with low tidal volume and low levels of positive end-expiratory pressure (PEEP) should be considered in patients undergoing surgery. The target tidal volume should be calculated based on the predicted or ideal body weight rather than on the actual body weight. To optimize ventilation monitoring, anaesthesia machines should include end-inspiratory and end-expiratory pause as well as flow-volume loop curves. The routine administration of high PEEP levels should be avoided, as this may lead to haemodynamic impairment and fluid overload. Higher PEEP might be considered during surgery longer than 3 h

  20. Transpleural ventilation of explanted human lungs

    PubMed Central

    Choong, Cliff K; Macklem, Peter T; Pierce, John A; Lefrak, Stephen S; Woods, Jason C; Conradi, Mark S; Yablonskiy, Dimitry A; Hogg, James C; Chino, Kimiaki; Cooper, Joel D

    2007-01-01

    Background The hypothesis that ventilation of emphysematous lungs would be enhanced by communication with the parenchyma through holes in the pleural surface was tested. Methods Fresh human lungs were obtained from patients with emphysema undergoing lung transplantation. Control human lungs were obtained from organ donors whose lungs, for technical reasons, were not considered suitable for implantation. Lungs were ventilated through the bronchial tree or transpleurally via a small hole communicating with the underlying parenchyma over which a flanged silicone tube had been cemented to the surface of the lung (spiracle). Measurements included flow‐volume‐time curves during passive deflation via each pathway; volume of trapped gas recovered from lungs via spiracles when no additional gas was obtainable passively from the airways; and magnetic resonance imaging assessment of spatial distribution of hyperpolarised helium (3He) administered through either the airways or spiracles. Results In emphysematous lungs, passively expelled volumes at 20 s were 94% greater through spiracles than via the airways. Following passive deflation from the airways, an average of 1.07 litres of trapped gas volume was recoverable via spiracles. Regions were ventilated by spiracles that were less well ventilated via bronchi. Conclusions Because of the extensive collateral ventilation present in emphysematous lungs, direct communication with the lung parenchyma through non‐anatomical pathways has the potential to improve the mechanics of breathing and hence ventilation. PMID:17412776

  1. Action of AF64A on rat brain muscarinic receptors

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

    Eva, C.; Costa, E.

    ICV administration of compound AF64A (ethylcholine mustard aziridium ion) induces a long-term selective cholinergic hypofunction; however, it does not modify the characteristics of muscarinic receptors. In brain muscarinic receptor activation can either stimulate phosphoinositide turnover or inhibit adenylate cyclase. ICV infusion of AF64A (5 nmol/side/2.5 ..mu..l) reduced the hippocampal ACh content 10 or 30 days after the treatment to 75% of the control values. Under these conditions neither in the striatum nor in the frontal cortex ACh levels were decreased. The carbachol dose-dependent stimulation in hippocampal slices differed from that observed in control rats. The carbachol efficacy was increased butmore » its potency was unchanged by AF64A. In contrast, ICV administration of AF64A failed to alter the oxotremorine efficacy or potency in inhibiting the forskolin stimulated adenylate cyclase in rat hippocampal membranes. These results suggest the two transducer systems coupled to muscarinic receptors may be differentially regulatable by cholinergic input.« less

  2. Clinical presentation, management, and outcomes in the Indian Heart Rhythm Society-Atrial Fibrillation (IHRS-AF) registry.

    PubMed

    Vora, A; Kapoor, A; Nair, M; Lokhandwala, Y; Narsimhan, C; Ravikishore, A G; Dwivedi, S K; Namboodiri, N; Hygriv, R; Saxena, A; Nabar, A; Garg, S; Bardoloi, N; Yadav, R; Nambiar, A; Pandurangi, U; Jhala, D; Naik, A; Nagmallesh; Rajagopal, S; Selvaraj, R; Arora, V; Thachil, A; Thomas, J; Panicker, G

    A national atrial fibrillation (AF) registry was conducted under the aegis of the Indian Heart Rhythm Society (IHRS), to capture epidemiological data-type of AF, clinical presentation and comorbidities, current treatment practices, and 1-year follow-up outcomes. A total of 1537 patients were enrolled from 24 sites in India in the IHRS-AF registry from July 2011 to August 2012. Their baseline characteristics and follow-up data were recorded in case report forms and subsequently analyzed. The average age of Indian AF patients was 54.7 years. There was a marginal female preponderance - 51.5% females and 48.5% males. At baseline, 20.4% had paroxysmal AF; 33% had persistent AF; 35.1% had permanent AF and 11% had first AF episode. At one-year follow-up, 45.6% patients had permanent AF. Rheumatic valvular heart disease (RHD) was present in 47.6% of patients. Hypertension, heart failure, coronary artery disease, and diabetes were seen in 31.4%, 18.7%, 16.2%, and 16.1%, respectively. Rate control was the strategy used in 75.2% patients, digoxin and beta-blockers being the most frequently prescribed rate-control drugs. Oral anticoagulation (OAC) drugs were used in 70% of patients. The annual mortality was 6.5%, hospitalization 8%, and incidence of stroke 1%. In India, AF patients are younger and RHD is still the most frequent etiology. Almost two-third of the patients have persistent/permanent AF. At one-year follow-up, there is a significant mortality and morbidity in AF patients in India. Copyright © 2016. Published by Elsevier B.V.

  3. Intraoperative mechanical ventilation: state of the art.

    PubMed

    Ball, Lorenzo; Costantino, Federico; Orefice, Giulia; Chandrapatham, Karthikka; Pelosi, Paolo

    2017-10-01

    Mechanical ventilation is a cornerstone of the intraoperative management of the surgical patient and is still mandatory in several surgical procedures. In the last decades, research focused on preventing postoperative pulmonary complications (PPCs), both improving risk stratification through the use of predictive scores and protecting the lung adopting so-called protective ventilation strategies. The aim of this review was to give an up-to-date overview of the currently suggested intraoperative ventilation strategies, along with their pathophysiologic rationale, with a focus on challenging conditions, such as obesity, one-lung ventilation and cardiopulmonary bypass. While anesthesia and mechanical ventilation are becoming increasingly safe practices, the contribution to surgical mortality attributable to postoperative lung injury is not negligible: for these reasons, the prevention of PPCs, including the use of protective mechanical ventilation is mandatory. Mechanical ventilation should be optimized providing an adequate respiratory support while minimizing unwanted negative effects. Due to the high number of surgical procedures performed daily, the impact on patients' health and healthcare costs can be relevant, even when new strategies result in an apparently small improvement of outcome. A protective intraoperative ventilation should include a low tidal volume of 6-8 mL/kg of predicted body weight, plateau pressures ideally below 16 cmH2O, the lowest possible driving pressure, moderate-low PEEP levels except in obese patients, laparoscopy and long surgical procedures that might benefit of a slightly higher PEEP. The work of the anesthesiologist should start with a careful preoperative visit to assess the risk, and a close postoperative monitoring.

  4. Perioperative lung protective ventilation in obese patients.

    PubMed

    Fernandez-Bustamante, Ana; Hashimoto, Soshi; Serpa Neto, Ary; Moine, Pierre; Vidal Melo, Marcos F; Repine, John E

    2015-05-06

    The perioperative use and relevance of protective ventilation in surgical patients is being increasingly recognized. Obesity poses particular challenges to adequate mechanical ventilation in addition to surgical constraints, primarily by restricted lung mechanics due to excessive adiposity, frequent respiratory comorbidities (i.e. sleep apnea, asthma), and concerns of postoperative respiratory depression and other pulmonary complications. The number of surgical patients with obesity is increasing, and facing these challenges is common in the operating rooms and critical care units worldwide. In this review we summarize the existing literature which supports the following recommendations for the perioperative ventilation in obese patients: (1) the use of protective ventilation with low tidal volumes (approximately 8 mL/kg, calculated based on predicted -not actual- body weight) to avoid volutrauma; (2) a focus on lung recruitment by utilizing PEEP (8-15 cmH2O) in addition to recruitment maneuvers during the intraoperative period, as well as incentivized deep breathing and noninvasive ventilation early in the postoperative period, to avoid atelectasis, hypoxemia and atelectrauma; and (3) a judicious oxygen use (ideally less than 0.8) to avoid hypoxemia but also possible reabsorption atelectasis. Obesity poses an additional challenge for achieving adequate protective ventilation during one-lung ventilation, but different lung isolation techniques have been adequately performed in obese patients by experienced providers. Postoperative efforts should be directed to avoid hypoventilation, atelectasis and hypoxemia. Further studies are needed to better define optimum protective ventilation strategies and analyze their impact on the perioperative outcomes of surgical patients with obesity.

  5. A historical perspective on ventilator management.

    PubMed

    Shapiro, B A

    1994-02-01

    Paralysis via neuromuscular blockade in ICU patients requires mechanical ventilation. This review historically addresses the technological advances and scientific information upon which ventilatory management concepts are based, with special emphasis on the influence such concepts have had on the use of neuromuscular blocking agents. Specific reference is made to the scientific information and technological advances leading to the newer concepts of ventilatory management. Information from > 100 major studies in the peer-reviewed medical literature, along with the author's 25 yrs of clinical experience and academic involvement in acute respiratory care is presented. Nomenclature related to ventilatory management is specifically defined and consistently utilized to present and interpret the data. Pre-1970 ventilatory management is traced from the clinically unacceptable pressure-limited devices to the reliable performance of volume-limited ventilators. The scientific data and rationale that led to the concept of relatively large tidal volume delivery are reviewed in the light of today's concerns regarding alveolar overdistention, control-mode dyssynchrony, and auto-positive end-expiratory pressure. Also presented are the post-1970 scientific rationales for continuous positive airway pressure/positive end-expiratory pressure therapy, avoidance of alveolar hyperxia, and partial ventilatory support techniques (intermittent mandatory ventilation/synchronized intermittent mandatory ventilation). The development of pressure-support devices is discussed and the capability of pressure-control techniques is presented. The rationale for more recent concepts of total ventilatory support to avoid ventilator-induced lung injury is presented. The traditional techniques utilizing volume-preset ventilators with relatively large tidal volumes remain valid and desirable for the vast majority of patients requiring mechanical ventilation. Neuromuscular blockade is best avoided in these

  6. The Bcr Kinase Downregulates Ras Signaling by Phosphorylating AF-6 and Binding to Its PDZ Domain

    PubMed Central

    Radziwill, G.; Erdmann, R. A.; Margelisch, U.; Moelling, K.

    2003-01-01

    The protein kinase Bcr is a negative regulator of cell proliferation and oncogenic transformation. We identified Bcr as a ligand for the PDZ domain of the cell junction and Ras-interacting protein AF-6. The Bcr kinase phosphorylates AF-6, which subsequently allows efficient binding of Bcr to AF-6, showing that the Bcr kinase is a regulator of the PDZ domain-ligand interaction. Bcr and AF-6 colocalize in epithelial cells at the plasma membrane. In addition, Bcr, AF-6, and Ras form a trimeric complex. Bcr increases the affinity of AF-6 to Ras, and a mutant of AF-6 that lacks a specific phosphorylation site for Bcr shows a reduced binding to Ras. Wild-type Bcr, but not Bcr mutants defective in binding to AF-6, interferes with the Ras-dependent stimulation of the Raf/MEK/ERK pathway. Since AF-6 binds to Bcr via its PDZ domain and to Ras via its Ras-binding domain, we propose that AF-6 functions as a scaffold-like protein that links Bcr and Ras to cellular junctions. We suggest that this trimeric complex is involved in downregulation of Ras-mediated signaling at sites of cell-cell contact to maintain cells in a nonproliferating state. PMID:12808105

  7. Respirator triggering of electron-beam computed tomography (EBCT): differences in dynamic changes between augmented ventilation and controlled mechanical ventilation

    NASA Astrophysics Data System (ADS)

    Recheis, Wolfgang A.; Kleinsasser, Axel; Schuster, Antonius H.; Loeckinger, Alexander; Frede, Thomas; Springer, Peter; Hoermann, Christoph; zur Nedden, Dieter

    2000-04-01

    The purpose was to evaluate differences in dynamic changes of the lung aeration (air-tissue ratio) between augmented modes of ventilation (AMV) and controlled mechanical ventilation (CMV) in normal subjects. 4 volunteers, ventilated with the different respirator protocols via face mask, were scanned using the EBCT in the 50 ms mode. A software analyzed the respirator's digitized pressure and volume signals of two subsequent ventilation phases. Using these values it was possible to calculate the onset of inspiration or expiration of the next respiratory phase. The calculated starting point was then used to trigger the EBCT. The dynamic changes of air- tissue ratios were evaluated in three separate regions: a ventral, an intermediate and a dorsal area. AMV results in increase of air-tissue ratio in the dorsal lung area due to the active contraction of the diaphragm, whereas CMV results in a more pronounced increase in air-tissue ratio of the ventral lung area. This study gives further insight into the dynamic changes of the lung's biomechanics by comparing augmented ventilation and controlled mechanical ventilation in the healthy proband.

  8. Effect of frequency of ventilator circuit changes (3 vs 7 days) on the rate of ventilator-associated pneumonia in PICU.

    PubMed

    Samransamruajkit, Rujipat; Jirapaiboonsuk, Suree; Siritantiwat, Sirirush; Tungsrijitdee, Ornanong; Deerojanawong, Jitladda; Sritippayawan, Suchada; Prapphal, Nuanchan

    2010-03-01

    Ventilator-associated pneumonia (VAP) is associated with significant morbidity and mortality in pediatric intensive care unit (PICU). Our purpose was to evaluate the effects of ventilator circuit change on the rate of VAP in the PICU. A prospective randomized controlled trial was conducted at a university hospital PICU. Children (younger than 18 years) who received mechanical ventilation from December 2006 to November 2007 were randomly assigned to receive ventilator circuit changes every 3 or 7 days. Of 176 patients, 88 were assigned to receive ventilator circuit every 3 days and 88 patients had a change weekly. The rate of VAP was 13.9/1000 ventilator days for the 3-day circuit change (n = 12) vs 11.5/1000 ventilator days (n = 10) for the 7-day circuit change (odds ratio, 0.8; confidence interval, 0.3-1.9; P = .6). There was a trend toward decreased PICU stay and mortality rate in 7-day change group compared to 3-day change group but did not reach statistical significance. Furthermore, switching from a 3-day to a 7-day change policy could save costs up to US $22,000/y. The 7-day ventilator circuit change did not contribute to increased rates of VAP in our PICU. Thus, it may be used as a guide to save workload and supply costs. Crown Copyright 2010. Published by Elsevier Inc. All rights reserved.

  9. Humidification during invasive and noninvasive mechanical ventilation: 2012.

    PubMed

    Restrepo, Ruben D; Walsh, Brian K

    2012-05-01

    We searched the MEDLINE, CINAHL, and Cochrane Library databases for articles published between January 1990 and December 2011. The update of this clinical practice guideline is based on 184 clinical trials and systematic reviews, and 10 articles investigating humidification during invasive and noninvasive mechanical ventilation. The following recommendations are made following the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) scoring system: 1. Humidification is recommended on every patient receiving invasive mechanical ventilation. 2. Active humidification is suggested for noninvasive mechanical ventilation, as it may improve adherence and comfort. 3. When providing active humidification to patients who are invasively ventilated, it is suggested that the device provide a humidity level between 33 mg H(2)O/L and 44 mg H(2)O/L and gas temperature between 34°C and 41°C at the circuit Y-piece, with a relative humidity of 100%. 4. When providing passive humidification to patients undergoing invasive mechanical ventilation, it is suggested that the HME provide a minimum of 30 mg H(2)O/L. 5. Passive humidification is not recommended for noninvasive mechanical ventilation. 6. When providing humidification to patients with low tidal volumes, such as when lung-protective ventilation strategies are used, HMEs are not recommended because they contribute additional dead space, which can increase the ventilation requirement and P(aCO(2)). 7. It is suggested that HMEs are not used as a prevention strategy for ventilator-associated pneumonia.

  10. Household ventilation and tuberculosis transmission in Kampala, Uganda.

    PubMed

    Chamie, G; Wandera, B; Luetkemeyer, A; Bogere, J; Mugerwa, R D; Havlir, D V; Charlebois, E D

    2013-06-01

    To test the feasibility of measuring household ventilation and evaluate whether ventilation is associated with tuberculosis (TB) in household contacts in Kampala, Uganda. Adults with pulmonary TB and their household contacts received home visits to ascertain social and structural household characteristics. Ventilation was measured in air changes per hour (ACH) in each room by raising carbon dioxide (CO₂) levels using dry ice, removing the dry ice, and measuring changes in the natural log of CO₂ (lnCO2) over time. Ventilation was compared in homes with and without co-prevalent TB. Members of 61 of 66 (92%) households approached were enrolled. Households averaged 5.4 residents/home, with a median of one room/home. Twelve homes (20%) reported co-prevalent TB in household contacts. Median ventilation for all rooms was 14 ACH (interquartile range [IQR] 10-18). Median ventilation was 12 vs. 15 ACH in index cases' sleeping rooms in households with vs. those without co-prevalent TB (P = 0.12). Among smear-positive indexes not infected by the human immunodeficiency virus (HIV), median ventilation was 11 vs. 17 ACH in index cases' sleeping rooms in homes with vs. those without co-prevalent TB (P = 0.1). Our findings provide evidence that a simple CO₂ decay method used to measure ventilation in clinical settings can be adapted to homes, adding a novel tool and a neglected variable, ventilation, to the study of household TB transmission.

  11. Are we fully utilizing the functionalities of modern operating room ventilators?

    PubMed

    Liu, Shujie; Kacmarek, Robert M; Oto, Jun

    2017-12-01

    The modern operating room ventilators have become very sophisticated and many of their features are comparable with those of an ICU ventilator. To fully utilize the functionality of modern operating room ventilators, it is important for clinicians to understand in depth the working principle of these ventilators and their functionalities. Piston ventilators have the advantages of delivering accurate tidal volume and certain flow compensation functions. Turbine ventilators have great ability of flow compensation. Ventilation modes are mainly volume-based or pressure-based. Pressure-based ventilation modes provide better leak compensation than volume-based. The integration of advanced flow generation systems and ventilation modes of the modern operating room ventilators enables clinicians to provide both invasive and noninvasive ventilation in perioperative settings. Ventilator waveforms can be used for intraoperative neuromonitoring during cervical spine surgery. The increase in number of new features of modern operating room ventilators clearly creates the opportunity for clinicians to optimize ventilatory care. However, improving the quality of ventilator care relies on a complete understanding and correct use of these new features. VIDEO ABSTRACT: http://links.lww.com/COAN/A47.

  12. Mechanical ventilation during extracorporeal membrane oxygenation. An international survey.

    PubMed

    Marhong, Jonathan D; Telesnicki, Teagan; Munshi, Laveena; Del Sorbo, Lorenzo; Detsky, Michael; Fan, Eddy

    2014-07-01

    In patients with severe, acute respiratory failure undergoing venovenous extracorporeal membrane oxygenation (VV-ECMO), the optimal strategy for mechanical ventilation is unclear. Our objective was to describe ventilation practices used in centers registered with the Extracorporeal Life Support Organization (ELSO). We conducted an international cross-sectional survey of medical directors and ECMO program coordinators from all ELSO-registered centers. The survey was distributed using a commercial website that collected information on center characteristics, the presence of a mechanical ventilator protocol, ventilator settings, and weaning practices. E-mails were sent out to medical directors or coordinators at each ELSO center and their responses were pooled for analysis. We analyzed 141 (50%) individual responses from the 283 centers contacted across 28 countries. Only 27% of centers reported having an explicit mechanical ventilation protocol for ECMO patients. The majority of these centers (77%) reported "lung rest" to be the primary goal of mechanical ventilation, whereas 9% reported "lung recruitment" to be their ventilation strategy. A tidal volume of 6 ml/kg or less was targeted by 76% of respondents, and 58% targeted a positive end-expiratory pressure of 6-10 cm H2O while ventilating patients on VV-ECMO. Centers prioritized weaning VV-ECMO before mechanical ventilation. Although ventilation practices in patients supported by VV-ECMO vary across ELSO centers internationally, the majority of centers used a strategy that targeted lung-protective thresholds and prioritized weaning VV-ECMO over mechanical ventilation.

  13. Conservative fluid management prevents age-associated ventilator induced mortality.

    PubMed

    Herbert, Joseph A; Valentine, Michael S; Saravanan, Nivi; Schneck, Matthew B; Pidaparti, Ramana; Fowler, Alpha A; Reynolds, Angela M; Heise, Rebecca L

    2016-08-01

    Approximately 800 thousand patients require mechanical ventilation in the United States annually with an in-hospital mortality rate of over 30%. The majority of patients requiring mechanical ventilation are over the age of 65 and advanced age is known to increase the severity of ventilator-induced lung injury (VILI) and in-hospital mortality rates. However, the mechanisms which predispose aging ventilator patients to increased mortality rates are not fully understood. Ventilation with conservative fluid management decreases mortality rates in acute respiratory distress patients, but to date there has been no investigation of the effect of conservative fluid management on VILI and ventilator associated mortality rates. We hypothesized that age-associated increases in susceptibility and incidence of pulmonary edema strongly promote age-related increases in ventilator associated mortality. 2month old and 20month old male C57BL6 mice were mechanically ventilated with either high tidal volume (HVT) or low tidal volume (LVT) for up to 4h with either liberal or conservative fluid support. During ventilation, lung compliance, total lung capacity, and hysteresis curves were quantified. Following ventilation, bronchoalveolar lavage fluid was analyzed for total protein content and inflammatory cell infiltration. Wet to dry ratios were used to directly measure edema in excised lungs. Lung histology was performed to quantify alveolar barrier damage/destruction. Age matched non-ventilated mice were used as controls. At 4h, both advanced age and HVT ventilation significantly increased markers of inflammation and injury, degraded pulmonary mechanics, and decreased survival rates. Conservative fluid support significantly diminished pulmonary edema and improved pulmonary mechanics by 1h in advanced age HVT subjects. In 4h ventilations, conservative fluid support significantly diminished pulmonary edema, improved lung mechanics, and resulted in significantly lower mortality rates in

  14. Conservative Fluid Management Prevents Age-Associated Ventilator Induced Mortality

    PubMed Central

    Herbert, Joseph A.; Valentine, Michael S.; Saravanan, Nivi; Schneck, Matthew B.; Pidaparti, Ramana; Fowler, Alpha A.; Reynolds, Angela M.; Heise, Rebecca L.

    2017-01-01

    Background Approximately 800 thousand patients require mechanical ventilation in the United States annually with an in-hospital mortality rate of over 30%. The majority of patients requiring mechanical ventilation are over the age of 65 and advanced age is known to increase the severity of ventilator-induced lung injury (VILI) and in-hosptial mortality rates. However, the mechanisms which predispose aging ventilator patients to increased mortality rates are not fully understood. Ventilation with conservative fluid management decreases mortality rates in acute respiratory distress patients, but to date there has been no investigation of the effect of conservative fluid management on VILI and ventilator associated mortality rates. We hypothesized that age-associated increases in susceptibility and incidence of pulmonary edema strongly promote age-related increases in ventilator associated mortality. Methods 2 month old and 20 month old male C57BL6 mice were mechanically ventilated with either high tidal volume (HVT) or low tidal volume (LVT) for up to 4 hours with either liberal or conservative fluid support. During ventilation, lung compliance, total lung capacity, and hysteresis curves were quantified. Following ventilation, bronchoalveolar lavage fluid was analyzed for total protein content and inflammatory cell infiltration. Wet to dry ratios were used to directly measure edema in excised lungs. Lung histology was performed to quantify alveolar barrier damage/destruction. Age matched non-ventilated mice were used as controls. Results At 4hrs, both advanced age and HVT ventilation significantly increased markers of inflammation and injury, degraded pulmonary mechanics, and decreased survival rates. Conservative fluid support significantly diminished pulmonary edema and improved pulmonary mechanics by 1hr in advanced age HVT subjects. In 4hr ventilations, conservative fluid support significantly diminished pulmonary edema, improved lung mechanics, and resulted in

  15. Atrial Fibrillation Management Strategies in Routine Clinical Practice: Insights from the International RealiseAF Survey

    PubMed Central

    Chiang, Chern-En; Naditch-Brûlé, Lisa; Brette, Sandrine; Silva-Cardoso, José; Gamra, Habib; Murin, Jan; Zharinov, Oleg J.; Steg, Philippe Gabriel

    2016-01-01

    Background Atrial fibrillation (AF) can be managed with rhythm- or rate-control strategies. There are few data from routine clinical practice on the frequency with which each strategy is used and their correlates in terms of patients’ clinical characteristics, AF control, and symptom burden. Methods RealiseAF was an international, cross-sectional, observational survey of 11,198 patients with AF. The aim of this analysis was to describe patient profiles and symptoms according to the AF management strategy used. A multivariate logistic regression identified factors associated with AF management strategy at the end of the visit. Results Among 10,497 eligible patients, 53.7% used a rate-control strategy, compared with 34.5% who used a rhythm-control strategy. In 11.8% of patients, no clear strategy was stated. The proportion of patients with AF-related symptoms (EHRA Class > = II) was 78.1% (n = 4396/5630) for those using a rate-control strategy vs. 67.8% for those using a rhythm-control strategy (p<0.001). Multivariate logistic regression analysis revealed that age <75 years or the paroxysmal or persistent form of AF favored the choice of a rhythm-control strategy. A change in strategy was infrequent, even in patients with European Heart Rhythm Association (EHRA) Class > = II. Conclusions In the RealiseAF routine clinical practice survey, rate control was more commonly used than rhythm control, and a change in strategy was uncommon, even in symptomatic patients. In almost 12% of patients, no clear strategy was stated. Physician awareness regarding optimal management strategies for AF may be improved. PMID:26800084

  16. Ventilator-associated pneumonia management in critical illness.

    PubMed

    Albertos, Raquel; Caralt, Berta; Rello, Jordi

    2011-03-01

    Ventilator-associated pneumonia (VAP) is a frequent adverse event in the intensive care unit.We review recent publications about the management and prevention of VAP. The latest care bundles introduced standard interventions to facilitate implementation of evidence-based clinical guidelines and to improve the outcome of patients. Recent studies find that prevention management of ventilated patients decreases the risk of VAP. Enteral feeding, considered a risk factor for VAP, currently has been recommended, with appropriate administration, for all critical ill patients if no contraindications exist. In view of the recently available data, it can be concluded that the implementation of care bundles on the general management of ventilated patients in daily practice has reduced the VAP rates. The main pharmacological measures to prevent VAP are proper hands hygiene, high nurse-to-patient ratio, avoid unnecessary transfer of ventilated patients, use of noninvasive mechanical ventilation, shortening weaning period, avoid the use of nasal intubation, prevent bio-film deposition in endotracheal tube, aspiration of subglottic secretions, maintenance of adequate pressure of endotracheal cuffs, avoid manipulation of ventilator circuits, semi-recumbent position and adequate enteral feeding.In addition, updated guidelines incorporate more comprehensive diagnostic protocols to the evidence-based management of VAP.

  17. Delivery of tidal volume from four anaesthesia ventilators during volume-controlled ventilation: a bench study.

    PubMed

    Wallon, G; Bonnet, A; Guérin, C

    2013-06-01

    Tidal volume (V(T)) must be accurately delivered by anaesthesia ventilators in the volume-controlled ventilation mode in order for lung protective ventilation to be effective. However, the impact of fresh gas flow (FGF) and lung mechanics on delivery of V(T) by the newest anaesthesia ventilators has not been reported. We measured delivered V(T) (V(TI)) from four anaesthesia ventilators (Aisys™, Flow-i™, Primus™, and Zeus™) on a pneumatic test lung set with three combinations of lung compliance (C, ml cm H2O(-1)) and resistance (R, cm H2O litre(-1) s(-2)): C60R5, C30R5, C60R20. For each CR, three FGF rates (0.5, 3, 10 litre min(-1)) were investigated at three set V(T)s (300, 500, 800 ml) and two values of PEEP (0 and 10 cm H2O). The volume error = [(V(TI) - V(Tset))/V(Tset)] ×100 was computed in body temperature and pressure-saturated conditions and compared using analysis of variance. For each CR and each set V(T), the absolute value of the volume error significantly declined from Aisys™ to Flow-i™, Zeus™, and Primus™. For C60R5, these values were 12.5% for Aisys™, 5% for Flow-i™ and Zeus™, and 0% for Primus™. With an increase in FGF, absolute values of the volume error increased only for Aisys™ and Zeus™. However, in C30R5, the volume error was minimal at mid-FGF for Aisys™. The results were similar at PEEP 10 cm H2O. Under experimental conditions, the volume error differed significantly between the four new anaesthesia ventilators tested and was influenced by FGF, although this effect may not be clinically relevant.

  18. Protective mechanical ventilation, why use it?

    PubMed

    Seiberlich, Emerson; Santana, Jonas Alves; Chaves, Renata de Andrade; Seiberlich, Raquel Carvalho

    2011-01-01

    Mechanical ventilation (MV) strategies have been modified over the last decades with a tendency for increasingly lower tidal volumes (VT). However, in patients without acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) the use of high VTs is still very common. Retrospective studies suggest that this practice can be related to mechanical ventilation-associated ALI. The objective of this review is to search for evidence to guide protective MV in patients with healthy lungs and to suggest strategies to properly ventilate lungs with ALI/ARDS. A review based on the main articles that focus on the use of strategies of mechanical ventilation was performed. Consistent studies to determine which would be the best way to ventilate a patient with healthy lungs are lacking. Expert recommendations and current evidence presented in this article indicate that the use of a VT lower than 10 mL.kg(-1), associated with positive end-expiratory pressure (PEEP) ≥ 5 cmH(2)O without exceeding a pressure plateau of 15 to 20 cmH(2)O could minimize alveolar stretching at the end of inspiration and avoid possible inflammation or alveolar collapse. Copyright © 2011 Elsevier Editora Ltda. All rights reserved.

  19. Adaptive support ventilation may deliver unwanted respiratory rate-tidal volume combinations in patients with acute lung injury ventilated according to an open lung concept.

    PubMed

    Dongelmans, Dave A; Paulus, Frederique; Veelo, Denise P; Binnekade, Jan M; Vroom, Margreeth B; Schultz, Marcus J

    2011-05-01

    With adaptive support ventilation, respiratory rate and tidal volume (V(T)) are a function of the Otis least work of breathing formula. We hypothesized that adaptive support ventilation in an open lung ventilator strategy would deliver higher V(T)s to patients with acute lung injury. Patients with acute lung injury were ventilated according to a local guideline advising the use of lower V(T) (6-8 ml/kg predicted body weight), high concentrations of positive end-expiratory pressure, and recruitment maneuvers. Ventilation parameters were recorded when the ventilator was switched to adaptive support ventilation, and after recruitment maneuvers. If V(T) increased more than 8 ml/kg predicted body weight, airway pressure was limited to correct for the rise of V(T). Ten patients with a mean (±SD) Pao(2)/Fio(2) of 171 ± 86 mmHg were included. After a switch from pressure-controlled ventilation to adaptive support ventilation, respiratory rate declined (from 31 ± 5 to 21 ± 6 breaths/min; difference = 10 breaths/min, 95% CI 3-17 breaths/min, P = 0.008) and V(T) increased (from 6.5 ± 0.8 to 9.0 ± 1.6 ml/kg predicted body weight; difference = 2.5 ml, 95% CI 0.4-4.6 ml/kg predicted body weight, P = 0.02). Pressure limitation corrected for the rise of V(T), but minute ventilation declined, forcing the user to switch back to pressure-controlled ventilation. Adaptive support ventilation, compared with pressure-controlled ventilation in an open lung strategy setting, delivers a lower respiratory rate-higher V(T) combination. Pressure limitation does correct for the rise of V(T), but leads to a decline in minute ventilation.

  20. Control of airborne infectious diseases in ventilated spaces

    PubMed Central

    Nielsen, Peter V.

    2009-01-01

    We protect ourselves from airborne cross-infection in the indoor environment by supplying fresh air to a room by natural or mechanical ventilation. The air is distributed in the room according to different principles: mixing ventilation, displacement ventilation, etc. A large amount of air is supplied to the room to ensure a dilution of airborne infection. Analyses of the flow in the room show that there are a number of parameters that play an important role in minimizing airborne cross-infection. The air flow rate to the room must be high, and the air distribution pattern can be designed to have high ventilation effectiveness. Furthermore, personalized ventilation may reduce the risk of cross-infection, and in some cases, it can also reduce the source of infection. Personalized ventilation can especially be used in hospital wards, aircraft cabins and, in general, where people are in fixed positions. PMID:19740921

  1. Improvements In AF Ablation Outcome Will Be Based More On Technological Advancement Versus Mechanistic Understanding.

    PubMed

    Jiang Md, Chen-Yang; Jiang Ms, Ru-Hong

    2014-01-01

    Atrial fibrillation (AF) is one of the most common cardiac arrhythmias. Catheter ablation has proven more effective than antiarrhythmic drugs in preventing clinical recurrence of AF, however long-term outcome remains unsatisfactory. Ablation strategies have evolved based on progress in mechanistic understanding, and technologies have advanced continuously. This article reviews current mechanistic concepts and technological advancements in AF treatment, and summarizes their impact on improvement of AF ablation outcome.

  2. Special Considerations in Neonatal Mechanical Ventilation.

    PubMed

    Dalgleish, Stacey; Kostecky, Linda; Charania, Irina

    2016-12-01

    Care of infants supported with mechanical ventilation is complex, time intensive, and requires constant vigilance by an expertly prepared health care team. Current evidence must guide nursing practice regarding ventilated neonates. This article highlights the importance of common language to establish a shared mental model and enhance clear communication among the interprofessional team. Knowledge regarding the underpinnings of an open lung strategy and the interplay between the pathophysiology and individual infant's response to a specific ventilator strategy is most likely to result in a positive clinical outcome. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Prevalence and test characteristics of national health safety network ventilator-associated events.

    PubMed

    Lilly, Craig M; Landry, Karen E; Sood, Rahul N; Dunnington, Cheryl H; Ellison, Richard T; Bagley, Peter H; Baker, Stephen P; Cody, Shawn; Irwin, Richard S

    2014-09-01

    The primary aim of the study was to measure the test characteristics of the National Health Safety Network ventilator-associated event/ventilator-associated condition constructs for detecting ventilator-associated pneumonia. Its secondary aims were to report the clinical features of patients with National Health Safety Network ventilator-associated event/ventilator-associated condition, measure costs of surveillance, and its susceptibility to manipulation. Prospective cohort study. Two inpatient campuses of an academic medical center. Eight thousand four hundred eight mechanically ventilated adults discharged from an ICU. None. The National Health Safety Network ventilator-associated event/ventilator-associated condition constructs detected less than a third of ventilator-associated pneumonia cases with a sensitivity of 0.325 and a positive predictive value of 0.07. Most National Health Safety Network ventilator-associated event/ventilator-associated condition cases (93%) did not have ventilator-associated pneumonia or other hospital-acquired complications; 71% met the definition for acute respiratory distress syndrome. Similarly, most patients with National Health Safety Network probable ventilator-associated pneumonia did not have ventilator-associated pneumonia because radiographic criteria were not met. National Health Safety Network ventilator-associated event/ventilator-associated condition rates were reduced 93% by an unsophisticated manipulation of ventilator management protocols. The National Health Safety Network ventilator-associated event/ventilator-associated condition constructs failed to detect many patients who had ventilator-associated pneumonia, detected many cases that did not have a hospital complication, and were susceptible to manipulation. National Health Safety Network ventilator-associated event/ventilator-associated condition surveillance did not perform as well as ventilator-associated pneumonia surveillance and had several undesirable

  4. Variation in Definition of Prolonged Mechanical Ventilation.

    PubMed

    Rose, Louise; McGinlay, Michael; Amin, Reshma; Burns, Karen Ea; Connolly, Bronwen; Hart, Nicholas; Jouvet, Philippe; Katz, Sherri; Leasa, David; Mawdsley, Cathy; McAuley, Danny F; Schultz, Marcus J; Blackwood, Bronagh

    2017-10-01

    Consistency of definitional criteria for terminology applied to describe subject cohorts receiving mechanical ventilation within ICU and post-acute care settings is important for understanding prevalence, risk stratification, effectiveness of interventions, and projections for resource allocation. Our objective was to quantify the application and definition of terms for prolonged mechanical ventilation. We conducted a scoping review of studies (all designs except single-case study) reporting a study population (adult and pediatric) using the term prolonged mechanical ventilation or a synonym. We screened 5,331 references, reviewed 539 full-text references, and excluded 120. Of the 419 studies (representing 38 countries) meeting inclusion criteria, 297 (71%) reported data on a heterogeneous subject cohort, and 66 (16%) included surgical subjects only (46 of those 66, 70% cardiac surgery). Other studies described COPD (16, 4%), trauma (22, 5%), neuromuscular (17, 4%), and sepsis (1, 0.2%) cohorts. A total of 741 terms were used to refer to the 419 study cohorts. The most common terms were: prolonged mechanical ventilation (253, 60%), admission to specialized unit (107, 26%), and long-term mechanical ventilation (79, 19%). Some authors (282, 67%) defined their cohorts based on duration of mechanical ventilation, with 154 studies (55%) using this as the sole criterion. We identified 37 different durations of ventilation ranging from 5 h to 1 y, with > 21 d being the most common (28 of 282, 7%). For studies describing a surgical cohort, minimum ventilation duration required for inclusion was ≥ 24 h for 20 of 66 studies (30%). More than half of all studies (237, 57%) did not provide a reason/rationale for definitional criteria used, with only 28 studies (7%) referring to a consensus definition. We conclude that substantial variation exists in the terminology and definitional criteria for cohorts of subjects receiving prolonged mechanical ventilation. Standardization of

  5. 46 CFR 72.15-15 - Ventilation for closed spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 3 2011-10-01 2011-10-01 false Ventilation for closed spaces. 72.15-15 Section 72.15-15... ARRANGEMENT Ventilation § 72.15-15 Ventilation for closed spaces. (a) All enclosed spaces within the vessel... spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings to...

  6. 46 CFR 92.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Ventilation for closed spaces. 92.15-10 Section 92.15-10... CONSTRUCTION AND ARRANGEMENT Ventilation § 92.15-10 Ventilation for closed spaces. (a) Except as noted in paragraph (c) of this section, all enclosed spaces within the vessel shall be properly vented or ventilated...

  7. 46 CFR 72.15-15 - Ventilation for closed spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 3 2013-10-01 2013-10-01 false Ventilation for closed spaces. 72.15-15 Section 72.15-15... ARRANGEMENT Ventilation § 72.15-15 Ventilation for closed spaces. (a) All enclosed spaces within the vessel... spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings to...

  8. 46 CFR 92.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Ventilation for closed spaces. 92.15-10 Section 92.15-10... CONSTRUCTION AND ARRANGEMENT Ventilation § 92.15-10 Ventilation for closed spaces. (a) Except as noted in paragraph (c) of this section, all enclosed spaces within the vessel shall be properly vented or ventilated...

  9. 46 CFR 92.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Ventilation for closed spaces. 92.15-10 Section 92.15-10... CONSTRUCTION AND ARRANGEMENT Ventilation § 92.15-10 Ventilation for closed spaces. (a) Except as noted in paragraph (c) of this section, all enclosed spaces within the vessel shall be properly vented or ventilated...

  10. 46 CFR 72.15-15 - Ventilation for closed spaces.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Ventilation for closed spaces. 72.15-15 Section 72.15-15... ARRANGEMENT Ventilation § 72.15-15 Ventilation for closed spaces. (a) All enclosed spaces within the vessel... spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings to...

  11. 46 CFR 92.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Ventilation for closed spaces. 92.15-10 Section 92.15-10... CONSTRUCTION AND ARRANGEMENT Ventilation § 92.15-10 Ventilation for closed spaces. (a) Except as noted in paragraph (c) of this section, all enclosed spaces within the vessel shall be properly vented or ventilated...

  12. 46 CFR 72.15-15 - Ventilation for closed spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 3 2014-10-01 2014-10-01 false Ventilation for closed spaces. 72.15-15 Section 72.15-15... ARRANGEMENT Ventilation § 72.15-15 Ventilation for closed spaces. (a) All enclosed spaces within the vessel... spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings to...

  13. 46 CFR 92.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Ventilation for closed spaces. 92.15-10 Section 92.15-10... CONSTRUCTION AND ARRANGEMENT Ventilation § 92.15-10 Ventilation for closed spaces. (a) Except as noted in paragraph (c) of this section, all enclosed spaces within the vessel shall be properly vented or ventilated...

  14. 46 CFR 72.15-15 - Ventilation for closed spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 3 2012-10-01 2012-10-01 false Ventilation for closed spaces. 72.15-15 Section 72.15-15... ARRANGEMENT Ventilation § 72.15-15 Ventilation for closed spaces. (a) All enclosed spaces within the vessel... spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings to...

  15. Ultra-Short-Course Antibiotics for Patients With Suspected Ventilator-Associated Pneumonia but Minimal and Stable Ventilator Settings.

    PubMed

    Klompas, Michael; Li, Lingling; Menchaca, John T; Gruber, Susan

    2017-04-01

    Many patients started on antibiotics for possible ventilator-associated pneumonia (VAP) do not have pneumonia. Patients with minimal and stable ventilator settings may be suitable candidates for early antibiotic discontinuation. We compared outcomes among patients with suspected VAP but minimal and stable ventilator settings treated with 1-3 days vs >3 days of antibiotics. We identified consecutive adult patients started on antibiotics for possible VAP with daily minimum positive end-expiratory pressure of ≤5 cm H2O and fraction of inspired oxygen ≤40% for at least 3 days within a large tertiary care hospital between 2006 and 2014. We compared time to extubation alive vs ventilator death and time to hospital discharge alive vs hospital death using competing risks models among patients prescribed 1-3 days vs >3 days of antibiotics. All models were adjusted for patient demographics, comorbidities, severity of illness, clinical signs of infection, and pathogens. There were 1290 eligible patients, 259 treated for 1-3 days and 1031 treated for >3 days. The 2 groups had similar demographics, comorbidities, and clinical signs. There were no significant differences between groups in time to extubation alive (hazard ratio [HR], 1.16 for short- vs long-course treatment; 95% confidence interval [CI], .98-1.36), ventilator death (HR, 0.82 [95% CI, .55-1.22]), time to hospital discharge alive (HR, 1.07 [95% CI, .91-1.26]), or hospital death (HR, 0.99 [95% CI, .75-1.31]). Very short antibiotic courses (1-3 days) were associated with outcomes similar to longer courses (>3 days) in patients with suspected VAP but minimal and stable ventilator settings. Assessing serial ventilator settings may help clinicians identify candidates for early antibiotic discontinuation. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  16. Exchange bias mechanism in FM/FM/AF spin valve systems in the presence of random unidirectional anisotropy field at the AF interface: The role played by the interface roughness due to randomness

    NASA Astrophysics Data System (ADS)

    Yüksel, Yusuf

    2018-05-01

    We propose an atomistic model and present Monte Carlo simulation results regarding the influence of FM/AF interface structure on the hysteresis mechanism and exchange bias behavior for a spin valve type FM/FM/AF magnetic junction. We simulate perfectly flat and roughened interface structures both with uncompensated interfacial AF moments. In order to simulate rough interface effect, we introduce the concept of random exchange anisotropy field induced at the interface, and acting on the interface AF spins. Our results yield that different types of the random field distributions of anisotropy field may lead to different behavior of exchange bias.

  17. Evaluation of Fractional Regional Ventilation Using 4D-CT and Effects of Breathing Maneuvers on Ventilation

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

    Mistry, Nilesh N., E-mail: nmistry@som.umaryland.edu; Diwanji, Tejan; Shi, Xiutao

    2013-11-15

    Purpose: Current implementations of methods based on Hounsfield units to evaluate regional lung ventilation do not directly incorporate tissue-based mass changes that occur over the respiratory cycle. To overcome this, we developed a 4-dimensional computed tomography (4D-CT)-based technique to evaluate fractional regional ventilation (FRV) that uses an individualized ratio of tidal volume to end-expiratory lung volume for each voxel. We further evaluated the effect of different breathing maneuvers on regional ventilation. The results from this work will help elucidate the relationship between global and regional lung function. Methods and Materials: Eight patients underwent 3 sets of 4D-CT scans during 1more » session using free-breathing, audiovisual guidance, and active breathing control. FRV was estimated using a density-based algorithm with mass correction. Internal validation between global and regional ventilation was performed by use of the imaging data collected during the use of active breathing control. The impact of breathing maneuvers on FRV was evaluated comparing the tidal volume from 3 breathing methods. Results: Internal validation through comparison between the global and regional changes in ventilation revealed a strong linear correlation (slope of 1.01, R{sup 2} of 0.97) between the measured global lung volume and the regional lung volume calculated by use of the “mass corrected” FRV. A linear relationship was established between the tidal volume measured with the automated breathing control system and FRV based on 4D-CT imaging. Consistently larger breathing volumes were observed when coached breathing techniques were used. Conclusions: The technique presented improves density-based evaluation of lung ventilation and establishes a link between global and regional lung ventilation volumes. Furthermore, the results obtained are comparable with those of other techniques of functional evaluation such as spirometry and hyperpolarized

  18. 30 CFR 75.350 - Belt air course ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.350 Belt air course ventilation... manager may approve lower velocities in the ventilation plan based on specific mine conditions. Air... or alarm signal. This training must be conducted prior to working underground in a mine that uses...

  19. 30 CFR 77.1106 - Battery-charging stations; ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Battery-charging stations; ventilation. 77.1106... COAL MINES Fire Protection § 77.1106 Battery-charging stations; ventilation. Battery-charging stations shall be located in well-ventilated areas. Battery-charging stations shall be equipped with reverse...

  20. 30 CFR 77.1106 - Battery-charging stations; ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Battery-charging stations; ventilation. 77.1106... COAL MINES Fire Protection § 77.1106 Battery-charging stations; ventilation. Battery-charging stations shall be located in well-ventilated areas. Battery-charging stations shall be equipped with reverse...

  1. 30 CFR 77.1106 - Battery-charging stations; ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Battery-charging stations; ventilation. 77.1106... COAL MINES Fire Protection § 77.1106 Battery-charging stations; ventilation. Battery-charging stations shall be located in well-ventilated areas. Battery-charging stations shall be equipped with reverse...

  2. 30 CFR 77.1106 - Battery-charging stations; ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Battery-charging stations; ventilation. 77.1106... COAL MINES Fire Protection § 77.1106 Battery-charging stations; ventilation. Battery-charging stations shall be located in well-ventilated areas. Battery-charging stations shall be equipped with reverse...

  3. 30 CFR 77.1106 - Battery-charging stations; ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Battery-charging stations; ventilation. 77.1106... COAL MINES Fire Protection § 77.1106 Battery-charging stations; ventilation. Battery-charging stations shall be located in well-ventilated areas. Battery-charging stations shall be equipped with reverse...

  4. 21 CFR 868.5935 - External negative pressure ventilator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... ventilator. (a) Identification. An external negative pressure ventilator (e.g., iron lung, cuirass) is a device chamber that is intended to support a patient's ventilation by alternately applying and releasing external negative pressure over the diaphragm and upper trunk of the patient. (b) Classification. Class II...

  5. A Critical Role for CRM1 in Regulating HOXA Gene Transcription in CALM-AF10 Leukemias

    PubMed Central

    Conway, Amanda E.; Haldeman, Jonathan M.; Wechsler, Daniel S.; Lavau, Catherine P.

    2014-01-01

    The leukemogenic CALM-AF10 fusion protein is found in patients with immature acute myeloid and T-lymphoid malignancies. CALM-AF10 leukemias display abnormal H3K79 methylation and increased HOXA cluster gene transcription. Elevated expression of HOXA genes is critical for leukemia maintenance and progression; however, the precise mechanism by which CALM-AF10 alters HOXA gene expression is unclear. We previously determined that CALM contains a CRM1-dependent nuclear export signal (NES), which is both necessary and sufficient for CALM-AF10-mediated leukemogenesis. Here, we find that interaction of CALM-AF10 with the nuclear export receptor CRM1 is necessary for activating HOXA gene expression. We show that CRM1 localizes to HOXA loci where it recruits CALM-AF10, leading to transcriptional and epigenetic activation of HOXA genes. Genetic and pharmacological inhibition of the CALM-CRM1 interaction prevents CALM-AF10 enrichment at HOXA chromatin, resulting in immediate loss of transcription. These results provide a comprehensive mechanism by which the CALM-AF10 translocation activates the critical HOXA cluster genes. Furthermore, this report identifies a novel function of CRM1: the ability to bind chromatin and recruit the NES-containing CALM-AF10 transcription factor. PMID:25027513

  6. A miniature mechanical ventilator for newborn mice.

    PubMed

    Kolandaivelu, K; Poon, C S

    1998-02-01

    Transgenic/knockout mice with pre-defined mutations have become increasingly popular in biomedical research as models of human diseases. In some instances, the resulting mutation may cause cardiorespiratory distress in the neonatal or adult animals and may necessitate resuscitation. Here we describe the design and testing of a miniature and versatile ventilator that can deliver varying ventilatory support modes, including conventional mechanical ventilation and high-frequency ventilation, to animals as small as the newborn mouse. With a double-piston body chamber design, the device circumvents the problem of air leakage and obviates the need for invasive procedures such as endotracheal intubation, which are particularly important in ventilating small animals. Preliminary tests on newborn mice as early as postnatal day O demonstrated satisfactory restoration of pulmonary ventilation and the prevention of respiratory failure in mutant mice that are prone to respiratory depression. This device may prove useful in the postnatal management of transgenic/knockout mice with genetically inflicted respiratory disorders.

  7. Characterizing the chaotic nature of ocean ventilation

    NASA Astrophysics Data System (ADS)

    MacGilchrist, Graeme A.; Marshall, David P.; Johnson, Helen L.; Lique, Camille; Thomas, Matthew

    2017-09-01

    Ventilation of the upper ocean plays an important role in climate variability on interannual to decadal timescales by influencing the exchange of heat and carbon dioxide between the atmosphere and ocean. The turbulent nature of ocean circulation, manifest in a vigorous mesoscale eddy field, means that pathways of ventilation, once thought to be quasi-laminar, are in fact highly chaotic. We characterize the chaotic nature of ventilation pathways according to a nondimensional "filamentation number," which estimates the reduction in filament width of a ventilated fluid parcel due to mesoscale strain. In the subtropical North Atlantic of an eddy-permitting ocean model, the filamentation number is large everywhere across three upper ocean density surfaces—implying highly chaotic ventilation pathways—and increases with depth. By mapping surface ocean properties onto these density surfaces, we directly resolve the highly filamented structure and confirm that the filamentation number captures its spatial variability. These results have implications for the spreading of atmospherically-derived tracers into the ocean interior.

  8. Comparison of exogenous surfactant therapy, mechanical ventilation with high end-expiratory pressure and partial liquid ventilation in a model of acute lung injury.

    PubMed

    Hartog, A; Vazquez de Anda, G F; Gommers, D; Kaisers, U; Verbrugge, S J; Schnabel, R; Lachmann, B

    1999-01-01

    We have compared three treatment strategies, that aim to prevent repetitive alveolar collapse, for their effect on gas exchange, lung mechanics, lung injury, protein transfer into the alveoli and surfactant system, in a model of acute lung injury. In adult rats, the lungs were ventilated mechanically with 100% oxygen and a PEEP of 6 cm H2O, and acute lung injury was induced by repeated lung lavage to obtain a PaO2 value < 13 kPa. Animals were then allocated randomly (n = 12 in each group) to receive exogenous surfactant therapy, ventilation with high PEEP (18 cm H2O), partial liquid ventilation or ventilation with low PEEP (8 cm H2O) (ventilated controls). Blood-gas values were measured hourly. At the end of the 4-h study, in six animals per group, pressure-volume curves were constructed and bronchoalveolar lavage (BAL) was performed, whereas in the remaining animals lung injury was assessed. In the ventilated control group, arterial oxygenation did not improve and protein concentration of BAL and conversion of active to non-active surfactant components increased significantly. In the three treatment groups, PaO2 increased rapidly to > 50 kPa and remained stable over the next 4 h. The protein concentration of BAL fluid increased significantly only in the partial liquid ventilation group. Conversion of active to non-active surfactant components increased significantly in the partial liquid ventilation group and in the group ventilated with high PEEP. In the surfactant group and partial liquid ventilation groups, less lung injury was found compared with the ventilated control group and the group ventilated with high PEEP. We conclude that although all three strategies improved PaO2 to > 50 kPa, the impact on protein transfer into the alveoli, surfactant system and lung injury differed markedly.

  9. Mechanical Ventilation and ARDS in the ED

    PubMed Central

    Mohr, Nicholas M.; Miller, Christopher N.; Deitchman, Andrew R.; Castagno, Nicole; Hassebroek, Elizabeth C.; Dhedhi, Adam; Scott-Wittenborn, Nicholas; Grace, Edward; Lehew, Courtney; Kollef, Marin H.

    2015-01-01

    BACKGROUND: There are few data regarding mechanical ventilation and ARDS in the ED. This could be a vital arena for prevention and treatment. METHODS: This study was a multicenter, observational, prospective, cohort study aimed at analyzing ventilation practices in the ED. The primary outcome was the incidence of ARDS after admission. Multivariable logistic regression was used to determine the predictors of ARDS. RESULTS: We analyzed 219 patients receiving mechanical ventilation to assess ED ventilation practices. Median tidal volume was 7.6 mL/kg predicted body weight (PBW) (interquartile range, 6.9-8.9), with a range of 4.3 to 12.2 mL/kg PBW. Lung-protective ventilation was used in 122 patients (55.7%). The incidence of ARDS after admission from the ED was 14.7%, with a mean onset of 2.3 days. Progression to ARDS was associated with higher illness severity and intubation in the prehospital environment or transferring facility. Of the 15 patients with ARDS in the ED (6.8%), lung-protective ventilation was used in seven (46.7%). Patients who progressed to ARDS experienced greater duration in organ failure and ICU length of stay and higher mortality. CONCLUSIONS: Lung-protective ventilation is infrequent in patients receiving mechanical ventilation in the ED, regardless of ARDS status. Progression to ARDS is common after admission, occurs early, and worsens outcome. Patient- and treatment-related factors present in the ED are associated with ARDS. Given the limited treatment options for ARDS, and the early onset after admission from the ED, measures to prevent onset and to mitigate severity should be instituted in the ED. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT01628523; URL: www.clinicaltrials.gov PMID:25742126

  10. Validating and improving CT ventilation imaging by correlating with ventilation 4D-PET/CT using {sup 68}Ga-labeled nanoparticles

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

    Kipritidis, John, E-mail: john.kipritidis@sydney.edu.au; Keall, Paul J.; Siva, Shankar

    Purpose: CT ventilation imaging is a novel functional lung imaging modality based on deformable image registration. The authors present the first validation study of CT ventilation using positron emission tomography with{sup 68}Ga-labeled nanoparticles (PET-Galligas). The authors quantify this agreement for different CT ventilation metrics and PET reconstruction parameters. Methods: PET-Galligas ventilation scans were acquired for 12 lung cancer patients using a four-dimensional (4D) PET/CT scanner. CT ventilation images were then produced by applying B-spline deformable image registration between the respiratory correlated phases of the 4D-CT. The authors test four ventilation metrics, two existing and two modified. The two existing metricsmore » model mechanical ventilation (alveolar air-flow) based on Hounsfield unit (HU) change (V{sub HU}) or Jacobian determinant of deformation (V{sub Jac}). The two modified metrics incorporate a voxel-wise tissue-density scaling (ρV{sub HU} and ρV{sub Jac}) and were hypothesized to better model the physiological ventilation. In order to assess the impact of PET image quality, comparisons were performed using both standard and respiratory-gated PET images with the former exhibiting better signal. Different median filtering kernels (σ{sub m} = 0 or 3 mm) were also applied to all images. As in previous studies, similarity metrics included the Spearman correlation coefficient r within the segmented lung volumes, and Dice coefficient d{sub 20} for the (0 − 20)th functional percentile volumes. Results: The best agreement between CT and PET ventilation was obtained comparing standard PET images to the density-scaled HU metric (ρV{sub HU}) with σ{sub m} = 3 mm. This leads to correlation values in the ranges 0.22 ⩽ r ⩽ 0.76 and 0.38 ⩽ d{sub 20} ⩽ 0.68, with r{sup ¯}=0.42±0.16 and d{sup ¯}{sub 20}=0.52±0.09 averaged over the 12 patients. Compared to Jacobian-based metrics, HU-based metrics lead to statistically

  11. Pre-clinical laboratory evaluation of the new 'AF' arterial line filter range.

    PubMed

    Yarham, Gemma; Mulholland, John

    2010-07-01

    The presence of emboli was recognised relatively early in the history of open heart surgery. The emboli produced during cardiopulmonary bypass have the predisposition to distribute into, and ultimately obstruct, microvessels of all tissues. The Sorin Group has recently developed a new range of arterial line filters. Before the Sorin AF range of filters was released for pre-launch clinical trials, our group performed in vitro laboratory testing of the AF range against a selection of commercially available filters on the global market. The Sorin AF620 and AF640 demonstrate both the smallest prime volume and smallest surface contact area (92ml and 290 cm(2), respectively).The results of the GME Handling Efficiency experiments ranged by 39.6%, from 95.9% to 56.3%. In terms of an air bolus handling, the results of the Limit Bolus experiment ranged by 97 ml, from 147.5 ml down to 50 ml. The pressure drop across all the filters was measured under steady state experimental conditions. All of the above investigations were considered against surface area and prime volume. It is clear from the results that some commercially available arterial line filters perform better than others, not only in overall performance, but also with regard to individual characteristics. Evaluating arterial line filters for hospital-specific use has to balance pressure drop, surface area, micro air handling, prime volume and gross air handling; all points need to be considered. In the AF620 and AF640, Sorin boast that they are the two smallest prime and smallest surface area filters commercially available on the global market. The Sorin AF filter range performs well in all of the areas we investigated and will be a competitive option for centres, irrespective of which characteristics they use to evaluate and select their arterial line filter.

  12. Detection of atrial fibrillation and flutter by a dual-chamber implantable cardioverter-defibrillator. For the Worldwide Jewel AF Investigators.

    PubMed

    Swerdlow, C D; Schsls, W; Dijkman, B; Jung, W; Sheth, N V; Olson, W H; Gunderson, B D

    2000-02-29

    To distinguish prolonged episodes of atrial fibrillation (AF) that require cardioversion from self-terminating episodes that do not, an atrial implantable cardioverter-defibrillator (ICD) must be able to detect AF continuously for extended periods. The ICD should discriminate between atrial tachycardia/flutter (AT), which may be terminated by antitachycardia pacing, and AF, which requires cardioversion. We studied 80 patients with AT/AF and ventricular arrhythmias who were treated with a new atrial/dual-chamber ICD. During a follow-up period lasting 6+/-2 months, we validated spontaneous, device-defined AT/AF episodes by stored electrograms in all patients. In 58 patients, we performed 80 Holter recordings with telemetered atrial electrograms, both to validate the continuous detection of AT/AF and to determine the sensitivity of the detection of AT/AF. Detection was appropriate in 98% of 132 AF episodes and 88% of 190 AT episodes (98% of 128 AT episodes with an atrial cycle length <300 ms). Intermittent sensing of far-field R waves during sinus tachycardia caused 27 inappropriate AT/AF detections; these detections lasted 2.6+/-2.0 minutes. AT/AF was detected continuously in 27 of 28 patients who had spontaneous episodes of AT/AF (96%). The device memory recorded 90 appropriate AT/AF episodes lasting >1 hour, for a total of 2697 hours of continuous detection of AT/AF. During Holter monitoring, the sensitivity of the detection of AT/AF (116 hours) was 100%; the specificity of the detection of non-AT/AF rhythms (1290 hours) was 99.99%. Of 166 appropriate episodes detected as AT, 45% were terminated by antitachycardia pacing. A new ICD detects AT/AF accurately and continuously. Therapy may be programmed for long-duration AT/AF, with a low risk of underdetection. Discrimination of AT from AF permits successful pacing therapy for a significant fraction of AT.

  13. The use of mechanical ventilation in the ED.

    PubMed

    Easter, Benjamin D; Fischer, Christopher; Fisher, Jonathan

    2012-09-01

    Although EDs are responsible for the initial care of critically ill patients and the amount of critical care provided in the ED is increasing, there are few data examining mechanical ventilation (MV) in the ED. In addition, characteristics of ED-based ventilation may affect planning for ventilator shortages during pandemic influenza or bioterrorist events. The study examined the epidemiology of MV in US EDs, including demographic, clinical, and hospital characteristics; indications for MV; ED length of stay (LOS); and in-hospital mortality. This study was a retrospective review of the 1993 to 2007 National Hospital Ambulatory Medical Care Survey ED data sets. Ventilated patients were compared with ED patients admitted to the intensive care unit (ICU) and to all other ED visits. There were 3.6 million ED MV visits (95% confidence interval [CI], 3.2-4.0 million) over the study period. Sex, age, race, and payment source were similar for mechanically ventilated and ICU patients (P > .05 for all). Approximately 12.5% of ventilated patients underwent cardiopulmonary resuscitation compared with 1.7% of ICU admissions and 0.2% of all other ED visits (P < .0001). Accordingly, in-hospital mortality was significantly higher for ventilated patients (24%; 95% CI, 13.1%-34.9%) than both comparison groups (9.3% and 2.5%, respectively). Median LOS for ventilated patients was 197 minutes (interquartile range, 112-313 minutes) compared with 224 minutes for ICU admissions and 140 minutes for all other ED visits. Patients undergoing ED MV have particularly high in-hospital mortality rates, but their ED LOS is sufficient for implementation of evidence-based ventilator interventions. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. AFS Estuaries Section - A Successful Partnership

    EPA Science Inventory

    The Estuaries Section of the American Fisheries Society offers travel awards to students in support of their attendance and presentations at the AFS meeting. Since 2007, the Southern Association of Marine Laboratories has partnered with the Estuaries Section to sponsor two stude...

  15. Histochemical alterations in one lung ventilation.

    PubMed

    Yin, Kingsley; Gribbin, Elizabeth; Emanuel, Steven; Orndorff, Rebecca; Walker, Jean; Weese, James; Fallahnejad, Manucher

    2007-01-01

    One lung ventilation is a commonly performed surgical procedure. Although there have been several reports showing that one-lung ventilation can cause pathophysiological alterations such as pulmonary hypoxic vasoconstriction and intrapulmonary shunting, there have been virtually no reports on the effects of one-lung ventilation on lung histology. Yorkshire pigs (11-17 kg) were anesthetized, a tracheotomy performed and a tracheal tube inserted. The chest was opened and one lung ventilation (OLV), was induced by clamping of the right main bronchus. OLV was continued for 60 min before the clamp was removed and two lung ventilation (TLV) started. TLV was continued for 30 to 60 min. Blood and lung biopsies were taken immediately before OLV, 30 min and 60 min of OLV and after restoration of TLV. Histological analyses revealed that the non-ventilated lung was totally collapsed during OLV. On reventilation, there was clear evidence of vascular congestion and alveolar wall thickening at 30 min after TLV. At 60 min of TLV, there was still vascular congestion. Serum nitrite levels (as an index of nitric oxide production) showed steady decline over the course of the experimental period, reaching a significantly low level on reventilation (compared with baseline levels before OLV). Lung MPO activity (marker of neutrophil sequestration) and serum TNFalpha levels were not raised during the entire experimental period. These results suggest that there was lung vascular injury after OLV, which was associated with reduced levels of nitric oxide production and not associated with an inflammatory response.

  16. Thermoregulation and ventilation of termite mounds.

    PubMed

    Korb, Judith

    2003-05-01

    Some of the most sophisticated of all animal-built structures are the mounds of African termites of the subfamily Macrotermitinae, the fungus-growing termites. They have long been studied as fascinating textbook examples of thermoregulation or ventilation of animal buildings. However, little research has been designed to provide critical tests of these paradigms, derived from a very small number of original papers. Here I review results from recent studies on Macrotermes bellicosus that considered the interdependence of ambient temperature, thermoregulation, ventilation and mound architecture, and that question some of the fundamental paradigms of termite mounds. M. bellicosus achieves thermal homeostasis within the mound, but ambient temperature has an influence too. In colonies in comparably cool habitats, mound architecture is adapted to reduce the loss of metabolically produced heat to the environment. While this has no negative consequences in small colonies, it produces a trade-off with gas exchange in large colonies, resulting in suboptimally low nest temperatures and increased CO(2) concentrations. Along with the alteration in mound architecture, the gas exchange/ventilation mechanism also changes. While mounds in the thermally appropriate savannah have a very efficient circular ventilation during the day, the ventilation in the cooler forest is a less efficient upward movement of air, with gas exchange restricted by reduced surface exchange area. These results, together with other recent findings, question entrenched ideas such as the thermosiphon-ventilation mechanism or the assumption that mounds function to dissipate internally produced heat. Models trying to explain the proximate mechanisms of mound building, or building elements, are discussed.

  17. Thermoregulation and ventilation of termite mounds

    NASA Astrophysics Data System (ADS)

    Korb, Judith

    2003-05-01

    Some of the most sophisticated of all animal-built structures are the mounds of African termites of the subfamily Macrotermitinae, the fungus-growing termites. They have long been studied as fascinating textbook examples of thermoregulation or ventilation of animal buildings. However, little research has been designed to provide critical tests of these paradigms, derived from a very small number of original papers. Here I review results from recent studies on Macrotermes bellicosus that considered the interdependence of ambient temperature, thermoregulation, ventilation and mound architecture, and that question some of the fundamental paradigms of termite mounds. M. bellicosus achieves thermal homeostasis within the mound, but ambient temperature has an influence too. In colonies in comparably cool habitats, mound architecture is adapted to reduce the loss of metabolically produced heat to the environment. While this has no negative consequences in small colonies, it produces a trade-off with gas exchange in large colonies, resulting in suboptimally low nest temperatures and increased CO2 concentrations. Along with the alteration in mound architecture, the gas exchange/ventilation mechanism also changes. While mounds in the thermally appropriate savannah have a very efficient circular ventilation during the day, the ventilation in the cooler forest is a less efficient upward movement of air, with gas exchange restricted by reduced surface exchange area. These results, together with other recent findings, question entrenched ideas such as the thermosiphon-ventilation mechanism or the assumption that mounds function to dissipate internally produced heat. Models trying to explain the proximate mechanisms of mound building, or building elements, are discussed.

  18. [Oxidative stress in patients on mechanical ventilation].

    PubMed

    Marjanović, Vesna; Dordević, Vidosava; Marjanović, Goran

    2009-01-01

    The appearance and intensity of oxidative stress were analyzed in the course of mechanical ventilation and parameters that could point toward potential lung damage. In three time intervals on day 1, 3 and 7 of mechanical ventilation, parameters such as: triglycerides, cholesterol, lactate, serum lactic dehydrogenase, acid-base balance and lipid peroxidation products--thiobarbituric acid reactive substances, were followed in 30 patients with head injuries. A decrease in the level of partial oxygen pressure (PaO2) (p < 0.01) and PaO2/FiO2 index (p < 0.05) in arterial blood was recorded on day 3 of mechanical ventilation. This was accompanied with an increase in alveolar-arterial difference (AaDO2) (p < 0.05), thiobarbituric acid reactive substances (p < 0.001) and lactic dehydrogenase (p < 0.001) comparing to day 1 of mechanical ventilation. The patients with initial PaO2 > 120 mmHg, had significant increase of thiobarbituric acid reactive substances and AaDO2 (p < 0.05) and fall of PaO2 (p < 0.001) on day 3 of mechanical ventilation. Oxidative stress and lipid peroxide production are increased during third day of mechanical ventilation leading to disruption of oxygen diffusion through alveolar-capillary membrane and reduction of parameters of oxygenation.

  19. Characteristics and outcomes of ventilated patients according to time to liberation from mechanical ventilation.

    PubMed

    Peñuelas, Oscar; Frutos-Vivar, Fernando; Fernández, Cristina; Anzueto, Antonio; Epstein, Scott K; Apezteguía, Carlos; González, Marco; Nin, Nicholas; Raymondos, Konstantinos; Tomicic, Vinko; Desmery, Pablo; Arabi, Yaseen; Pelosi, Paolo; Kuiper, Michael; Jibaja, Manuel; Matamis, Dimitros; Ferguson, Niall D; Esteban, Andrés

    2011-08-15

    A new classification of patients based on the duration of liberation of mechanical ventilation has been proposed. To analyze outcomes based on the new weaning classification in a cohort of mechanically ventilated patients. Secondary analysis included 2,714 patients who were weaned and underwent scheduled extubation from a cohort of 4,968 adult patients mechanically ventilated for more than 12 hours. Patients were classified according to a new weaning classification: 1,502 patients (55%) as simple weaning,1,058 patients (39%) as difficult weaning, and 154 (6%) as prolonged weaning.Variables associated with prolonged weaning(.7d)were: severity at admission (odds ratio [OR] per unit of Simplified Acute Physiology Score II, 1.01; 95% confidence interval [CI], 1.001–1.02), duration of mechanical ventilation before first attempt of weaning (OR per day, 1.10; 95% CI, 1.06–1.13), chronic pulmonary disease other than chronic obstructive pulmonary disease (OR,13.23; 95% CI, 3.44–51.05), pneumonia as the reason to start mechanical ventilation (OR, 1.82; 95% CI, 1.07–3.08), and level of positive end-expiratory pressure applied before weaning (OR per unit,1.09; 95% CI, 1.04–1.14). The prolonged weaning group had a nonsignificant trend toward a higher rate of reintubation (P ¼ 0.08),tracheostomy (P ¼ 0.15), and significantly longer length of stay and higher mortality in the intensive care unit (OR for death, 1.97;95%CI, 1.17–3.31). The adjusted probability of death remained constant until Day 7, at which point it increased to 12.1%.

  20. 46 CFR 127.250 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Ventilation for enclosed spaces. 127.250 Section 127.250... ARRANGEMENTS Particular Construction and Arrangements § 127.250 Ventilation for enclosed spaces. (a) Each enclosed space within the vessel must be properly vented or ventilated. Means must be provided for closing...

  1. 46 CFR 127.250 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Ventilation for enclosed spaces. 127.250 Section 127.250... ARRANGEMENTS Particular Construction and Arrangements § 127.250 Ventilation for enclosed spaces. (a) Each enclosed space within the vessel must be properly vented or ventilated. Means must be provided for closing...

  2. 46 CFR 127.250 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Ventilation for enclosed spaces. 127.250 Section 127.250... ARRANGEMENTS Particular Construction and Arrangements § 127.250 Ventilation for enclosed spaces. (a) Each enclosed space within the vessel must be properly vented or ventilated. Means must be provided for closing...

  3. 46 CFR 127.250 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Ventilation for enclosed spaces. 127.250 Section 127.250... ARRANGEMENTS Particular Construction and Arrangements § 127.250 Ventilation for enclosed spaces. (a) Each enclosed space within the vessel must be properly vented or ventilated. Means must be provided for closing...

  4. 46 CFR 127.250 - Ventilation for enclosed spaces.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Ventilation for enclosed spaces. 127.250 Section 127.250... ARRANGEMENTS Particular Construction and Arrangements § 127.250 Ventilation for enclosed spaces. (a) Each enclosed space within the vessel must be properly vented or ventilated. Means must be provided for closing...

  5. 33 CFR 183.630 - Standards for natural ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Standards for natural ventilation... (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Ventilation § 183.630 Standards for natural ventilation. (a) For the purpose of § 183.620, “natural ventilation” means an airflow in a compartment in a...

  6. 33 CFR 183.630 - Standards for natural ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Standards for natural ventilation... (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Ventilation § 183.630 Standards for natural ventilation. (a) For the purpose of § 183.620, “natural ventilation” means an airflow in a compartment in a...

  7. Mask leak increases and minute ventilation decreases when chest compressions are added to bag ventilation in a neonatal manikin model.

    PubMed

    Tracy, Mark B; Shah, Dharmesh; Hinder, Murray; Klimek, Jan; Marceau, James; Wright, Audrey

    2014-05-01

    To determine changes in respiratory mechanics when chest compressions are added to mask ventilation, as recommended by the International Liaison Committee on Resuscitation (ILCOR) guidelines for newborn infants. Using a Laerdal Advanced Life Support leak-free baby manikin and a 240-mL self-inflating bag, 58 neonatal staff members were randomly paired to provide mask ventilation, followed by mask ventilation with chest compressions with a 1:3 ratio, for two minutes each. A Florian respiratory function monitor was used to measure respiratory mechanics, including mask leak. The addition of chest compressions to mask ventilation led to a significant reduction in inflation rate, from 63.9 to 32.9 breaths per minute (p < 0.0001), mean airway pressure reduced from 7.6 to 4.9 cm H2 O (p < 0.001), minute ventilation reduced from 770 to 451 mL/kg/min (p < 0.0001), and there was a significant increase in paired mask leak of 6.8% (p < 0.0001). Adding chest compressions to mask ventilation, in accordance with the ILCOR guidelines, in a manikin model is associated with a significant reduction in delivered ventilation and increase in mask leak. If similar findings occur in human infants needing an escalation in resuscitation, there is a potential risk of either delay in recovery or inadequate response to resuscitation. ©2014 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  8. 49 CFR 192.173 - Compressor stations: Ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Design of Pipeline Components § 192.173 Compressor stations: Ventilation. Each compressor station building must be ventilated to ensure...

  9. Ventilation System Effectiveness and Tested Indoor Air Quality Impacts

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

    Rudd, Armin; Bergey, Daniel

    Ventilation system effectiveness testing was conducted at two unoccupied, single-family, detached lab homes at the University of Texas - Tyler. Five ventilation system tests were conducted with various whole-building ventilation systems. Multizone fan pressurization testing characterized building and zone enclosure leakage. PFT testing showed multizone air change rates and interzonal airflow. Cumulative particle counts for six particle sizes, and formaldehyde and other Top 20 VOC concentrations were measured in multiple zones. The testing showed that single-point exhaust ventilation was inferior as a whole-house ventilation strategy. It was inferior because the source of outside air was not direct from outside, themore » ventilation air was not distributed, and no provision existed for air filtration. Indoor air recirculation by a central air distribution system can help improve the exhaust ventilation system by way of air mixing and filtration. In contrast, the supply and balanced ventilation systems showed that there is a significant benefit to drawing outside air from a known outside location, and filtering and distributing that air. Compared to the Exhaust systems, the CFIS and ERV systems showed better ventilation air distribution and lower concentrations of particulates, formaldehyde and other VOCs. System improvement percentages were estimated based on four System Factor Categories: Balance, Distribution, Outside Air Source, and Recirculation Filtration. Recommended System Factors could be applied to reduce ventilation fan airflow rates relative to ASHRAE Standard 62.2 to save energy and reduce moisture control risk in humid climates. HVAC energy savings were predicted to be 8-10%, or $50-$75/year.« less

  10. Functional differences in bi-level pressure preset ventilators.

    PubMed

    Highcock, M P; Shneerson, J M; Smith, I E

    2001-02-01

    The performance of four bilevel positive pressure preset ventilators was compared. The ventilators tested were; BiPAP ST30 (Respironics); Nippy2 (B + D Electrical); Quantum PSV (Healthdyne); and Sullivan VPAP H ST (Resmed). A patient simulator was used to determine the sensitivity of the triggering mechanisms and the responses to a leak within the patient circuit, and to changes in patient effort. Significant differences (p <0.05) between the devices were seen in the trigger delay time and inspiratory trigger pressure. When a leak was introduced into the patient circuit, the fall in tidal volume (VT) was less than ten per cent for each ventilator. The addition of patient effort produced a number of changes in the ventilation delivered. Patient efforts of 0.25 s induced a variable fall in VT. An increase in VT was seen with some ventilators with patient efforts of 1 s but the effect was variable. Trigger failures and subsequent falls in minute volume were seen with the BiPAP and the Nippy2 at the highest respiratory frequency. Differences in the responses of the ventilators are demonstrated that may influence the selection of a ventilator, particularly in the treatment of breathless patients with ventilatory failure.

  11. Ventilation and infiltration in high-rise apartment buildings

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

    Diamond, R.C.; Feustel, H.E.; Dickerhoff, D.J.

    1996-03-01

    Air flow, air leakage measurements and numerical simulations were made on a 13-story apartment building to characterize the ventilation rates for the individual apartments. Parametric simulations were performed for specific conditions, e.g., height, orientation, outside temperature and wind speed. Our analysis of the air flow simulations suggest that the ventilation to the individual units varies considerably. With the mechanical ventilation system disabled and no wind, units at the lower level of the building have adequate ventilation only on days with high temperature differences, while units on higher floors have no ventilation at all. Units facing the windward side will bemore » over-ventilated when the building experiences wind directions between west and north. At the same time, leeward apartments did not experience any fresh air-because, in these cases, air flows enter the apartments from the corridor and exit through the exhaust shafts and the cracks in the facade. Even with the mechanical ventilation system operating, we found wide variation in the air flows to the individual apartments. In addition to the specific case presented here, these findings have more general implications for energy retrofits and health and comfort of occupants in high-rise apartment buildings.« less

  12. Characterization of natural ventilation in wastewater collection systems.

    PubMed

    Ward, Matthew; Corsi, Richard; Morton, Robert; Knapp, Tom; Apgar, Dirk; Quigley, Chris; Easter, Chris; Witherspoon, Jay; Pramanik, Amit; Parker, Wayne

    2011-03-01

    The purpose of the study was to characterize natural ventilation in full-scale gravity collection system components while measuring other parameters related to ventilation. Experiments were completed at four different locations in the wastewater collection systems of Los Angeles County Sanitation Districts, Los Angeles, California, and the King County Wastewater Treatment District, Seattle, Washington. The subject components were concrete gravity pipes ranging in diameter from 0.8 to 2.4 m (33 to 96 in.). Air velocity was measured in each pipe using a carbon-monoxide pulse tracer method. Air velocity was measured entering or exiting the components at vents using a standpipe and hotwire anemometer arrangement. Ambient wind speed, temperature, and relative humidity; headspace temperature and relative humidity; and wastewater flow and temperature were measured. The field experiments resulted in a large database of measured ventilation and related parameters characterizing ventilation in full-scale gravity sewers. Measured ventilation rates ranged from 23 to 840 L/s. The experimental data was used to evaluate existing ventilation models. Three models that were based upon empirical extrapolation, computational fluid dynamics, and thermodynamics, respectively, were evaluated based on predictive accuracy compared to the measured data. Strengths and weaknesses in each model were found and these observations were used to propose a concept for an improved ventilation model.

  13. 46 CFR 58.01-45 - Machinery space, ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Machinery space, ventilation. 58.01-45 Section 58.01-45... MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-45 Machinery space, ventilation. Each machinery space must be ventilated to ensure that, when machinery or boilers are operating at full power in all...

  14. 46 CFR 58.01-45 - Machinery space, ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Machinery space, ventilation. 58.01-45 Section 58.01-45... MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-45 Machinery space, ventilation. Each machinery space must be ventilated to ensure that, when machinery or boilers are operating at full power in all...

  15. 46 CFR 58.01-45 - Machinery space, ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Machinery space, ventilation. 58.01-45 Section 58.01-45... MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-45 Machinery space, ventilation. Each machinery space must be ventilated to ensure that, when machinery or boilers are operating at full power in all...

  16. 46 CFR 58.01-45 - Machinery space, ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Machinery space, ventilation. 58.01-45 Section 58.01-45... MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-45 Machinery space, ventilation. Each machinery space must be ventilated to ensure that, when machinery or boilers are operating at full power in all...

  17. 46 CFR 58.01-45 - Machinery space, ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Machinery space, ventilation. 58.01-45 Section 58.01-45... MACHINERY AND RELATED SYSTEMS General Requirements § 58.01-45 Machinery space, ventilation. Each machinery space must be ventilated to ensure that, when machinery or boilers are operating at full power in all...

  18. Protective lung ventilation in operating room: a systematic review.

    PubMed

    Futier, E; Constantin, J M; Jaber, S

    2014-06-01

    Postoperative pulmonary and extrapulmonary complications adversely affect clinical outcomes and healthcare utilization, so that prevention has become a measure of the quality of perioperative care. Mechanical ventilation is an essential support therapy to maintain adequate gas exchange during general anesthesia for surgery. Mechanical ventilation using high tidal volume (VT) (between 10 and 15 mL/kg) has been historically encouraged to prevent hypoxemia and atelectasis formation in anesthetized patients undergoing abdominal and thoracic surgery. However, there is accumulating evidence from both experimental and clinical studies that mechanical ventilation, especially the use of high VT and plateau pressure, may potentially aggravate or even initiate lung injury. Ventilator-associated lung injury can result from cyclic alveolar overdistension of non-dependent lung tissue, and repetitive opening and closing of dependent lung tissue resulting in ultrastructural damage at the junction of closed and open alveoli. Lung-protective ventilation, which refers to the use of lower VT and limited plateau pressure to minimize overdistension, and positive end-expiratory pressure to prevent alveolar collapse at end-expiration, was shown to improve outcome in critically ill patients with acute respiratory distress syndrome (ARDS). It has been recently suggested that this approach might also be beneficial in a broader population, especially in critically ill patients without ARDS at the onset of mechanical ventilation. There is, however, little evidence regarding a potential beneficial effect of lung protective ventilation during surgery, especially in patients with healthy lungs. Although surgical patients are frequently exposed to much shorter periods of mechanical ventilation, this is an important gap in knowledge given the number of patients receiving mechanical ventilation in the operating room. This review developed the benefits of lung protective ventilation during surgery

  19. 14 CFR 252.9 - Ventilation systems.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Ventilation systems. 252.9 Section 252.9 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking whenever...

  20. 14 CFR 252.9 - Ventilation systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Ventilation systems. 252.9 Section 252.9 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking whenever...

  1. 14 CFR 252.9 - Ventilation systems.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Ventilation systems. 252.9 Section 252.9 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking whenever...

  2. 14 CFR 252.9 - Ventilation systems.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Ventilation systems. 252.9 Section 252.9 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking whenever...

  3. 14 CFR 252.9 - Ventilation systems.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Ventilation systems. 252.9 Section 252.9 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.9 Ventilation systems. Air carriers shall prohibit smoking whenever...

  4. SY Tank Farm ventilation isolation option risk assessment report

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

    Powers, T.B.; Morales, S.D.

    The safety of the 241-SY Tank Farm ventilation system has been under extensive scrutiny due to safety concerns associated with tank 101-SY. Hydrogen and other gases are generated and trapped in the waste below the liquid surface. Periodically, these gases are released into the dome space and vented through the exhaust system. This attention to the ventilation system has resulted in the development of several alternative ventilation system designs. The ventilation system provides the primary means of mitigation of accidents associated with flammable gases. This report provides an assessment of various alternatives ventilation system designs.

  5. Design and calibration of a high-frequency oscillatory ventilator.

    PubMed

    Simon, B A; Mitzner, W

    1991-02-01

    High-frequency ventilation (HFV) is a modality of mechanical ventilation which presents difficult technical demands to the clinical or laboratory investigator. The essential features of an ideal HFV system are described, including wide frequency range, control of tidal volume and mean airway pressure, minimal dead space, and high effective internal impedance. The design and performance of a high-frequency oscillatory ventilation system is described which approaches these requirements. The ventilator utilizes a linear motor regulated by a closed loop controller and driving a novel frictionless double-diaphragm piston pump. Finally, the ventilator performance is tested using the impedance model of Venegas [1].

  6. Football Equipment Removal Improves Chest Compression and Ventilation Efficacy.

    PubMed

    Mihalik, Jason P; Lynall, Robert C; Fraser, Melissa A; Decoster, Laura C; De Maio, Valerie J; Patel, Amar P; Swartz, Erik E

    2016-01-01

    Airway access recommendations in potential catastrophic spine injury scenarios advocate for facemask removal, while keeping the helmet and shoulder pads in place for ensuing emergency transport. The anecdotal evidence to support these recommendations assumes that maintaining the helmet and shoulder pads assists inline cervical stabilization and that facial access guarantees adequate airway access. Our objective was to determine the effect of football equipment interference on performing chest compressions and delivering adequate ventilations on patient simulators. We hypothesized that conditions with more football equipment would decrease chest compression and ventilation efficacy. Thirty-two certified athletic trainers were block randomized to participate in six different compression conditions and six different ventilation conditions using human patient simulators. Data for chest compression (mean compression depth, compression rate, percentage of correctly released compressions, and percentage of adequate compressions) and ventilation (total ventilations, mean ventilation volume, and percentage of ventilations delivering adequate volume) conditions were analyzed across all conditions. The fully equipped athlete resulted in the lowest mean compression depth (F5,154 = 22.82; P < 0.001; Effect Size = 0.98) and delivery of adequate compressions (F5,154 = 15.06; P < 0.001; Effect Size = 1.09) compared to all other conditions. Bag-valve mask conditions resulted in delivery of significantly higher mean ventilation volumes compared to all 1- or 2-person pocketmask conditions (F5,150 = 40.05; P < 0.001; Effect Size = 1.47). Two-responder ventilation scenarios resulted in delivery of a greater number of total ventilations (F5,153 = 3.99; P = 0.002; Effect Size = 0.26) and percentage of adequate ventilations (F5,150 = 5.44; P < 0.001; Effect Size = 0.89) compared to one-responder scenarios. Non-chinstrap conditions permitted greater ventilation volumes (F3,28 = 35.17; P

  7. 30 CFR 36.45 - Quantity of ventilating air.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Quantity of ventilating air. 36.45 Section 36... TRANSPORTATION EQUIPMENT Test Requirements § 36.45 Quantity of ventilating air. (a) Results of the engine tests shall be used to calculate ventilation (cubic feet of air per minute) that shall be supplied by positive...

  8. 30 CFR 75.350 - Belt air course ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Belt air course ventilation. 75.350 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.350 Belt air course ventilation. (a) The belt air course must not be used as a return air course; and except as provided in paragraph...

  9. 30 CFR 36.45 - Quantity of ventilating air.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Quantity of ventilating air. 36.45 Section 36... TRANSPORTATION EQUIPMENT Test Requirements § 36.45 Quantity of ventilating air. (a) Results of the engine tests shall be used to calculate ventilation (cubic feet of air per minute) that shall be supplied by positive...

  10. 30 CFR 75.350 - Belt air course ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Belt air course ventilation. 75.350 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.350 Belt air course ventilation. (a) The belt air course must not be used as a return air course; and except as provided in paragraph...

  11. 30 CFR 36.45 - Quantity of ventilating air.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Quantity of ventilating air. 36.45 Section 36... TRANSPORTATION EQUIPMENT Test Requirements § 36.45 Quantity of ventilating air. (a) Results of the engine tests shall be used to calculate ventilation (cubic feet of air per minute) that shall be supplied by positive...

  12. 30 CFR 75.350 - Belt air course ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Belt air course ventilation. 75.350 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.350 Belt air course ventilation. (a) The belt air course must not be used as a return air course; and except as provided in paragraph...

  13. 30 CFR 75.350 - Belt air course ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Belt air course ventilation. 75.350 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.350 Belt air course ventilation. (a) The belt air course must not be used as a return air course; and except as provided in paragraph...

  14. [Pulmonary complications associated with mechanical ventilation in neonates].

    PubMed

    Torres-Castro, Cristabel; Valle-Leal, Jaime; Martínez-Limón, Alba J; Lastra-Jiménez, Zaira; Delgado-Bojórquez, Lesvia Carmina

    To determine the incidence of0 associated with mechanical ventilation in patients admitted to a service in a second level hospital NICU. Retrospective analytical study records of newborns admitted to NICU room and receiving mechanical ventilation in a secondary hospital health care. Demographic data, of mechanical ventilation, intubation and complications reported in the clinical record were collected and analyzed in SPSS 20. 53 patients selected a total of 40 complications found. The annual incidence of pulmonary complications associated with mechanical ventilation in the area of service neonatology NICU, at a second level hospital at Sonora was 49.05% (95% CI 0.35 to 0.62). The most frequent pulmonary complications were atelectasis 35%, pneumonia 27.5%, pneumothorax 15%, bronchopulmonary dysplasia 15%, pneumomediastinum 15% and pulmonary hemorrhage 2.5%. The presentation of pulmonary complications secondary to mechanical ventilation in neonatal patients is similar to that reported in developing countries. Atelectasis is the most common pulmonary complication in neonatal patients undergoing mechanical ventilation. Copyright © 2016 Hospital Infantil de México Federico Gómez. Publicado por Masson Doyma México S.A. All rights reserved.

  15. 46 CFR 153.310 - Ventilation system type.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Handling Space Ventilation § 153.310 Ventilation system type. A cargo handling space must have a permanent...

  16. 46 CFR 153.310 - Ventilation system type.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Handling Space Ventilation § 153.310 Ventilation system type. A cargo handling space must have a permanent...

  17. 46 CFR 153.310 - Ventilation system type.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Handling Space Ventilation § 153.310 Ventilation system type. A cargo handling space must have a permanent...

  18. 46 CFR 153.310 - Ventilation system type.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Handling Space Ventilation § 153.310 Ventilation system type. A cargo handling space must have a permanent...

  19. 46 CFR 153.310 - Ventilation system type.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Handling Space Ventilation § 153.310 Ventilation system type. A cargo handling space must have a permanent...

  20. Multifaceted bench comparative evaluation of latest intensive care unit ventilators.

    PubMed

    Garnier, M; Quesnel, C; Fulgencio, J-P; Degrain, M; Carteaux, G; Bonnet, F; Similowski, T; Demoule, A

    2015-07-01

    Independent bench studies using specific ventilation scenarios allow testing of the performance of ventilators in conditions similar to clinical settings. The aims of this study were to determine the accuracy of the latest generation ventilators to deliver chosen parameters in various typical conditions and to provide clinicians with a comprehensive report on their performance. Thirteen modern intensive care unit ventilators were evaluated on the ASL5000 test lung with and without leakage for: (i) accuracy to deliver exact tidal volume (VT) and PEEP in assist-control ventilation (ACV); (ii) performance of trigger and pressurization in pressure support ventilation (PSV); and (iii) quality of non-invasive ventilation algorithms. In ACV, only six ventilators delivered an accurate VT and nine an accurate PEEP. Eleven devices failed to compensate VT and four the PEEP in leakage conditions. Inspiratory delays differed significantly among ventilators in invasive PSV (range 75-149 ms, P=0.03) and non-invasive PSV (range 78-165 ms, P<0.001). The percentage of the ideal curve (concomitantly evaluating the pressurization speed and the levels of pressure reached) also differed significantly (range 57-86% for invasive PSV, P=0.04; and 60-90% for non-invasive PSV, P<0.001). Non-invasive ventilation algorithms efficiently prevented the decrease in pressurization capacities and PEEP levels induced by leaks in, respectively, 10 and 12 out of the 13 ventilators. We observed real heterogeneity of performance amongst the latest generation of intensive care unit ventilators. Although non-invasive ventilation algorithms appear to maintain adequate pressurization efficiently in the case of leakage, basic functions, such as delivered VT in ACV and pressurization in PSV, are often less reliable than the values displayed by the device suggest. © The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions

  1. Increasing the inspiratory time and I:E ratio during mechanical ventilation aggravates ventilator-induced lung injury in mice.

    PubMed

    Müller-Redetzky, Holger C; Felten, Matthias; Hellwig, Katharina; Wienhold, Sandra-Maria; Naujoks, Jan; Opitz, Bastian; Kershaw, Olivia; Gruber, Achim D; Suttorp, Norbert; Witzenrath, Martin

    2015-01-28

    Lung-protective ventilation reduced acute respiratory distress syndrome (ARDS) mortality. To minimize ventilator-induced lung injury (VILI), tidal volume is limited, high plateau pressures are avoided, and positive end-expiratory pressure (PEEP) is applied. However, the impact of specific ventilatory patterns on VILI is not well defined. Increasing inspiratory time and thereby the inspiratory/expiratory ratio (I:E ratio) may improve oxygenation, but may also be harmful as the absolute stress and strain over time increase. We thus hypothesized that increasing inspiratory time and I:E ratio aggravates VILI. VILI was induced in mice by high tidal-volume ventilation (HVT 34 ml/kg). Low tidal-volume ventilation (LVT 9 ml/kg) was used in control groups. PEEP was set to 2 cm H2O, FiO2 was 0.5 in all groups. HVT and LVT mice were ventilated with either I:E of 1:2 (LVT 1:2, HVT 1:2) or 1:1 (LVT 1:1, HVT 1:1) for 4 hours or until an alternative end point, defined as mean arterial blood pressure below 40 mm Hg. Dynamic hyperinflation due to the increased I:E ratio was excluded in a separate group of animals. Survival, lung compliance, oxygenation, pulmonary permeability, markers of pulmonary and systemic inflammation (leukocyte differentiation in lung and blood, analyses of pulmonary interleukin-6, interleukin-1β, keratinocyte-derived chemokine, monocyte chemoattractant protein-1), and histopathologic pulmonary changes were analyzed. LVT 1:2 or LVT 1:1 did not result in VILI, and all individuals survived the ventilation period. HVT 1:2 decreased lung compliance, increased pulmonary neutrophils and cytokine expression, and evoked marked histologic signs of lung injury. All animals survived. HVT 1:1 caused further significant worsening of oxygenation, compliance and increased pulmonary proinflammatory cytokine expression, and pulmonary and blood neutrophils. In the HVT 1:1 group, significant mortality during mechanical ventilation was observed. According to the "baby lung

  2. Rationale and design of the Atrial Fibrillation health Literacy Information Technology Trial: (AF-LITT).

    PubMed

    Guhl, Emily N; Schlusser, Courtney L; Henault, Lori E; Bickmore, Timothy W; Kimani, Everlyne; Paasche-Orlow, Michael K; Magnani, Jared W

    2017-11-01

    Atrial Fibrillation (AF) is a common cardiac arrhythmia that is challenging for patients and adversely impacts health-related quality of life (HRQoL). Long-term management of AF requires that patients adhere to complex therapies, understand difficult terminology, navigate subspecialty care, and have continued symptom monitoring with the goal of preventing adverse outcomes. Continued interventions to ameliorate the patient experience of AF are essential. The Atrial Fibrillation health Literacy Information Technology Trial (AF-LITT; NCT03093558) is an investigator-initiated, 2-arm randomized clinical trial (RCT). This RCT is a pilot in order to implement a novel, smartphone-based intervention to address the patient experience of AF. This pilot RCT will compare a combination of the Embodied Conversational Agent (ECA) and the Alive Cor Kardia Mobile heart rhythm monitor to the current standard of care. The study will enroll 180 adults with non-valvular AF who are receiving anticoagulation for stroke prevention and randomize them to receive a 30-day intervention (smartphone-based ECA/Kardia) or standard of care, which will include a symptom and adherence journal. The primary end-points are improvement in HRQoL and self-reported adherence to anticoagulation. The secondary end-points are the acceptability of the intervention to participants, its use by participants, and acceptability to referring physicians. The AF-LITT pilot aims to evaluate the efficacy of the ECA/Kardia to improve HRQoL and anticoagulant adherence, and to guide its implementation in a larger, multicenter clinical trial. The intervention has potential to improve HRQoL, adherence, and health care utilization in individuals with chronic AF. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Rationale and design of the Atrial Fibrillation health Literacy Information Technology Trial: (AF-LITT)

    PubMed Central

    Guhl, Emily N.; Schlusser, Courtney L.; Henault, Lori E.; Bickmore, Timothy W.; Kimani, Everlyne; Paasche-Orlow, Michael K.; Magnani, Jared W.

    2017-01-01

    Background Atrial Fibrillation (AF) is a common cardiac arrhythmia that is challenging for patients and adversely impacts health-related quality of life (HRQoL). Long-term management of AF requires that patients adhere to complex therapies, understand difficult terminology, navigate subspecialty care, and have continued symptom monitoring with the goal of preventing adverse outcomes. Continued interventions to ameliorate the patient experience of AF are essential. Design The Atrial Fibrillation health Literacy Information Technology Trial (AF-LITT; NCT03093558) is an investigator-initiated, 2-arm randomized clinical trial (RCT). This RCT is a pilot in order to implement a novel, smartphone-based intervention to address the patient experience of AF. This pilot RCT will compare a combination of the embodied conversational agent (ECA) and the Alive Cor Kardia Mobile heart rhythm monitor to the current standard of care. The study will enroll 180 adults with non-valvular AF who are receiving anticoagulation for stroke prevention and randomize them to receive a 30-day intervention (smartphone-based ECA/Kardia) or standard of care, which will include a symptom and adherence journal. The primary end-points are improvement in HRQoL and self-reported adherence to anticoagulation. The secondary end-points are the acceptability of the intervention to participants, its use by participants, and acceptability to referring physicians. Conclusions The AF-LITT pilot aims to evaluate the efficacy of the ECA/Kardia to improve HRQoL and anticoagulant adherence, and to guide its implementation in a larger, multicenter clinical trial. The intervention has potential to improve HRQoL, adherence, and health care utilization in individuals with chronic AF. PMID:28923492

  4. Ventilation-perfusion distribution in normal subjects.

    PubMed

    Beck, Kenneth C; Johnson, Bruce D; Olson, Thomas P; Wilson, Theodore A

    2012-09-01

    Functional values of LogSD of the ventilation distribution (σ(V)) have been reported previously, but functional values of LogSD of the perfusion distribution (σ(q)) and the coefficient of correlation between ventilation and perfusion (ρ) have not been measured in humans. Here, we report values for σ(V), σ(q), and ρ obtained from wash-in data for three gases, helium and two soluble gases, acetylene and dimethyl ether. Normal subjects inspired gas containing the test gases, and the concentrations of the gases at end-expiration during the first 10 breaths were measured with the subjects at rest and at increasing levels of exercise. The regional distribution of ventilation and perfusion was described by a bivariate log-normal distribution with parameters σ(V), σ(q), and ρ, and these parameters were evaluated by matching the values of expired gas concentrations calculated for this distribution to the measured values. Values of cardiac output and LogSD ventilation/perfusion (Va/Q) were obtained. At rest, σ(q) is high (1.08 ± 0.12). With the onset of ventilation, σ(q) decreases to 0.85 ± 0.09 but remains higher than σ(V) (0.43 ± 0.09) at all exercise levels. Rho increases to 0.87 ± 0.07, and the value of LogSD Va/Q for light and moderate exercise is primarily the result of the difference between the magnitudes of σ(q) and σ(V). With known values for the parameters, the bivariate distribution describes the comprehensive distribution of ventilation and perfusion that underlies the distribution of the Va/Q ratio.

  5. 46 CFR 97.37-50 - Ventilation alarm failure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Ventilation alarm failure. 97.37-50 Section 97.37-50... OPERATIONS Markings for Fire and Emergency Equipment, Etc. § 97.37-50 Ventilation alarm failure. (a) The...-inch letters “VENTILATION FAILURE IN VEHICULAR SPACE.” (b) [Reserved] [CGFR 66-33, 31 FR 15286, Dec. 6...

  6. 46 CFR 97.37-50 - Ventilation alarm failure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Ventilation alarm failure. 97.37-50 Section 97.37-50... OPERATIONS Markings for Fire and Emergency Equipment, Etc. § 97.37-50 Ventilation alarm failure. (a) The...-inch letters “VENTILATION FAILURE IN VEHICULAR SPACE.” (b) [Reserved] [CGFR 66-33, 31 FR 15286, Dec. 6...

  7. 46 CFR 97.37-50 - Ventilation alarm failure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Ventilation alarm failure. 97.37-50 Section 97.37-50... OPERATIONS Markings for Fire and Emergency Equipment, Etc. § 97.37-50 Ventilation alarm failure. (a) The...-inch letters “VENTILATION FAILURE IN VEHICULAR SPACE.” (b) [Reserved] [CGFR 66-33, 31 FR 15286, Dec. 6...

  8. 46 CFR 97.37-50 - Ventilation alarm failure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Ventilation alarm failure. 97.37-50 Section 97.37-50... OPERATIONS Markings for Fire and Emergency Equipment, Etc. § 97.37-50 Ventilation alarm failure. (a) The...-inch letters “VENTILATION FAILURE IN VEHICULAR SPACE.” (b) [Reserved] [CGFR 66-33, 31 FR 15286, Dec. 6...

  9. Effect of Ventilation Strategies on Residential Ozone Levels

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

    Walker, Iain S.; Sherman, Max H.

    Elevated outdoor ozone levels are associated with adverse health effects. Because people spend the vast majority of their time indoors, reduction in indoor levels of ozone of outdoor origin would lower population exposures and might also lead to a reduction in ozone-associated adverse health effects. In most buildings, indoor ozone levels are diminished with respect to outdoor levels to an extent that depends on surface reactions and on the degree to which ozone penetrates the building envelope. Ozone enters buildings from outdoors together with the airflows that are driven by natural and mechanical means, including deliberate ventilation used to reducemore » concentrations of indoor-generated pollutants. When assessing the effect of deliberate ventilation on occupant health one should consider not only the positive effects on removing pollutants of indoor origin but also the possibility that enhanced ventilation might increase indoor levels of pollutants originating outdoors. This study considers how changes in residential ventilation that are designed to comply with ASHRAE Standard 62.2 might influence indoor levels of ozone. Simulation results show that the building envelope can contribute significantly to filtration of ozone. Consequently, the use of exhaust ventilation systems is predicted to produce lower indoor ozone concentrations than would occur with balanced ventilation systems operating at the same air-­exchange rate. We also investigated a strategy for reducing exposure to ozone that would deliberately reduce ventilation rates during times of high outdoor ozone concentration while still meeting daily average ventilation requirements.« less

  10. Elective ventilation for organ donation: law, policy and public ethics.

    PubMed

    Coggon, John

    2013-03-01

    This paper examines questions concerning elective ventilation, contextualised within English law and policy. It presents the general debate with reference both to the Exeter Protocol on elective ventilation, and the considerable developments in legal principle since the time that that protocol was declared to be unlawful. I distinguish different aspects of what might be labelled elective ventilation policies under the following four headings: 'basic elective ventilation'; 'epistemically complex elective ventilation'; 'practically complex elective ventilation'; and 'epistemically and practically complex elective ventilation'. I give a legal analysis of each. In concluding remarks on their potential practical viability, I emphasise the importance not just of ascertaining the legal and ethical acceptability of these and other forms of elective ventilation, but also of assessing their professional and political acceptability. This importance relates both to the successful implementation of the individual practices, and to guarding against possible harmful effects in the wider efforts to increase the rates of posthumous organ donation.

  11. Pretest Predictions for Phase II Ventilation Tests

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

    Yiming Sun

    The objective of this calculation is to predict the temperatures of the ventilating air, waste package surface, and concrete pipe walls that will be developed during the Phase II ventilation tests involving various test conditions. The results will be used as inputs to validating numerical approach for modeling continuous ventilation, and be used to support the repository subsurface design. The scope of the calculation is to identify the physical mechanisms and parameters related to thermal response in the Phase II ventilation tests, and describe numerical methods that are used to calculate the effects of continuous ventilation. The calculation is limitedmore » to thermal effect only. This engineering work activity is conducted in accordance with the ''Technical Work Plan for: Subsurface Performance Testing for License Application (LA) for Fiscal Year 2001'' (CRWMS M&O 2000d). This technical work plan (TWP) includes an AP-2.21Q, ''Quality Determinations and Planning for Scientific, Engineering, and Regulatory Compliance Activities'', activity evaluation (CRWMS M&O 2000d, Addendum A) that has determined this activity is subject to the YMP quality assurance (QA) program. The calculation is developed in accordance with the AP-3.12Q procedure, ''Calculations''. Additional background information regarding this activity is contained in the ''Development Plan for Ventilation Pretest Predictive Calculation'' (DP) (CRWMS M&O 2000a).« less

  12. Ventilation System Effectiveness and Tested Indoor Air Quality Impacts

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

    Rudd, Armin; Bergey, Daniel

    In this project, Building America research team Building Science Corporation tested the effectiveness of ventilation systems at two unoccupied, single-family, detached lab homes at the University of Texas - Tyler. Five ventilation system tests were conducted with various whole-building ventilation systems. Multizone fan pressurization testing characterized building and zone enclosure leakage. PFT testing showed multizone air change rates and interzonal airflow. Cumulative particle counts for six particle sizes, and formaldehyde and other Top 20 VOC concentrations were measured in multiple zones. The testing showed that single-point exhaust ventilation was inferior as a whole-house ventilation strategy. This was because the sourcemore » of outside air was not direct from outside, the ventilation air was not distributed, and no provision existed for air filtration. Indoor air recirculation by a central air distribution system can help improve the exhaust ventilation system by way of air mixing and filtration. In contrast, the supply and balanced ventilation systems showed that there is a significant benefit to drawing outside air from a known outside location, and filtering and distributing that air. Compared to the exhaust systems, the CFIS and ERV systems showed better ventilation air distribution and lower concentrations of particulates, formaldehyde and other VOCs. System improvement percentages were estimated based on four system factor categories: balance, distribution, outside air source, and recirculation filtration. Recommended system factors could be applied to reduce ventilation fan airflow rates relative to ASHRAE Standard 62.2 to save energy and reduce moisture control risk in humid climates. HVAC energy savings were predicted to be 8-10%, or $50-$75/year.« less

  13. Incidence and economic burden of suspected adverse events and adverse event monitoring during AF therapy.

    PubMed

    Kim, M H; Lin, J; Hussein, M; Battleman, D

    2009-12-01

    Rhythm- and rate-control therapies are an essential part of atrial fibrillation (AF) management; however, the use of existing agents is often limited by the occurrence of adverse events. The aim of this study was to evaluate suspected adverse events and adverse event monitoring, and associated medical costs, in patients receiving AF rhythm-control and/or rate-control therapy. This retrospective cohort study used claims data from the Integrated Healthcare Information Systems National Managed Care Benchmark Database from 2002-2006. Patients hospitalized for AF (primary diagnosis), and who had at least 365 days' enrollment before and after the initial (index) AF hospitalization, were included in the analysis. Suspected AF therapy-related adverse events and function tests for adverse event monitoring were identified according to pre-specified diagnosis codes/procedures, and examined over the 12 months following discharge from the index hospitalization. Events/function tests had to have occurred within 90 days of a claim for AF therapy to be considered a suspected adverse event/adverse event monitoring. Of 4174 AF patients meeting the study criteria, 3323 received AF drugs; 428 received rhythm-control only (12.9%), 2130 rate-control only (64.1%), and 765 combined rhythm/rate-control therapy (23.0%). Overall, 50.1% of treated patients had a suspected adverse event and/or function test for adverse event monitoring (45.5% with rate-control, 53.5% with rhythm-control, and 61.2% with combined rhythm/rate-control). Suspected cardiovascular adverse events were the most common events (occurring in 36.1% of patients), followed by pulmonary (6.1%), and endocrine events (5.9%). Overall, suspected adverse events/function tests were associated with mean annual per-patient costs of $3089 ($1750 with rhythm-control, $2041 with rate control, and $6755 with combined rhythm/rate-control). As a retrospective analysis, the study is subject to potential selection bias, while its reliance on

  14. Regenerative Blower for EVA Suit Ventilation Fan

    NASA Technical Reports Server (NTRS)

    Izenson, Michael G.; Chen, Weibo; Paul, Heather L.

    2010-01-01

    Portable life support systems in future space suits will include a ventilation subsystem driven by a dedicated fan. This ventilation fan must meet challenging requirements for pressure rise, flow rate, efficiency, size, safety, and reliability. This paper describes research and development that showed the feasibility of a regenerative blower that is uniquely suited to meet these requirements. We proved feasibility through component tests, blower tests, and design analysis. Based on the requirements for the Constellation Space Suit Element (CSSE) Portable Life Support System (PLSS) ventilation fan, we designed the critical elements of the blower. We measured the effects of key design parameters on blower performance using separate effects tests, and used the results of these tests to design a regenerative blower that will meet the ventilation fan requirements. We assembled a proof-of-concept blower and measured its performance at sub-atmospheric pressures that simulate a PLSS ventilation loop environment. Head/flow performance and maximum efficiency point data were used to specify the design and operating conditions for the ventilation fan. We identified materials for the blower that will enhance safety for operation in a lunar environment, and produced a solid model that illustrates the final design. The proof-of-concept blower produced the flow rate and pressure rise needed for the CSSE ventilation subsystem while running at 5400 rpm, consuming only 9 W of electric power using a non-optimized, commercial motor and controller and inefficient bearings. Scaling the test results to a complete design shows that a lightweight, compact, reliable, and low power regenerative blower can meet the performance requirements for future space suit life support systems.

  15. Functional characterization of the copper transcription factor AfMac1 from Aspergillus fumigatus.

    PubMed

    Park, Yong-Sung; Kim, Tae-Hyoung; Yun, Cheol-Won

    2017-07-03

    Although copper functions as a cofactor in many physiological processes, copper overload leads to harmful effects in living cells. Thus, copper homeostasis is tightly regulated. However, detailed copper metabolic pathways have not yet been identified in filamentous fungi. In this report, we investigated the copper transcription factor AfMac1 ( A spergillus f umigatus Mac1 homolog) and identified its regulatory mechanism in A. fumigatus AfMac1 has domains homologous to the DNA-binding and copper-binding domains of Mac1 from Saccharomyces cerevisiae , and AfMac1 efficiently complemented Mac1 in S. cerevisiae Expression of Afmac1 resulted in CTR1 up-regulation, and mutation of the DNA-binding domain of Afmac1 failed to activate CTR1 expression in S. cerevisiae The Afmac1 deletion strain of A. fumigatus failed to grow in copper-limited media, and its growth was restored by introducing ctrC We found that AfMac1 specifically bound to the promoter region of ctrC based on EMSA. The AfMac1-binding motif 5'-TGTGCTCA-3' was identified from the promoter region of ctrC , and the addition of mutant ctrC lacking the AfMac1-binding motif failed to up-regulate ctrC in A. fumigatus Furthermore, deletion of Afmac1 significantly reduced strain virulence and activated conidial killing activity by neutrophils and macrophages. Taken together, these results suggest that AfMac1 is a copper transcription factor that regulates cellular copper homeostasis in A. fumigatus . © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

  16. Simultaneous adsorption of Cu2+ and Acid fuchsin (AF) from aqueous solutions by CMC/bentonite composite.

    PubMed

    Gong, Ning; Liu, Yanping; Huang, Ruihua

    2018-04-21

    Carboxymethyl-chitosan (CMC)/bentonite composite was prepared by the method of membrane-forming, and characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) techniques. The simultaneous adsorption of Cu 2+ and Acid fuchsin (AF) applying CMC/bentonite composite as an adsorbent in single or binary systems was investigated. The adsorption study was conducted systematically by varying the ratio of CMC to bentonite, adsorbent dosage, initial pH value, initial Cu 2+ (or AF) concentration, contact time and the interaction of two components in binary solutions. The results showed that the presence of Cu 2+ hindered the adsorption of AF, while the presence of AF almost had no influence on the adsorption of Cu 2+ in binary systems. The adsorption data of Cu 2+ and AF were both suitable for Langmuir isotherm model, and the maximum adsorption capacities of CMC/bentonite composite, according to the Langmuir isotherm model were 81.4 mg/g for Cu 2+ and 253.2 mg/g for AF at 298 K. The pseudo-second-order model could better describe the adsorption process of Cu 2+ and AF. Thermodynamic constant values illustrated that the adsorption of Cu 2+ was endothermic, while the adsorption process of AF was exothermic. Copyright © 2018. Published by Elsevier B.V.

  17. The School Advanced Ventilation Engineering Software (SAVES)

    EPA Pesticide Factsheets

    The School Advanced Ventilation Engineering Software (SAVES) package is a tool to help school designers assess the potential financial payback and indoor humidity control benefits of Energy Recovery Ventilation (ERV) systems for school applications.

  18. Airway pressure release ventilation: what do we know?

    PubMed

    Daoud, Ehab G; Farag, Hany L; Chatburn, Robert L

    2012-02-01

    Airway pressure release ventilation (APRV) is inverse ratio, pressure controlled, intermittent mandatory ventilation with unrestricted spontaneous breathing. It is based on the principle of open lung approach. It has many purported advantages over conventional ventilation, including alveolar recruitment, improved oxygenation, preservation of spontaneous breathing, improved hemodynamics, and potential lung-protective effects. It has many claimed disadvantages related to risks of volutrauma, increased work of breathing, and increased energy expenditure related to spontaneous breathing. APRV is used mainly as a rescue therapy for the difficult to oxygenate patients with acute respiratory distress syndrome (ARDS). There is confusion regarding this mode of ventilation, due to the different terminology used in the literature. APRV settings include the "P high," "T high," "P low," and "T low". Physicians and respiratory therapists should be aware of the different ways and the rationales for setting these variables on the ventilators. Also, they should be familiar with the differences between APRV, biphasic positive airway pressure (BIPAP), and other conventional and nonconventional modes of ventilation. There is no solid proof that APRV improves mortality; however, there are ongoing studies that may reveal further information about this mode of ventilation. This paper reviews the different methods proposed for APRV settings, and summarizes the different studies comparing APRV and BIPAP, and the potential benefits and pitfalls for APRV.

  19. Humidification during high-frequency oscillation ventilation is affected by ventilator circuit and ventilatory setting.

    PubMed

    Chikata, Yusuke; Imanaka, Hideaki; Onishi, Yoshiaki; Ueta, Masahiko; Nishimura, Masaji

    2009-08-01

    High-frequency oscillation ventilation (HFOV) is an accepted ventilatory mode for acute respiratory failure in neonates. As conventional mechanical ventilation, inspiratory gas humidification is essential. However, humidification during HFOV has not been clarified. In this bench study, we evaluated humidification during HFOV in the open circumstance of ICU. Our hypothesis is that humidification during HFOV is affected by circuit design and ventilatory settings. We connected a ventilator with HFOV mode to a neonatal lung model that was placed in an infant incubator set at 37 degrees C. We set a heated humidifier (Fisher & Paykel) to obtain 37 degrees C at the chamber outlet and 40 degrees C at the distal temperature probe. We measured absolute humidity and temperature at the Y-piece using a rapid-response hygrometer. We evaluated two types of ventilator circuit: a circuit with inner heating wire and another with embedded heating element. In addition, we evaluated three lengths of the inspiratory limb, three stroke volumes, three frequencies, and three mean airway pressures. The circuit with embedded heating element provided significantly higher absolute humidity and temperature than one with inner heating wire. As an extended tube lacking a heating wire was shorter, absolute humidity and temperature became higher. In the circuit with inner heating wire, absolute humidity and temperature increased as stroke volume increased. Humidification during HFOV is affected by circuit design and ventilatory settings.

  20. Ventilation planning at Energy West's Deer Creek mine

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

    Tonc, L.; Prosser, B.; Gamble, G.

    2009-08-15

    In 2004 ventilation planning was initiated to exploit a remote area of Deer Creek mine's reserve (near Huntington, Utah), the Mill Fork Area, located under a mountain. A push-pull ventilation system was selected. This article details the design process of the ventilation system upgrade, the procurement process for the new fans, and the new fan startup testing. 5 figs., 1 photo.

  1. Significant Improvements in Pyranometer Nighttime Offsets Using High-Flow DC Ventilation

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

    Michalsky, Joseph J.; Kutchenreiter, Mark; Long, Charles N.

    Ventilators are used to keep the domes of pyranometers clean and dry, but they affect the nighttime offset as well. This paper examines different ventilation strategies. For the several commercial single-black-detector pyranometers with ventilators examined here, high flow rate (50 CFM and higher), 12 VDC fans lower the offsets, lower the scatter, and improve the predictability of the offsets during the night compared with lower flow rate 35 CFM, 120 VAC fans operated in the same ventilator housings. Black-and-white pyranometers sometimes show improvement with DC ventilation, but in some cases DC ventilation makes the offsets slightly worse. Since the offsetsmore » for these black-and-white pyranometers are always small, usually no more than 1 Wm -2, whether AC or DC ventilated, changing their ventilation to higher CFM DC ventilation is not imperative. Future work should include all major manufacturers of pyranometers and unventilated, as well as, ventilated pyranometers. Lastly, an important outcome of future research will be to clarify under what circumstances nighttime data can be used to predict daytime offsets.« less

  2. Significant Improvements in Pyranometer Nighttime Offsets Using High-Flow DC Ventilation

    DOE PAGES

    Michalsky, Joseph J.; Kutchenreiter, Mark; Long, Charles N.

    2017-06-20

    Ventilators are used to keep the domes of pyranometers clean and dry, but they affect the nighttime offset as well. This paper examines different ventilation strategies. For the several commercial single-black-detector pyranometers with ventilators examined here, high flow rate (50 CFM and higher), 12 VDC fans lower the offsets, lower the scatter, and improve the predictability of the offsets during the night compared with lower flow rate 35 CFM, 120 VAC fans operated in the same ventilator housings. Black-and-white pyranometers sometimes show improvement with DC ventilation, but in some cases DC ventilation makes the offsets slightly worse. Since the offsetsmore » for these black-and-white pyranometers are always small, usually no more than 1 Wm -2, whether AC or DC ventilated, changing their ventilation to higher CFM DC ventilation is not imperative. Future work should include all major manufacturers of pyranometers and unventilated, as well as, ventilated pyranometers. Lastly, an important outcome of future research will be to clarify under what circumstances nighttime data can be used to predict daytime offsets.« less

  3. Mechanical Ventilation

    MedlinePlus

    ... to stay in as long as needed. At times a person can talk with a trach tube in place by using a special adapter called a speaking valve . (For more information on having a tracheostomy see ATS patient information series at www. thoracic. org/ patients) . The ventilator blows ...

  4. Pulmonary Ventilation Imaging Based on 4-Dimensional Computed Tomography: Comparison With Pulmonary Function Tests and SPECT Ventilation Images

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

    Yamamoto, Tokihiro, E-mail: toyamamoto@ucdavis.edu; Department of Radiation Oncology, University of California Davis School of Medicine, Sacramento, California; Kabus, Sven

    Purpose: 4-dimensional computed tomography (4D-CT)-based pulmonary ventilation imaging is an emerging functional imaging modality. The purpose of this study was to investigate the physiological significance of 4D-CT ventilation imaging by comparison with pulmonary function test (PFT) measurements and single-photon emission CT (SPECT) ventilation images, which are the clinical references for global and regional lung function, respectively. Methods and Materials: In an institutional review board–approved prospective clinical trial, 4D-CT imaging and PFT and/or SPECT ventilation imaging were performed in thoracic cancer patients. Regional ventilation (V{sub 4DCT}) was calculated by deformable image registration of 4D-CT images and quantitative analysis for regional volumemore » change. V{sub 4DCT} defect parameters were compared with the PFT measurements (forced expiratory volume in 1 second (FEV{sub 1}; % predicted) and FEV{sub 1}/forced vital capacity (FVC; %). V{sub 4DCT} was also compared with SPECT ventilation (V{sub SPECT}) to (1) test whether V{sub 4DCT} in V{sub SPECT} defect regions is significantly lower than in nondefect regions by using the 2-tailed t test; (2) to quantify the spatial overlap between V{sub 4DCT} and V{sub SPECT} defect regions with Dice similarity coefficient (DSC); and (3) to test ventral-to-dorsal gradients by using the 2-tailed t test. Results: Of 21 patients enrolled in the study, 18 patients for whom 4D-CT and either PFT or SPECT were acquired were included in the analysis. V{sub 4DCT} defect parameters were found to have significant, moderate correlations with PFT measurements. For example, V{sub 4DCT}{sup HU} defect volume increased significantly with decreasing FEV{sub 1}/FVC (R=−0.65, P<.01). V{sub 4DCT} in V{sub SPECT} defect regions was significantly lower than in nondefect regions (mean V{sub 4DCT}{sup HU} 0.049 vs 0.076, P<.01). The average DSCs for the spatial overlap with SPECT ventilation defect regions were only

  5. AF-6 is a positive modulator of the PINK1/parkin pathway and is deficient in Parkinson's disease

    PubMed Central

    Haskin, Joseph; Szargel, Raymonde; Shani, Vered; Mekies, Lucy N.; Rott, Ruth; Lim, Grace G. Y.; Lim, Kah-Leong; Bandopadhyay, Rina; Wolosker, Herman; Engelender, Simone

    2013-01-01

    Parkin E3 ubiquitin-ligase activity and its role in mitochondria homeostasis are thought to play a role in Parkinson's disease (PD). We now report that AF-6 is a novel parkin interacting protein that modulates parkin ubiquitin-ligase activity and mitochondrial roles. Parkin interacts with the AF-6 PDZ region through its C-terminus. This leads to ubiquitination of cytosolic AF-6 and its degradation by the proteasome. On the other hand, endogenous AF-6 robustly increases parkin translocation and ubiquitin-ligase activity at the mitochondria. Mitochondrial AF-6 is not a parkin substrate, but rather co-localizes with parkin and enhances mitochondria degradation through PINK1/parkin-mediated mitophagy. On the other hand, several parkin and PINK1 juvenile disease-mutants are insensitive to AF-6 effects. AF-6 is present in Lewy bodies and its soluble levels are strikingly decreased in the caudate/putamen and substantia nigra of sporadic PD patients, suggesting that decreased AF-6 levels may contribute to the accumulation of dysfunctional mitochondria in the disease. The identification of AF-6 as a positive modulator of parkin translocation to the mitochondria sheds light on the mechanisms involved in PD and underscores AF-6 as a novel target for future therapeutics. PMID:23393160

  6. [Neurally adjusted ventilatory assist (NAVA). A new mode of assisted mechanical ventilation].

    PubMed

    Moerer, O; Barwing, J; Quintel, M

    2008-10-01

    The aim of mechanical ventilation is to assure gas exchange while efficiently unloading the respiratory muscles and mechanical ventilation is an integral part of the care of patients with acute respiratory failure. Modern lung protective strategies of mechanical ventilation include low-tidal-volume ventilation and the continuation of spontaneous breathing which has been shown to be beneficial in reducing atelectasis and improving oxygenation. Poor patient-ventilator interaction is a major issue during conventional assisted ventilation. Neurally adjusted ventilator assist (NAVA) is a new mode of mechanical ventilation that uses the electrical activity of the diaphragm (EAdi) to control the ventilator. First experimental studies showed an improved patient-ventilator synchrony and an efficient unloading of the respiratory muscles. Future clinical studies will have to show that NAVA is of clinical advantage when compared to conventional modes of assisted mechanical ventilation. This review characterizes NAVA according to current publications on this topic.

  7. Association Between Noninvasive Ventilation and Mortality Among Older Patients With Pneumonia

    PubMed Central

    Valley, Thomas S.; Walkey, Allan J.; Lindenauer, Peter K.; Wiener, Renda Soylemez; Cooke, Colin R.

    2016-01-01

    Objective Despite increasing use, evidence is mixed as to the appropriate use of noninvasive ventilation in patients with pneumonia. We aimed to determine the relationship between receipt of noninvasive ventilation and outcomes for patients with pneumonia in a real-world setting. Design, Setting, Patients We performed a retrospective cohort study of Medicare beneficiaries (aged > 64 yr) admitted to 2,757 acute-care hospitals in the United States with pneumonia, who received mechanical ventilation from 2010 to 2011. Exposures Noninvasive ventilation versus invasive mechanical ventilation. Measurement and Main Results The primary outcome was 30-day mortality with Medicare reimbursement as a secondary outcome. To account for unmeasured confounding associated with noninvasive ventilation use, an instrumental variable was used—the differential distance to a high noninvasive ventilation use hospital. All models were adjusted for patient and hospital characteristics to account for measured differences between groups. Among 65,747 Medicare beneficiaries with pneumonia who required mechanical ventilation, 12,480 (19%) received noninvasive ventilation. Patients receiving noninvasive ventilation were more likely to be older, male, white, rural-dwelling, have fewer comorbidities, and were less likely to be acutely ill as measured by organ failures. Results of the instrumental variable analysis suggested that, among marginal patients, receipt of noninvasive ventilation was not significantly associated with differences in 30-day mortality when compared with invasive mechanical ventilation (54% vs 55%; p = 0.92; 95% CI of absolute difference, –13.8 to 12.4) but was associated with significantly lower Medicare spending ($18,433 vs $27,051; p = 0.02). Conclusions Among Medicare beneficiaries hospitalized with pneumonia who received mechanical ventilation, noninvasive ventilation use was not associated with a real-world mortality benefit. Given the wide CIs, however, substantial

  8. Evaluation of the atoxigenic Aspergillus flavus strain AF36 in pistachio orchards

    USDA-ARS?s Scientific Manuscript database

    The atoxigenic strain Aspergillus flavus AF36, which has been extensively used as a biocontrol agent in commercial corn and cotton fields to reduce aflatoxin contamination, was applied in research pistachio orchards from 2002 to 2005 and in commercial pistachio orchards from 2008 to 2011. AF36 was a...

  9. The influence of music during mechanical ventilation and weaning from mechanical ventilation: A review

    PubMed Central

    Hetland, Breanna; Lindquist, Ruth; Chlan, Linda L.

    2015-01-01

    Background Mechanical ventilation (MV) causes many distressing symptoms. Weaning, the gradual decrease in ventilator assistance leading to termination of MV, increases respiratory effort, which may exacerbate symptoms and prolong MV. Music, a non-pharmacological intervention without side effects may benefit patients during weaning from mechanical ventilatory support. Methods A narrative review of OVID Medline, PsychINFO, and CINAHL databases was conducted to examine the evidence for the use of music intervention in MV and MV weaning. Results Music intervention had a positive impact on ventilated patients; 16 quantitative and 2 qualitative studies were identified. Quantitative studies included randomized clinical trials (10), case controls (3), pilot studies (2) and a feasibility study. Conclusions Evidence supports music as an effective intervention that can lesson symptoms related to MV and promote effective weaning. It has potential to reduce costs and increase patient satisfaction. However, more studies are needed to establish its use during MV weaning. PMID:26227333

  10. ASHRAE and residential ventilation

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

    Sherman, Max H.

    In the last quarter of a century, the western world has become increasingly aware of environmental threats to health and safety. During this period, people psychologically retreated away from outdoors hazards such as pesticides, smog, lead, oil spills, and dioxin to the seeming security of their homes. However, the indoor environment may not be healthier than the outdoor environment, as has become more apparent over the past few years with issues such as mold, formaldehyde, and sick-building syndrome. While the built human environment has changed substantially over the past 10,000 years, human biology has not; poor indoor air quality createsmore » health risks and can be uncomfortable. The human race has found, over time, that it is essential to manage the indoor environments of their homes. ASHRAE has long been in the business of ventilation, but most of the focus of that effort has been in the area of commercial and institutional buildings. Residential ventilation was traditionally not a major concern because it was felt that, between operable windows and envelope leakage, people were getting enough outside air in their homes. In the quarter of a century since the first oil shock, houses have gotten much more energy efficient. At the same time, the kinds of materials and functions in houses changed in character in response to people's needs. People became more environmentally conscious and aware not only about the resources they were consuming but about the environment in which they lived. All of these factors contributed to an increasing level of public concern about residential indoor air quality and ventilation. Where once there was an easy feeling about the residential indoor environment, there is now a desire to define levels of acceptability and performance. Many institutions--both public and private--have interests in Indoor Air Quality (IAQ), but ASHRAE, as the professional society that has had ventilation as part of its mission for over 100 years, is

  11. 46 CFR 194.10-25 - Ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... and shall serve no other space. Weather cowls shall be provided with a double layer of wire screen of... temperature below 100 °F. with 88 °F. weather air. Mechanical cooling may be used where ventilation... 130 °F. with an assumed outside temperature of 115 °F. (2) Ventilation supply weather openings shall...

  12. 46 CFR 194.10-25 - Ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... and shall serve no other space. Weather cowls shall be provided with a double layer of wire screen of... temperature below 100 °F. with 88 °F. weather air. Mechanical cooling may be used where ventilation... 130 °F. with an assumed outside temperature of 115 °F. (2) Ventilation supply weather openings shall...

  13. 46 CFR 194.10-25 - Ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... and shall serve no other space. Weather cowls shall be provided with a double layer of wire screen of... temperature below 100 °F. with 88 °F. weather air. Mechanical cooling may be used where ventilation... 130 °F. with an assumed outside temperature of 115 °F. (2) Ventilation supply weather openings shall...

  14. 46 CFR 194.10-25 - Ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... and shall serve no other space. Weather cowls shall be provided with a double layer of wire screen of... temperature below 100 °F. with 88 °F. weather air. Mechanical cooling may be used where ventilation... 130 °F. with an assumed outside temperature of 115 °F. (2) Ventilation supply weather openings shall...

  15. Noise measurements during high-frequency oscillatory and conventional mechanical ventilation.

    PubMed

    Berens, R J; Weigle, C G

    1995-10-01

    To evaluate the noise levels with high-frequency oscillatory ventilation and conventional mechanical ventilation. An observational, prospective study. Pediatric intensive care unit. The caretakers and environment of the pediatric intensive care unit. High-frequency oscillatory and conventional mechanical ventilation. Caretakers evaluated noise using a visual analog scale. Noise was measured with a decibel meter and an octave band frequency filter. There was twice as much noise perceived by the caretakers and as measured on the decibel A scale. All measures showed significantly greater noise, especially at low frequencies, with high-frequency oscillatory ventilation. High-frequency oscillatory ventilation exposes the patient to twice as much noise as does the use of conventional mechanical ventilation.

  16. Mobile communication devices causing interference in invasive and noninvasive ventilators.

    PubMed

    Dang, Bao P; Nel, Pierre R; Gjevre, John A

    2007-06-01

    The aim of this study was to assess if common mobile communication systems would cause significant interference on mechanical ventilation devices and at what distances would such interference occur. We tested all the invasive and noninvasive ventilatory devices used within our region. This consisted of 2 adult mechanical ventilators, 1 portable ventilator, 2 pediatric ventilators, and 2 noninvasive positive pressure ventilatory devices. We operated the mobile devices from the 2 cellular communication systems (digital) and 1 2-way radio system used in our province at varying distances from the ventilators and looked at any interference they created. We tested the 2-way radio system, which had a fixed operation power output of 3.0 watts, the Global Systems for Mobile Communication cellular system, which had a maximum power output of 2.0 watts and the Time Division Multiple Access cellular system, which had a maximum power output of 0.2 watts on our ventilators. The ventilators were ventilating a plastic lung at fixed settings. The mobile communication devices were tested at varying distances starting at zero meter from the ventilator and in all operation modes. The 2-way radio caused the most interference on some of the ventilators, but the maximum distance of interference was 1.0 m. The Global Systems for Mobile Communication system caused significant interference only at 0 m and minor interference at 0.5 m on only 1 ventilator. The Time Division Multiple Access system caused no interference at all. Significant interference consisted of a dramatic rise and fluctuation of the respiratory rate, pressure, and positive end-expiratory pressure of the ventilators with no normalization when the mobile device was removed. From our experiment on our ventilators with the communication systems used in our province, we conclude that mobile communication devices such as cellular phones and 2-way radios are safe and cause no interference unless operated at very close distances of

  17. WASTE HANDLING BUILDING VENTILATION SYSTEM DESCRIPTION DOCUMENT

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

    P.A. Kumar

    2000-06-21

    The Waste Handling Building Ventilation System provides heating, ventilation, and air conditioning (HVAC) for the contaminated, potentially contaminated, and uncontaminated areas of the Monitored Geologic Repository's (MGR) Waste Handling Building (WHB). In the uncontaminated areas, the non-confinement area ventilation system maintains the proper environmental conditions for equipment operation and personnel comfort. In the contaminated and potentially contaminated areas, in addition to maintaining the proper environmental conditions for equipment operation and personnel comfort, the contamination confinement area ventilation system directs potentially contaminated air away from personnel in the WHB and confines the contamination within high-efficiency particulate air (HEPA) filtration units. Themore » contamination confinement areas ventilation system creates airflow paths and pressure zones to minimize the potential for spreading contamination within the building. The contamination confinement ventilation system also protects the environment and the public by limiting airborne releases of radioactive or other hazardous contaminants from the WHB. The Waste Handling Building Ventilation System is designed to perform its safety functions under accident conditions and other Design Basis Events (DBEs) (such as earthquakes, tornadoes, fires, and loss of the primary electric power). Additional system design features (such as compartmentalization with independent subsystems) limit the potential for cross-contamination within the WHB. The system provides status of important system parameters and equipment operation, and provides audible and/or visual indication of off-normal conditions and equipment failures. The Waste Handling Building Ventilation System confines the radioactive and hazardous material within the building such that the release rates comply with regulatory limits. The system design, operations, and maintenance activities incorporate ALARA (as low as is

  18. Stroke of Known Cause and Underlying Atrial Fibrillation (STROKE-AF) randomized trial: Design and rationale.

    PubMed

    Bernstein, Richard A; Kamel, Hooman; Granger, Christopher B; Kowal, Robert C; Ziegler, Paul D; Schwamm, Lee H

    2017-08-01

    Approximately 20% of ischemic strokes are associated with clinically apparent atrial fibrillation (AF). Regardless of stroke etiology, detection of AF in patients with ischemic strokes often changes antithrombotic treatment from anti-platelet to oral anticoagulation therapy. The role and the optimum duration of cardiac monitoring to detect AF in patients with strokes presumed due to large vessel atherosclerosis or small vessel disease is unknown. This manuscript describes the design and rationale of the STROKE-AF trial. STROKE-AF is a randomized, controlled, open-label, post-market clinical trial. Detection of AF will be evaluated using continuous arrhythmia monitoring with an insertable cardiac monitor (ICM) compared with standard of care follow-up in patients with stroke (within the prior 10 days) that is presumed due to large vessel cervical or intracranial atherosclerosis, or to small vessel disease. Approximately 500 patients will be enrolled at approximately 40 centers in the United States. Patients will be randomized 1:1 to arrhythmia monitoring with an ICM (continuous monitoring arm) or standard of care follow-up (control arm). Subjects will be followed for ≥12 months and up to 3 years. The primary objective is to compare the incidence rate of detected AF through 12 months of follow-up between the two arms. This trial will provide information on the value of ICMs to detect subclinical AF in patients with stroke presumed due to large vessel atherosclerosis or small vessel disease, which will have implications for guiding treatment with oral anticoagulation for secondary stroke prevention. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Economic, Environmental and Health Implications of Enhanced Ventilation in Office Buildings.

    PubMed

    MacNaughton, Piers; Pegues, James; Satish, Usha; Santanam, Suresh; Spengler, John; Allen, Joseph

    2015-11-18

    Current building ventilation standards are based on acceptable minimums. Three decades of research demonstrates the human health benefits of increased ventilation above these minimums. Recent research also shows the benefits on human decision-making performance in office workers, which translates to increased productivity. However, adoption of enhanced ventilation strategies is lagging. We sought to evaluate two of the perceived potential barriers to more widespread adoption-Economic and environmental costs. We estimated the energy consumption and associated per building occupant costs for office buildings in seven U.S. cities, representing different climate zones for three ventilation scenarios (standard practice (20 cfm/person), 30% enhanced ventilation, and 40 cfm/person) and four different heating, ventilation and air conditioning (HVAC) system strategies (Variable Air Volume (VAV) with reheat and a Fan Coil Unit (FCU), both with and without an energy recovery ventilator). We also estimated emissions of greenhouse gases associated with this increased energy usage, and, for comparison, converted this to the equivalent number of vehicles using greenhouse gas equivalencies. Lastly, we paired results from our previous research on cognitive function and ventilation with labor statistics to estimate the economic benefit of increased productivity associated with increasing ventilation rates. Doubling the ventilation rate from the American Society of Heating, Refrigeration and Air-Conditioning Engineers minimum cost less than $40 per person per year in all climate zones investigated. Using an energy recovery ventilation system significantly reduced energy costs, and in some scenarios led to a net savings. At the highest ventilation rate, adding an ERV essentially neutralized the environmental impact of enhanced ventilation (0.03 additional cars on the road per building across all cities). The same change in ventilation improved the performance of workers by 8

  20. Economic, Environmental and Health Implications of Enhanced Ventilation in Office Buildings

    PubMed Central

    MacNaughton, Piers; Pegues, James; Satish, Usha; Santanam, Suresh; Spengler, John; Allen, Joseph

    2015-01-01

    Introduction: Current building ventilation standards are based on acceptable minimums. Three decades of research demonstrates the human health benefits of increased ventilation above these minimums. Recent research also shows the benefits on human decision-making performance in office workers, which translates to increased productivity. However, adoption of enhanced ventilation strategies is lagging. We sought to evaluate two of the perceived potential barriers to more widespread adoption—Economic and environmental costs. Methods: We estimated the energy consumption and associated per building occupant costs for office buildings in seven U.S. cities, representing different climate zones for three ventilation scenarios (standard practice (20 cfm/person), 30% enhanced ventilation, and 40 cfm/person) and four different heating, ventilation and air conditioning (HVAC) system strategies (Variable Air Volume (VAV) with reheat and a Fan Coil Unit (FCU), both with and without an energy recovery ventilator). We also estimated emissions of greenhouse gases associated with this increased energy usage, and, for comparison, converted this to the equivalent number of vehicles using greenhouse gas equivalencies. Lastly, we paired results from our previous research on cognitive function and ventilation with labor statistics to estimate the economic benefit of increased productivity associated with increasing ventilation rates. Results: Doubling the ventilation rate from the American Society of Heating, Refrigeration and Air-Conditioning Engineers minimum cost less than $40 per person per year in all climate zones investigated. Using an energy recovery ventilation system significantly reduced energy costs, and in some scenarios led to a net savings. At the highest ventilation rate, adding an ERV essentially neutralized the environmental impact of enhanced ventilation (0.03 additional cars on the road per building across all cities). The same change in ventilation improved the

  1. Comfort parameters - Ventilation of a subway wagon

    NASA Astrophysics Data System (ADS)

    Petr, Pavlíček; Ladislav, Tříska

    2017-09-01

    Research and development of a ventilation system is being carried out as a part of project TA04030774 of the Technology Agency of the Czech Republic. Name of the project is "Research and Development of Mass-optimized Components for Rail Vehicles". Problems being solved are development and testing of a new concept for ventilation systems for public transport vehicles. The main improvements should be a reduction of the mass of the whole system, easy installation and reduction of the noise of the ventilation system. This article is focused on the comfort parameters in a subway wagon (measurement and evaluation carried out on a function sample in accordance with the regulations). The input to the project is a ventilator hybrid casing for a subway wagon, which was manufactured and tested during the Ministry of Industry and Trade project TIP FR-TI3/449.

  2. 46 CFR 185.352 - Ventilation of gasoline machinery spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Ventilation of gasoline machinery spaces. 185.352... (UNDER 100 GROSS TONS) OPERATIONS Miscellaneous Operating Requirements § 185.352 Ventilation of gasoline machinery spaces. The mechanical exhaust for the ventilation of a gasoline machinery space, required by...

  3. 46 CFR 185.352 - Ventilation of gasoline machinery spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Ventilation of gasoline machinery spaces. 185.352... (UNDER 100 GROSS TONS) OPERATIONS Miscellaneous Operating Requirements § 185.352 Ventilation of gasoline machinery spaces. The mechanical exhaust for the ventilation of a gasoline machinery space, required by...

  4. 46 CFR 185.352 - Ventilation of gasoline machinery spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Ventilation of gasoline machinery spaces. 185.352... (UNDER 100 GROSS TONS) OPERATIONS Miscellaneous Operating Requirements § 185.352 Ventilation of gasoline machinery spaces. The mechanical exhaust for the ventilation of a gasoline machinery space, required by...

  5. 24 CFR 3285.505 - Crawlspace ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... of ventilation openings must not be less than one square foot (ft.2) for every 150 square feet (ft.2) of the home's floor area. The total area of ventilation openings may be reduced to one square foot (ft.2) for every 1,500 square feet (ft.2) of the home's floor area, where a uniform 6-mil polyethylene...

  6. 24 CFR 3285.505 - Crawlspace ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... of ventilation openings must not be less than one square foot (ft.2) for every 150 square feet (ft.2) of the home's floor area. The total area of ventilation openings may be reduced to one square foot (ft.2) for every 1,500 square feet (ft.2) of the home's floor area, where a uniform 6-mil polyethylene...

  7. 24 CFR 3285.505 - Crawlspace ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... of ventilation openings must not be less than one square foot (ft.2) for every 150 square feet (ft.2) of the home's floor area. The total area of ventilation openings may be reduced to one square foot (ft.2) for every 1,500 square feet (ft.2) of the home's floor area, where a uniform 6-mil polyethylene...

  8. 24 CFR 3285.505 - Crawlspace ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... of ventilation openings must not be less than one square foot (ft.2) for every 150 square feet (ft.2) of the home's floor area. The total area of ventilation openings may be reduced to one square foot (ft.2) for every 1,500 square feet (ft.2) of the home's floor area, where a uniform 6-mil polyethylene...

  9. Damage to cochlear efferents following AF64A intoxication.

    PubMed

    Smith, D W; Mount, R J

    1993-07-01

    Damage to cochlear efferents in chinchillas was assessed using transmission electron microscopy following unilateral treatment with the cholinotoxin ethylcholine mustard aziridinium ion (AF64A). AF64A was diluted in artificial perilymph to concentrations ranging from 0.5 to 100 microM. Survival times ranged from 1 to 12 weeks. At concentrations above 10 microM, widespread damage was noted to efferent fibers within the inner spiral bundle (ISB), tunnel spiral bundle (TSB), tunnel radial fibers (TRF) and efferent terminals at the base of OHCs. This damage included degeneration of fibers and terminals, delamination of mitochondria, vacuolization, and loss of cell membrane. However, at high concentrations, non-specific damage was also noted as thinnings or discontinuities of the membrane of OHCs and afferent fibers. At concentrations between 3 and 10 microM, selective damage was observed to efferent fibers within the ISB, TSB, TRF, and to terminals at the base of the OHCs, with all other structures appearing normal. At concentrations of 0.5 and 1 microM, damage was limited to efferent fibers within the TSB and ISB below the inner hair cells. In general, insult was greatest to middle- and basal-turn efferents, and longer survival times did not produce greater damage to, or loss of, efferents. These data suggest that at low concentrations, AF64A produces a partial yet selective degeneration of cochlear efferents within both the medial and lateral tracts, and that at the lowest concentrations used in these studies, AF64A produces a preferential insult on lateral olivocochlear efferents.

  10. Protective ventilation in experimental acute respiratory distress syndrome after ventilator-induced lung injury: a randomized controlled trial.

    PubMed

    Uttman, L; Bitzén, U; De Robertis, E; Enoksson, J; Johansson, L; Jonson, B

    2012-10-01

    Low tidal volume (V(T)), PEEP, and low plateau pressure (P(PLAT)) are lung protective during acute respiratory distress syndrome (ARDS). This study tested the hypothesis that the aspiration of dead space (ASPIDS) together with computer simulation can help maintain gas exchange at these settings, thus promoting protection of the lungs. ARDS was induced in pigs using surfactant perturbation plus an injurious ventilation strategy. One group then underwent 24 h protective ventilation, while control groups were ventilated using a conventional ventilation strategy at either high or low pressure. Pressure-volume curves (P(el)/V), blood gases, and haemodynamics were studied at 0, 4, 8, 16, and 24 h after the induction of ARDS and lung histology was evaluated. The P(el)/V curves showed improvements in the protective strategy group and deterioration in both control groups. In the protective group, when respiratory rate (RR) was ≈ 60 bpm, better oxygenation and reduced shunt were found. Histological damage was significantly more severe in the high-pressure group. There were no differences in venous oxygen saturation and pulmonary vascular resistance between the groups. The protective ventilation strategy of adequate pH or PaCO2 with minimal V(T), and high/safe P(PLAT) resulting in high PEEP was based on the avoidance of known lung-damaging phenomena. The approach is based upon the optimization of V(T), RR, PEEP, I/E, and dead space. This study does not lend itself to conclusions about the independent role of each of these features. However, dead space reduction is fundamental for achieving minimal V(T) at high RR. Classical physiology is applicable at high RR. Computer simulation optimizes ventilation and limiting of dead space using ASPIDS. Inspiratory P(el)/V curves recorded from PEEP or, even better, expiratory P(el)/V curves allow monitoring in ARDS.

  11. Improved oxygenation 24 hours after transition to airway pressure release ventilation or high-frequency oscillatory ventilation accurately discriminates survival in immunocompromised pediatric patients with acute respiratory distress syndrome*.

    PubMed

    Yehya, Nadir; Topjian, Alexis A; Thomas, Neal J; Friess, Stuart H

    2014-05-01

    Children with an immunocompromised condition and requiring invasive mechanical ventilation have high risk of death. Such patients are commonly transitioned to rescue modes of nonconventional ventilation, including airway pressure release ventilation and high-frequency oscillatory ventilation, for acute respiratory distress syndrome refractory to conventional ventilation. Our aim was to describe our experience with airway pressure release ventilation and high-frequency oscillatory ventilation in children with an immunocompromised condition and acute respiratory distress syndrome refractory to conventional ventilation and to identify factors associated with survival. Retrospective cohort study. Tertiary care, university-affiliated PICU. Sixty pediatric patients with an immunocompromised condition and acute respiratory distress syndrome refractory to conventional ventilation transitioned to either airway pressure release ventilation or high-frequency oscillatory ventilation. None. Demographic data, ventilator settings, arterial blood gases, oxygenation index, and PaO(2)/FIO(2) were recorded before transition to either mode of nonconventional ventilation and at predetermined intervals after transition for up to 5 days. Mortality in the entire cohort was 63% and did not differ between patients transitioned to airway pressure release ventilation and high-frequency oscillatory ventilation. For both airway pressure release ventilation and high-frequency oscillatory ventilation, improvements in oxygenation index and PaO(2)/FIO(2) at 24 hours expressed as a fraction of pretransition values (oxygenation index(24)/oxygenation index(pre) and PaO(2)/FIO(224)/PaO(2)/FIO(2pre)) reliably discriminated nonsurvivors from survivors, with receiver operating characteristic areas under the curves between 0.89 and 0.95 (p for all curves < 0.001). Sensitivity-specificity analysis suggested that less than 15% reduction in oxygenation index (90% sensitive, 75% specific) or less than 90

  12. Ethical challenges in home mechanical ventilation: a secondary analysis.

    PubMed

    Dybwik, Knut; Nielsen, Erik Waage; Brinchmann, Berit Støre

    2012-03-01

    The aim of this study was to explore the ethical challenges in home mechanical ventilation based on a secondary analysis of qualitative empirical data. The data included perceptions of healthcare professionals in hospitals and community health services and family members of children and adults using home mechanical ventilation. The findings show that a number of ethical challenges, or dilemmas, arise at all levels in the course of treatment: deciding who should be offered home mechanical ventilation, respect for patient and family wishes, quality of life, dignity and equal access to home mechanical ventilation. Other challenges were the impacts home mechanical ventilation had on the patient, the family, the healthcare services and the allocation of resources. A better and broader understanding of these issues is crucial in order to improve the quality of care for both patient and family and assist healthcare professionals involved in home mechanical ventilation to make decisions for the good of the patient and his or her family.

  13. Prone versus supine position in mechanically ventilated children: a pilot study.

    PubMed

    Sawhney, Ashu; Kumar, Nirmal; Sreenivas, Vishnubhatla; Gupta, Sangeeta; Tyagi, Vineet; Puliyel, Jacob M

    2005-05-01

    It is known that mechanically ventilated patients in the prone position have improved oxygenation compared with those supine. We did a prospective, randomized, controlled trial to evaluate the effect of prone position during mechanical ventilation, on survival in critically ill children. Forty-two children needing mechanical ventilation for various illnesses were randomized to receive initial ventilation for four hours prone or supine by drawing lots. Initial severity of illness and blood gases in all children were noted. In a crossover design, after the initial four hours the children were turned over and ventilated in the alternate posture for an hour. Oxygenation parameters and mean airway pressures were noted at one hour, four hours, and five hours. Mortality, duration of ventilation, and the above parameters were compared in the two groups. Initial PRISM scores were similar in the two groups. Mortality in the prone group was less than in the supine group. The odds ratio of mortality was 0.20 (95% CI 0.05-0.75). Duration of ventilation was similar in the two groups. The oxygenation index was significantly lower in the prone group at one, four, and five hours after onset of ventilation. Prone position in the first few hours of ventilation significantly improves gas exchange and oxygenation, reduces the mean airway pressures required to ventilate children, and may cause significant improvement in survival. Our study protocol allowed ventilator settings to be changed as needed during ventilation.

  14. The splicing factor U2AF65 stabilizes TRF1 protein by inhibiting its ubiquitin-dependent proteolysis

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

    Kim, Jeonghee; Chung, In Kwon, E-mail: topoviro@yonsei.ac.kr

    Highlights: •Identification of U2AF65 as a novel TRF1-interacting protein. •U2AF65 stabilizes TRF1 protein by inhibiting its ubiquitin-dependent proteolysis. •U2AF65 interferes with the interaction between TRF1 and Fbx4. •U2AF65 represents a new route for modulating TRF1 function at telomeres. -- Abstract: The human telomeric protein TRF1 is a component of the six-subunit protein complex shelterin, which provides telomere protection by organizing the telomere into a high-order structure. TRF1 functions as a negative regulator of telomere length by controlling the access of telomerase to telomeres. Thus, the cellular abundance of TRF1 at telomeres should be maintained and tightly regulated to ensure propermore » telomere function. Here, we identify U2 small nuclear ribonucleoprotein (snRNP) auxiliary factor 65 (U2AF65), an essential pre-mRNA splicing factor, as a novel TRF1-interacting protein. U2AF65 interacts with TRF1 in vitro and in vivo and is capable of stabilizing TRF1 protein by inhibiting its ubiquitin-dependent proteolysis. We also found that U2AF65 interferes with the interaction between TRF1 and Fbx4, an E3 ubiquitin ligase for TRF1. Depletion of endogenous U2AF65 expression by short interfering RNA (siRNA) reduced the stability of endogenous TRF1 whereas overexpression of U2AF65 significantly extended the half-life of TRF1. These findings demonstrate that U2AF65 plays a critical role in regulating the level of TRF1 through physical interaction and ubiquitin-mediated proteolysis. Hence, U2AF65 represents a new route for modulating TRF1 function at telomeres.« less

  15. Inspired gas humidity and temperature during mechanical ventilation with the Stephanie ventilator.

    PubMed

    Preo, Bianca L; Shadbolt, Bruce; Todd, David A

    2013-11-01

    To measure inspired gas humidity and temperature delivered by a Stephanie neonatal ventilator with variations in (i) circuit length; (ii) circuit insulation; (iii) proximal airway temperature probe (pATP) position; (iv) inspiratory temperature (offset); and (v) incubator temperatures. Using the Stephanie neonatal ventilator, inspired gas humidity and temperature were measured during mechanical ventilation at the distal inspiratory limb and 3 cm down the endotracheal tube. Measurements were made with a long or short circuit; with or without insulation of the inspiratory limb; proximal ATP (pATP) either within or external to the incubator; at two different inspiratory temperature (offset) of 37(-0.5) and 39(-2.0)°C; and at three different incubator temperatures of 32, 34.5, and 37°C. Long circuits produced significantly higher inspired humidity than short circuits at all incubator settings, while only at 32°C was the inspired temperature higher. In the long circuits, insulation further improved the inspired humidity especially at 39(-2.0)°C, while only at incubator temperatures of 32 and 37°C did insulation significantly improve inspired temperature. Positioning the pATP outside the incubator did not result in higher inspired humidity but did significantly improve inspired temperature. An inspiratory temperature (offset) of 39(-2.0)°C delivered significantly higher inspired humidity and temperature than the 37(-0.5)°C especially when insulated. Long insulated Stephanie circuits should be used for neonatal ventilation when the infant is nursed in an incubator. The recommended inspiratory temperature (offset) of 37(-0.5)°C produced inspired humidity and temperature below international standards, and we suggest an increase to 39(-2.0)°C. © 2013 John Wiley & Sons Ltd.

  16. 46 CFR 190.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Ventilation for closed spaces. 190.15-10 Section 190.15... CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-10 Ventilation for closed spaces. (a) All enclosed spaces... chemical laboratories, scientific laboratories, chemical storerooms, and machinery spaces and for closing...

  17. 46 CFR 190.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Ventilation for closed spaces. 190.15-10 Section 190.15... CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-10 Ventilation for closed spaces. (a) All enclosed spaces... chemical laboratories, scientific laboratories, chemical storerooms, and machinery spaces and for closing...

  18. 46 CFR 190.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Ventilation for closed spaces. 190.15-10 Section 190.15... CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-10 Ventilation for closed spaces. (a) All enclosed spaces... chemical laboratories, scientific laboratories, chemical storerooms, and machinery spaces and for closing...

  19. 46 CFR 190.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Ventilation for closed spaces. 190.15-10 Section 190.15... CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-10 Ventilation for closed spaces. (a) All enclosed spaces... chemical laboratories, scientific laboratories, chemical storerooms, and machinery spaces and for closing...

  20. 46 CFR 190.15-10 - Ventilation for closed spaces.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Ventilation for closed spaces. 190.15-10 Section 190.15... CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-10 Ventilation for closed spaces. (a) All enclosed spaces... chemical laboratories, scientific laboratories, chemical storerooms, and machinery spaces and for closing...

  1. 46 CFR 111.106-15 - Ventilation of hazardous locations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... its operational controls outside the ventilated space, if the system is mechanical; and (3) Have a... opening. (c) The mechanical ventilation of enclosed flammable or combustible liquid cargo handling or.... The power ventilation system must be designed to remove vapors from the bottom of the space at points...

  2. Limiting ventilator-induced lung injury through individual electronic medical record surveillance.

    PubMed

    Herasevich, Vitaly; Tsapenko, Mykola; Kojicic, Marija; Ahmed, Adil; Kashyap, Rachul; Venkata, Chakradhar; Shahjehan, Khurram; Thakur, Sweta J; Pickering, Brian W; Zhang, Jiajie; Hubmayr, Rolf D; Gajic, Ognjen

    2011-01-01

    To improve the safety of ventilator care and decrease the risk of ventilator-induced lung injury, we designed and tested an electronic algorithm that incorporates patient characteristics and ventilator settings, allowing near-real-time notification of bedside providers about potentially injurious ventilator settings. Electronic medical records of consecutive patients who received invasive ventilation were screened in three Mayo Clinic Rochester intensive care units. The computer system alerted bedside providers via the text paging notification about potentially injurious ventilator settings. Alert criteria included a Pao2/Fio2 ratio of <300 mm Hg, free text search for the words "edema" or "bilateral + infiltrates" on the chest radiograph report, a tidal volume of >8 mL/kg predicted body weight (based on patient gender and height), a plateau pressure of >30 cm H2O, and a peak airway pressure of >35 cm H2O. Respiratory therapists answered a brief online satisfaction survey. Ventilator-induced lung injury risk was compared before and after the introduction of ventilator-induced lung injury alert. The prevalence of acute lung injury was 42% (n = 490) among 1,159 patients receiving >24 hrs of invasive ventilation. The system sent 111 alerts for 80 patients, with a positive predictive value of 59%. The exposure to potentially injurious ventilation decreased after the intervention from 40.6 ± 74.6 hrs to 26.9 ± 77.3 hrs (p = .004). Electronic medical record surveillance of mechanically ventilated patients accurately detects potentially injurious ventilator settings and is able to influence bedside practice at moderate costs. Its implementation is associated with decreased patient exposure to potentially injurious mechanical ventilation settings.

  3. Moderately high frequency ventilation with a conventional ventilator allows reduction of tidal volume without increasing mean airway pressure.

    PubMed

    Cordioli, Ricardo Luiz; Park, Marcelo; Costa, Eduardo Leite Vieira; Gomes, Susimeire; Brochard, Laurent; Amato, Marcelo Britto Passos; Azevedo, Luciano Cesar Pontes

    2014-12-01

    The aim of this study was to explore if positive-pressure ventilation delivered by a conventional ICU ventilator at a moderately high frequency (HFPPV) allows a safe reduction of tidal volume (V T) below 6 mL/kg in a porcine model of severe acute respiratory distress syndrome (ARDS) and at a lower mean airway pressure than high-frequency oscillatory ventilation (HFOV). This is a prospective study. In eight pigs (median weight 34 [29,36] kg), ARDS was induced by pulmonary lavage and injurious ventilation. The animals were ventilated with a randomized sequence of respiratory rates: 30, 60, 90, 120, 150, followed by HFOV at 5 Hz. At each step, V T was adjusted to allow partial pressure of arterial carbon dioxide (PaCO2) to stabilize between 57 and 63 mmHg. Data are shown as median [P25th,P75th]. After lung injury, the PaO2/FiO2 (P/F) ratio was 92 [63,118] mmHg, pulmonary shunt 26 [17,31]%, and static compliance 11 [8,14] mL/cmH2O. Positive end-expiratory pressure (PEEP) was 14 [10,17] cmH2O. At 30 breaths/min, V T was higher than 6 (7.5 [6.8,10.2]) mL/kg, but at all higher frequencies, V T could be reduced and PaCO2 maintained, leading to reductions in plateau pressures and driving pressures. For frequencies of 60 to 150/min, V T progressively fell from 5.2 [5.1,5.9] to 3.8 [3.7,4.2] mL/kg (p < 0.001). There were no detrimental effects in terms of lung mechanics, auto-PEEP generation, hemodynamics, or gas exchange. Mean airway pressure was maintained constant and was increased only during HFOV. During protective mechanical ventilation, HFPPV delivered by a conventional ventilator in a severe ARDS swine model safely allows further tidal volume reductions. This strategy also allowed decreasing airway pressures while maintaining stable PaCO2 levels.

  4. Neglecting Democracy in Education Policy: A-F School Report Card Accountability Systems

    ERIC Educational Resources Information Center

    Murray, Kevin; Howe, Kenneth R.

    2017-01-01

    Sixteen states have adopted school report card accountability systems that assign A-F letter grades to schools. Other states are now engaged in deliberation about whether they, too, should adopt such systems. This paper examines A-F accountability systems with respect to three kinds of validity. First, it examines whether or not these…

  5. Continuous distributions of specific ventilation recovered from inert gas washout

    NASA Technical Reports Server (NTRS)

    Lewis, S. M.; Evans, J. W.; Jalowayski, A. A.

    1978-01-01

    A new technique is described for recovering continuous distributions of ventilation as a function of tidal ventilation/volume ratio from the nitrogen washout. The analysis yields a continuous distribution of ventilation as a function of tidal ventilation/volume ratio represented as fractional ventilations of 50 compartments plus dead space. The procedure was verified by recovering known distributions from data to which noise had been added. Using an apparatus to control the subject's tidal volume and FRC, mixed expired N2 data gave the following results: (a) the distributions of young, normal subjects were narrow and unimodal; (b) those of subjects over age 40 were broader with more poorly ventilated units; (c) patients with pulmonary disease of all descriptions showed enlarged dead space; (d) patients with cystic fibrosis showed multimodal distributions with the bulk of the ventilation going to overventilated units; and (e) patients with obstructive lung disease fell into several classes, three of which are illustrated.

  6. [Bellows or bag? Testing 10 ventilators and some medical history comments].

    PubMed

    Kötter, K P; Maleck, W H; Altmannsberger, S; Herchet, J; Petroianu, G A

    1998-01-01

    We compared a new bellows ventilator (Kendall Cardiovent) with two other bellows (Dräger Resutator 63, Tagg Breathsaver) and seven bag or ball ventilators (Aerodyne Hope, Ambu Mark 3, Ambu Silicon, Dräger Resutator 2000, Laerdal Resu, Mercury CPR, Weinmann Combibag). Tidal volumes were measured with two Laerdal Recording Resusci Annies, one lying on the floor, one in a bed. Twelve participants performed mask ventilation with all ten devices on both manikins for two minutes, trying to achieve tidal volumes of between 0.8 and 1.21 as recommended by the AHA. The last ten ventilations each on the graphic strips were analysed for volume. The participants scored handling of the devices on a 6-point scale (1 = very good, 6 = insufficient). The results of the Cardiovent were compared to those of the other devices by rank sum test (percentage of correct ventilations) and sign test (subjective handling). The Cardiovent provided exact ventilation with 95% of ventilations) on the floor and 78% of ventilations in bed in the recommended range. However, the percentage of correct ventilations with the Cardiovent was not significantly different to the other devices except for a lower percentage of correct ventilations with the Combibag in the in bed setting. Concerning subjective handling, the Cardiovent was significantly superior to several ball ventilators.

  7. 46 CFR 171.118 - Automatic ventilators and side ports.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Automatic ventilators and side ports. 171.118 Section... SPECIAL RULES PERTAINING TO VESSELS CARRYING PASSENGERS Openings in the Side of a Vessel Below the Bulkhead or Weather Deck § 171.118 Automatic ventilators and side ports. (a) An automatic ventilator must...

  8. 46 CFR 171.118 - Automatic ventilators and side ports.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Automatic ventilators and side ports. 171.118 Section... SPECIAL RULES PERTAINING TO VESSELS CARRYING PASSENGERS Openings in the Side of a Vessel Below the Bulkhead or Weather Deck § 171.118 Automatic ventilators and side ports. (a) An automatic ventilator must...

  9. 46 CFR 171.118 - Automatic ventilators and side ports.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Automatic ventilators and side ports. 171.118 Section... SPECIAL RULES PERTAINING TO VESSELS CARRYING PASSENGERS Openings in the Side of a Vessel Below the Bulkhead or Weather Deck § 171.118 Automatic ventilators and side ports. (a) An automatic ventilator must...

  10. 46 CFR 171.118 - Automatic ventilators and side ports.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Automatic ventilators and side ports. 171.118 Section... SPECIAL RULES PERTAINING TO VESSELS CARRYING PASSENGERS Openings in the Side of a Vessel Below the Bulkhead or Weather Deck § 171.118 Automatic ventilators and side ports. (a) An automatic ventilator must...

  11. 46 CFR 171.118 - Automatic ventilators and side ports.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Automatic ventilators and side ports. 171.118 Section... SPECIAL RULES PERTAINING TO VESSELS CARRYING PASSENGERS Openings in the Side of a Vessel Below the Bulkhead or Weather Deck § 171.118 Automatic ventilators and side ports. (a) An automatic ventilator must...

  12. Risk factors associated with development of ventilator associated pneumonia.

    PubMed

    Noor, Ahmed; Hussain, Syed Fayyaz

    2005-02-01

    To assess the risk factors associated with development of ventilator associated pneumonia (VAP). A case control study. Intensive Care Unit (ICU) at the Aga Khan University Hospital, Karachi, between January 1999 and June 2000. All patients with assisted mechanical ventilation were assessed for the development of VAP. Risk factors associated with development of VAP were determined. Adult patients who developed pneumonia, 48 hours after ventilation, were called cases while those who did not develop pneumonia were called controls. Seventy (28%) out of 250 mechanically ventilated patients developed VAP (rate of VAP was 26 cases per 1000 ventilator days). Shock during first 48 hours of ventilation (odds ratio (OR), 5.95; 95% confidence interval (CI), 2.83-12.52), transport out of ICU during mechanical ventilation (OR, 6.0; 95% CI, 2.92-12.37), re-intubation (OR, 4.23; 95% CI, 2.53-9.85), prior episode of aspiration of gastric content (OR, 3.07; 95% CI, 1.35-7.01), and use of antibiotics prior to intubation (OR,2.55; 95% CI, 1.20-5.41) were found to be independently associated with a higher risk of developing VAP. Gram negative organisms and Staphylococcus aureus were responsible for over 90% of cases. Patients with VAP had higher crude mortality rate (57.1%) compared with controls (32.2%). Ventilator associated pneumonia is associated with a high mortality. This study has identified risk factors associated with VAP.

  13. Protective mechanical ventilation in United Kingdom critical care units: A multicentre audit

    PubMed Central

    Martin, Matthew J; Richardson, Neil; Bourdeaux, Christopher P

    2016-01-01

    Lung protective ventilation is becoming increasingly used for all critically ill patients being mechanically ventilated on a mandatory ventilator mode. Compliance with the universal application of this ventilation strategy in intensive care units in the United Kingdom is unknown. This 24-h audit of ventilation practice took place in 16 intensive care units in two regions of the United Kingdom. The mean tidal volume for all patients being ventilated on a mandatory ventilator mode was 7.2(±1.4) ml kg−1 predicted body weight and overall compliance with low tidal volume ventilation (≤6.5 ml kg−1 predicted body weight) was 34%. The mean tidal volume for patients ventilated with volume-controlled ventilation was 7.0(±1.2) ml kg−1 predicted body weight and 7.9(±1.8) ml kg−1 predicted body weight for pressure-controlled ventilation (P < 0.0001). Overall compliance with recommended levels of positive end-expiratory pressure was 72%. Significant variation in practice existed both at a regional and individual unit level. PMID:28979556

  14. Protective mechanical ventilation in United Kingdom critical care units: A multicentre audit.

    PubMed

    Newell, Christopher P; Martin, Matthew J; Richardson, Neil; Bourdeaux, Christopher P

    2017-05-01

    Lung protective ventilation is becoming increasingly used for all critically ill patients being mechanically ventilated on a mandatory ventilator mode. Compliance with the universal application of this ventilation strategy in intensive care units in the United Kingdom is unknown. This 24-h audit of ventilation practice took place in 16 intensive care units in two regions of the United Kingdom. The mean tidal volume for all patients being ventilated on a mandatory ventilator mode was 7.2(±1.4) ml kg -1 predicted body weight and overall compliance with low tidal volume ventilation (≤6.5 ml kg -1 predicted body weight) was 34%. The mean tidal volume for patients ventilated with volume-controlled ventilation was 7.0(±1.2) ml kg -1 predicted body weight and 7.9(±1.8) ml kg -1 predicted body weight for pressure-controlled ventilation ( P  < 0.0001). Overall compliance with recommended levels of positive end-expiratory pressure was 72%. Significant variation in practice existed both at a regional and individual unit level.

  15. Home Ventilator Guide

    MedlinePlus

    ... SpO 2 , low minute ventilation,apnea, high leak, non-vent- ed mask, circuit occlusion/discon- nect, malfunction, ... failure, block tube, tube discon- nect, high leak, non- vented mask, low minute volume, apnea, low SpO ...

  16. [Establishment of the retrovirus-mediated murine model with MLL-AF9 leukemia].

    PubMed

    Xu, Si-Miao; Yang, Yang; Zhou, Mi; Zhao, Xue-Jiao; Qin, Yu; Zhang, Pei-Ling; Yuan, Rui-Feng; Zhou, Jian-Feng; Fang, Yong

    2013-10-01

    This study was purposed to establish a retrovirus-mediated murine model with MLL-AF9 leukemia, so as to provide a basis for further investigation of the pathogenesis and therapeutic strategy of MLL associated leukemia. Murine (CD45.2) primary hematopoietic precursor positively selected for expression of the progenitor marker c-Kit by means of MACS were transduced with a retrovirus carrying MLL-AF9 fusion gene. After cultured in vitro, the transduced cells were injected intravenously through the tail vein into the lethally irradiated mice (CD45.1). PCR, flow cytometry and morphological observation were employed to evaluate the murine leukemia model system. The results showed that MLL-AF9 fusion gene was expressed in the infected cells, and the cells had a dramatically enhanced potential to generate myeloid colonies with primitive and immature morphology. Flow cytometric analysis revealed that the immortalized cells highly expressed myeloid lineage surface markers Gr-1 and Mac-1. Moreover, the expression levels of Hoxa9 and Meis1 mRNA were significantly higher in the MLL-AF9 cells than that in control. The mice transplanted with MLL-AF9 cells displayed typical signs of leukemia within 6-12 weeks. Extensive infiltration leukemic cells was observed in the Wright-Giemsa stained peripheral blood smear and bone marrow, and also in the histology of liver and spleen. Flow cytometric analysis of the bone marrow and spleen cells demonstrated that the CD45.2 populations expressed highly myeloid markers Gr-1 and Mac-1. The leukemic mice died within 12 weeks. It is concluded that the retrovirus-mediated murine model with MLL-AF9 leukemia is successfully established, which can be applied in the subsequent researches.

  17. A description of intraoperative ventilator management in patients with acute lung injury and the use of lung protective ventilation strategies.

    PubMed

    Blum, James M; Maile, Michael; Park, Pauline K; Morris, Michelle; Jewell, Elizabeth; Dechert, Ronald; Rosenberg, Andrew L

    2011-07-01

    The incidence of acute lung injury (ALI) in hypoxic patients undergoing surgery is currently unknown. Previous studies have identified lung protective ventilation strategies that are beneficial in the treatment of ALI. The authors sought to determine the incidence and examine the use of lung protective ventilation strategies in patients receiving anesthetics with a known history of ALI. The ventilation parameters that were used in all patients were reviewed, with an average preoperative PaO₂/Fio₂ [corrected] ratio of ≤ 300 between January 1, 2005 and July 1, 2009. This dataset was then merged with a dataset of patients screened for ALI. The median tidal volume, positive end-expiratory pressure, peak inspiratory pressures, fraction inhaled oxygen, oxygen saturation, and tidal volumes were compared between groups. A total of 1,286 patients met criteria for inclusion; 242 had a diagnosis of ALI preoperatively. Comparison of patients with ALI versus those without ALI found statistically yet clinically insignificant differences between the ventilation strategies between the groups in peak inspiratory pressures and positive end-expiratory pressure but no other category. The tidal volumes in cc/kg predicted body weight were approximately 8.7 in both groups. Peak inspiratory pressures were found to be 27.87 cm H₂O on average in the non-ALI group and 29.2 in the ALI group. Similar ventilation strategies are used between patients with ALI and those without ALI. These findings suggest that anesthesiologists are not using lung protective ventilation strategies when ventilating patients with low PaO₂/Fio₂ [corrected] ratios and ALI, and instead are treating hypoxia and ALI with higher concentrations of oxygen and peak pressures.

  18. Pathway and rate-limiting step of glyphosate degradation by Aspergillus oryzae A-F02.

    PubMed

    Fu, Gui-Ming; Chen, Yan; Li, Ru-Yi; Yuan, Xiao-Qiang; Liu, Cheng-Mei; Li, Bin; Wan, Yin

    2017-09-14

    Aspergillus oryzae A-F02, a glyphosate-degrading fungus, was isolated from an aeration tank in a pesticide factory. The pathway and rate-limiting step of glyphosate (GP) degradation were investigated through metabolite analysis. GP, aminomethylphosphonic acid (AMPA), and methylamine were detected in the fermentation liquid of A. oryzae A-F02, whereas sarcosine and glycine were not. The pathway of GP degradation in A. oryzae A-F02 was revealed: GP was first degraded into AMPA, which was then degraded into methylamine. Finally, methylamine was further degraded into other products. Investigating the effects of the exogenous addition of substrates and metabolites showed that the degradation of GP to AMPA is the rate-limiting step of GP degradation by A. oryzae A-F02. In addition, the accumulation of AMPA and methylamine did not cause feedback inhibition in GP degradation. Results showed that degrading GP to AMPA was a crucial step in the degradation of GP, which determines the degradation rate of GP by A. oryzae A-F02.

  19. Low strain, long life creep fatigue of AF2-1DA and INCO 718

    NASA Technical Reports Server (NTRS)

    Thakker, A. B.; Cowles, B. A.

    1983-01-01

    Two aircraft turbine disk alloys, GATORIZED AF2-DA and INCO 718 were evaluated for their low strain long life creep-fatigue behavior. Static (tensile and creep rupture) and cyclic properties of both alloys were characterized. The cntrolled strain LCF tests were conducted at 760 C (1400 F) and 649 C (1200 F) for AF2-1DA and INCO 718, respectively. Hold times were varied for tensile, compressive and tensile/compressive strain dwell (relaxation) tests. Stress (creep) hold behavior of AF2-1DA was also evaluated. Generally, INCO 718 exhibited more pronounced reduction in cyclic life due to hold than AF2-1DA. The percent reduction in life for both alloys for strain dwell tests was greater at low strain ranges (longer life regime). Changing hold time from 0 to 0.5, 2.0 and 15.0 min. resulted in corresponding reductions in life. The continuous cycle and cyclic/dwell initiation failure mechanism was predominantly transgranular for AF2-1DA and intergranular for INCO 718.

  20. Cardiovascular risk profile and management of atrial fibrillation in India: Real world data from RealiseAF survey.

    PubMed

    Narasimhan, C; Verma, Jagmohan Singh; Ravi Kishore, A G; Singh, Balbir; Dani, Sameer; Chawala, Kamaldeep; Haque, Azizul; Khan, Aftab; Nair, Mohan; Vora, Amit; Rajasekhar, V; Thomas, Joy M; Gupta, Anoop; Naik, Ajay; Prakash, V S; Naditch, Lisa; Gabriel Steg, P

    Atrial fibrillation (AF) is the most common sustained arrhythmia with high risk for many cardiovascular (CV) complications. Adherence to recommended management guidelines is important to avoid complications. In India, there is little knowledge on how AF is managed in real world. This is a cross-sectional study of patients in India enrolled in RealiseAF survey between February 2010 and March 2010 with a diagnosis of AF within the last 12 months. From 15 centers, 301 patients {mean age 59.9 years (14.4); 52.5% males} were recruited. AF was controlled in 50% of patients with 77 (26.7%) in sinus rhythm and 67 (23.3%) with heart rate <80beats/min. Hypertension (50.8%), valvular heart disease (40.7%), heart failure (25.9%), and diabetes (20.4%) were the most common underlying CV diseases. Increased risk for stroke (CHADS 2 score≥2) was present in 36.6%. Most of the patients (85%) were symptomatic. AF was paroxysmal, persistent, and permanent in 28.7%, 22.7%, and 34.3% respectively. In 14%, AF was diagnosed as first episode. Forty-six percent of patients had rate control, 35.2% rhythm control, 0.3% both strategies, and 18.4% received no therapy for AF before the visit. At the end of the visit, adoption to rate control strategy increased to 52.3% and patients with no therapy decreased to 7%. AF in India is not adequately controlled. Concomitant CV risk factors and risk of stroke are high. The study underscores the need for improved adoption of guideline-directed management for optimal control of AF and reducing the risk of stroke. Copyright © 2016. Published by Elsevier B.V.

  1. 46 CFR 32.56-60 - Ventilation ducts-T/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Ventilation ducts-T/ALL. 32.56-60 Section 32.56-60 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS SPECIAL EQUIPMENT, MACHINERY, AND HULL....56-60 Ventilation ducts—T/ALL. (a) Each duct for ventilation of Category A machinery spaces that...

  2. 46 CFR 32.56-60 - Ventilation ducts-T/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Ventilation ducts-T/ALL. 32.56-60 Section 32.56-60 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS SPECIAL EQUIPMENT, MACHINERY, AND HULL....56-60 Ventilation ducts—T/ALL. (a) Each duct for ventilation of Category A machinery spaces that...

  3. 46 CFR 169.315 - Ventilation (other than machinery spaces).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Ventilation (other than machinery spaces). 169.315... spaces). (a) All enclosed spaces within the vessel must be properly ventilated in a manner suitable for the purpose of the space. (b) A means must be provided to close off all vents and ventilators. (c...

  4. 46 CFR 169.315 - Ventilation (other than machinery spaces).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Ventilation (other than machinery spaces). 169.315... spaces). (a) All enclosed spaces within the vessel must be properly ventilated in a manner suitable for the purpose of the space. (b) A means must be provided to close off all vents and ventilators. (c...

  5. 46 CFR 169.315 - Ventilation (other than machinery spaces).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Ventilation (other than machinery spaces). 169.315... spaces). (a) All enclosed spaces within the vessel must be properly ventilated in a manner suitable for the purpose of the space. (b) A means must be provided to close off all vents and ventilators. (c...

  6. 46 CFR 169.315 - Ventilation (other than machinery spaces).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Ventilation (other than machinery spaces). 169.315... spaces). (a) All enclosed spaces within the vessel must be properly ventilated in a manner suitable for the purpose of the space. (b) A means must be provided to close off all vents and ventilators. (c...

  7. [Monitorization of respiratory mechanics in the ventilated patient].

    PubMed

    García-Prieto, E; Amado-Rodríguez, L; Albaiceta, G M

    2014-01-01

    Monitoring during mechanical ventilation allows the measurement of different parameters of respiratory mechanics. Accurate interpretation of these data can be useful for characterizing the situation of the different components of the respiratory system, and for guiding ventilator settings. In this review, we describe the basic concepts of respiratory mechanics, their interpretation, and their potential use in fine-tuning mechanical ventilation. Copyright © 2013 Elsevier España, S.L. y SEMICYUC. All rights reserved.

  8. Rivaroxaban vs. warfarin in Japanese patients with atrial fibrillation – the J-ROCKET AF study –.

    PubMed

    Hori, Masatsugu; Matsumoto, Masayasu; Tanahashi, Norio; Momomura, Shin-ichi; Uchiyama, Shinichiro; Goto, Shinya; Izumi, Tohru; Koretsune, Yukihiro; Kajikawa, Mariko; Kato, Masaharu; Ueda, Hitoshi; Iwamoto, Kazuya; Tajiri, Masahiro

    2012-01-01

    The global ROCKET AF study evaluated once-daily rivaroxaban vs. warfarin for stroke and systemic embolism prevention in patients with atrial fibrillation (AF). A separate trial, J-ROCKET AF, compared the safety of a Japan-specific rivaroxaban dose with warfarin administered according to Japanese guidelines in Japanese patients with AF. J-ROCKET AF was a prospective, randomized, double-blind, phase III trial. Patients (n=1,280) with non-valvular AF at increased risk for stroke were randomized to receive 15 mg once-daily rivaroxaban or warfarin dose-adjusted according to Japanese guidelines. The primary objective was to determine non-inferiority of rivaroxaban against warfarin for the principal safety outcome of major and non-major clinically relevant bleeding, in the on-treatment safety population. The primary efficacy endpoint was the composite of stroke and systemic embolism. Non-inferiority of rivaroxaban to warfarin was confirmed; the rate of the principal safety outcome was 18.04% per year in rivaroxaban-treated patients and 16.42% per year in warfarin-treated patients (hazard ratio [HR] 1.11; 95% confidence interval 0.87-1.42; P<0.001 [non-inferiority]). Intracranial hemorrhage rates were 0.8% with rivaroxaban and 1.6% with warfarin. There was a strong trend for a reduction in the rate of stroke/systemic embolism with rivaroxaban vs. warfarin (HR, 0.49; P=0.050). J-ROCKET AF demonstrated the safety of a Japan-specific rivaroxaban dose and supports bridging the global ROCKET AF results into Japanese clinical practice.

  9. Laboratory and Physical Modelling of Building Ventilation Flows

    NASA Astrophysics Data System (ADS)

    Hunt, Gary

    2001-11-01

    Heating and ventilating buildings accounts for a significant fraction of the total energy budget of cities and an immediate challenge in building physics is for the design of sustainable, low-energy buildings. Natural ventilation provides a low-energy solution as it harness the buoyancy force associated with temperature differences between the internal and external environment, and the wind to drive a ventilating flow. Modern naturally-ventilated buildings use innovative design solutions, e.g. glazed atria and solar chimneys, to enhance the ventilation and demand for these and other designs has far outstripped our understanding of the fluid mechanics within these buildings. Developing an understanding of the thermal stratification and movement of air provides a considerable challenge as the flows involve interactions between stratification and turbulence and often in complex geometries. An approach that has provided significant new insight into these flows and which has led to the development of design guidelines for architects and ventilation engineers is laboratory modelling at small-scale in water tanks combined with physical modelling. Density differences to drive the flow in simplified plexiglass models of rooms or buildings are provided by fresh and salt water solutions, and wind flow is represented by a mean flow in a flume tank. In tandom with the experiments, theoretical models that capture the essential physics of these flows have been developed in order to generalise the experimental results to a wide range of typical building geometries and operating conditions. This paper describes the application and outcomes of these modelling techniques to the study of a variety of natural ventilation flows in buildings.

  10. Winter ventilation rates at primary schools: comparison between Portugal and Finland.

    PubMed

    Canha, N; Almeida, S M; Freitas, M C; Täubel, M; Hänninen, O

    2013-01-01

    This study focused on examination of ventilation rates in classrooms with two different types of ventilation systems: natural and mechanical. Carbon dioxide (CO2) measurements were conducted in primary schools of Portugal characterized by natural ventilation and compared to Finland where mechanical ventilation is the norm. The winter period was selected since this season exerts a great influence in naturally ventilated classrooms, where opening of windows and doors occurs due to outdoor atmospheric conditions. The ventilation rates were calculated by monitoring CO2 concentrations generated by the occupants (used as a tracer gas) and application of the buildup phase method. A comparison between both countries' results was conducted with respect to ventilation rates and how these levels corresponded to national regulatory standards. Finnish primary schools (n = 2) registered a mean ventilation rate of 13.3 L/s per person, which is higher than the recommended ventilation standards. However, the Finnish classroom that presented the lowest ventilation rate (7.2 L/s per person) displayed short-term CO2 levels above 1200 ppm, which is the threshold limit value (TLV) recommended by national guidelines. The Portuguese classrooms (n = 2) showed low ventilation rates with mean values of 2.4 L/s per person, which is markedly lower than the minimum recommended value of 7 L/s per person as defined by ASHRAE and 20% less than the REHVA minimum of 3 L/s per person. Carbon dioxide levels of 1000 ppm, close to the TLV of 1200 ppm, were also reached in both Portuguese classrooms studied. The situation in Portugal indicates a potentially serious indoor air quality problem and strengthens the need for intervention to improve ventilation rates in naturally ventilated classrooms.

  11. Prevention of ventilator-associated pneumonia.

    PubMed

    Oliveira, J; Zagalo, C; Cavaco-Silva, P

    2014-01-01

    Invasive mechanical ventilation (IMV) represents a risk factor for the development of ventilator-associated pneumonia (VAP), which develops at least 48h after admission in patients ventilated through tracheostomy or endotracheal intubation. VAP is the most frequent intensive-care-unit (ICU)-acquired infection among patients receiving IMV. It contributes to an increase in hospital mortality, duration of MV and ICU and length of hospital stay. Therefore, it worsens the condition of the critical patient and increases the total cost of hospitalization. The introduction of preventive measures has become imperative, to ensure control and to reduce the incidence of VAP. Preventive measures focus on modifiable risk factors, mediated by non-pharmacological and pharmacological evidence based strategies recommended by guidelines. These measures are intended to reduce the risk associated with endotracheal intubation and to prevent microaspiration of pathogens to the lower airways. Copyright © 2013 Sociedade Portuguesa de Pneumologia. Published by Elsevier España. All rights reserved.

  12. Analysis of radon reduction and ventilation systems in uranium mines in China.

    PubMed

    Hu, Peng-hua; Li, Xian-jie

    2012-09-01

    Mine ventilation is the most important way of reducing radon in uranium mines. At present, the radon and radon progeny levels in Chinese uranium mines where the cut and fill stoping method is used are 3-5 times higher than those in foreign uranium mines, as there is not much difference in the investments for ventilation protection between Chinese uranium mines and international advanced uranium mines with compaction methodology. In this paper, through the analysis of radon reduction and ventilation systems in Chinese uranium mines and the comparison of advantages and disadvantages between a variety of ventilation systems in terms of radon control, the authors try to illustrate the reasons for the higher radon and radon progeny levels in Chinese uranium mines and put forward some problems in three areas, namely the theory of radon control and ventilation systems, radon reduction ventilation measures and ventilation management. For these problems, this paper puts forward some proposals regarding some aspects, such as strengthening scrutiny, verifying and monitoring the practical situation, making clear ventilation plans, strictly following the mining sequence, promoting training of ventilation staff, enhancing ventilation system management, developing radon reduction ventilation technology, purchasing ventilation equipment as soon as possible in the future, and so on.

  13. Ventilation practices in the neonatal intensive care unit: a cross-sectional study.

    PubMed

    van Kaam, Anton H; Rimensberger, Peter C; Borensztajn, Dorine; De Jaegere, Anne P

    2010-11-01

    To assess current ventilation practices in newborn infants. We conducted a 2-point cross-sectional study in 173 European neonatal intensive care units, including 535 infants (mean gestational age 28 weeks and birth weight 1024 g). Patient characteristics, ventilator settings, and measurements were collected bedside from endotracheally ventilated infants. A total of 457 (85%) patients were conventionally ventilated. Time cycled pressure-limited ventilation was used in 59% of these patients, most often combined with synchronized intermittent mandatory ventilation (51%). Newer conventional ventilation modes like volume targeted and pressure support ventilation were used in, respectively, 9% and 7% of the patients. The mean tidal volume, measured in 84% of the conventionally ventilated patients, was 5.7 ± 2.3 ml/kg. The mean positive end-expiratory pressure was 4.5 ± 1.1 cmH(2)O and rarely exceeded 7 cmH(2)O. Time cycled pressure-limited ventilation is the most commonly used mode in neonatal ventilation. Tidal volumes are usually targeted between 4 to 7 mL/kg and positive end-expiratory pressure between 4 to 6 cmH(2)O. Newer ventilation modes are only used in a minority of patients. Copyright © 2010 Mosby, Inc. All rights reserved.

  14. Tunnel Ventilation Control Using Reinforcement Learning Methodology

    NASA Astrophysics Data System (ADS)

    Chu, Baeksuk; Kim, Dongnam; Hong, Daehie; Park, Jooyoung; Chung, Jin Taek; Kim, Tae-Hyung

    The main purpose of tunnel ventilation system is to maintain CO pollutant concentration and VI (visibility index) under an adequate level to provide drivers with comfortable and safe driving environment. Moreover, it is necessary to minimize power consumption used to operate ventilation system. To achieve the objectives, the control algorithm used in this research is reinforcement learning (RL) method. RL is a goal-directed learning of a mapping from situations to actions without relying on exemplary supervision or complete models of the environment. The goal of RL is to maximize a reward which is an evaluative feedback from the environment. In the process of constructing the reward of the tunnel ventilation system, two objectives listed above are included, that is, maintaining an adequate level of pollutants and minimizing power consumption. RL algorithm based on actor-critic architecture and gradient-following algorithm is adopted to the tunnel ventilation system. The simulations results performed with real data collected from existing tunnel ventilation system and real experimental verification are provided in this paper. It is confirmed that with the suggested controller, the pollutant level inside the tunnel was well maintained under allowable limit and the performance of energy consumption was improved compared to conventional control scheme.

  15. Transition from in-hospital ventilation to home ventilation: process description and quality indicators

    PubMed Central

    Kastrup, Marc; Tittmann, Benjamin; Sawatzki, Tanja; Gersch, Martin; Vogt, Charlotte; Rosenthal, Max; Rosseau, Simone; Spies, Claudia

    2017-01-01

    The current demographic development of our society results in an increasing number of elderly patients with chronic diseases being treated in the intensive care unit. A possible long-term consequence of such a treatment is that patients remain dependent on certain invasive organ support systems, such as long-term ventilator dependency. The main goal of this project is to define the transition process between in-hospital and out of hospital (ambulatory) ventilator support. A further goal is to identify evidence-based quality indicators to help define and describe this process. This project describes an ideal sequence of processes (process chain), based on the current evidence from the literature. Besides the process chain, key data and quality indicators were described in detail. Due to the limited project timeline, these indicators were not extensively tested in the clinical environment. The results of this project may serve as a solid basis for proof of feasibility and proof of concept investigations, optimize the transition process of ventilator-dependent patients from a clinical to an ambulatory setting, as well as reduce the rate of emergency re-admissions. PMID:29308061

  16. Low tidal volume mechanical ventilation against no ventilation during cardiopulmonary bypass heart surgery (MECANO): study protocol for a randomized controlled trial.

    PubMed

    Nguyen, Lee S; Merzoug, Messaouda; Estagnasie, Philippe; Brusset, Alain; Law Koune, Jean-Dominique; Aubert, Stephane; Waldmann, Thierry; Grinda, Jean-Michel; Gibert, Hadrien; Squara, Pierre

    2017-12-02

    Postoperative pulmonary complications are a leading cause of morbidity and mortality after cardiac surgery. There are no recommendations on mechanical ventilation associated with cardiopulmonary bypass (CPB) during surgery and anesthesiologists perform either no ventilation (noV) at all during CPB or maintain low tidal volume (LTV) ventilation. Indirect evidence points towards better pulmonary outcomes when LTV is performed but no large-scale prospective trial has yet been published in cardiac surgery. The MECANO trial is a single-center, double-blind, randomized, controlled trial comparing two mechanical ventilation strategies, noV and LTV, during cardiac surgery with CPB. In total, 1500 patients are expected to be included, without any restrictions. They will be randomized between noV and LTV on a 1:1 ratio. The noV group will receive no ventilation during CPB. The LTV group will receive 5 breaths/minute with a tidal volume of 3 mL/kg and positive end-expiratory pressure of 5 cmH2O. The primary endpoint will be a composite of all-cause mortality, early respiratory failure defined as a ratio of partial pressure of oxygen/fraction of inspired oxygen <200 mmHg at 1 hour after arrival in the ICU, heavy oxygenation support (defined as a patient requiring either non-invasive ventilation, mechanical ventilation or high-flow oxygen) at 2 days after arrival in the ICU or ventilator-acquired pneumonia defined by the Center of Disease Control. Lung recruitment maneuvers will be performed in the noV and LTV groups at the end of surgery and at arrival in ICU with an insufflation at +30 cmH20 for 5 seconds. Secondary endpoints are those composing the primary endpoint with the addition of pneumothorax, CPB duration, quantity of postoperative bleeding, red blood cell transfusions, revision surgery requirements, length of stay in the ICU and in the hospital and total hospitalization costs. Patients will be followed until hospital discharge. The MECANO trial is the first of

  17. [Percutaneous tracheostomy in the ventilated patient].

    PubMed

    Añón, J M; Araujo, J B; Escuela, M P; González-Higueras, E

    2014-04-01

    The medical indications of tracheostomy comprise the alleviation of upper airway obstruction; the prevention of laryngeal and upper airway damage due to prolonged translaryngeal intubation in patients subjected to prolonged mechanical ventilation; and the facilitation of airway access for the removal of secretions. Since 1985, percutaneous tracheostomy (PT) has gained widespread acceptance as a method for creating a surgical airway in patients requiring long-term mechanical ventilation. Since then, several comparative trials of PT and surgical tracheostomy have been conducted, and new techniques for PT have been developed. The use of percutaneous dilatation techniques under bronchoscopic control are now increasingly popular throughout the world. Tracheostomy should be performed as soon as the need for prolonged intubation is identified. However a validated model for the prediction of prolonged mechanical ventilation is not available, and the timing of tracheostomy should be individualized. The present review analyzes the state of the art of PT in mechanically ventilated patients--this being regarded by many as the technique of choice in performing tracheostomy in critically ill patients. Copyright © 2012 Elsevier España, S.L. and SEMICYUC. All rights reserved.

  18. TU-A-12A-02: Novel Lung Ventilation Imaging with Single Energy CT After Single Inhalation of Xenon: Comparison with SPECT Ventilation Images

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

    Negahdar, M; Yamamoto, T; Shultz, D

    Purpose: We propose a novel lung functional imaging method to determine the spatial distribution of xenon (Xe) gas in a single inhalation as a measure of regional ventilation. We compare Xe-CT ventilation to single-photon emission CT (SPECT) ventilation, which is the current clinical reference. Regional lung ventilation information may be useful for the diagnosis and monitoring of pulmonary diseases such as COPD, radiotherapy planning, and assessing the progression of toxicity after radiation therapy. Methods: In an IRB-approved clinical study, Xe-CT and SPECT ventilation scans were acquired for three patients including one patient with severe emphysema and two lung cancer patientsmore » treated with radiotherapy. For Xe- CT, we acquired two breath-hold single energy CT images of the entire lung with inspiration of 100% O2 and a mixture of 70% Xe and 30% O2, respectively. A video biofeedback system was used to achieve reproducible breath-holds. We used deformable image registration to align the breathhold images with each other to accurately subtract them, producing a map of the distribution of Xe as a surrogate of lung ventilation. We divided each lung into twelve parts and correlated the Hounsfield unit (HU) enhancement at each part with the SPECT ventilation count of the corresponding part of the lung. Results: The mean of the Pearson linear correlation coefficient values between the Xe-CT and ventilation SPECT count for all three patients were 0.62 (p<0.01). The Xe-CT image had a higher resolution than SPECT, and did not show central airway deposition artifacts that were present in the SPECT image. Conclusion: We developed a rapid, safe, clinically practical, and potentially widely accessible method for regional lung functional imaging. We demonstrated strong correlations between the Xe-CT ventilation image and SPECT ventilation image as the clinical reference. This ongoing study will investigate more patients to confirm this finding.« less

  19. Confined space ventilation by shipyard welders: observed use and effectiveness.

    PubMed

    Pouzou, Jane G; Warner, Chris; Neitzel, Richard L; Croteau, Gerry A; Yost, Michael G; Seixas, Noah S

    2015-01-01

    Shipbuilding involves intensive welding activities within enclosed and confined spaces, and although ventilation is commonly used in the industry, its use and effectiveness has not been adequately documented. Workers engaged in welding in enclosed or confined spaces in two shipyards were observed for their use of ventilation and monitored for their exposure to particulate matter. The type of ventilation in use, its placement and face velocity, the movement of air within the space, and other ventilation-related parameters were recorded, along with task characteristics such as the type of welding, the welder's position, and the configuration of the space. Mechanical ventilation was present in about two-thirds of the 65 welding scenarios observed, with exhaust ventilation used predominantly in one shipyard and supply blowers predominantly in the other. Welders were observed working in apparent dead-spaces within the room in 53% of the cases, even where ventilation was in use. Respiratory protection was common in the two shipyards, observed in use in 77 and 100% of the cases. Welding method, the proximity of the welder's head to the fume, and air mixing were found to be significantly associated with the welder's exposure, while other characteristics of dilution ventilation did not produce appreciable differences in exposure level. These parameters associated with exposure reduction can be assessed subjectively and are thus good candidates for training on effective ventilation use during hot work in confined spaces. Ventilation used in confined space welding is often inadequate for controlling exposure to welding fume. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  20. Identifying Potential Ventilator Auto-Triggering Among Organ Procurement Organization Referrals.

    PubMed

    Henry, Nicholas R; Russian, Christopher J; Nespral, Joseph

    2016-06-01

    Ventilator auto-trigger is the delivery of an assisted mechanical ventilated breath over the set ventilator frequency in the absence of a spontaneous inspiratory effort and can be caused by inappropriate ventilator trigger sensitivity. Ventilator auto-trigger can be misinterpreted as a spontaneous breath and has the potential to delay or prevent brain death testing and confuse health-care professionals and/or patient families. To determine the frequency of organ donor referrals from 1 Organ Procurement Organization (OPO) that could benefit from an algorithm designed to assist organ recovery coordinators to identify and correct ventilator auto-triggering. This retrospective analysis evaluated documentation of organ donor referrals from 1 OPO in central Texas during the 2013 calendar year that resulted in the withdrawal of care by the patient's family and the recovery of organs. The frequency of referrals that presented with absent brain stem reflexes except for additional respirations over the set ventilator rate was determined to assess for the need of the proposed algorithm. Documentation of 672 organ procurement organization referrals was evaluated. Documentation from 42 referrals that resulted in the withdrawal of care and 21 referrals that resulted in the recovery of organs were identified with absent brain stem reflexes except for spontaneous respirations on the mechanical ventilator. As a result, an algorithm designed to identify and correct ventilator auto-trigger could have been used 63 times during the 2013 calendar year. © 2016, NATCO.

  1. Heliox Improves Carbon Dioxide Removal during Lung Protective Mechanical Ventilation.

    PubMed

    Beurskens, Charlotte J; Brevoord, Daniel; Lagrand, Wim K; van den Bergh, Walter M; Vroom, Margreeth B; Preckel, Benedikt; Horn, Janneke; Juffermans, Nicole P

    2014-01-01

    Introduction. Helium is a noble gas with low density and increased carbon dioxide (CO2) diffusion capacity. This allows lower driving pressures in mechanical ventilation and increased CO2 diffusion. We hypothesized that heliox facilitates ventilation in patients during lung-protective mechanical ventilation using low tidal volumes. Methods. This is an observational cohort substudy of a single arm intervention study. Twenty-four ICU patients were included, who were admitted after a cardiac arrest and mechanically ventilated for 3 hours with heliox (50% helium; 50% oxygen). A fixed protective ventilation protocol (6 mL/kg) was used, with prospective observation for changes in lung mechanics and gas exchange. Statistics was by Bonferroni post-hoc correction with statistical significance set at P < 0.017. Results. During heliox ventilation, respiratory rate decreased (25 ± 4 versus 23 ± 5 breaths min(-1), P = 0.010). Minute volume ventilation showed a trend to decrease compared to baseline (11.1 ± 1.9 versus 9.9 ± 2.1 L min(-1), P = 0.026), while reducing PaCO2 levels (5.0 ± 0.6 versus 4.5 ± 0.6 kPa, P = 0.011) and peak pressures (21.1 ± 3.3 versus 19.8 ± 3.2 cm H2O, P = 0.024). Conclusions. Heliox improved CO2 elimination while allowing reduced minute volume ventilation in adult patients during protective mechanical ventilation.

  2. Controlled invasive mechanical ventilation strategies in obese patients undergoing surgery.

    PubMed

    Maia, Lígia de Albuquerque; Silva, Pedro Leme; Pelosi, Paolo; Rocco, Patricia Rieken Macedo

    2017-06-01

    The obesity prevalence is increasing in surgical population. As the number of obese surgical patients increases, so does the demand for mechanical ventilation. Nevertheless, ventilatory strategies in this population are challenging, since obesity results in pathophysiological changes in respiratory function. Areas covered: We reviewed the impact of obesity on respiratory system and the effects of controlled invasive mechanical ventilation strategies in obese patients undergoing surgery. To date, there is no consensus regarding the optimal invasive mechanical ventilation strategy for obese surgical patients, and no evidence that possible intraoperative beneficial effects on oxygenation and mechanics translate into better postoperative pulmonary function or improved outcomes. Expert commentary: Before determining the ideal intraoperative ventilation strategy, it is important to analyze the pathophysiology and comorbidities of each obese patient. Protective ventilation with low tidal volume, driving pressure, energy, and mechanical power should be employed during surgery; however, further studies are required to clarify the most effective ventilation strategies, such as the optimal positive end-expiratory pressure and whether recruitment maneuvers minimize lung injury. In this context, an ongoing trial of intraoperative ventilation in obese patients (PROBESE) should help determine the mechanical ventilation strategy that best improves clinical outcome in patients with body mass index≥35kg/m 2 .

  3. Innovative ventilation system for animal anatomy laboratory

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

    Lacey, D.R.; Smith, D.C.

    1997-04-01

    A unique ventilation system was designed and built to reduce formaldehyde fumes in the large animal anatomy lab at the Vet Medical Center at Cornell University. The laboratory includes four rooms totaling 5,500 ft{sup 2}. The main room has 2,300 ft{sup 2} and houses the laboratory where up to 60 students dissect as many as 12 horses at a time. Other rooms are a cold storage locker, an animal preparation room and a smaller lab for specialized instruction. The large animal anatomy laboratory has a history of air quality complaints despite a fairly high ventilation rate of over 10 airmore » changes/hour. The horses are embalmed, creating a voluminous source of formaldehyde and phenol vapors. Budget constraints and increasingly stringent exposure limits for formaldehyde presented a great challenge to design a ventilation system that yields acceptable air quality. The design solution included two innovative elements: air-to-air heat recovery, and focused ventilation.« less

  4. Magnetic Resonance Imaging of Ventilation and Perfusion in the Lung

    NASA Technical Reports Server (NTRS)

    Prisk, Gordon Kim (Inventor); Hopkins, Susan Roberta (Inventor); Pereira De Sa, Rui Carlos (Inventor); Theilmann, Rebecca Jean (Inventor); Buxton, Richard Bruce (Inventor); Cronin, Matthew Vincent (Inventor)

    2017-01-01

    Methods, devices, and systems are disclosed for implementing a fully quantitative non-injectable contrast proton MRI technique to measure spatial ventilation-perfusion (VA/Q) matching and spatial distribution of ventilation and perfusion. In one aspect, a method using MRI to characterize ventilation and perfusion in a lung includes acquiring an MR image of the lung having MR data in a voxel and obtaining a breathing frequency parameter, determining a water density value, a specific ventilation value, and a perfusion value in at least one voxel of the MR image based on the MR data and using the water density value to determine an air content value, and determining a ventilation-perfusion ratio value that is the product of the specific ventilation value, the air content value, the inverse of the perfusion value, and the breathing frequency.

  5. Technology for noninvasive mechanical ventilation: looking into the black box

    PubMed Central

    Navajas, Daniel; Montserrat, Josep M.

    2016-01-01

    Current devices for providing noninvasive respiratory support contain sensors and built-in intelligence for automatically modifying ventilation according to the patient's needs. These devices, including automatic continuous positive airway pressure devices and noninvasive ventilators, are technologically complex and offer a considerable number of different modes of ventilation and setting options, the details of which are sometimes difficult to capture by the user. Therefore, better predicting and interpreting the actual performance of these ventilation devices in clinical application requires understanding their functioning principles and assessing their performance under well controlled bench test conditions with simulated patients. This concise review presents an updated perspective of the theoretical basis of intelligent continuous positive airway pressure and noninvasive ventilation devices, and of the tools available for assessing how these devices respond under specific ventilation phenotypes in patients requiring breathing support. PMID:27730162

  6. Treatment Guidelines of Atrial Fibrillation (AFib or AF)

    MedlinePlus

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More Treatment Guidelines of Atrial Fibrillation (AFib or AF) Updated:Jun 28,2017 What are the treatment guidelines for atrial fibrillation? Medical guidelines are written by ...

  7. AfAP2-1, An Age-Dependent Gene of Aechmea fasciata, Responds to Exogenous Ethylene Treatment

    PubMed Central

    Lei, Ming; Li, Zhi-Ying; Wang, Jia-Bin; Fu, Yun-Liu; Ao, Meng-Fei; Xu, Li

    2016-01-01

    The Bromeliaceae family is one of the most morphologically diverse families with a pantropical distribution. To schedule an appropriate flowering time for bromeliads, ethylene is commonly used to initiate flower development in adult plants. However, the mechanism by which ethylene induces flowering in adult bromeliads remains unknown. Here, we identified an APETALA2 (AP2)-like gene, AfAP2-1, in Aechmea fasciata. AfAP2-1 contains two AP2 domains and is a nuclear-localized protein. It functions as a transcriptional activator, and the activation domain is located in the C-terminal region. The expression level of AfAP2-1 is higher in juvenile plants than in adult plants, and the AfAP2-1 transcript level was rapidly and transiently reduced in plants treated with exogenous ethylene. Overexpression of AfAP2-1 in Arabidopsis thaliana results in an extremely delayed flowering phenotype. These results suggested that AfAP2-1 responds to ethylene and is a putative age-dependent flowering regulator in A. fasciata. PMID:26927090

  8. Older patients with late-stage COPD: Their illness experiences and involvement in decision-making regarding mechanical ventilation and noninvasive ventilation.

    PubMed

    Jerpseth, Heidi; Dahl, Vegard; Nortvedt, Per; Halvorsen, Kristin

    2018-02-01

    To explore the illness experiences of older patients with late-stage chronic obstructive pulmonary disease and to develop knowledge about how patients perceive their preferences to be taken into account in decision-making processes concerning mechanical ventilation and/or noninvasive ventilation. Decisions about whether older patients with late-stage chronic obstructive pulmonary disease will benefit from noninvasive ventilation treatment or whether the time has come for palliative treatment are complicated, both medically and ethically. Knowledge regarding patients' values and preferences concerning ventilation support is crucial yet often lacking. Qualitative design with a hermeneutic-phenomenological approach. The data consist of qualitative in-depth interviews with 12 patients from Norway diagnosed with late-stage chronic obstructive pulmonary disease. The data were analysed within the three interpretative contexts described by Kvale and Brinkmann. The participants described their lives as fragile and burdensome, frequently interrupted by unpredictable and frightening exacerbations. They lacked information about their diagnosis and prognosis and were often not included in decisions about noninvasive ventilation or mechanical ventilation. Findings indicate that these patients are highly vulnerable and have complex needs in terms of nursing care and medical treatment. Moreover, they need access to proactive advanced care planning and an opportunity to discuss their wishes for treatment and care. To provide competent care for these patients, healthcare personnel must be aware of how patients experience being seriously ill. Advanced care planning and shared decision-making should be initiated alongside the curative treatment. © 2017 John Wiley & Sons Ltd.

  9. 24 CFR 3280.103 - Light and ventilation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Light and ventilation. 3280.103... Light and ventilation. (a) Lighting. Each habitable room shall be provided with exterior windows and/or..., bathrooms, toilet compartments, laundry areas, and utility rooms may be provided with artificial light in...

  10. 24 CFR 3280.103 - Light and ventilation.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Light and ventilation. 3280.103... Light and ventilation. (a) Lighting. Each habitable room shall be provided with exterior windows and/or..., bathrooms, toilet compartments, laundry areas, and utility rooms may be provided with artificial light in...

  11. 24 CFR 3280.103 - Light and ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Light and ventilation. 3280.103... Light and ventilation. (a) Lighting. Each habitable room shall be provided with exterior windows and/or..., bathrooms, toilet compartments, laundry areas, and utility rooms may be provided with artificial light in...

  12. 24 CFR 3280.103 - Light and ventilation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Light and ventilation. 3280.103... Light and ventilation. (a) Lighting. Each habitable room shall be provided with exterior windows and/or..., bathrooms, toilet compartments, laundry areas, and utility rooms may be provided with artificial light in...

  13. 24 CFR 3280.103 - Light and ventilation.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Light and ventilation. 3280.103... Light and ventilation. (a) Lighting. Each habitable room shall be provided with exterior windows and/or..., bathrooms, toilet compartments, laundry areas, and utility rooms may be provided with artificial light in...

  14. 46 CFR 190.15-15 - Ventilation for living spaces and quarters.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Ventilation for living spaces and quarters. 190.15-15... VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-15 Ventilation for living spaces and quarters. (a) All living spaces shall be adequately ventilated in a manner suitable to the purpose of the space...

  15. 46 CFR 190.15-15 - Ventilation for living spaces and quarters.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Ventilation for living spaces and quarters. 190.15-15... VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-15 Ventilation for living spaces and quarters. (a) All living spaces shall be adequately ventilated in a manner suitable to the purpose of the space...

  16. 46 CFR 190.15-15 - Ventilation for living spaces and quarters.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Ventilation for living spaces and quarters. 190.15-15... VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-15 Ventilation for living spaces and quarters. (a) All living spaces shall be adequately ventilated in a manner suitable to the purpose of the space...

  17. 46 CFR 190.15-15 - Ventilation for living spaces and quarters.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Ventilation for living spaces and quarters. 190.15-15... VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-15 Ventilation for living spaces and quarters. (a) All living spaces shall be adequately ventilated in a manner suitable to the purpose of the space...

  18. 46 CFR 190.15-15 - Ventilation for living spaces and quarters.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Ventilation for living spaces and quarters. 190.15-15... VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-15 Ventilation for living spaces and quarters. (a) All living spaces shall be adequately ventilated in a manner suitable to the purpose of the space...

  19. RESIDENTIAL VENTILATION STUDY

    EPA Science Inventory

    This project evaluated the effectiveness, first costs and operational costs of various types of residential ventilation systems in three different climates in the U.S. The Agency, through its Energy Star Program, recommends that builders construct homes that are energy efficient ...

  20. Replicating human expertise of mechanical ventilation waveform analysis in detecting patient-ventilator cycling asynchrony using machine learning.

    PubMed

    Gholami, Behnood; Phan, Timothy S; Haddad, Wassim M; Cason, Andrew; Mullis, Jerry; Price, Levi; Bailey, James M

    2018-06-01

    - Acute respiratory failure is one of the most common problems encountered in intensive care units (ICU) and mechanical ventilation is the mainstay of supportive therapy for such patients. A mismatch between ventilator delivery and patient demand is referred to as patient-ventilator asynchrony (PVA). An important hurdle in addressing PVA is the lack of a reliable framework for continuously and automatically monitoring the patient and detecting various types of PVA. - The problem of replicating human expertise of waveform analysis for detecting cycling asynchrony (i.e., delayed termination, premature termination, or none) was investigated in a pilot study involving 11 patients in the ICU under invasive mechanical ventilation. A machine learning framework is used to detect cycling asynchrony based on waveform analysis. - A panel of five experts with experience in PVA evaluated a total of 1377 breath cycles from 11 mechanically ventilated critical care patients. The majority vote was used to label each breath cycle according to cycling asynchrony type. The proposed framework accurately detected the presence or absence of cycling asynchrony with sensitivity (specificity) of 89% (99%), 94% (98%), and 97% (93%) for delayed termination, premature termination, and no cycling asynchrony, respectively. The system showed strong agreement with human experts as reflected by the kappa coefficients of 0.90, 0.91, and 0.90 for delayed termination, premature termination, and no cycling asynchrony, respectively. - The pilot study establishes the feasibility of using a machine learning framework to provide waveform analysis equivalent to an expert human. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Integrated Stress Response Mediates Epithelial Injury in Mechanical Ventilation.

    PubMed

    Dolinay, Tamas; Himes, Blanca E; Shumyatcher, Maya; Lawrence, Gladys Gray; Margulies, Susan S

    2017-08-01

    Ventilator-induced lung injury (VILI) is a severe complication of mechanical ventilation that can lead to acute respiratory distress syndrome. VILI is characterized by damage to the epithelial barrier with subsequent pulmonary edema and profound hypoxia. Available lung-protective ventilator strategies offer only a modest benefit in preventing VILI because they cannot impede alveolar overdistension and concomitant epithelial barrier dysfunction in the inflamed lung regions. There are currently no effective biochemical therapies to mitigate injury to the alveolar epithelium. We hypothesize that alveolar stretch activates the integrated stress response (ISR) pathway and that the chemical inhibition of this pathway mitigates alveolar barrier disruption during stretch and mechanical ventilation. Using our established rat primary type I-like alveolar epithelial cell monolayer stretch model and in vivo rat mechanical ventilation that mimics the alveolar overdistension seen in acute respiratory distress syndrome, we studied epithelial responses to mechanical stress. Our studies revealed that the ISR signaling pathway is a key modulator of epithelial permeability. We show that prolonged epithelial stretch and injurious mechanical ventilation activate the ISR, leading to increased alveolar permeability, cell death, and proinflammatory signaling. Chemical inhibition of protein kinase RNA-like endoplasmic reticulum kinase, an upstream regulator of the pathway, resulted in decreased injury signaling and improved barrier function after prolonged cyclic stretch and injurious mechanical ventilation. Our results provide new evidence that therapeutic targeting of the ISR can mitigate VILI.

  2. Home mechanical ventilation in Canada: a national survey.

    PubMed

    Rose, Louise; McKim, Douglas A; Katz, Sherri L; Leasa, David; Nonoyama, Mika; Pedersen, Cheryl; Goldstein, Roger S; Road, Jeremy D

    2015-05-01

    No comprehensive Canadian national data describe the prevalence of and service provision for ventilator-assisted individuals living at home, data critical to health-care system planning for appropriate resourcing. Our objective was to generate national data profiling service providers, users, types of services, criteria for initiation and monitoring, ventilator servicing arrangements, education, and barriers to home transition. Eligible providers delivering services to ventilator-assisted individuals (adult and pediatric) living at home were identified by our national provider inventory and referrals from other providers. The survey was administered via a web link from August 2012 to April 2013. The survey response rate was 152/171 (89%). We identified 4,334 ventilator-assisted individuals: an estimated prevalence of 12.9/100,000 population, with 73% receiving noninvasive ventilation (NIV) and 18% receiving intermittent mandatory ventilation (9% not reported). Services were delivered by 39 institutional providers and 113 community providers. We identified variation in initiation criteria for NIV, with polysomnography demonstrating nocturnal hypoventilation (57%), daytime hypercapnia (38%), and nocturnal hypercapnia (32%) as the most common criteria. Various models of ventilator servicing were reported. Most providers (64%) stated that caregiver competency was a prerequisite for home discharge; however, repeated competency assessment and retraining were offered by only 45%. Important barriers to home transition were: insufficient funding for paid caregivers, equipment, and supplies; a shortage of paid caregivers; and negotiating public funding arrangements. Ventilatory support in the community appears well-established, with most individuals managed with NIV. Although caregiver competency is a prerequisite to discharge, ongoing assessment and retraining were infrequent. Funding and caregiver availability were important barriers to home transition. Copyright © 2015

  3. A Specific Antibody to Neuropeptide AF1 (KNEFIRFamide) Recognizes a Small Subset of Neurons in Ascaris suum: Differences from Caenorhabditis elegans

    PubMed Central

    Sithigorngul, Paisarn; Jarecki, Jessica L.; Stretton, Antony O.W.

    2016-01-01

    A monoclonal antibody, AF1-003, highly specific to the Ascaris suum neuropeptide AF1 (KNEFIRFamide), was generated. This antibody binds strongly to AF1 and extremely weakly to other peptides with C-terminal FIR-Famide: AF5 (SGKPTFIRFamide), AF6 (FIRFamide), and AF7 (AGPRFIRFamide). It does not recognize 35 other AF (A. suum FMRFamide-like) peptides at the highest concentration tested, nor does it recognize FMRFamide. When crude peptide extracts of A. suum are fractionated by two-step HPLC, the only fractions recognized by AF1-003 are those comigrating with synthetic AF1. By immunocytochemistry, antibody AF1-003 recognizes a small subset of the 298 neurons of A. suum: these include the paired URX and RIP neurons, two pairs of lateral ganglion neurons in the head, and the unpaired PQR and PDA or -B tail neurons that send processes to the head along the dorsal and ventral nerve cords, respectively. AF1 immunoreactivity is also seen in three pairs of pharyngeal neurons. Mass spectroscopy (MS) shows the presence of AF1 in the head, pharynx, and dorsal and ventral nerve cords. In A. suum, the neurons that contain AF1 show little overlap with neurons that express green fluorescent protein constructs targeting the flp-8 gene, which encodes AF1 in Caenorhabditis elegans (Kim and Li [2004] J. Comp. Neurol. 475:540– 550); the URX neurons express AF1 in both species, but, in C. elegans, flp-8 expression was not detected in RIP, PQR, and PDA or -B or in the pharynx. Other, less specific monoclonal antibodies recognize AF1, as well as other peptides to differing degrees; these antibodies are useful reagents for determination of neuronal morphology. PMID:21452223

  4. Personalizing mechanical ventilation for acute respiratory distress syndrome.

    PubMed

    Berngard, S Clark; Beitler, Jeremy R; Malhotra, Atul

    2016-03-01

    Lung-protective ventilation with low tidal volumes remains the cornerstone for treating patient with acute respiratory distress syndrome (ARDS). Personalizing such an approach to each patient's unique physiology may improve outcomes further. Many factors should be considered when mechanically ventilating a critically ill patient with ARDS. Estimations of transpulmonary pressures as well as individual's hemodynamics and respiratory mechanics should influence PEEP decisions as well as response to therapy (recruitability). This summary will emphasize the potential role of personalized therapy in mechanical ventilation.

  5. Using Hyperpolarized 129Xe MRI to Quantify the Pulmonary Ventilation Distribution

    PubMed Central

    He, Mu; Driehuys, Bastiaan; Que, Loretta G.; Huang, Yuh-Chin T.

    2017-01-01

    Background Ventilation heterogeneity is impossible to detect with spirometry. Alternatively, pulmonary ventilation can be imaged 3-dimensionally using inhaled 129Xe MRI. To date such images have been quantified primarily based on ventilation defects. Here, we introduce a robust means to transform 129Xe MRI scans such that the underlying ventilation distribution and its heterogeneity can be quantified. Methods Quantitative 129Xe ventilation MRI was conducted in 12 younger (24.7±5.2 yrs), and 10 older (62.2±7.2 yrs) healthy individuals, as well as 9 younger (25.9±6.4 yrs) and 10 older (63.2±6.1 yrs) asthmatics. The younger healthy population was used to establish a reference ventilation distribution and thresholds for 6 intensity bins. These were used to display and quantify regions of ventilation defect (VDR), low ventilation (LVR) and high ventilation (HVR). Results The ventilation distribution in young subjects was roughly Gaussian with a mean and SD of 0.52±0.18, resulting in VDR=2.1±1.3%, LVR=15.6±5.4% and HVR=17.4±3.1%. Older healthy volunteers exhibited a significantly right-skewed distribution (0.46±0.20, p=0.034), resulting in significantly increased VDR (7.0±4.8%, p=0.008) and LVR (24.5±11.5%, p=0.025). In the asthmatics, VDR and LVR increased in the older population, and HVR was significantly reduced (13.5±4.6% vs 18.9±4.5%, p=0.009). Quantitative 129Xe MRI also revealed different ventilation distribution patterns in response to albuterol in two asthmatics with normal FEV1. Conclusions Quantitative 129Xe MRI provides a robust and objective means to display and quantify the pulmonary ventilation distribution, even in subjects who have airway function impairment not appreciated by spirometry. PMID:27617823

  6. An Evaluation of the Impacts of AF-M315E Propulsion Systems for Varied Mission Applications

    NASA Technical Reports Server (NTRS)

    Deans, Matthew C.; Oleson, Steven R.; Fittje, James; Colozza, Anthony; Packard, Tom; Gyekenyesi, John; McLean, Christopher H.; Spores, Ronald A.

    2015-01-01

    The purpose of the AF-M315E COMPASS study is to identify near-term (3-5 years) and long term (5 years +) opportunities for infusion, specifically the thruster and associated component technologies being developed as part of the GPIM project. Develop design reference missions which show the advantages of the AF-M315E green propulsion system. Utilize a combination of past COMPASS designs and selected new designs to demonstrate AF-M315E advantages. Use the COMPASS process to show the puts and takes of using AF-M315E at the integrated system level.

  7. Effects of repeated administration of (-)-nicotine on AF64A-induced learning and memory impairment in rats.

    PubMed

    Hiramatsu, M; Yamatsu, T; Kameyama, T; Nabeshima, T

    2002-03-01

    It has been reported that pretreatment with (-)-nicotine prevents glutamate- and amyloid beta protein (Abeta)-induced cytotoxicity in vitro. However, few studies on the neuroprotective effects of (-)-nicotine in vivo have been reported. We examined whether repeated administration of (-)-nicotine exhibits neuroprotective effects in AF64A-treated rats. (-)-Nicotine (0.1 and 0.2 mg/kg, s.c.) was administered once a day for 28 days. On day 14, AF64A (2.5 nmol/side) was injected bilaterally into the hippocampus. Intrahippocampal injection of AF64A showed severe impairment of learning and memory in rats in the water maze and passive avoidance tests. Repeated administration of (-)-nicotine (0.1 and 0.2 mg/kg, s.c.) did not reverse the impairment of memory induced by AF64A in the water maze test. Interestingly, the (-)-nicotine (0.1 and 0.2 mg/kg, s.c.)-treated group showed weak impairment of learning and memory after AF64A treatment compared to the (AF64A + saline)-treated group in the passive avoidance test. These results suggested that (-)-nicotine may have neuroprotective effects against the neurotoxicity induced by AF64A.

  8. Unexpected death of a ventilator-dependent amyotrophic lateral sclerosis patient.

    PubMed

    di Paolo, M; Evangelisti, L; Ambrosino, N

    2013-01-01

    Amyotrophic lateral sclerosis (ALS) is a fatal, progressive, neurodegenerative disease and most patients affected die of respiratory compromise and/or pneumonia within 2-3 years of diagnosis. As ALS progresses, ventilator assistance is required. In the end stages of the disease, patients suffer from respiratory failure and may become ventilator-dependent. Deaths due to malfunction of mechanical ventilators are reported but there are very few forensic autopsy records. We report the case of a 69-year-old ALS female ventilator-dependent, trachostomised patient who was found dead by her husband, with the ventilator in "stand-by" mode. A forensic autopsy was performed. Samples of internal organs were taken for histological and toxicological examination. The ventilator internal memory was also analysed and tested in order to find possible malfunction. Gross examination did not reveal any sign of trauma but showed brain and lung congestion. Pulmonary histological examination revealed thickening of peribronchial interstitial space, alveolar over-distension, break of inter-alveolar walls and diffuse alveolar haemorrhages. Focal microhemorrhages were also detected in other organs. Analysis of the ventilator internal memory showed that during the night of death, there had been several voltage drops. Specific tests revealed malfunction of the internal battery which was unable to provide the necessary voltage, as a consequence the ventilator switched off, stopping ventilation. Battery malfunction reduced the volume of the ventilator alarm, which was not heard by the caregiver. Histological pattern, with acute pulmonary emphysema and focal polivisceral haemorrhages, is strongly suggestive of a death due to "acute" asphyxia. The authors also discuss the need for strict supervision and follow up of these ventilatory dependent patients and their devices. Copyright © 2012 Sociedade Portuguesa de Pneumologia. Published by Elsevier España. All rights reserved.

  9. Association between substandard classroom ventilation rates and students' academic achievement.

    PubMed

    Haverinen-Shaughnessy, U; Moschandreas, D J; Shaughnessy, R J

    2011-04-01

    This study focuses on the relationship between classroom ventilation rates and academic achievement. One hundred elementary schools of two school districts in the southwest United States were included in the study. Ventilation rates were estimated from fifth-grade classrooms (one per school) using CO(2) concentrations measured during occupied school days. In addition, standardized test scores and background data related to students in the classrooms studied were obtained from the districts. Of 100 classrooms, 87 had ventilation rates below recommended guidelines based on ASHRAE Standard 62 as of 2004. There is a linear association between classroom ventilation rates and students' academic achievement within the range of 0.9-7.1 l/s per person. For every unit (1 l/s per person) increase in the ventilation rate within that range, the proportion of students passing standardized test (i.e., scoring satisfactory or above) is expected to increase by 2.9% (95%CI 0.9-4.8%) for math and 2.7% (0.5-4.9%) for reading. The linear relationship observed may level off or change direction with higher ventilation rates, but given the limited number of observations, we were unable to test this hypothesis. A larger sample size is needed for estimating the effect of classroom ventilation rates higher than 7.1 l/s per person on academic achievement. The results of this study suggest that increasing the ventilation rates toward recommended guideline ventilation rates in classrooms should translate into improved academic achievement of students. More studies are needed to fully understand the relationships between ventilation rate, other indoor environmental quality parameters, and their effects on students' health and achievement. Achieving the recommended guidelines and pursuing better understanding of the underlying relationships would ultimately support both sustainable and productive school environments for students and personnel. © 2010 John Wiley & Sons A/S.

  10. 9 CFR 354.226 - Lighting and ventilation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Lighting and ventilation. 354.226 Section 354.226 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Facilities § 354.226 Lighting and ventilation. There shall be ample light, either natural or artificial or...

  11. [Prolonged mechanical ventilation probability model].

    PubMed

    Añón, J M; Gómez-Tello, V; González-Higueras, E; Oñoro, J J; Córcoles, V; Quintana, M; López-Martínez, J; Marina, L; Choperena, G; García-Fernández, A M; Martín-Delgado, C; Gordo, F; Díaz-Alersi, R; Montejo, J C; Lorenzo, A García de; Pérez-Arriaga, M; Madero, R

    2012-10-01

    To design a probability model for prolonged mechanical ventilation (PMV) using variables obtained during the first 24 hours of the start of MV. An observational, prospective, multicenter cohort study. Thirteen Spanish medical-surgical intensive care units. Adult patients requiring mechanical ventilation for more than 24 hours. None. APACHE II, SOFA, demographic data, clinical data, reason for mechanical ventilation, comorbidity, and functional condition. A multivariate risk model was constructed. The model contemplated a dependent variable with three possible conditions: 1. Early mortality; 2. Early extubation; and 3. PMV. Of the 1661 included patients, 67.9% (n=1127) were men. Age: 62.1±16.2 years. APACHE II: 20.3±7.5. Total SOFA: 8.4±3.5. The APACHE II and SOFA scores were higher in patients ventilated for 7 or more days (p=0.04 and p=0.0001, respectively). Noninvasive ventilation failure was related to PMV (p=0.005). A multivariate model for the three above exposed outcomes was generated. The overall accuracy of the model in the training and validation sample was 0.763 (95%IC: 0.729-0.804) and 0.751 (95%IC: 0.672-0.816), respectively. The likelihood ratios (LRs) for early extubation, involving a cutoff point of 0.65, in the training sample were LR (+): 2.37 (95%CI: 1.77-3.19) and LR (-): 0.47 (95%CI: 0.41-0.55). The LRs for the early mortality model, for a cutoff point of 0.73, in the training sample, were LR (+): 2.64 (95%CI: 2.01-3.4) and LR (-): 0.39 (95%CI: 0.30-0.51). The proposed model could be a helpful tool in decision making. However, because of its moderate accuracy, it should be considered as a first approach, and the results should be corroborated by further studies involving larger samples and the use of standardized criteria. Copyright © 2011 Elsevier España, S.L. y SEMICYUC. All rights reserved.

  12. Gas transfer model to design a ventilator for neonatal total liquid ventilation.

    PubMed

    Bonfanti, Mirko; Cammi, Antonio; Bagnoli, Paola

    2015-12-01

    The study was aimed to optimize the gas transfer in an innovative ventilator for neonatal Total Liquid Ventilation (TLV) that integrates the pumping and oxygenation functions in a non-volumetric pulsatile device made of parallel flat silicone membranes. A computational approach was adopted to evaluate oxygen (O2) and carbon dioxide (CO2) exchanges between the liquid perfluorocarbon (PFC) and the oxygenating gas, as a function of the geometrical parameter of the device. A 2D semi-empirical model was implemented to this purpose using Comsol Multiphysics to study both the fluid dynamics and the gas exchange in the ventilator. Experimental gas exchanges measured with a preliminary prototype were compared to the simulation outcomes to prove the model reliability. Different device configurations were modeled to identify the optimal design able to guarantee the desired gas transfer. Good agreement between experimental and simulation outcomes was obtained, validating the model. The optimal configuration, able to achieve the desired gas exchange (ΔpCO2 = 16.5 mmHg and ΔpO2 = 69 mmHg), is a device comprising 40 modules, 300 mm in length (total exchange area = 2.28 m(2)). With this configuration gas transfer performance is satisfactory for all the simulated settings, proving good adaptability of the device. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

  13. Course of Weaning from Prolonged Mechanical Ventilation after Cardiac Surgery

    PubMed Central

    Herlihy, James P.; Koch, Stephen M.; Jackson, Robert; Nora, Hope

    2006-01-01

    In order to determine the temporal pattern of weaning from mechanical ventilation for patients undergoing prolonged mechanical ventilation after cardiac surgery, we performed a retrospective review of 21 patients' weaning courses at our long-term acute care hospital. Using multiple regression analysis of an estimate of individual patients' percentage of mechanical ventilator support per day (%MVSD), we determined that 14 of 21 patients (67%) showed a statistically significant quadratic or cubic relationship between time and %MVSD. These patients showed little or no improvement in their ventilator dependence until a point in time when, abruptly, they began to make rapid progress (a “wean turning point”), after which they progressed to discontinuation of mechanical ventilation in a relatively short period of time. The other 7 patients appeared to have a similar weaning pattern, although the data were not statistically significant. Most patients in the study group weaned from the ventilator through a specific temporal pattern that is newly described herein. Data analysis suggested that the mechanism for the development of a wean turning point was improvement of pulmonary mechanics rather than improvement in gas exchange or respiratory load. Although these observations need to be confirmed by a prospective trial, they may have implications for weaning cardiac surgery patients from prolonged mechanical ventilation, and possibly for weaning a broader group of patients who require prolonged mechanical ventilation. PMID:16878611

  14. Reducing the ingress of urban noise through natural ventilation openings.

    PubMed

    Oldham, D J; de Salis, M H; Sharples, S

    2004-01-01

    For buildings in busy urban areas affected by high levels of road traffic noise the potential to use natural ventilation can be limited by excessive noise entering through ventilation openings. This paper is concerned with techniques to reduce noise ingress into naturally ventilated buildings while minimizing airflow path resistance. A combined experimental and theoretical approach to the interaction of airflow and sound transmission through ventilators for natural ventilation applications is described. A key element of the investigation has been the development of testing facilities capable of measuring the airflow and sound transmission losses for a range of ventilation noise control strategies. It is demonstrated that a combination of sound reduction mechanisms -- one covering low frequency sound and another covering high frequency sound -- is required to attenuate effectively noise from typical urban sources. A method is proposed for quantifying the acoustic performance of different strategies to enable comparisons and informed decisions to be made leading to the possibility of a design methodology for optimizing the ventilation and acoustic performance of different strategies. The need for employing techniques for combating low frequency sound in tandem with techniques for reducing high frequency sound in reducing the ingress of noise from urban sources such as road traffic to acceptable levels is demonstrated. A technique is proposed for enabling the acoustic and airflow performance of apertures for natural ventilation systems to be designed simultaneously.

  15. Pleural liquid and kinetic friction coefficient of mesothelium after mechanical ventilation.

    PubMed

    Bodega, Francesca; Sironi, Chiara; Porta, Cristina; Zocchi, Luciano; Agostoni, Emilio

    2015-01-15

    Volume and protein concentration of pleural liquid in anesthetized rabbits after 1 or 3h of mechanical ventilation, with alveolar pressure equal to atmospheric at end expiration, were compared to those occurring after spontaneous breathing. Moreover, coefficient of kinetic friction between samples of visceral and parietal pleura, obtained after spontaneous or mechanical ventilation, sliding in vitro at physiological velocity under physiological load, was determined. Volume of pleural liquid after mechanical ventilation was similar to that previously found during spontaneous ventilation. This finding is contrary to expectation of Moriondo et al. (2005), based on measurement of lymphatic and interstitial pressure. Protein concentration of pleural liquid after mechanical ventilation was also similar to that occurring after spontaneous ventilation. Coefficient of kinetic friction after mechanical ventilation was 0.023±0.001, similar to that obtained after spontaneous breathing. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. CFD Simulations to Improve Ventilation in Low-Income Housing

    NASA Astrophysics Data System (ADS)

    Ho, Rosemond; Gorle, Catherine

    2017-11-01

    Quality of housing plays an important role in public health. In Dhaka, Bangladesh, the leading causes of death include tuberculosis, lower respiratory infections, and chronic obstructive pulmonary disease, so improving home ventilation could potentially mitigate these negative health effects. The goal of this project is to use computational fluid dynamics (CFD) to predict the relative effectiveness of different ventilation strategies for Dhaka homes. A Reynolds-averaged Navier-Stokes CFD model of a standard Dhaka home with apertures of different sizes and locations was developed to predict air exchange rates. Our initial focus is on simulating ventilation driven by buoyancy-alone conditions, which is often considered the limiting case in natural ventilation design. We explore the relationship between ventilation rate and aperture area to determine the most promising configurations for optimal ventilation solutions. Future research will include the modeling of wind-driven conditions, and extensive uncertainty quantification studies to investigate the effect of variability in the layout of homes and neighborhoods, and in local wind and temperature conditions. The ultimate objective is to formulate robust design recommendations that can reduce risks of respiratory illness in low-income housing.

  17. Microfluidic Pumps Containing Teflon [Trademark] AF Diaphragms

    NASA Technical Reports Server (NTRS)

    Willis, Peter; White, Victor; Grunthaner, Frank; Ikeda, Mike; Mathies, Richard A.

    2009-01-01

    Microfluidic pumps and valves based on pneumatically actuated diaphragms made of Teflon AF polymers are being developed for incorporation into laboratory-on-a-chip devices that must perform well over temperature ranges wider than those of prior diaphragm-based microfluidic pumps and valves. Other potential applications include implanted biomedical microfluidic devices, wherein the biocompatability of Teflon AF polymers would be highly advantageous. These pumps and valves have been demonstrated to function stably after cycling through temperatures from -125 to 120 C. These pumps and valves are intended to be successors to similar prior pumps and valves containing diaphragms made of polydimethylsiloxane (PDMS) [commonly known as silicone rubber]. The PDMS-containing valves ae designed to function stably only within the temperature range from 5 to 80 C. Undesirably, PDMS membranes are somwehat porous and retain water. PDMS is especially unsuitable for use at temperatures below 0 C because the formation of ice crystals increases porosity and introduces microshear.

  18. Open-lung protective ventilation with pressure control ventilation, high-frequency oscillation, and intratracheal pulmonary ventilation results in similar gas exchange, hemodynamics, and lung mechanics.

    PubMed

    Sedeek, Khaled A; Takeuchi, Muneyuki; Suchodolski, Klaudiusz; Vargas, Sara O; Shimaoka, Motomu; Schnitzer, Jay J; Kacmarek, Robert M

    2003-11-01

    Pressure control ventilation (PCV), high-frequency oscillation (HFO), and intratracheal pulmonary ventilation (ITPV) may all be used to provide lung protective ventilation in acute respiratory distress syndrome, but the specific approach that is optimal remains controversial. Saline lavage was used to produce acute respiratory distress syndrome in 21 sheep randomly assigned to receive PCV, HFO, or ITPV as follows: positive end-expiratory pressure (PCV and ITPV) and mean airway pressure (HFO) were set in a pressure-decreasing manner after lung recruitment that achieved a ratio of Pao2/Fio2 > 400 mmHg. Respiratory rates were 30 breaths/min, 120 breaths/min, and 8 Hz, respectively, for PCV, ITPV, and HFO. Eucapnia was targeted with peak carinal pressure of no more than 35 cm H2O. Animals were then ventilated for 4 h. There were no differences among groups in gas exchange, lung mechanics, or hemodynamics. Tidal volume (PCV, 8.9 +/- 2.1 ml/kg; ITPV, 2.7 +/- 0.8 ml/kg; HFO, approximately 2.0 ml/kg) and peak carinal pressure (PCV, 30.6 +/- 2.6 cm H2O; ITPV, 22.3 +/- 4.8 cm H2O; HFO, approximately 24.3 cm H2O) were higher in PCV. Pilot histologic data showed greater interstitial hemorrhage and alveolar septal expansion in PCV than in HFO or ITPV. These data indicate that HFO, ITPV, and PCV when applied with an open-lung protective ventilatory strategy results in the same gas exchange, lung mechanics, and hemodynamic response, but pilot data indicate that lung injury may be greater with PCV.

  19. Feasibility of the capnogram to monitor ventilation rate during cardiopulmonary resuscitation.

    PubMed

    Aramendi, Elisabete; Elola, Andoni; Alonso, Erik; Irusta, Unai; Daya, Mohamud; Russell, James K; Hubner, Pia; Sterz, Fritz

    2017-01-01

    The rates of chest compressions (CCs) and ventilations are both important metrics to monitor the quality of cardiopulmonary resuscitation (CPR). Capnography permits monitoring ventilation, but the CCs provided during CPR corrupt the capnogram and compromise the accuracy of automatic ventilation detectors. The aim of this study was to evaluate the feasibility of an automatic algorithm based on the capnogram to detect ventilations and provide feedback on ventilation rate during CPR, specifically addressing intervals where CCs are delivered. The dataset used to develop and test the algorithm contained in-hospital and out-of-hospital cardiac arrest episodes. The method relies on adaptive thresholding to detect ventilations in the first derivative of the capnogram. The performance of the detector was reported in terms of sensitivity (SE) and Positive Predictive Value (PPV). The overall performance was reported in terms of the rate error and errors in the hyperventilation alarms. Results were given separately for the intervals with CCs. A total of 83 episodes were considered, resulting in 4880min and 46,740 ventilations (8741 during CCs). The method showed an overall SE/PPV above 99% and 97% respectively, even in intervals with CCs. The error for the ventilation rate was below 1.8min -1 in any group, and >99% of the ventilation alarms were correctly detected. A method to provide accurate feedback on ventilation rate using only the capnogram is proposed. Its accuracy was proven even in intervals where canpography signal was severely corrupted by CCs. This algorithm could be integrated into monitor/defibrillators to provide reliable feedback on ventilation rate during CPR. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. Recognition of the 3′ splice site RNA by the U2AF heterodimer involves a dynamic population shift

    PubMed Central

    Voith von Voithenberg, Lena; Sánchez-Rico, Carolina; Kang, Hyun-Seo; Madl, Tobias; Zanier, Katia; Barth, Anders; Warner, Lisa R.; Sattler, Michael; Lamb, Don C.

    2016-01-01

    An essential early step in the assembly of human spliceosomes onto pre-mRNA involves the recognition of regulatory RNA cis elements in the 3′ splice site by the U2 auxiliary factor (U2AF). The large (U2AF65) and small (U2AF35) subunits of the U2AF heterodimer contact the polypyrimidine tract (Py-tract) and the AG-dinucleotide, respectively. The tandem RNA recognition motif domains (RRM1,2) of U2AF65 adopt closed/inactive and open/active conformations in the free form and when bound to bona fide Py-tract RNA ligands. To investigate the molecular mechanism and dynamics of 3′ splice site recognition by U2AF65 and the role of U2AF35 in the U2AF heterodimer, we have combined single-pair FRET and NMR experiments. In the absence of RNA, the RRM1,2 domain arrangement is highly dynamic on a submillisecond time scale, switching between closed and open conformations. The addition of Py-tract RNA ligands with increasing binding affinity (strength) gradually shifts the equilibrium toward an open conformation. Notably, the protein–RNA complex is rigid in the presence of a strong Py-tract but exhibits internal motion with weak Py-tracts. Surprisingly, the presence of U2AF35, whose UHM domain interacts with U2AF65 RRM1, increases the population of the open arrangement of U2AF65 RRM1,2 in the absence and presence of a weak Py-tract. These data indicate that the U2AF heterodimer promotes spliceosome assembly by a dynamic population shift toward the open conformation of U2AF65 to facilitate the recognition of weak Py-tracts at the 3′ splice site. The structure and RNA binding of the heterodimer was unaffected by cancer-linked myelodysplastic syndrome mutants. PMID:27799531

  1. 30 CFR 57.8531 - Construction and maintenance of ventilation doors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Construction and maintenance of ventilation... NONMETAL MINES Ventilation Underground Only § 57.8531 Construction and maintenance of ventilation doors... constructed of wood; (c) Maintained in good condition; (d) Self-closing, if manually operated; and (e...

  2. AT1 receptor blocker losartan protects against mechanical ventilation-induced diaphragmatic dysfunction

    PubMed Central

    Kwon, Oh Sung; Smuder, Ashley J.; Wiggs, Michael P.; Hall, Stephanie E.; Sollanek, Kurt J.; Morton, Aaron B.; Talbert, Erin E.; Toklu, Hale Z.; Tumer, Nihal

    2015-01-01

    Mechanical ventilation is a life-saving intervention for patients in respiratory failure. Unfortunately, prolonged ventilator support results in diaphragmatic atrophy and contractile dysfunction leading to diaphragm weakness, which is predicted to contribute to problems in weaning patients from the ventilator. While it is established that ventilator-induced oxidative stress is required for the development of ventilator-induced diaphragm weakness, the signaling pathway(s) that trigger oxidant production remain unknown. However, recent evidence reveals that increased plasma levels of angiotensin II (ANG II) result in oxidative stress and atrophy in limb skeletal muscles. Using a well-established animal model of mechanical ventilation, we tested the hypothesis that increased circulating levels of ANG II are required for both ventilator-induced diaphragmatic oxidative stress and diaphragm weakness. Cause and effect was determined by administering an angiotensin-converting enzyme inhibitor (enalapril) to prevent ventilator-induced increases in plasma ANG II levels, and the ANG II type 1 receptor antagonist (losartan) was provided to prevent the activation of ANG II type 1 receptors. Enalapril prevented the increase in plasma ANG II levels but did not protect against ventilator-induced diaphragmatic oxidative stress or diaphragm weakness. In contrast, losartan attenuated both ventilator-induced oxidative stress and diaphragm weakness. These findings indicate that circulating ANG II is not essential for the development of ventilator-induced diaphragm weakness but that activation of ANG II type 1 receptors appears to be a requirement for ventilator-induced diaphragm weakness. Importantly, these experiments provide the first evidence that the Food and Drug Administration-approved drug losartan may have clinical benefits to protect against ventilator-induced diaphragm weakness in humans. PMID:26359481

  3. Identification and Characterization of an Antifungal Protein, AfAFPR9, Produced by Marine-Derived Aspergillus fumigatus R9.

    PubMed

    Rao, Qi; Guo, Wenbin; Chen, Xinhua

    2015-05-01

    A fungal strain, R9, was isolated from the South Atlantic sediment sample and identified as Aspergillus fumigatus. An antifungal protein, AfAFPR9, was purified from the culture supernatant of Aspergillus fumigatus R9. AfAFPR9 was identified to be restrictocin, which is a member of the ribosome-inactivating proteins (RIPs), by MALDI-TOF-TOF-MS. AfAFPR9 displayed antifungal activity against plant pathogenic Fusarium oxysporum, Alternaria longipes, Colletotrichum gloeosporioides, Paecilomyces variotii, and Trichoderma viride at minimum inhibitory concentrations of 0.6, 0.6, 1.2, 1.2, and 2.4 μg/disc, respectively. Moreover, AfAFPR9 exhibited a certain extent of thermostability, and metal ion and denaturant tolerance. The iodoacetamide assay showed that the disulfide bridge in AfAFPR9 was indispensable for its antifungal action. The cDNA encoding for AfAFPR9 was cloned from A. fumigatus R9 by RTPCR and heterologously expressed in E. coli. The recombinant AfAFPR9 protein exhibited obvious antifungal activity against C. gloeosporioides, T. viride, and A. longipes. These results reveal the antifungal properties of a RIP member (AfAFPR9) from marine-derived Aspergillus fumigatus and indicated its potential application in controlling plant pathogenic fungi.

  4. 46 CFR 153.314 - Ventilation of spaces not usually occupied.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Ventilation of spaces not usually occupied. 153.314... CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Handling Space Ventilation § 153.314 Ventilation of spaces not usually occupied. (a) Each...

  5. 46 CFR 153.314 - Ventilation of spaces not usually occupied.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Ventilation of spaces not usually occupied. 153.314... CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Handling Space Ventilation § 153.314 Ventilation of spaces not usually occupied. (a) Each...

  6. 46 CFR 153.314 - Ventilation of spaces not usually occupied.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Ventilation of spaces not usually occupied. 153.314... CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Handling Space Ventilation § 153.314 Ventilation of spaces not usually occupied. (a) Each...

  7. 46 CFR 153.314 - Ventilation of spaces not usually occupied.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Ventilation of spaces not usually occupied. 153.314... CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Handling Space Ventilation § 153.314 Ventilation of spaces not usually occupied. (a) Each...

  8. 46 CFR 153.314 - Ventilation of spaces not usually occupied.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Ventilation of spaces not usually occupied. 153.314... CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Handling Space Ventilation § 153.314 Ventilation of spaces not usually occupied. (a) Each...

  9. Higher risk of death and stroke in patients with persistent vs. paroxysmal atrial fibrillation: results from the ROCKET-AF Trial.

    PubMed

    Steinberg, Benjamin A; Hellkamp, Anne S; Lokhnygina, Yuliya; Patel, Manesh R; Breithardt, Günter; Hankey, Graeme J; Becker, Richard C; Singer, Daniel E; Halperin, Jonathan L; Hacke, Werner; Nessel, Christopher C; Berkowitz, Scott D; Mahaffey, Kenneth W; Fox, Keith A A; Califf, Robert M; Piccini, Jonathan P

    2015-02-01

    Anticoagulation prophylaxis for stroke is recommended for at-risk patients with either persistent or paroxysmal atrial fibrillation (AF). We compared outcomes in patients with persistent vs. paroxysmal AF receiving oral anticoagulation. Patients randomized in the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET-AF) trial (n = 14 264) were grouped by baseline AF category: paroxysmal or persistent. Multivariable adjustment was performed to compare thrombo-embolic events, bleeding, and death between groups, in high-risk subgroups, and across treatment assignment (rivaroxaban or warfarin). Of 14 062 patients, 11 548 (82%) had persistent AF and 2514 (18%) had paroxysmal AF. Patients with persistent AF were marginally older (73 vs. 72, P = 0.03), less likely female (39 vs. 45%, P < 0.0001), and more likely to have previously used vitamin K antagonists (64 vs. 56%, P < 0.0001) compared with patients with paroxysmal AF. In patients randomized to warfarin, time in therapeutic range was similar (58 vs. 57%, P = 0.94). Patients with persistent AF had higher adjusted rates of stroke or systemic embolism (2.18 vs. 1.73 events per 100-patient-years, P = 0.048) and all-cause mortality (4.78 vs. 3.52, P = 0.006). Rates of major bleeding were similar (3.55 vs. 3.31, P = 0.77). Rates of stroke or systemic embolism in both types of AF did not differ by treatment assignment (rivaroxaban vs. warfarin, Pinteraction = 0.6). In patients with AF at moderate-to-high risk of stroke receiving anticoagulation, those with persistent AF have a higher risk of thrombo-embolic events and worse survival compared with paroxysmal AF. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Cardiology.

  10. Higher risk of death and stroke in patients with persistent vs. paroxysmal atrial fibrillation: results from the ROCKET-AF Trial

    PubMed Central

    Steinberg, Benjamin A.; Hellkamp, Anne S.; Lokhnygina, Yuliya; Patel, Manesh R.; Breithardt, Günter; Hankey, Graeme J.; Becker, Richard C.; Singer, Daniel E.; Halperin, Jonathan L.; Hacke, Werner; Nessel, Christopher C.; Berkowitz, Scott D.; Mahaffey, Kenneth W.; Fox, Keith A.A.; Califf, Robert M.; Piccini, Jonathan P.

    2015-01-01

    Aim Anticoagulation prophylaxis for stroke is recommended for at-risk patients with either persistent or paroxysmal atrial fibrillation (AF). We compared outcomes in patients with persistent vs. paroxysmal AF receiving oral anticoagulation. Methods and results Patients randomized in the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET-AF) trial (n = 14 264) were grouped by baseline AF category: paroxysmal or persistent. Multivariable adjustment was performed to compare thrombo-embolic events, bleeding, and death between groups, in high-risk subgroups, and across treatment assignment (rivaroxaban or warfarin). Of 14 062 patients, 11 548 (82%) had persistent AF and 2514 (18%) had paroxysmal AF. Patients with persistent AF were marginally older (73 vs. 72, P = 0.03), less likely female (39 vs. 45%, P < 0.0001), and more likely to have previously used vitamin K antagonists (64 vs. 56%, P < 0.0001) compared with patients with paroxysmal AF. In patients randomized to warfarin, time in therapeutic range was similar (58 vs. 57%, P = 0.94). Patients with persistent AF had higher adjusted rates of stroke or systemic embolism (2.18 vs. 1.73 events per 100-patient-years, P = 0.048) and all-cause mortality (4.78 vs. 3.52, P = 0.006). Rates of major bleeding were similar (3.55 vs. 3.31, P = 0.77). Rates of stroke or systemic embolism in both types of AF did not differ by treatment assignment (rivaroxaban vs. warfarin, Pinteraction = 0.6). Conclusion In patients with AF at moderate-to-high risk of stroke receiving anticoagulation, those with persistent AF have a higher risk of thrombo-embolic events and worse survival compared with paroxysmal AF. PMID:25209598

  11. Influence of gestational age on dead space and alveolar ventilation in preterm infants ventilated with volume guarantee.

    PubMed

    Neumann, Roland P; Pillow, Jane J; Thamrin, Cindy; Larcombe, Alexander N; Hall, Graham L; Schulzke, Sven M

    2015-01-01

    Ventilated preterm infant lungs are vulnerable to overdistension and underinflation. The optimal ventilator-delivered tidal volume (VT) in these infants is unknown and may depend on the extent of alveolarisation at birth. We aimed to calculate respiratory dead space (VD) from the molar mass (MM) signal of an ultrasonic flowmeter (VD,MM) in very preterm infants on volume-targeted ventilation (VT target, 4-5 ml/kg) and to study the association between gestational age (GA) and VD,MM-to-VT ratio (VD,MM/VT), alveolar tidal volume (VA) and alveolar minute volume (AMV). This was a single-centre, prospective, observational, cohort study in a neonatal intensive care unit. Tidal breathing analysis was performed in ventilated very preterm infants (GA range 23-32 weeks) on day 1 of life. Valid measurements were obtained in 43/51 (87%) infants. Tidal breathing variables were analysed using multivariable linear regression. VD,MM/VT was negatively associated with GA after adjusting for birth weight Z score (p < 0.001, R(2) = 0.26). This association was primarily influenced by the appliance dead space. Despite similar VT/kg and VA/kg across all studied infants, respiratory rate and AMV/kg increased with GA. VD,app rather than anatomical VD is the major factor influencing increased VD,MM/VT at a younger GA. A volume guarantee setting of 4-5 ml/kg in the Dräger Babylog® 8000 plus ventilator may be inappropriate as a universal target across the GA range of 23-32 weeks. Differences between measured and set VT and the dependence of this difference on GA require further investigation. © 2014 S. Karger AG, Basel.

  12. Mechanical ventilation interacts with endotoxemia to induce extrapulmonary organ dysfunction

    PubMed Central

    O'Mahony, D Shane; Liles, W Conrad; Altemeier, William A; Dhanireddy, Shireesha; Frevert, Charles W; Liggitt, Denny; Martin, Thomas R; Matute-Bello, Gustavo

    2006-01-01

    Introduction Multiple organ dysfunction syndrome (MODS) is a common complication of sepsis in mechanically ventilated patients with acute respiratory distress syndrome, but the links between mechanical ventilation and MODS are unclear. Our goal was to determine whether a minimally injurious mechanical ventilation strategy synergizes with low-dose endotoxemia to induce the activation of pro-inflammatory pathways in the lungs and in the systemic circulation, resulting in distal organ dysfunction and/or injury. Methods We administered intraperitoneal Escherichia coli lipopolysaccharide (LPS; 1 μg/g) to C57BL/6 mice, and 14 hours later subjected the mice to 6 hours of mechanical ventilation with tidal volumes of 10 ml/kg (LPS + MV). Comparison groups received ventilation but no LPS (MV), LPS but no ventilation (LPS), or neither LPS nor ventilation (phosphate-buffered saline; PBS). Results Myeloperoxidase activity and the concentrations of the chemokines macrophage inflammatory protein-2 (MIP-2) and KC were significantly increased in the lungs of mice in the LPS + MV group, in comparison with mice in the PBS group. Interestingly, permeability changes across the alveolar epithelium and histological changes suggestive of lung injury were minimal in mice in the LPS + MV group. However, despite the minimal lung injury, the combination of mechanical ventilation and LPS resulted in chemical and histological evidence of liver and kidney injury, and this was associated with increases in the plasma concentrations of KC, MIP-2, IL-6, and TNF-α. Conclusion Non-injurious mechanical ventilation strategies interact with endotoxemia in mice to enhance pro-inflammatory mechanisms in the lungs and promote extra-pulmonary end-organ injury, even in the absence of demonstrable acute lung injury. PMID:16995930

  13. Multicenter comparative study of conventional mechanical gas ventilation to tidal liquid ventilation in oleic acid injured sheep.

    PubMed

    Wolfson, Marla R; Hirschl, Ronald B; Jackson, J Craig; Gauvin, France; Foley, David S; Lamm, Wayne J E; Gaughan, John; Shaffer, Thomas H

    2008-01-01

    We performed a multicenter study to test the hypothesis that tidal liquid ventilation (TLV) would improve cardiopulmonary, lung histomorphological, and inflammatory profiles compared with conventional mechanical gas ventilation (CMV). Sheep were studied using the same volume-controlled, pressure-limited ventilator systems, protocols, and treatment strategies in three independent laboratories. Following baseline measurements, oleic acid lung injury was induced and animals were randomized to 4 hours of CMV or TLV targeted to "best PaO2" and PaCO2 35 to 60 mm Hg. The following were significantly higher (p < 0.01) during TLV than CMV: PaO2, venous oxygen saturation, respiratory compliance, cardiac output, stroke volume, oxygen delivery, ventilatory efficiency index; alveolar area, lung % gas exchange space, and expansion index. The following were lower (p < 0.01) during TLV compared with CMV: inspiratory and expiratory pause pressures, mean airway pressure, minute ventilation, physiologic shunt, plasma lactate, lung interleukin-6, interleukin-8, myeloperoxidase, and composite total injury score. No significant laboratories by treatment group interactions were found. In summary, TLV resulted in improved cardiopulmonary physiology at lower ventilatory requirements with more favorable histological and inflammatory profiles than CMV. As such, TLV offers a feasible ventilatory alternative as a lung protective strategy in this model of acute lung injury.

  14. [Alveolar ventilation and recruitment under lung protective ventilation].

    PubMed

    Putensen, Christian; Muders, Thomas; Kreyer, Stefan; Wrigge, Hermann

    2008-11-01

    Goal of mechanical ventilation is to improve gas exchange and reduce work of breathing without contributing to further lung injury. Besides providing adequate EELV and thereby arterial oxygenation PEEP in addition to a reduction in tidal volume is required to prevent cyclic alveolar collapse and tidal recruitment and hence protective mechanical ventilation. Currently, there is no consensus if and if yes at which price alveolar recruitment with high airway pressures should be intended ("open up the lung"), or if it is more important to reduce the mechanical stress and strain to the lungs as much as possible ("keep the lung closed"). Potential of alveolar recruitment differs from patient to patient but also between lung regions. Potential for recruitment depends probably more on regional lung mechanics - especially on lung elastance - than on the underlying disease. Based on available data neither high PEEP nor other methods used for alveolar recruitment could demonstrate a survival benefit in patients with ARDS. These results may support an individualized titration of PEEP or other manoeuvres used for recruitment taking into consideration the regional effects. Bedside imaging techniques allowing titration of PEEP or other manoeuvres to prevent end-expiratory alveolar collapse (tidal recruitment) and inspiratory overinflation may be a promising development.

  15. [Implementation of modern trends in the methods of the ventilation support in the new apparatus for artificial lung ventilation Avenir-221 P].

    PubMed

    Gal'perin, Iu Sh; Alkhimova, L R; Dmitriev, N D; Kozlova, I A; Nemirovskiĭ, S B; Makarov, M V; Safronov, A Iu

    2005-01-01

    In the new ventilator Avenir-221 P modern lines of development of ventilation support in intensive therapy of adults and children are implemented. The capacities of the ventilator are successfully combined with its technical decisions which include microprocessor parametrical controlling, programming-controlled electric drive, an information saturation, intuitively clear control system, protection against interruption of power supply sources and oxygen feeding falls. A set of functional characteristics (modes VCV, PCV, Ass/Contr, PSV, SIMV, PEEP, Sigh, etc.) in combination with an original design make the device the most accessible and promising for application in intensive care and resuscitation units of a wide network of Russian hospitals and clinics. The ventilator Avenir-221 P has passed all required tests and is presently commercially available.

  16. Home Mechanical Ventilation: A 12-Year Population-Based Retrospective Cohort Study.

    PubMed

    Povitz, Marcus; Rose, Louise; Shariff, Salimah Z; Leonard, Sean; Welk, Blayne; Jenkyn, Krista Bray; Leasa, David J; Gershon, Andrea S

    2018-04-01

    Increasing numbers of individuals are being initiated on home mechanical ventilation, including noninvasive (bi-level) and invasive mechanical ventilation delivered via tracheostomy due to chronic respiratory failure to enable symptom management and promote quality of life. Given the high care needs of these individuals, a better understanding of the indications for home mechanical ventilation, and health-care utilization is needed. We performed a retrospective cohort study using provincial health administrative data from Ontario, Canada (population ∼13,000,000). Home mechanical ventilation users were characterized using health administrative data to determine the indications for home mechanical ventilation, the need for acute care at the time of ventilation approval, and their health service use and mortality rates following approval. The annual incidence of home mechanical ventilation approval rose from 1.8/100,000 in 2000 to 5.0/100,000 in 2012, or an annual increase of approximately 0.3/100,000 persons/y. The leading indications were neuromuscular disease, thoracic restriction, and COPD. The indication for the remainder could not be determined due to limitations of the administrative databases. Of the 4,670 individuals, 23.0% commenced home mechanical ventilation following an acute care hospitalization. Among individuals who survived at least 1 y, fewer required hospitalization in the year that followed home mechanical ventilation approval (29.9% vs 39.8%) as compared with the year prior. Utilization of home mechanical ventilation is increasing in Ontario, Canada, and further study is needed to clarify the factors contributing to this and to further optimize utilization of health-care resources. Copyright © 2018 by Daedalus Enterprises.

  17. Amyotrophic lateral sclerosis and assisted ventilation: how patients decide.

    PubMed

    Lemoignan, Josée; Ells, Carolyn

    2010-06-01

    Throughout the course of their illness, people with amyotrophic lateral sclerosis (ALS) must make many treatment decisions; however, none has such a significant impact on quality of life and survival as decisions about assisted ventilation. The purpose of this study was to better understand the experience of decision-making about assisted ventilation for ALS patients. Using qualitative phenomenology methodology, 10 semi-structured interviews were conducted with persons with ALS and their caregivers to elicit factors that are pertinent to their decision-making process about assisted ventilation. Six main themes emerged from the interviews. (1) the meaning of the intervention - participants made a sharp distinction between non-invasive ventilation, which they viewed as a means to relieve symptoms of respiratory failure, and invasive ventilation, which they viewed as taking over their breathing and thereby saving their life when they otherwise would die, (2) the importance of context - including functional status, available supports, and financial implications, (3) the importance of values - with respect to communication, relationships, autonomy, life, and quality of life, (4) the effect of fears - particularly respiratory distress, chocking, running out of air, and the process of death itself, (5) the need for information - how use of assisted ventilation would impact daily life, how death from respiratory failure would occur, how caregivers and persons with ALS differ in their information needs and common misconceptions, and (6) adaptation to or acceptance of the intervention - a lengthy process that involved gradual familiarization with the equipment and its benefits. People with ALS and caregivers value autonomy in decision-making about assisted ventilation. Their decision-making process is neither wholly rational nor self-interested, and includes factors that health professionals should anticipate and address. Discussions about assisted ventilation and timing

  18. Activation function 2 (AF2) of estrogen receptor-α is required for the atheroprotective action of estradiol but not to accelerate endothelial healing

    PubMed Central

    Billon-Galés, Audrey; Krust, Andrée; Fontaine, Coralie; Abot, Anne; Flouriot, Gilles; Toutain, Céline; Berges, Hortense; Gadeau, Alain-Pierre; Lenfant, Françoise; Gourdy, Pierre; Chambon, Pierre; Arnal, Jean-François

    2011-01-01

    17β-Estradiol (E2) regulates estrogen receptor-α (ERα) target gene transcription through the two independent activation functions (AFs), AF1 and AF2, located in the N-terminal and ligand binding domain of ERα, respectively. We previously reported that ERα is required for the E2 atheroprotective action as well as for its accelerative action on endothelial healing, but its AF1 function is dispensable. Here, we investigated the role of ERαAF2 in these two major beneficial actions of E2 by electively targeting ERαAF2 (named ERαAF20). Our results prove four points. (i) Compared with WT ERα, the ability of ERαAF20 to stimulate the C3 complement or the estrogen response element-thymidine kinase promoter in two cell lines was dramatically decreased, confirming the importance of AF2 in the E2-induced transcriptional activity of ERα. (ii) The uterotrophic action of E2 was totally absent in ERαAF20 mice, showing the crucial role of ERαAF2 in E2-induced uterus hyperplasia. (iii) ERαAF2 was dispensable for the accelerative action of E2 on endothelial healing, underlining the functionality of ERαAF20 in vivo. (iv) Finally, the atheroprotective effect of E2 was abrogated in ERαAF20 LDL-r−/− mice. Thus, whereas ERαAF1 and ERαAF2 are both required for the uterotrophic action of E2, we show that only ERαAF2 is necessary for its atheroprotective effect. PMID:21788522

  19. Minute ventilation of cyclists, car and bus passengers: an experimental study.

    PubMed

    Zuurbier, Moniek; Hoek, Gerard; van den Hazel, Peter; Brunekreef, Bert

    2009-10-27

    Differences in minute ventilation between cyclists, pedestrians and other commuters influence inhaled doses of air pollution. This study estimates minute ventilation of cyclists, car and bus passengers, as part of a study on health effects of commuters' exposure to air pollutants. Thirty-four participants performed a submaximal test on a bicycle ergometer, during which heart rate and minute ventilation were measured simultaneously at increasing cycling intensity. Individual regression equations were calculated between heart rate and the natural log of minute ventilation. Heart rates were recorded during 280 two hour trips by bicycle, bus and car and were calculated into minute ventilation levels using the individual regression coefficients. Minute ventilation during bicycle rides were on average 2.1 times higher than in the car (individual range from 1.3 to 5.3) and 2.0 times higher than in the bus (individual range from 1.3 to 5.1). The ratio of minute ventilation of cycling compared to travelling by bus or car was higher in women than in men. Substantial differences in regression equations were found between individuals. The use of individual regression equations instead of average regression equations resulted in substantially better predictions of individual minute ventilations. The comparability of the gender-specific overall regression equations linking heart rate and minute ventilation with one previous American study, supports that for studies on the group level overall equations can be used. For estimating individual doses, the use of individual regression coefficients provides more precise data. Minute ventilation levels of cyclists are on average two times higher than of bus and car passengers, consistent with the ratio found in one small previous study of young adults. The study illustrates the importance of inclusion of minute ventilation data in comparing air pollution doses between different modes of transport.

  20. Measuring Teachers' Assessment for Learning (AfL) Classroom Practices in Elementary Schools

    ERIC Educational Resources Information Center

    Lysaght, Zita; O'Leary, Michael; Ludlow, Larry

    2017-01-01

    Assessment for Learning (AfL) may be conceptualized as minute-to-minute, day-by-day interactions between learners and teachers with the improvement of learning as the principal focus. This paper traces the development of an AfL measurement instrument (scale) that can be used for research purposes prior to, during and following professional…