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https://www.readbyqxmd.com/read/28828372/high-flow-nasal-oxygen-therapy-and-noninvasive-ventilation-in-the-management-of-acute-hypoxemic-respiratory-failure
#1
REVIEW
Jean-Pierre Frat, Rémi Coudroy, Nicolas Marjanovic, Arnaud W Thille
High-flow nasal cannula (HFNC) oxygen therapy is a recent technique delivering a high flow of heated and humidified gas. HFNC is simpler to use and apply than noninvasive ventilation (NIV) and appears to be a good alternative treatment for hypoxemic acute respiratory failure (ARF). HFNC is better tolerated than NIV, delivers high fraction of inspired oxygen (FiO2), generates a low level of positive pressure and provides washout of dead space in the upper airways, thereby improving mechanical pulmonary properties and unloading inspiratory muscles during ARF...
July 2017: Annals of Translational Medicine
https://www.readbyqxmd.com/read/28794144/nasal-high-flow-therapy-a-novel-treatment-rather-than-a-more-expensive-oxygen-device
#2
REVIEW
Eleni Ischaki, Ioannis Pantazopoulos, Spyros Zakynthinos
Nasal high flow is a promising novel oxygen delivery device, whose mechanisms of action offer some beneficial effects over conventional oxygen systems. The administration of a high flow of heated and humidified gas mixture promotes higher and more stable inspiratory oxygen fraction values, decreases anatomical dead space and generates a positive airway pressure that can reduce the work of breathing and enhance patient comfort and tolerance. Nasal high flow has been used as a prophylactic tool or as a treatment device mostly in patients with acute hypoxaemic respiratory failure, with the majority of studies showing positive results...
September 30, 2017: European Respiratory Review: An Official Journal of the European Respiratory Society
https://www.readbyqxmd.com/read/28756120/comparison-of-two-strategies-for-ex-vivo-lung-perfusion
#3
Tobias Nilsson, Jan F Gielis, Alexis Slama, Christoffer Hansson, Andreas Wallinder, Sven-Erik Ricksten, Göran Dellgren
BACKGROUND: Two clinically used strategies for ex vivo lung perfusion (EVLP) were compared in a porcine model with respect to lung function, metabolism, inflammatory response, oxidative stress, and cell viability. METHODS: Porcine lungs (n = 20) were preserved, harvested, and kept cooled for 2 hours. After randomization, EVLP was performed using a cellular perfusate and open left atrium (COA group) or an acellular perfusate and a closed left atrium (ACA group). Oxygenation (partial pressure of arterial oxygen/fraction of inspired oxygen), compliance, dead space, weight, and perfusate oncotic pressure were registered before and after a 4-hour period of reconditioning...
July 8, 2017: Journal of Heart and Lung Transplantation
https://www.readbyqxmd.com/read/28666570/dead-space-ventilation-is-linked-to-exercise-capacity-and-survival-in-distal-chronic-thromboembolic-pulmonary-hypertension
#4
Laurent Godinas, Caroline Sattler, Edmund M Lau, Xavier Jaïs, Yu Taniguchi, Mitja Jevnikar, Jason Weatherald, Olivier Sitbon, Laurent Savale, David Montani, Gérald Simonneau, Marc Humbert, Pierantonio Laveneziana, Gilles Garcia
BACKGROUND: Cardiopulmonary exercise testing (CPET) is frequently used for the evaluation of patients with pulmonary hypertension (PH). Non-operable distal chronic thromboembolic pulmonary hypertension (CTEPH) represents a unique subgroup of PH where microvascular disease resembling pulmonary arterial hypertension (PAH) may predominate and efficacious medical therapy is now available. However, little is known regarding the detailed CPET profile of patients with distal CTEPH, and whether ventilation and gas exchange responses are different from PAH...
May 22, 2017: Journal of Heart and Lung Transplantation
https://www.readbyqxmd.com/read/28665692/excess-ventilation-in-copd-heart-failure-overlap-implications-for-dyspnea-and-exercise-intolerance
#5
Alcides Rocha, Flavio F Arbex, Priscilla A Sperandio, Aline Souza, Ligia Biazzim, Frederico Mancuso, Danilo C Berton, Bruno Hochhegger, Maria Clara N Alencar, Luiz E Nery, Denis E O'Donnell, J Alberto Neder
BACKGROUND: An increased ventilatory response to exertional metabolic demand (high ventilation (⩒E)-carbon dioxide output (⩒CO2) relationship) is a common finding in patients with coexistent COPD-heart failure. We aimed to determine the mechanisms underlying high ⩒E-⩒CO2 and its impact on operating lung volumes, dyspnea and exercise tolerance in these patients. METHODS: Twenty-two ex-smokers with combined COPD and heart failure with reduced left ventricular ejection fraction (LVEF) undertook, after careful treatment optimization, a progressive cycle exercise test with capillary (c) blood gas collection...
June 30, 2017: American Journal of Respiratory and Critical Care Medicine
https://www.readbyqxmd.com/read/28611227/lung-injury-etiology-and-other-factors-influencing-the-relationship-between-dead-space-fraction-and-mortality-in-ards
#6
Richard H Kallet, Hanjing Zhuo, Kelly Ho, Michael S Lipnick, Antonio Gomez, Michael A Matthay
BACKGROUND: In ARDS, elevated pulmonary dead-space fraction (VD/VT) is a particularly strong indicator of mortality risk. Whether the magnitude of VD/VT is modified by the underlying etiology of ARDS and whether this influences the strength of its association with mortality remains unknown. We sought to elucidate the impact of ARDS etiology on VD/VT and also to determine whether ARDS severity, as classified by the Berlin definition, has correspondence with changes in VD/VT. METHODS: This single-center, retrospective, observational study (2010-2016) measured VD/VT in 685 subjects with ARDS as part of clinical management with lung-protective ventilation...
June 13, 2017: Respiratory Care
https://www.readbyqxmd.com/read/28599888/cardiopulmonary-effects-of-pleural-insufflation-with-co2-during-two-lung-ventilation-in-dorsally-recumbent-anesthetized-horses
#7
Kaylee S Bohaychuk-Preuss, M Valentina Carrozzo, Tanya Duke-Novakovski
OBJECTIVE: To record the cardiopulmonary effects of pleural CO2 positive pressure insufflation in anesthetized horses. STUDY DESIGN: Prospective study. ANIMALS: Seven horses (mean ± standard deviation, 530.9 ± 68.1 kg) undergoing terminal surgery. METHODS: Horses were sedated with xylazine. Anesthesia was induced with ketamine-propofol and maintained with isoflurane, positive pressure ventilation, detomidine infusion, and butorphanol with the horses in dorsal recumbency...
January 10, 2017: Veterinary Anaesthesia and Analgesia
https://www.readbyqxmd.com/read/28596273/novel-analysis-of-4dct-imaging-quantifies-progressive-increases-in-anatomic-dead-space-during-mechanical-ventilation-in-mice
#8
Elizabeth H Kim, Melissa Preissner, Richard P Carnibella, Chaminda R Samarage, Ellen Bennett, Marcio A Diniz, Andreas Fouras, Graeme R Zosky, Heather D Jones
Increased dead space is an important prognostic marker in early acute respiratory distress syndrome (ARDS) that correlates with mortality. The cause of increased dead space in ARDS has largely been attributed to increased alveolar dead space due to ventilation/perfusion mismatching and shunt. We sought to determine whether anatomic dead space also increases in response to mechanical ventilation. Mice received intratracheal lipopolysaccharide (LPS) or saline and mechanical ventilation (MV). Four-dimensional computed tomography (4DCT) scans were performed at onset of MV and after 5 h of MV...
September 1, 2017: Journal of Applied Physiology
https://www.readbyqxmd.com/read/28578708/effects-of-neurally-adjusted-ventilatory-assist-on-air-distribution-and-dead-space-in-patients-with-acute-exacerbation-of-chronic-obstructive-pulmonary-disease
#9
Qin Sun, Ling Liu, Chun Pan, Zhanqi Zhao, Jingyuan Xu, Airan Liu, Haibo Qiu
BACKGROUND: Neurally adjusted ventilatory assist (NAVA) could improve patient-ventilator interaction; its effects on ventilation distribution and dead space are still unknown. The aim of this study was to evaluate the effects of varying levels of assist during NAVA and pressure support ventilation (PSV) on ventilation distribution and dead space in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). METHODS: Fifteen mechanically ventilated patients with AECOPD were included in the study...
June 2, 2017: Critical Care: the Official Journal of the Critical Care Forum
https://www.readbyqxmd.com/read/28475040/model-based-estimation-of-respiratory-parameters-from-capnography-with-application-to-diagnosing-obstructive-lung-disease
#10
Abubakar Abid, Rebecca J Mieloszyk, George C Verghese, Baruch S Krauss, Thomas Heldt
OBJECTIVE: We use a single-alveolar-compartment model to describe the partial pressure of carbon dioxide in exhaled breath, as recorded in time-based capnography. Respiratory parameters are estimated using this model and then related to the clinical status of patients with obstructive lung disease. METHODS: Given appropriate assumptions, we derive an analytical solution of the model, describing the exhalation segment of the capnogram. This solution is parametrized by alveolar CO2 concentration, dead-space fraction, and the time constant associated with exhalation...
May 2, 2017: IEEE Transactions on Bio-medical Engineering
https://www.readbyqxmd.com/read/28427718/improved-linear-quadratic-and-proportional-control-system-for-improved-liquid-level-system-regulation-in-a-coke-fractionation-tower
#11
Jili Tao, Qinru Fan, Longhua Ma
A new linear quadratic regulation (LQ) control plus a proportional (P) control system is proposed for the level regulation in an industrial coke fractionation tower. The process is first stabilized using a P controller and then a subsequent LQ controller is designed for the P control system. The P control system is modeled as a generalized first order plus dead time (FOPDT) process using step-response test and the LQ-P controller is designed through a new state space structure. Performance in terms of regulatory and servo issues were investigated...
April 17, 2017: ISA Transactions
https://www.readbyqxmd.com/read/28413511/application-of-dead-space-fraction-to-titrate-optimal-positive-end-expiratory-pressure-in-an-ards-swine-model
#12
Weishuai Bian, Wei Chen, Yangong Chao, Lan Wang, Liming Li, Jian Guan, Xuefeng Zang, Jie Zhen, Bo Sheng, Xi Zhu
This study aimed to apply the dead space fraction [ratio of dead space to tidal volume (VD/VT)] to titrate the optimal positive end-expiratory pressure (PEEP) in a swine model of acute respiratory distress syndrome (ARDS). Twelve swine models of ARDS were constructed. A lung recruitment maneuver was then conducted and the PEEP was set at 20 cm H2O. The PEEP was reduced by 2 cm H2O every 10 min until 0 cm H2O was reached, and VD/VT was measured after each decrement step. VD/VT was measured using single-breath analysis of CO2, and calculated from arterial CO2 partial pressure (PaCO2) and mixed expired CO2 (PeCO2) using the following formula: VD/VT = (PaCO2 - PeCO2)/PaCO2...
April 2017: Experimental and Therapeutic Medicine
https://www.readbyqxmd.com/read/28372575/implementing-a-bedside-assessment-of-respiratory-mechanics-in-patients-with-acute-respiratory-distress-syndrome
#13
Lu Chen, Guang-Qiang Chen, Kevin Shore, Orest Shklar, Concetta Martins, Brian Devenyi, Paul Lindsay, Heather McPhail, Ashley Lanys, Ibrahim Soliman, Mazin Tuma, Michael Kim, Kerri Porretta, Pamela Greco, Hilary Every, Chris Hayes, Andrew Baker, Jan O Friedrich, Laurent Brochard
BACKGROUND: Despite their potential interest for clinical management, measurements of respiratory mechanics in patients with acute respiratory distress syndrome (ARDS) are seldom performed in routine practice. We introduced a systematic assessment of respiratory mechanics in our clinical practice. After the first year of clinical use, we retrospectively assessed whether these measurements had any influence on clinical management and physiological parameters associated with clinical outcomes by comparing their value before and after performing the test...
April 4, 2017: Critical Care: the Official Journal of the Critical Care Forum
https://www.readbyqxmd.com/read/28351440/-high-nasal-flow-the-solution-for-hypoxaemia
#14
J G van den Aardweg
High nasal flow (HNF) is a new method to deliver a high flow of oxygen (up to 60 l/min) through a nasal cannula. The inspiratory oxygen fraction can be set in a range from 21 to 100%. The inspired air is adjusted to body temperature and saturation. Many patients find it more comfortable than a conventional oxygen mask. In spite of these advantages, the mechanism of action is not completely understood and empirical evidence for its use is limited. This article provides a simplified explanation of variable positive airway pressure generation by HNF and related flushing of the anatomic dead space...
2017: Nederlands Tijdschrift Voor Geneeskunde
https://www.readbyqxmd.com/read/28157805/generalizability-concern-of-alveolar-dead-space-fraction-of-yehya-et-al
#15
Erik Koomen, Roelie M Wösten-van Asperen
No abstract text is available yet for this article.
February 2017: Pediatric Critical Care Medicine
https://www.readbyqxmd.com/read/27886421/pathophysiology-of-dyspnoea-in-acute-pulmonary-embolism-a-cross-sectional-evaluation
#16
Olivier Sanchez, Aurore Caumont-Prim, Elisabeth Riant, Laurent Plantier, Martin Dres, Bruno Louis, Marie-Anne Collignon, Benoit Diebold, Guy Meyer, Claudine Peiffer, Christophe Delclaux
BACKGROUND AND OBJECTIVE: Dyspnoea in pulmonary embolism (PE) remains poorly characterized. Little is known about how to measure intensity or about the underlying mechanisms that may be related to ventilatory abnormalities, alveolar dead space ventilation or modulating factors such as psychological modulate. We hypothesized that dyspnoea would mainly be associated with pulmonary vascular obstruction and its pathophysiological consequences, while the sensory-affective domain of dyspnoea would be influenced by other factors...
May 2017: Respirology: Official Journal of the Asian Pacific Society of Respirology
https://www.readbyqxmd.com/read/27849858/216-pulmonary-dead-space-fraction-and-extubation-success-in-children-after-cardiac-surgery
#17
Renee Devor, Chasity Wellnitz, Paul Kang, Muniza Siddiqui, John Nigro, Daniel Velez, Brigham Willis
No abstract text is available yet for this article.
December 2016: Critical Care Medicine
https://www.readbyqxmd.com/read/27761428/effects-of-flavonoids-from-martynia-annua-and-tephrosia-purpurea-on-cutaneous-wound-healing
#18
Santram Lodhi, Avijeet Jain, Alok Pal Jain, Rajesh Singh Pawar, Abhay Kumar Singhai
OBJECTIVE: Martynia annua L. (M. annua), (Martyniaccae) has been traditionally used in the treatment of epilepsy, sore throat and inflammatory disorders. The leaf paste is used topically on Tuberculosis of the lymphatic glands and wounds of domestic animals. Tephrosia purpurea (T. purpurea), (Fabaceae) has been used traditionally as a remedy for asthma, gonorrhea, rheumatism and ulcers. This study aimed to evaluate the potential wound healing effects of different fractions ofethanol extract of M...
September 2016: Avicenna Journal of Phytomedicine
https://www.readbyqxmd.com/read/27698207/high-flow-nasal-cannula-therapy-for-adult-patients
#19
REVIEW
Jian Zhang, Ling Lin, Konghan Pan, Jiancang Zhou, Xiaoyin Huang
High-flow nasal cannula (HFNC) oxygen therapy has several physiological advantages over traditional oxygen therapy devices, including decreased nasopharyngeal resistance, washing out of the nasopharyngeal dead space, generation of positive pressure in the pharynx, increasing alveolar recruitment in the lungs, humidification of the airways, increased fraction of inspired oxygen and improved mucociliary clearance. Recently, the use of HFNC in treating adult critical illness patients has significantly increased, and it is now being used in many patients with a range of different disease conditions...
December 2016: Journal of International Medical Research
https://www.readbyqxmd.com/read/27688911/can-transcutaneous-co2-tension-be-used-to-calculate-ventilatory-dead-space-a-pilot-study
#20
Pradeep H Lakshminarayana, Adiba A Geeti, Umer M Darr, David A Kaufman
Dead space fraction (V d/V t) measurement performed using volumetric capnography requires arterial blood gas (ABG) sampling to estimate the partial pressure of carbon dioxide (PaCO2). In recent years, transcutaneous capnography (PtcCO2) has emerged as a noninvasive method of estimating PaCO2. We hypothesized that PtcCO2 can be used as a substitute for PaCO2 in the calculation of V d/V t. In this prospective pilot comparison study, 30 consecutive postcardiac surgery mechanically ventilated patients had V d/V t calculated separately using volumetric capnography by substituting PtcCO2 for PaCO2...
2016: Critical Care Research and Practice
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