keyword
MENU ▼
Read by QxMD icon Read
search

respiratory physiology ventilation

keyword
https://www.readbyqxmd.com/read/28818484/the-physiology-of-submaximal-exercise-the-steady-state-concept
#1
REVIEW
Guido Ferretti, Nazzareno Fagoni, Anna Taboni, Paolo Bruseghini, Giovanni Vinetti
The steady state concept implies that the oxygen flow is invariant and equal at each level along the respiratory system. The same is the case with the carbon dioxide flow. This condition has several physiological consequences, which are analysed. First, we briefly discuss the mechanical efficiency of exercise and the energy cost of human locomotion, as well as the roles played by aerodynamic work and frictional work. Then we analyse the equations describing the oxygen flow in lungs and in blood, the effects of ventilation and of the ventilation - perfusion inequality, and the interaction between diffusion and perfusion in the lungs...
August 14, 2017: Respiratory Physiology & Neurobiology
https://www.readbyqxmd.com/read/28806218/hypoxemic-patients-with-bilateral-infiltrates-treated-with-high-flow-nasal-cannula-present-a-similar-pattern-of-biomarkers-of-inflammation-and-injury-to-acute-respiratory-distress-syndrome-patients
#2
Marina García-de-Acilu, Judith Marin-Corral, Antonia Vázquez, Laura Ruano, Mònica Magret, Ricard Ferrer, Joan R Masclans, Oriol Roca
OBJECTIVE: To examine whether patients with acute hypoxemia and bilateral opacities treated with high-flow nasal cannula and acute respiratory distress syndrome patients who were directly mechanically ventilated are similar in terms of lung epithelial, endothelial, and inflammatory biomarkers. DESIGN: Prospective, multicenter study. SETTING: ICUs at three university tertiary hospitals. PATIENTS: Intubated and nonintubated patients admitted to the ICU with acute hypoxemia (PaO2/FIO2 ≤ 300) and bilateral opacities...
August 10, 2017: Critical Care Medicine
https://www.readbyqxmd.com/read/28802543/outcomes-and-predictors-of-failure-of-non-invasive-ventilation-in-patients-with-community-acquired-pneumonia-in-the-emergency-department
#3
Amjad Al-Rajhi, Anwar Murad, P Z Li, Jason Shahin
OBJECTIVE: We set out to describe the use and analyze the predictors of non-invasive ventilation failure in patients with community-acquired pneumonia who receive non-invasive ventilation as first line ventilatory therapy in the emergency department. METHODS: A retrospective cohort study was conducted among consecutive patients with community acquired pneumonia requiring ventilator support presenting to two tertiary care university-affiliated emergency departments...
August 7, 2017: American Journal of Emergency Medicine
https://www.readbyqxmd.com/read/28777198/nosocomial-infections-during-extracorporeal-membrane-oxygenation-incidence-etiology-and-impacton-patients-outcome
#4
Giacomo Grasselli, Vittorio Scaravilli, Stefano Di Bella, Stefano Biffi, Michela Bombino, Nicolò Patroniti, Luca Bisi, Anna Maria Peri, Antonio Pesenti, Andrea Gori, Laura Alagna
OBJECTIVE: To study incidence, type, etiology, risk factors, and impact on outcome of nosocomial infections during extracorporeal membrane oxygenation. DESIGN: Retrospective analysis of prospectively collected data. SETTING: Italian tertiary referral center medical-surgical ICU. PATIENTS: One hundred five consecutive patients who were treated with extracorporeal membrane oxygenation from January 2010 to November 2015...
August 2, 2017: Critical Care Medicine
https://www.readbyqxmd.com/read/28775065/effect-of-hypoxia-and-hyperoxia-on-exercise-performance-in-healthy-individuals-and-in-patients-with-pulmonary-hypertension-a-systematic-review
#5
Silvia Ulrich, Simon Raphael Schneider, Konrad E Bloch
Exercise performance is determined by oxygen supply to working muscles and vital organs. In healthy individuals, exercise performance is limited in the hypoxic environment at altitude, when oxygen delivery is diminished due to the reduced alveolar and arterial oxygen partial pressures. In patients with pulmonary hypertension, exercise performance is already reduced near sea level due to impairments of the pulmonary circulation and gas exchange and, presumably, these limitations are more pronounced at altitude...
August 3, 2017: Journal of Applied Physiology
https://www.readbyqxmd.com/read/28774953/cerebrovascular-and-ventilatory-responses-to-acute-normobaric-hypoxia-in-girls-and-women
#6
Laura E Morris, Daniela Flück, Philip N Ainslie, Ali M McManus
Physiological responses to hypoxia in children are incompletely understood. We aimed to characterize cerebrovascular and ventilatory responses to normobaric hypoxia in girls and women. Ten healthy girls (9.9 ± 1.7 years; mean ± SD; Tanner stage 1 and 2) and their mothers (43.9 ± 3.5 years) participated. Internal carotid (ICA) and vertebral artery (VA) velocity, diameter and flow (Duplex ultrasound) was recorded pre- and post-1 h of hypoxic exposure (FIO2 = 0.126;~4000 m) in a normobaric chamber...
August 2017: Physiological Reports
https://www.readbyqxmd.com/read/28774204/apache-ii-score-cannot-predict-successful-weaning-from-prolonged-mechanical-ventilation
#7
Anna Rojek-Jarmuła, Rainer Hombach, Łukasz J Krzych
At least 5% of all intensive care unit patients require prolonged respiratory support. Multiple factors have been suggested as possible predictors of successful respiratory weaning so far. We sought to verify whether the Acute Physiology and Chronic Health Evaluation II (APACHE II) can predict freedom from prolonged mechanical ventilation (PMV) in patients treated in a regional weaning centre. The study group comprised 130 consecutive patients (age; median (interquartile range): 71 (62-77) years), hospitalized between 1 January 2012, and 31 December 2013...
August 2017: Chronic Respiratory Disease
https://www.readbyqxmd.com/read/28770543/feasibility-and-safety-of-virtual-reality-based-early-neurocognitive-stimulation-in-critically-ill-patients
#8
Marc Turon, Sol Fernandez-Gonzalo, Mercè Jodar, Gemma Gomà, Jaume Montanya, David Hernando, Raquel Bailón, Candelaria de Haro, Victor Gomez-Simon, Josefina Lopez-Aguilar, Rudys Magrans, Melcior Martinez-Perez, Joan Carles Oliva, Lluís Blanch
BACKGROUND: Growing evidence suggests that critical illness often results in significant long-term neurocognitive impairments in one-third of survivors. Although these neurocognitive impairments are long-lasting and devastating for survivors, rehabilitation rarely occurs during or after critical illness. Our aim is to describe an early neurocognitive stimulation intervention based on virtual reality for patients who are critically ill and to present the results of a proof-of-concept study testing the feasibility, safety, and suitability of this intervention...
December 2017: Annals of Intensive Care
https://www.readbyqxmd.com/read/28762180/optimum-support-by-high-flow-nasal-cannula-in-acute-hypoxemic-respiratory-failure-effects-of-increasing-flow-rates
#9
Tommaso Mauri, Laura Alban, Cecilia Turrini, Barbara Cambiaghi, Eleonora Carlesso, Paolo Taccone, Nicola Bottino, Alfredo Lissoni, Savino Spadaro, Carlo Alberto Volta, Luciano Gattinoni, Antonio Pesenti, Giacomo Grasselli
PURPOSE: Limited data exist on the correlation between higher flow rates of high-flow nasal cannula (HFNC) and its physiologic effects in patients with acute hypoxemic respiratory failure (AHRF). We assessed the effects of HFNC delivered at increasing flow rate on inspiratory effort, work of breathing, minute ventilation, lung volumes, dynamic compliance and oxygenation in AHRF patients. METHODS: A prospective randomized cross-over study was performed in non-intubated patients with patients AHRF and a PaO2/FiO2 (arterial partial pressure of oxygen/fraction of inspired oxygen) ratio of ≤300 mmHg...
July 31, 2017: Intensive Care Medicine
https://www.readbyqxmd.com/read/28761700/a-novel-treadmill-protocol-for-exercise-testing-in-children-the-british-columbia-children-s-hospital-protocol
#10
D Kathryn Duff, Astrid M De Souza, Derek G Human, James E Potts, Kevin C Harris
BACKGROUND: Exercise testing in children is widely recommended for a number of clinical and prescriptive reasons. Many institutions continue to use the Bruce protocol for treadmill testing; however, with its incremental changes in speed and grade, it has challenges for practical application in children. We have developed a novel institutional protocol (British Columbia Children's Hospital (BCCH)), which may have better utility in paediatric populations. AIM: To determine if our institutional protocol yields similar peak responses in minute ventilation (VE), oxygen consumption (VO2), carbon dioxide production (VCO2), respiratory exchange ratio (RER), metabolic equivalents (METS) and heart rate (HR) when compared with the traditional Bruce protocol...
2017: BMJ Open Sport & Exercise Medicine
https://www.readbyqxmd.com/read/28760461/effect-of-dead-space-on-breathing-stability-at-exercise-in-hypoxia
#11
Eric Hermand, François J Lhuissier, Jean-Paul Richalet
Recent studies have shown that normal subjects exhibit periodic breathing when submitted to concomitant environmental (hypoxia) and physiological (exercise) stresses. A mathematical model including mass balance equations confirmed the short period of ventilatory oscillations and pointed out an important role of dead space in the genesis of these phenomena. Ten healthy subjects performed mild exercise on a cycloergometer in different conditions: rest/exercise, normoxia/hypoxia and no added dead space/added dead space (aDS)...
July 29, 2017: Respiratory Physiology & Neurobiology
https://www.readbyqxmd.com/read/28758151/the-effect-of-diet-induced-serum-hypercholesterolemia-on-the-surfactant-system-and-the-development-of-lung-injury
#12
Scott Milos, Joshua Qua Hiansen, Brandon Banaschewski, Yi Y Zuo, Li-Juan Yao, Lynda A McCaig, James Lewis, Cory M Yamashita, Ruud A W Veldhuizen
Acute respiratory distress syndrome (ARDS) is a pulmonary disorder associated with alterations to the pulmonary surfactant system. Recent studies showed that supra-physiological levels of cholesterol in surfactant contribute to impaired function. Since cholesterol is incorporated into surfactant within the alveolar type II cells which derives its cholesterol from serum, it was hypothesized that serum hypercholesterolemia would predispose the host to the development of lung injury due to alterations of cholesterol content in the surfactant system...
September 2016: Biochemistry and Biophysics Reports
https://www.readbyqxmd.com/read/28751375/automated-full-range-pressure-volume-curves-in-mice-and-rats
#13
Annette Robichaud, Liah Fereydoonzad, Nathachit Limjunyawong, Richard Rabold, Benoit Allard, Andrea Benedetti, James G Martin, Wayne Mitzner
Pressure-volume (PV) curves constructed over the entire lung volume range can reliably detect functional changes in mouse models of lung diseases. In the present study, we constructed full-range PV curves in healthy and elastase-treated mice using either a classic manually-operated technique or an automated approach using a computer-controlled piston ventilator (flexiVent FX; SCIREQ Inc, Montreal, Qc, Canada). On the day of the experiment, subjects were anaesthetized, tracheotomized and mechanically ventilated...
July 27, 2017: Journal of Applied Physiology
https://www.readbyqxmd.com/read/28747467/isoflurane-ketamine-xylazine-and-urethane-markedly-alter-breathing-even-at-sub-therapeutic-doses
#14
Cory A Massey, George B Richerson
Anesthetics are widely used for animal research on respiratory control in vivo, but their effect on breathing and CO2 chemoreception has not been well characterized in mice, a species now often used for these studies. We previously demonstrated that 1% isoflurane markedly reduces the hypercapnic ventilatory response (HCVR) in adult mice in vivo and masks serotonin (5-hydroxytryptamine; 5-HT) neuron chemosensitivity in vitro Here we investigated effects of 0.5% isoflurane on breathing in adult mice, and also found a large reduction in the HCVR even at this sub-anesthetic concentration...
July 26, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/28745850/noninvasive-ventilation-for-patients-in-acute-respiratory-distress-an-update-digest
#15
Nikita Joshi, Molly K Estes, Kayla Shipley, Hyun-Chul Danny Lee, Milana Zaurova
Over the last 20 years, noninvasive ventilation (NIV) strategies have been used with increasing frequency. The ease of use of NIV makes it applicable to patients presenting in a variety of types of respiratory distress. In this review, the physiology of positive pressure ventilation is discussed, including indications, contraindications, and options for mask type and fit. Characteristics of patients who are most likely to benefit from NIV are reviewed, including those in respiratory distress from chronic obstructive pulmonary disease exacerbation and cardiogenic pulmonary edema...
February 22, 2017: Emergency Medicine Practice
https://www.readbyqxmd.com/read/28743338/-clinical-characteristics-and-prognosis-in-patients-with-high-plasma-level-of-procalcitonin-an-analysis-in-188-patients
#16
Chuli Pan, Wei Cui, Feifei Zhou, Junwei Tu, Xiuhui Lin, Libin Li, Gensheng Zhang
OBJECTIVE: To investigate the clinical characteristics and prognosis of patients with high level of plasma procalcitonin (PCT > 100 μg/L), and to improve the clinician's understanding, diagnosis and treatment of this kind of patients. METHODS: A retrospective study was conducted. The clinical data of patients with plasma PCT over 100 μg/L within 48 hours of admission admitted to Second Affiliated Hospital of Zhejiang University School of Medicine from February 2013 to December 2016 were collected, and the clinical characteristics were analyzed...
July 2017: Zhonghua Wei Zhong Bing Ji Jiu Yi Xue
https://www.readbyqxmd.com/read/28732512/prolonged-acute-care-and-post-acute-care-admission-and-recovery-of-physical-function-in-survivors-of-acute-respiratory-failure-a-secondary-analysis-of-a-randomized-controlled-trial
#17
Anna Neumeier, Amy Nordon-Craft, Dan Malone, Margaret Schenkman, Brendan Clark, Marc Moss
BACKGROUND: The proportion of survivors of acute respiratory failure is growing; yet, many do not regain full function and require prolonged admission in an acute or post-acute care facility. Little is known about their trajectory of functional recovery. We sought to determine whether prolonged admission influenced the trajectory of physical function recovery and whether patient age modified the recuperation rate. METHODS: We performed a secondary analysis of a randomized clinical trial of intensive physical therapy for patients with acute respiratory failure requiring mechanical ventilation for ≥4 days...
July 21, 2017: Critical Care: the Official Journal of the Critical Care Forum
https://www.readbyqxmd.com/read/28721821/current-perspectives-for-the-use-of-gonane-progesteronergic-drugs-in-the-treatment-of-central-hypoventilation-syndromes
#18
Camille Loiseau, Florence Cayetanot, Fanny Joubert, Anne-Sophie Perrin-Terrin, Philippe Cardot, Marie-Noëlle Fiamma, Alain Frugiere, Christian Straus, Laurence Bodineau
BACKGROUND: Central alveolar hypoventilation syndromes (CHS) encompass neurorespiratory diseases resulting from congenital or acquired neurological disorders. Hypercapnia, acidosis, and hypoxemia resulting from CHS negatively affect physiological functions and can be life-threatening. To date, the absence of pharmacological treatment implies that the patients must receive assisted ventilation throughout their lives. OBJECTIVE: To highlight the relevance of determining conditions in which using gonane synthetic progestins could be of potential clinical interest for the treatment of CHS...
July 19, 2017: Current Neuropharmacology
https://www.readbyqxmd.com/read/28707173/intraoperative-ventilation-of-morbidly-obese-patients-guided-by-transpulmonary-pressure
#19
Lars Eichler, Katarzyna Truskowska, A Dupree, P Busch, Alwin E Goetz, Christian Zöllner
BACKGROUND: Bariatric surgery has proven a successful approach in the treatment of morbid obesity and its concomitant diseases such as diabetes mellitus and arterial hypertension. Aiming for optimal management of this challenging patient cohort, tailored concepts directly guided by individual patient physiology may outperform standardized care. Implying esophageal pressure measurement and electrical impedance tomography-increasingly applied monitoring approaches to individually adjust mechanical ventilation in challenging circumstances like acute respiratory distress syndrome (ARDS) and intraabdominal hypertension-we compared our institutions standard ventilator regimen with an individually adjusted positive end expiratory pressure (PEEP) level aiming for a positive transpulmonary pressure (P L) throughout the respiratory cycle...
July 14, 2017: Obesity Surgery
https://www.readbyqxmd.com/read/28704507/regular-moist-snuff-dipping-does-not-affect-endurance-exercise-performance
#20
Frida Björkman, Fredrik Edin, C Mikael Mattsson, Filip Larsen, Björn Ekblom
Physiological and medical effects of snuff have previously been obtained either in cross-sectional studies or after snuff administration to non-tobacco users. The effects of snuff cessation after several years of daily use are unknown. 24 participants with >2 years of daily snuff-use were tested before and after >6 weeks snuff cessation (SCG). A control group (CO) of 11 snuff users kept their normal habits. Resting heart rate (HR) and blood pressure (BP) were significantly lower in SCG after snuff cessation, and body mass was increased by 1...
2017: PloS One
keyword
keyword
55755
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"