keyword
MENU ▼
Read by QxMD icon Read
search

respiratory physiology ventilation

keyword
https://www.readbyqxmd.com/read/28650070/the-human-ventilatory-response-to-stress-rate-or-depth
#1
Michael J Tipton, Abbi Harper, Julian F R Paton, Joseph T Costello
Many stressors cause an increase in ventilation in humans. This is predominantly reported as an increase in minute ventilation (V̇E ). But, the same V̇E can be achieved by a wide variety of changes in the depth (tidal volume, VT ) and number of breaths (respiratory frequency, ƒR). This review investigates the impact of stressors including: cold, heat, hypoxia, pain and panic on the contributions of ƒR and VT to V̇E to see if they differ with different stressors. Where possible we also consider the potential mechanisms that underpin the responses identified, and propose mechanisms by which differences in ƒR and VT are mediated...
June 26, 2017: Journal of Physiology
https://www.readbyqxmd.com/read/28640969/control-of-breathing-and-ventilatory-acclimatization-to-hypoxia-in-deer-mice-native-to-high-altitudes
#2
Catherine M Ivy, Graham R Scott
AIM: We compared the control of breathing and heart rate by hypoxia between high- and low-altitude populations of Peromyscus mice, to help elucidate the physiological specializations that help high-altitude natives cope with O2 limitation. METHODS: Deer mice (P. maniculatus) native to high altitude and congeneric mice native to low altitude (P. leucopus) were bred in captivity at sea level. The F1 progeny of each population were raised to adulthood and then acclimated to normoxia or hypobaric hypoxia (12 kPa, simulating hypoxia at ~4300 m) for 5 months...
June 22, 2017: Acta Physiologica
https://www.readbyqxmd.com/read/28640662/using-probiotics-in-clinical-practice-where-are-we-now-a-review-of-existing-meta-analyses
#3
Mariangela Rondanelli, Milena Anna Faliva, Simone Perna, Attilio Giacosa, Gabriella Peroni, Anna Maria Castellazzi
The scientific literature has demonstrated that probiotics have a broad spectrum of activity, although often the results are contradictory. This study provides a critical overview of the current meta-analyses that have evaluated the efficacy of probiotics in physiological and pathological conditions, such as metabolic disease, antibiotic-associated and Clostridium difficile-associated diarrhea, IBS, constipation, IBD, chemotherapy-associated diarrhea, respiratory tract infection, ventilator-associated pneumonia, NAFLD, liver encephalopathy, periodontitis, depression, vaginosis, urinary tract infections, pancreatitis, incidence of ventilator-associated pneumonia, hospital infection and stay in ICU, mortality of post-trauma patients, necrotising enterocolitis in premature infants...
June 22, 2017: Gut Microbes
https://www.readbyqxmd.com/read/28624991/a-new-global-and-comprehensive-model-for-icu-ventilator-performances-evaluation
#4
Nicolas S Marjanovic, Agathe De Simone, Guillaume Jegou, Erwan L'Her
BACKGROUND: This study aimed to provide a new global and comprehensive evaluation of recent ICU ventilators taking into account both technical performances and ergonomics. METHODS: Six recent ICU ventilators were evaluated. Technical performances were assessed under two FIO2 levels (100%, 50%), three respiratory mechanics combinations (Normal: compliance [C] = 70 mL cmH2O(-1)/resistance [R] = 5 cmH2O L(-1) s(-1); Restrictive: C = 30/R = 10; Obstructive: C = 120/R = 20), four exponential levels of leaks (from 0 to 12...
December 2017: Annals of Intensive Care
https://www.readbyqxmd.com/read/28614863/-anesthetic-management-in-thoracic-trauma-patients
#5
Alf Kozian, Astrid Bergmann, Thomas Hachenberg, Thomas Schilling
In daily practice, management of patients with blunt thoracic trauma is challenging for the anesthetist. Injuries of airways, lungs, diaphragm, heart and large vessels are the main difficulties.Respiratory and circulatory physiology in general is affected by general anesthesia, which may result in an increased number of perioperative complications. Therefore, anesthetic management of patients with thoracic trauma needs to address different clinical topics: management of difficult airways, intrinsic effects of anesthetics and mechanical ventilation on respiratory and cardiac function, the adequate replacement of blood loss as well as type and extent of the surgical intervention...
June 2017: Anästhesiologie, Intensivmedizin, Notfallmedizin, Schmerztherapie: AINS
https://www.readbyqxmd.com/read/28614095/the-value-of-dynamic-preload-variables-during-spontaneous-ventilation
#6
Azriel Perel
PURPOSE OF REVIEW: To discuss the physiological significance and clinical value of dynamic preload variables in spontaneously breathing patients. RECENT FINDINGS: Dynamic preload variables reflect the response of the cardiac output to a modification of preload and can therefore be used to assess fluid responsiveness. Continuous dynamic parameters that are calculated from the variations in the arterial and plethysmographic waveforms following a mechanical breath have been shown to predict fluid responsiveness much better than static preload parameters...
June 12, 2017: Current Opinion in Critical Care
https://www.readbyqxmd.com/read/28608135/can-proportional-ventilation-modes-facilitate-exercise-in-critically-ill-patients-a-physiological-cross-over-study-pressure-support-versus-proportional-ventilation-during-lower-limb-exercise-in-ventilated-critically-ill-patients
#7
Evangelia Akoumianaki, Nicolas Dousse, Aissam Lyazidi, Jean-Claude Lefebvre, Severine Graf, Ricardo Luiz Cordioli, Nathalie Rey, Jean-Christophe Marie Richard, Laurent Brochard
BACKGROUND: Early exercise of critically ill patients may have beneficial effects on muscle strength, mass and systemic inflammation. During pressure support ventilation (PSV), a mismatch between demand and assist could increase work of breathing and limit exercise. A better exercise tolerance is possible with a proportional mode of ventilation (Proportional Assist Ventilation, PAV+ and Neurally Adjusted Ventilatory Assist, NAVA). We examined whether, in critically ill patients, PSV and proportional ventilation have different effects on respiratory muscles unloading and work efficiency during exercise...
December 2017: Annals of Intensive Care
https://www.readbyqxmd.com/read/28598919/cardiorespiratory-alterations-following-acute-normovolemic-hemodilution-in-a-pediatric-and-an-adult-porcine-model-a-prospective-interventional-study
#8
Gergely Albu, Cédric Sottas, Mirko Dolci, Magali Walesa, Ferenc Peták, Walid Habre
BACKGROUND: Acute normovolemic hemodilution (ANH) is considered as a blood-sparing intervention during the perioperative management. We aimed at comparing the cardiopulmonary consequences of ANH between adult pigs and weaned piglets to establish the effects of lowering hematocrit in these age groups, and thereby testing the hypothesis that difference in the age-related physiological behavior will be reflected in the cardiorespiratory changes following ANH. METHODS: ANH was achieved in anesthetized, mechanically ventilated adult minipigs and 5-week-old weaned piglets by stepwise blood withdrawal (10 mL/kg) with crystalloids replacement...
June 8, 2017: Anesthesia and Analgesia
https://www.readbyqxmd.com/read/28592029/-effects-of-noninvasive-proportional-assist-vs-pressure-support-ventilation-on-respiratory-work-in-chronic-obstructive-pulmonary-disease-patients-with-hypercapnia
#9
J H Zhang, Q Luo, H J Zhang, R C Chen
Objective: To investigate the effect of noninvasive proportional assist ventilation (PAV) on respiratory work in chronic obstructive pulmonary disease(COPD) patients, in comparison to noninvasive pressure support ventilation(PSV). Methods: Ten severe COPD patients with hypercapnia during acute exacerbation were examined. The baseline inspiratory pressure of PSV (PS) and the assistance level of PAV(PA) were titrated by patients' tolerance. In addition to the baseline PS and PA, an additional decrease by 25% (PS-=75% PS, PA-=75% PA) or increase by 25% (PS+ =125% PS, PA+ =125% PA) of the assist level were applied to the patients...
June 12, 2017: Chinese Journal of Tuberculosis and Respiratory Diseases
https://www.readbyqxmd.com/read/28588118/clinical-management-strategies-for-airway-pressure-release-ventilation-a-survey-of-clinical-practice
#10
Andrew G Miller, Michael A Gentile, John D Davies, Neil R MacIntyre
BACKGROUND: Airway pressure release ventilation (APRV) is a commonly used mode of ventilation designed to increase mean airway pressure and thus oxygenation. Different strategies for clinical management have been described in the literature but are largely based on physiologic concepts, animal data, and small clinical trials. The purpose of this study was to determine how APRV is currently managed by surveying practicing respiratory therapists with experience using APRV. METHODS: A 15-item survey was developed by the authors and posted on the AARConnect online media platform in January 2016 after being declared exempt by our institution's institutional review board...
June 6, 2017: Respiratory Care
https://www.readbyqxmd.com/read/28574212/calculation-algorithms-alter-the-breath-by-breath-gas-exchange-values-when-abrupt-changes-in-ventilation-occur
#11
Valentina Cettolo, Maria Pia Francescato
The automatic metabolic units calculate breath-by-breath gas exchange from the expiratory data only, applying an algorithm ('expiration-only' algorithm) that neglects the changes in the lung gas stores. These last are theoretically taken into account by a recently proposed algorithm, based on an alternative view of the respiratory cycle ('alternative respiratory cycle' algorithm). The performance of the two algorithms was investigated where changes in the lung gas stores were induced by abrupt increases in ventilation above the physiological demand...
June 2, 2017: Clinical Physiology and Functional Imaging
https://www.readbyqxmd.com/read/28573250/the-use-of-rheum-palmatum-l-in-the-treatment-of-acute-respiratory-distress-syndrome-a-meta-analysis-of-randomized-controlled-trials
#12
Tie-Zhu Yang, Yan Liu, Yue-Yun Liu, Xiu-Fang Ding, Jia-Xu Chen, Mei-Jing Kou, Xiao-Juan Zou
BACKGROUND: Chinese medicine theory shows that "lung being connected with large intestine", and the modern western medicine also shows that the lung and intestinal tract affect each other in physiological and pathological conditions. If the lung ventilation dysfunction is caused by inflammatory exudate or secretions obstruction of the small airway ventilation, blood gas partial pressure is increased and intestinal gas absorption difficulty may lead to intestinal inflation and dysfunction (Wang N et al...
2017: African Journal of Traditional, Complementary, and Alternative Medicines: AJTCAM
https://www.readbyqxmd.com/read/28569555/sleep-and-mechanical-ventilation-in-stable-copd-patients
#13
Léo Grassion, Jésus Gonzalez-Bermejo
Respiratory work is physiologically increased during sleep and leads to severe alterations in COPD patients, especially by raising sleep hypoventilation. The diurnal impact of these nocturnal events may have been underestimated in COPD patients. Impaired sleep and the increase of respiratory work may be one of the major trigger of diurnal events like hypoventilation, exacerbation and even mortality. One of the most commonly used nocturnal treatments at the present time is noninvasive ventilation (NIV). However, there is an on-going debate concerning the indications and objectives of NIV in COPD patients...
June 1, 2017: COPD
https://www.readbyqxmd.com/read/28561251/management-of-acute-respiratory-failure-in-pregnancy
#14
Stephen E Lapinsky
Respiratory failure affects up to 1 in 500 pregnancies, more commonly in the postpartum period. The causes of respiratory failure include several pregnancy-specific conditions such as preeclampsia, amniotic fluid embolism, and peripartum cardiomyopathy. Pregnancy may also increase the risk or severity of other conditions, such as asthma, thromboembolism, viral pneumonitis, and gastric acid aspiration. Changes to maternal respiratory physiology and the presence of a fetus may affect the assessment and management of these patients...
April 2017: Seminars in Respiratory and Critical Care Medicine
https://www.readbyqxmd.com/read/28526233/keratinocyte-growth-factor-for-the-treatment-of-the-acute-respiratory-distress-syndrome-kare-a-randomised-double-blind-placebo-controlled-phase-2-trial
#15
Daniel F McAuley, Lj Mark Cross, Umar Hamid, Evie Gardner, J Stuart Elborn, Kathy M Cullen, Ahilanandan Dushianthan, Michael Pw Grocott, Michael A Matthay, Cecilia M O'Kane
BACKGROUND: Data from in-vitro, animal, and human lung injury models suggest that keratinocyte growth factor (KGF) might be beneficial in acute respiratory distress syndrome (ARDS). The objective of this trial was to investigate the effect of KGF in patients with ARDS. METHODS: We did a double-blind, allocation concealed, randomised, placebo-controlled phase 2 trial in two intensive care units in the UK, involving patients fulfilling the American-European Consensus Conference Definition of ARDS...
May 16, 2017: Lancet Respiratory Medicine
https://www.readbyqxmd.com/read/28524027/-effect-of-chest-physiotherapy-in-patients-undergoing-mechanical-ventilation-a-prospective-randomized-controlled-trial
#16
Hui Zeng, Zhen Zhang, Yuan Gong, Miao Chen
OBJECTIVE: To investigate the effect of chest physiotherapy (CPT) on patients undergoing mechanical ventilation (MV). METHODS: A prospective randomized controlled trial (RCT) was conducted. Sixty-eight adult patients undergoing invasive MV over 48 hours admitted to intensive care unit (ICU) of Affiliated Hospital of Zunyi Medical College from December 2014 to October 2016 were enrolled, and they were divided into CPT group (n = 37) and control group (n = 31) by random number table...
May 2017: Zhonghua Wei Zhong Bing Ji Jiu Yi Xue
https://www.readbyqxmd.com/read/28522760/on-the-existence-of-a-central-respiratory-oxygen-sensor
#17
Alexander V Gourine, Gregory D Funk
A commonly held view that dominates both the scientific and educational literature is that in terrestrial mammals the central nervous system lacks a physiological hypoxia sensor capable of triggering increases in lung ventilation in response to decreases in PO2 of the brain parenchyma. Indeed, a normocapnic hypoxic ventilatory response has never been observed in humans following bilateral resection of the carotid bodies. In contrast, almost complete or partial recovery of the hypoxic ventilatory response after denervation/removal of the peripheral respiratory oxygen chemoreceptors has been demonstrated in many experimental animals when assessed in an awake state...
May 18, 2017: Journal of Applied Physiology
https://www.readbyqxmd.com/read/28510504/cardiopulmonary-exercise-testing-basics-of-methodology-and-measurements
#18
Alessandro Mezzani
Cardiopulmonary exercise testing adds measurement of ventilation and volume of oxygen uptake and exhaled carbon dioxide to routine physiological and performance parameters obtainable from conventional exercise testing, furnishing an all-round vision of the systems involved in both oxygen transport from air to mitochondria and its utilization during exercise. Peculiarities of cardiopulmonary exercise testing methodology are the use of ramp protocols and calibration procedures for flow meters and gas analyzers...
May 16, 2017: Annals of the American Thoracic Society
https://www.readbyqxmd.com/read/28494170/why-high-intensity-nppv-is-favourable-to-low-intensity-nppv-clinical-and-physiological-reasons
#19
S B Schwarz, F S Magnet, W Windisch
High-intensity non-invasive positive pressure ventilation (NPPV) was originally described for chronic hypercapnic chronic obstructive pulmonary disease (COPD) patients in 2009, and refers to a specific ventilatory approach whereby NPPV settings are aimed at achieving the lowest arterial partial pressure of carbon dioxide (PaCO2) values possible. Thus, high-intensity NPPV requires ventilator settings to be increased in a stepwise approach to either an individually tolerated maximum, or to the levels necessary to achieve normocapnia...
May 11, 2017: COPD
https://www.readbyqxmd.com/read/28488367/chemosensitive-phox2b-expressing-neurons-are-crucial-for-hypercapnic-ventilatory-response-in-the-nucleus-tractus-solitarius
#20
Congrui Fu, Jinyu Xue, Ri Wang, Jinting Chen, Lan Ma, Yixian Liu, Xuejiao Wang, Fang Guo, Yi Zhang, Xiangjian Zhang, Sheng Wang
The nucleus tractus solitarius (NTS) neurons have been thought to function as central respiratory chemoreceptors. However, it remains unknown regarding the common molecular marker defined for these neurons. Here we ask whether paired-like homeobox 2b (Phox2b)-expressing NTS neurons are recruited in hypercapnic ventilatory response (HCVR) and whether these neurons exhibit intrinsic chemosensitivity. HCVR was assessed using whole body plethysmography and neuronal chemosensitivity was examined by patch clamp recordings in brainstem slices or dissociated neurons from Phox2b-EGFP transgenic mice...
May 10, 2017: Journal of Physiology
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"