Search results for "Respiration"
showing 10 items of 538 documents
Categorizing the Role of Respiration in Cardiovascular and Cerebrovascular Variability Interactions
2022
Objective: Respiration disturbs cardiovascular and cerebrovascular controls but its role is not fully elucidated. Methods: Respiration can be classified as a confounder if its observation reduces the strength of the causal relationship from source to target. Respiration is a suppressor if the opposite situation holds. We prove that a confounding/suppression (C/S) test can be accomplished by evaluating the sign of net redundancy/synergy balance in the predictability framework based on multivariate autoregressive modelling. In addition, we suggest that, under the hypothesis of Gaussian processes, the C/S test can be given in the transfer entropy decomposition framework as well. Experimental p…
Polysomnography and ApneaGraph in patients with sleep-related breathing disorders.
2007
<i>Purpose:</i> To evaluate whether ApneaGraph (AG) and polysomnography (PSG) deliver comparable results in patients with sleep-related breathing disorders. <i>Procedures:</i> A prospective study was performed, which included 14 patients with obstructive sleep apnea syndrome. Apnea-hypopnea index (AHI), hypopnea index (HI), apnea index (AI), obstructive, central and mixed apnea, oxygen saturation (SaO<sub>2</sub>), pulse and body position were simultaneously assessed by PSG and AG in each individual. <i>Results:</i> There was a good correlation between measurements of AG and PSG for AHI, pulse, SaO<sub>2</sub>, body position and ce…
Cross validation of the 1-mile walking test for men with mental retardation.
1997
The purpose of this study was to cross validate the equation developed by Rintala et al. (1992) to estimate the cardiorespiratory efficiency of men with mental retardation (MR). Subjects were 19 healthy men (27 ± 8 yr) with MR (IQ = 58 ± 12). Following familiarization, a graded maximal treadmill test and two 1-mile walk tests (Rockport Fitness Walking Test, RFWT) were administered. The peak VO 2 value was the criterion measure used to cross validate the equation. The equation was: Peak VO 2 (ml.kg -1 .min -1 ) = 101.92 - 2.356 (MILE) -0.420 (WEIGHT). The mean differences were 2.04 (MILE 1 )(P = 0.02) and 2.43 (MILE 2 )(P = 0.004) ml.kg -1 .min -1 . A significant positive correlation was fou…
Exhaled Nitric Oxide and Bronchial Responsiveness to Adenosine 5′-Monophosphate in Subjects With Allergic Rhinitis
2002
Study objectives: To determine differences in exhaled nitric oxide (ENO) between subjects with allergic rhinitis with and without increased responsiveness to direct and indirect bronchoconstrictor agents. Study design: Cross-sectional study with the order of challenge tests randomized. Setting: Specialist allergy unit in a university hospital. Patients: Thirty-eight subjects without asthma with allergic rhinitis and 10 healthy nonatopic control subjects. Measurements and results: Participants were challenged with increasing concentrations of adenosine 5monophosphate (AMP) and methacholine. ENO was measured with the singleexhalation method. A positive response to both bronchoconstrictor agen…
Non-contact breath sampling for sensor-based breath analysis
2019
Breath analysis holds great promise for real-time and non-invasive medical diagnosis. Thus, there is a considerable need for simple-in-use and portable analyzers for rapid detection of breath indicators for different diseases in their early stages. Sensor technology meets all of these demands. However, miniaturized breath analyzers require adequate breath sampling methods. In this context, we propose non-contact sampling; namely the collection of breath samples by exhalation from a distance into a miniaturized collector without bringing the mouth into direct contact with the analyzing device. To evaluate this approach different breathing maneuvers have been tested in a real-time regime on a…
18-yr cumulative incidence of respiratory/allergic symptoms/diseases and risk factors in the Pisa epidemiological study
2019
Abstract Background Few population-based studies on the effects of environmental exposure variation exist. Aim Assessing respiratory symptom/disease incidence related to risk factor exposure changes. Methods A longitudinal general population sample from two surveys (PISA2:1991–1993; PISA3:2009–2011; no. = 970), aged ≥20 years at baseline, completed a questionnaire on respiratory symptoms/diseases, risk factor exposure and performed spirometry. 18-year follow-up cumulative incidence of respiratory symptoms/diseases and longitudinal changes (persistence, incidence, remittance) in risk factor exposure were computed. Results Cumulative incidence values were: 3.2% (corresponding to a 1.8‰/year i…
Airway inflammation in nonasthmatic amateur runners
2001
Elite athletes show a high prevalence of symptoms and signs of asthma, but no study has assessed the acute effects of endurance exercise on airway cells in nonasthmatic athletes. We measured exhaled nitric oxide (NO) and collected samples of induced sputum after 3% NaCl aerosol administration for 20 min in nonasthmatic middle-aged amateur runners after the Fourth Palermo International Marathon and 6–9 wk later (habitual training period) at baseline. After the marathon, exhaled NO ( n = 9 subjects) was higher [27 ± 9 parts/billion (ppb)] than at baseline (12 ± 4 ppb; P < 0.0005). Polymorphonuclear neutrophil (PMN) counts in induced sputum were much higher in runners (91.2 ± 3.6% of total…
Chest wall mechanics during pressure support ventilation.
2005
Introduction During pressure support ventilation (PSV) a part of the breathing pattern is controlled by the patient, and synchronization of respiratory muscle action and the resulting chest wall kinematics is a valid indicator of the patient's adaptation to the ventilator. The aim of the present study was to analyze the effects of different PSV settings on ventilatory pattern, total and compartmental chest wall kinematics and dynamics, muscle pressures and work of breathing in patients with acute lung injury. Method In nine patients four different levels of PSV (5, 10, 15 and 25 cmH2O) were randomly applied with the same level of positive end-expiratory pressure (10 cmH2O). Flow, airway ope…
Performance of EasyBreath Decathlon Snorkeling mask for delivering continuous positive airway pressure
2021
AbstractDuring the COVID-19 pandemic, the need for noninvasive respiratory support devices has dramatically increased, sometimes exceeding hospital capacity. The full-face Decathlon snorkeling mask, EasyBreath (EB mask), has been adapted to deliver continuous positive airway pressure (CPAP) as an emergency respiratory interface. We aimed to assess the performance of this modified EB mask and to test its use during different gas mixture supplies. CPAP set at 5, 10, and 15 cmH2O was delivered to 10 healthy volunteers with a high-flow system generator set at 40, 80, and 120 L min−1 and with a turbine-driven ventilator during both spontaneous and loaded (resistor) breathing. Inspiratory CO2 par…
Psychophysiological and vocal measures in the detection of guilty knowledge.
2004
The Guilty Knowledge Test (GKT) and its variant, the Guilty Actions Test (GAT), are both psychophysiological questioning techniques aiming to detect guilty knowledge of suspects or witnesses in criminal and forensic cases. Using a GAT, this study examined the validity of various physiological and vocal measures for the identification of guilty and innocent participants in a mock crime paradigm. Electrodermal, respiratory, and cardiovascular measures successfully differentiated between the two groups. A logistic regression model based on these variables achieved hit rates of above 90%. In contrast to these results, the vocal measures provided by the computerized voice stress analysis system …