Search results for "thing"

Impact of Nonstationarities on Short Heart Rate Variability Recordings During Obstructive Sleep Apnea

2017

Obstructive sleep apnea (OSA) is a sleep disorder characterized by breathing pauses due to collapse of the upper airways. During OSA the autonomic modulation, as noninvasively assessed through heart period (HP) variability, is altered in a time-varying way even though time-varying properties of HP fluctuations are often disregarded by HP variability studies. We performed a time domain analysis computed over very short epochs corresponding to the sole OSA events explicitly accounting for HP variability nonstationarities. Length-matched epochs were extracted during OSA and quiet sleep (SLEEP) in 13 subjects suffering from OSA (11 males, age 55±11, apnea-hypopnea index 44±19). Mean HP, varianc…

Sacubitril/Valsartan Improves Autonomic Function and Cardiopulmonary Parameters in Patients with Heart Failure with Reduced Ejection Fraction

2020

Background: Heart rate recovery (HRR) is a marker of vagal tone, which is a powerful predictor of mortality in patients with cardiovascular disease. Sacubitril/valsartan (S/V) is a treatment for heart failure with reduced ejection fraction (HFrEF), which impressively impacts cardiovascular outcome. This study aims at evaluating the effects of S/V on HRR and its correlation with cardiopulmonary indexes in HFrEF patients. Methods: Patients with HFrEF admitted to outpatients&rsquo

Slow 0.1 Hz Breathing and Body Posture Induced Perturbations of RRI and Respiratory Signal Complexity and Cardiorespiratory Coupling

2020

Objective: We explored the physiological background of the non-linear operating mode of cardiorespiratory oscillators as the fundamental question of cardiorespiratory homeodynamics and as a prerequisite for the understanding of neurocardiovascular diseases. We investigated 20 healthy human subjects for changes using electrocardiac RR interval (RRI) and respiratory signal (Resp) Detrended Fluctuation Analysis (DFA, α1RRI, α2RRI, α1Resp, α2Resp), Multiple Scaling Entropy (MSERRI1−4, MSERRI5−10, MSEResp1−4, MSEResp5−10), spectral coherence (CohRRI−Resp), cross DFA (ρ1 and ρ2) and cross MSE (XMSE1−4 and XMSE5−10) indices in four physiological conditions: supine with spontaneous breathing, stand…

Information domain approach to the investigation of cardio-vascular, cardio-pulmonary, and vasculo-pulmonary causal couplings

2011

The physiological mechanisms related to cardio-vascular (CV), cardio-pulmonary (CP), and vasculo-pulmonary (VP) regulation may be probed through multivariate time series analysis tools. This study applied an information domain approach for the evaluation of non-linear causality to the beat-to-beat variability series of heart period (t), systolic arterial pressure (s), and respiration (r) measured during tilt testing and paced breathing (PB) protocols. The approach quantifies the causal coupling from the series i to the series j (C(ij)) as the amount of information flowing from i to j. A measure of directionality is also obtained as the difference between two reciprocal causal couplings (D(i…

A survey on the thermal conditions experienced by a surgical team

2007

The complex environment of the operating theatre is shared by a group of people having highly different needs: on one side, there is a surgical team whose work may last many hours and, on the other, an anaesthetized patient often subject to liquid infusion. Up to now, little consideration has been given to the different needs of the surgical team who may be affected according to their positions with respect to the scialytic lamp and their particular task. Clothing influences the comfort of the surgical team to a considerable degree: in fact, in some surgery (orthopaedics, neurosurgery and so on), surgeons and assistants must wear paper overalls beneath non-breathable plastic overalls and p…

2019

Postoperative pulmonary complications (PPC) may result in longer duration of in-hospital stay and even mortality. Both thoracic surgery and intraoperative mechanical ventilation settings add considerably to the risk of PPC. It is unclear if one-lung ventilation (OLV) for thoracic surgery with a strategy of intraoperative high positive end-expiratory pressure (PEEP) and recruitment maneuvers (RM) reduces PPC, compared to low PEEP without RM. PROTHOR is an international, multicenter, randomized, controlled, assessor-blinded, two-arm trial initiated by investigators of the PROtective VEntilation NETwork. In total, 2378 patients will be randomly assigned to one of two different intraoperative m…

Performance and work of nasal breathing

2021

Abstract OBJECTIVE. To evaluate performance (Q) and work (W) of nasal breathing as potential parameters in functional diagnostic of nasal obstruction. MATERIAL AND METHODS. We included in our study 250 patients and we measured by 4-phase-rhinomanometry with decongestion test. We calculated performance Q of the “representative breath” in inspiration and expiration and in total breath, maximal performance Q (Qmax), Work W of nasal breathing in mJ and in mJ/litre and Q in J/min. RESULTS. The interquartile range of Win for representative breath before decongestion is 356 mJ/l, Wex 308 mJ/l, while after decongestion Win is 264 mJ/l and Wex 220 mJ/l. There is no significant difference between wor…

Activation of Astrocytes in the Persistence of Post-hypoxic Respiratory Augmentation

2021

Acute hypoxia increases ventilation. After cessation of hypoxia loading, ventilation decreases but remains above the pre-exposure baseline level for a time. However, the mechanism of this post-hypoxic persistent respiratory augmentation (PHRA), which is a short-term potentiation of breathing, has not been elucidated. We aimed to test the hypothesis that astrocytes are involved in PHRA. To this end, we investigated hypoxic ventilatory responses by whole-body plethysmography in unanesthetized adult mice. The animals breathed room air, hypoxic gas mixture (7% O2, 93% N2) for 2min, and again room air for 10min before and after i.p. administration of low (100mg/kg) and high (300mg/kg) doses of a…

Severity Of Sleep Disordered Breathing Is An Independent Predictor Of Glycemic Health: The European Sleep Cohort (ESADA) Study

2012

Resumption of Ventilation at the End of Obstructive Sleep Apneas is not Determined by Diaphragmatic Fatigue

1988

In patients affected by obstructive sleep apnea syndrome (OSAS) a progressive increase of the force developed by the respiratory muscles is usually observed during the occlusive phase before upper airway patency is resumed (Onal and Lopata, 1986).