Search results for "Respiration"
showing 10 items of 538 documents
Action of metyrapone on the redox state of free nicotinamide-adenine dinucleotide and on oxygen consumption of perfused rat livers and isolated mitoc…
1971
Metyrapone [2-methyl-1,2-bis-(3-pyridyl)-1-propanone] in a concentration of 5 mM increased the lactate/pyruvate ratio and theΒ-hydroxybutyrate/ acetoacetate ratio in the perfusion fluid of the isolated rat liver by a factor of 6 indicating a considerable shift in the ratio of free [NAD]/[NADH] in both the cytoplasmic and the mitochondrial compartment. Oxygen uptake of the isolated liver was decreased to about one half. The onset of the inhibitory effect on the respiration of the isolated organ was immediate. The inhibition lasted for at least 1 h.
Protective Mechanical Ventilation during General Anesthesia for Open Abdominal Surgery Improves Postoperative Pulmonary Function
2013
Abstract Background: The impact of intraoperative ventilation on postoperative pulmonary complications is not defined. The authors aimed at determining the effectiveness of protective mechanical ventilation during open abdominal surgery on a modified Clinical Pulmonary Infection Score as primary outcome and postoperative pulmonary function. Methods: Prospective randomized, open-label, clinical trial performed in 56 patients scheduled to undergo elective open abdominal surgery lasting more than 2 h. Patients were assigned by envelopes to mechanical ventilation with tidal volume of 9 ml/kg ideal body weight and zero-positive end-expiratory pressure (standard ventilation strategy) or tidal vol…
Ventilation volumes with different self-inflating bags with reference to the ERC guidelines for airway management: comparison of two compression tech…
2000
The 1998 ERC-guidelines for airway-management recommend an tidal volume of 400-600 ml for adults undergoing CPR. As commercially available self-inflating bags were designed to meet former recommendations (800-1200 ml) we investigated how to meet the latest recommendations with these bags. We combined the head of a training manikin (Laerdal Medical) and a standard lung (VTTL; Michigan Instrument), adjusted to a physiological compliance and resistance. Volume was measured with a Wright spirometer (BOC). Seven self-inflating bags were investigated. Tests were carried out by ten people (five female and five male) for 5 min each using two different techniques. Technique 1: standard ventilation w…
Noninvasive respiratory muscle aids during PEG placement in ALS patients with severe ventilatory impairment.
2010
Abstract Although no clear recommendations are given about when percutaneous endoscopic gastrostomy (PEG) should be placed in amyotrophic lateral sclerosis (ALS) patients, some experts underline the risk of respiratory complications when patients had severe ventilatory muscle impairment (SVMI). Aim To evaluate the efficacy of noninvasive ventilation (NIV) and mechanically assisted cough (MAC) to avoid respiratory complications related to PEG placement in ALS patients with SVMI. Material and methods Prospective study including ALS patients who had chosen to have PEG placement timed by swallowing dysfunction with the aid of NIV and MAC if needed. PEG was carried out under volume-cycled NIV th…
Changes in cortico-spinal excitability following uphill versus downhill treadmill exercise
2017
International audience; An acute bout of aerobic exercise induces neuroplasticity in the motor cortex. Moreover, paired associative stimulation (PAS) is known to induce neuroplasticity in M1. However, the possible influence of the type of exercise on the neuroplastic changes remains unknown. The present study investigated the effects of two different modes of muscle contraction produced during locomotor exercise on changes in corticospinal (CS) excitability. Subjects performed two 30-min treadmill exercises at an intensity corresponding to 60% of their maximal heart rate with either a +10% (uphill) or -10% (downhill) slope. These exercises were followed or not by paired associative stimulat…
Closed-Loop Automatic Oxygen Control (CLAC) in Preterm Infants: A Randomized Controlled Trial
2014
BACKGROUND AND OBJECTIVE: In preterm infants receiving supplemental oxygen, routine manual control (RMC) of the fraction of inspired oxygen (FIO2) is often difficult and time consuming. We developed a system for closed-loop automatic control (CLAC) of the FIO2 and demonstrated its short-term safety and efficacy in a single-center study. The objective of this study was to test the hypothesis that this system is more effective than RMC alone in maintaining arterial oxygen saturation within target levels when evaluated over 24 hours under routine conditions and with different target levels. METHODS: We performed a multicenter, randomized controlled, crossover clinical trial in 34 preterm infa…
Evolution Over Time of Ventilatory Management and Outcome of Patients With Neurologic Disease
2021
OBJECTIVES: To describe the changes in ventilator management over time in patients with neurologic disease at ICU admission and to estimate factors associated with 28-day hospital mortality. DESIGN: Secondary analysis of three prospective, observational, multicenter studies. SETTING: Cohort studies conducted in 2004, 2010, and 2016. PATIENTS: Adult patients who received mechanical ventilation for more than 12 hours. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among the 20,929 patients enrolled, we included 4,152 (20%) mechanically ventilated patients due to different neurologic diseases. Hemorrhagic stroke and brain trauma were the most common pathologies associated with the need fo…
Abnormalities of mitochondrial functioning can partly explain the metabolic disorders encountered in sarcopenic gastrocnemius.
2007
International audience; Aging triggers several abnormalities in muscle glycolytic fibers including increased proteolysis, reactive oxygen species (ROS) production and apoptosis. Since the mitochondria are the main site of substrate oxidation, ROS production and programmed cell death, we tried to know whether the cellular disorders encountered in sarcopenia are due to abnormal mitochondrial functioning. Gastrocnemius mitochondria were extracted from adult (6 months) and aged (21 months) male Wistar rats. Respiration parameters, opening of the permeability transition pore and ROS production, with either glutamate (amino acid metabolism) or pyruvate (glucose metabolism) as a respiration substr…
Impact of Model Shape Mismatch on Reconstruction Quality in Electrical Impedance Tomography
2012
Electrical impedance tomography (EIT) is a low-cost, noninvasive and radiation free medical imaging modality for monitoring ventilation distribution in the lung. Although such information could be invaluable in preventing ventilator-induced lung injury in mechanically ventilated patients, clinical application of EIT is hindered by difficulties in interpreting the resulting images. One source of this difficulty is the frequent use of simple shapes which do not correspond to the anatomy to reconstruct EIT images. The mismatch between the true body shape and the one used for reconstruction is known to introduce errors, which to date have not been properly characterized. In the present study we…
Initiation of high-frequency oscillatory ventilation and its effects upon cerebral circulation in pigs: an experimental study
2006
BACKGROUND: Current practice at high-frequency oscillatory ventilation (HFOV) initiation is a stepwise increase of the constant applied airway pressure to achieve lung recruitment. We hypothesized that HFOV would lead to more adverse cerebral haemodynamics than does pressure controlled ventilation (PCV) in the presence of experimental intracranial hypertension (IH) and acute lung injury (ALI) in pigs with similar mean airway pressure settings. METHODS: In 12 anesthetized pigs (24-27 kg) with IH and ALI, mean airway pressure (P(mean)) was increased (to 20, 25, 30 cm H(2)O every 30 min), either with HFOV or with PCV. The order of the two ventilatory modes (cross-over) was randomized. Mean art…