Search results for "Hypoxemia"

Metabolic effects of hypoxia and sleep at high altitude(5050)

2010

Noninvasive Ventilation in Critically Ill Patients

2015

Since its first application in the late 1980s, noninvasive ventilation (NIV) has been the first-line intervention for certain forms of acute respiratory failure. NIV may be delivered through the patient's mouth, nose, or both using noninvasive intermittent positive pressure ventilation or continuous positive airway pressure. When applied appropriately, NIV may reduce morbidity and mortality and may avert iatrogenic complications and infections associated with invasive mechanical ventilation. This article provides physicians and respiratory therapists with a comprehensive, practical guideline for using NIV in critical care. © 2015 Elsevier Inc.

Hypoxemia during Sleep

1988

In most normal subjects arterial oxyhemoglobin saturation (SaO2) remains substantially stable throughout all sleep time: some exceptions however, may be observed especially in elderly subjects, who may show desaturations, sometimes associated with apneas (Block et al., 1979; Krieger et al., 1983; Catterall et al., 1985). Conversely, SaO2 drops during part of, or even the whole sleep time, are a common finding in pathological conditions like obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD).

Muscle Oxygen Delivery in the Forearm and in the Vastus Lateralis Muscles in Response to Resistance Exercise: A Comparison Between Nepalese Porters a…

2020

Altitude ascending represents an intriguing experimental model reproducing physiological and pathophysiological conditions sharing hypoxemia as the denominator. The aim of the present study was to investigate fractional oxygen extraction and blood dynamics in response to hypobaric hypoxia and to acute resistance exercises, taking into account several factors including different ethnic origin and muscle groups. As part of the “Kanchenjunga Exploration & Physiology” project, six Italian trekkers and six Nepalese porters took part in a high altitude trek in the Himalayas. The measurements were carried out at low (1,450 m) and high altitude (HA; 4,780 m). Near-infrared spectroscopy (NIRS)-d…

Predictors of mortality and early detection strategies for hepatopulmonary syndrome in liver transplant patients☆

2016

Introduction: Hepatopulmonary syndrome (HPS) is a serious, progressive disease. Its pathophysiology resides in a hypoxic intrapulmonary shunt and severe clinical deterioration. Liver transplantation (LT) is the only effective treatment in appropriately selected patients. Objective: To acknowledge the importance of early diagnosis of HPS. Patients and methods: Observational, descriptive, retrospective trial including 8 patients with HPS that received LT between April 2006 and August 2014. The clinical data prior to transplantation and follow-up after the procedure were reviewed. A multivariate analysis (stepwise forward logistic regression analysis) was used to identify the variable that cou…

Patent Foramen Ovale and Thromboembolic Complications

2010

The foramen ovale, an atrial septal defect which is essential in the fetal circulation, remains patent through adulthood in approximately 25% of the general population and so it represents the most common persistent abnormality of fetal origin. Patent foramen ovale (PFO) allows interatrial right-to-left blood shunting during those periods of the cardiac cycle in which the right atrial pressure exceeds the left one. An increasing number of pathological manifestations of PFO has been recently identified; among these, paradoxical systemic embolism, refractory hypoxemia in patients with right ventricular myocardium infarction or severe pulmonary disease, orthostatic oxygen desaturation in the r…

Normal Values of Oxygen Concentration in Human Blood

1984

Under physiological conditions, the oxygen supply as the product of O2-concentration (mlO2/dl; %(v/v)) and perfusion is influenced by many factors (cf. Fig. 1): perfusion on one hand, oxygen partial pressure (pO2; mmHg), haemoglobin (Hb) concentration (g/dl) and O2 binding power of Hb on the other hand. Under pathological conditions, oxygen supply disturbances are related to hypoxemia, i.e. reduction of O2-concentration in the blood. The differential diagnosis of hypoxemia includes normoxic, hypoxic and circulatoric disturbances of oxygen supply (cf. Fig. 1). Thus it is necessary to describe a NORMOXIC HYPOXEMIA (anemic or toxemic), a HYPOXIC HYPOXEMIA (decreased O2-concentration caused by …

Obstructive sleep apnoea syndrome: What the anesthesiologist should know

2016

Obstructive sleep apnoea syndrome (OSAS) is a rather common sleep disorder and constitutes a risk or an aggravating factor for various underlying diseases. OSAS is characterised by repeated upper airway collapse during sleep causing fragmented sleep, hypoxemia and hypercapnia. It may also cause considerable changes in intrathoracic pressure and an increase in sympathetic nervous activity, which represent the basis of associated pathologies such as arterial hypertension, ischaemic heart disease, diabetes mellitus, stroke and sudden death [1]. Moreover, there is a well-established association between OSAS and postoperative complications [2, 3]. Nevertheless, a significant proportion of patien…

Sleep disordered breathing in patients with cardiovascular comorbidities hospitalized for pulmonary disease

2015

Sleep disordered breathing (SDB) is often overlooked in hospitalized patients. We screened consecutive patients with cardiovascular (CV) comorbidities hospitalized for respiratory problems to study SDB prevalence and type. Patients did not refer typical clinical signs of SDB. Patients (n=34, 21 M, mean age±SD 71±12 yr, BMI: 31.9±5.8 kg/m2) were studied by polygraphy (SomnoLab, Weinmann, Germany) 4.5±3.2 days after admission for COPD exacerbation (COPD-E, n=20), pleural effusion (n=2), asthma exacerbation (n=2) or other causes (n=10). On admission, 18 patients showed respiratory failure (RF, hypoxemic: n=9, hypercapnic: n=9). CV comorbidities (1.7±0.8/patient) were: hypertension (n= 27), hea…

Managing Persistent Hypoxemia: what is new?

2017

Mechanical ventilation is the standard life-support technique for patients with severe acute respiratory failure. However, some patients develop persistent and refractory hypoxemia because their lungs are so severely damaged that they are unable to respond to the application of high inspired oxygen concentration and high levels of positive end-expiratory pressure. In this article, we review current knowledge on managing persistent hypoxemia in patients with injured lungs.