Search results for "HYPOXIA"
showing 10 items of 508 documents
Obesity and Obstructive Sleep Apnea
2021
Obstructive sleep apnea (OSA) is characterized by upper airway collapse during sleep. Chronic intermittent hypoxia, sleep fragmentation, and inflammatory activation are the main pathophysiological mechanisms of OSA. OSA is highly prevalent in obese patients and may contribute to cardiometabolic risk by exerting detrimental effects on adipose tissue metabolism and potentiating the adipose tissue dysfunction typically found in obesity. This chapter will provide an update on: (a) the epidemiological studies linking obesity and OSA; (b) the studies exploring the effects of intermittent hypoxia and sleep fragmentation on the adipose tissue; (c) the effects of OSA treatment with continuous positi…
Combined Epidural and General Anesthesia Prevents Excessive Oxygen Consumption Postoperatively
1994
In the postoperative period patients are at risk of excessive oxygen consumption (VO2). However, patients suffering from cardiovascular disease may be unable to increase their oxygen transport capacity sufficiently and may be especially vulnerable to tissue hypoxia as part of the reaction to intraoperative stress. During the last 10 years contradictory results concerning the benefits of a combined epidural and light general anesthesia have been published. Some of the results indicate that postoperative catabolism maybe depressed and that the neuroendocrine response to stress may be inhibited by such a combined technique1,2. We studied the effect of a combined epidural and light general anes…
Cerebral Blood Flow Regulation Under the Conditions of Arterial Hypoxia
1978
Pronounced arterial hypoxia induces a decrease of cerebrovascular resistance and an increase of total and regional cerebral blood flow. Under the conditions of normal arterial blood pressure and normal acid base status, the changes of both parameters commence when the oxygen tension in the arterial blood decreases below approximately 50 mm Hg. At the same time, the oxygen tension in the cerebral venous blood reaches values below approximately 28 mm Hg. Different authors [23, 28, 30, 31, 33] reported that cerebral blood flow responses to PaO2 decrease are threshold at these oxygen tensions. The threshold oxygen tension of cerebral venous blood was accorded a special significance because Noel…
28 Milrinone is Preferred to Levosimendan for Mesenteric Perfusion in Hypoxia-Reoxygenated Newborn Piglets on Dopamine
2010
28 Milrinone is Preferred to Levosimendan for Mesenteric Perfusion in Hypoxia-Reoxygenated Newborn Piglets on Dopamine
Is a Mask That Covers the Mouth and Nose Free from Undesirable Side Effects in Everyday Use and Free of Potential Hazards?
2021
International journal of environmental research and public health : IJERPH 18(8), 4344 (2021). doi:10.3390/ijerph18084344
Hypoxic burden and angiogenic factors in patients with myocardial infarction and obstructive sleep apnea
2019
Introduction: The amount and severity of hypoxia have been related to risk of cardiovascular events. Aim: To determine the relationship between nocturnal hypoxic burden and pro- angiogenic factors in patients with obstructive sleep apnea (OSA) and myocardial infarction (MI). Method: A prospective, observational study in patients with a first acute MI. Eligible patients underwent a polysomnography within 30 days after MI, and a serum blood sample was drawn in order to measure a panel of angiogenic factors by Luminex technology. A hypoxic burden index (HBI) was calculated as the integral area under the desaturation curve (obtained by calculating the integral of the oxygen saturation reduction…
Anesthetics and Cerebral Protection in Patients Undergoing Carotid Endarterectomy
2015
EREBRAL ISCHEMIA/HYPOXIA may occur in a vari-ety of perioperative circumstances. The main pathophy-siologic aspects involved in cerebral ischemia/reperfusion arecaused by adenosine triphosphate (ATP) consumption, theexcitotoxic actions of glutamate, changes in ionic homeostasis,and formation of free radicals (Fig 1). Outcomes from suchevents range from subclinical neurocognitive deficits to cata-strophic neurologic morbidity or death.
Dilation of the ductus venosus by stent implantation increases placental blood perfusion in fetal sheep.
2006
The reduction of resistance to flow in the ductus venous (DV) and a decrease of blood supply to the liver serve for the survival of the fetus during hypoxia. The present study investigated the influence of the increased diameter of the DV on placental blood perfusion.In 15 ewes with twin pregnancies at gestational ages of 117 +/- 4 days, a stent (4 or 5 mm) was placed into the DV of 1 twin (DV(stent) group) under ultrasound guidance. Blood flow rates in the umbilical vein (UV) and DV of both fetuses were measured using Doppler ultrasound. Eight pairs of twin fetuses were included for the final analysis.The dilatation of the DV increased the blood flow volume rate passed through the DV from …
Usefulness of Cerebral Oximetry in TBI by NIRS
2021
Measurement of cerebral oximetry by near-infrared spectroscopy provides continuous and non-invasive information about the oxygen saturation of haemoglobin in the central nervous system. This is especially important in the case of patients with traumatic brain injuries. Monitoring of cerebral oximetry in these patients could allow for the diagnosis of inadequate cerebral oxygenation caused by disturbances in cerebral blood flow. It could enable identification of episodes of hypoxia and cerebral ischemia. Continuous bedside measurement could facilitate the rapid diagnosis of intracranial bleeding or cerebrovascular autoregulation disorders and accelerate the implementation of treatment. Howev…
Delivery of siHIF‐1α to Reconstruct Tumor Normoxic Microenvironment for Effective Chemotherapeutic and Photodynamic Anticancer Treatments
2021
The tumor hypoxic microenvironment not only induces genetic and epigenetic changes in tumor cells, immature vessels formation for oxygen demand, but also compromises the efficiency of therapeutic interventions. On the other hand, conventional therapeutic approaches which kill tumor cells or destroy tumor blood vessels to block nutrition and oxygen supply usually facilitate even harsher microenvironment. Thus, simultaneously relieving the strained response of tumor cells and blood vessels represents a promising strategy to reverse the adverse tumor hypoxic microenvironment. In the present study, an integrated amphiphilic system (RSCD) is designed based on Angiotensin II receptor blocker cand…