View clinical trials related to Hypoxia.
Filter by:Transfusion of red blood cells is an everyday practice in critical care with the primary aim of restoring adequate tissue oxygenation. However, blood transfusion may also be harmful and costly, therefore a so called restrictive transfusion regime has been suggested by recent guidelines. These transfusion guidelines consider certain levels of hemoglobin as transfusion trigger, which on its own gives little information if any about the balance between oxygen delivery (DO2) and consumption (VO2). Hence, there is a clear need for additional physiologic transfusion trigger values. One of the potentially useful and easily obtainable physiological parameters is the central venous oxygen saturation (ScvO2), which has been shown to be a potential transfusion trigger value in hemodynamically stable but anemic patients. However, the role of ScvO2 as a transfusion trigger value was examined only in a retrospective observational study and in animal experiment. The normal value of ScvO2 in a resting adult at rest is around 70-75%, which is the product of the VO2 and DO2 relationship. Low ScvO2 usually indicates inadequate DO2. It was found in an observational study that if ScvO2>70% before transfusion due to transfusion only the value of hemoglobin increased but the value of ScvO2 did not change. This finding indicates that the DO2 may have been adequate in spite of the low hemoglobin value and the transfusion may have been unnecessary. In one of their recent animal experiments, the investigators reported that in an isovolemic-anemia model the value of ScvO2<70% was only reached when the value of hemoglobin was far less, 59 g/L, than the recommended lowest value of 70g/L as transfusion trigger by guidelines. Despite the pathophysiological rationale and the encouraging results of retrospective studies and animal experiments, prospective randomized trials in order to test the effects of an ScvO2-assisted transfusion protocol are yet to be performed. The aim of this study is to investigate the effects of an ScvO2-assisted transfusion protocol as compared to the guideline-based, hemoglobin levels guided transfusion practice.
This is a validation study of a near-infrared spectroscopy (NIRS) device designed to measure the cerebral tissue oxygen saturation.
The purpose of this study is to investigate the efficacy and safety of umbilical cord milking in depressed neonates at birth for prevention of hypoxic ischemic encephalopathy.
The aim is to define in detail metabolic pathways at rest and during aerobic exercise in normal and healthy men and women under normobaric normoxic and moderate hypoxic conditions, using metabolomics technologies based on minimally invasive sampling relying on gas chromatography and mass spectrometry.
Few early prognostic indicators are currently available for patients' families and clinicians following out of hospital cardiac arrest (OHCA), and blood biomarkers may be of prognostic value in these cases. Brain tissue is highly dependent upon aerobic respiration, and oxygen deprivation result in irreversible neuronal cell injury. Peptides released into the blood by injured neuronal cells can be measured to estimate degree of injury, and potentially predict long term neurological outcome.
Intrauterine growth restriction (IUGR) is one of the major contributors to perinatal mortality and morbidity and is characterized by complex hemodynamic changes involving placental and fetal arterial, cardiac and venous circulations .However, the temporal sequence of these modifications in relation to other hemodynamic changes of the fetal arterial and venous circulations is unknown. The aim of this study was to evaluate cardiac function and other hemodynamic changes in a group of fetuses with IUGR and clinical impact on perinatal outcome .
The study will aim to describe and evaluate the effect of chronic beetroot juice supplementation on acute mountain sickness symptoms and exercise in a hypoxic environment. It is hypothesized that beetroot supplementation will decrease acute mountain sickness and increase exercise performance.
Background High-flow nasal cannula (NHF) are a promising tool for administering oxygen to critically ill patients with high respiratory demand. Prone positioning (PP) is a simple and cost-effective strategy that since 1980s has been used in mechanically ventilated patients with acute respiratory failure to treat oxygenation impairment. A large randomized study detected a relevant survival benefit by prone positioning in patients with moderate to severe acute respiratory distress syndrome (ARDS) undergoing invasive mechanical ventilation and managed with the ARDS network PEEP-FiO2 table strategy. Theoretically, PP may benefit spontaneous breathing patients too, but data concerning its application in such context are limited to small case series and a retrospective study. The investigators designed a pilot feasibility study to assess the safety and efficacy of prone positioning in acute hypoxemic respiratory failure patients noninvasively treated with NHF. Methods Patients: 15 adult hypoxemic (PaO2/FiO2<200 mmHg with respiratory rate greater than 25 breaths per minute) non-hypercapnic patients with acute respiratory failure. PaO2/FiO2 will be assessed while the patients is receiving 50 L/min of 50% oxygen via a standard face mask for a 15-minute monitoring period at study entry. Protocol Eligible patients will undergo NHF for 1 hour in the supine semi-recumbent position (baseline, BL). Afterwards, each enrolled patient will be placed in the prone position for 2 hours. After a 2-hour PP period, the patient will be rotated and will undergo 1 hour of NHF in the semi recumbent supine position (Supine step). Measurements Patient's demographics will be collected at study entry. At the end of the monitoring period, and then on a hourly basis the following data will be collected: - Respiratory rate, SpO2, pH, PaCO2, PaO2, SaO2, PaO2/FiO2; - Heart Rate, arterial blood pressure; - Dyspnea, as defined by the VAS dyspnoea scale; - Discomfort, as defined by a visual analogic scale (VAS) adapted to rate the procedural pain of ICU patients; - End expiratory lung impedance (EELI), tidal volume distribution, global and regional lung dynamic strain (Change in lung impedence due to tidal volume/ELLI). - Work of breathing, assessed by pressure-time product (PTP) of the esophageal pressure and inspiratory swings in this signal. - Occurrence of pendelluft phenomenon The number of adverse events will be also recorded for each study step.
This is a prospective randomized cross over study of healthy volunteers comparing end-tidal oxygen concentration among subjects undergoing continuous positive airway pressure ventilation via a noninvasive ventilation (NIV) mask with and without the addition of nasal cannulas.
Patients with severe Chronic Obstructive Pulmonary Disease (COPD) and low oxygen levels in the blood are at risk of developing pulmonary hypertension and strain on the right side of the heart, both of which are known to increase symptoms and worsen prognosis It is not fully established whether interval exercise training in patients with severe COPD and concomitant low oxygen levels is beneficial. This study aims to evaluate the effects of aerobic interval exercise training in patients with severe COPD and low oxygen levels in the blood, with a particular emphasis on such effects on the cardiovascular system and pulmonary circulation.