Active clinical trials for "Hypoxia"

A study consisting of a prospective and retrospective cohort in the ICU, ER and pulmonary department in a university hospital in Amsterdam and a teaching hospital in Alkmaar, the Netherlands. The relationship between the oxygen saturation measured by pulse-oximetry and the arterial PaO2 is investigated in order to investigate which transcutaneous saturation values are safe when administering oxygen in relation to hyperopia and hypoxia.

The aim of this study is to investigate the relationship between the patient positioning in the beach chair position with consequential arterial pressure changes and their influence on regional cerebral oxygen saturation under two anesthesia techniques, general anesthesia in one group of patients and interscalene block in the second group of patients.

Colorectal cancer (CRC) is one of the leading causes of cancer mortality in Canada. Rectal cancers are now known to be hypoxic which is a negative prognostic factor and predictive of metastatic spread and poor responsiveness to treatment. This has also been shown in preclinical xenograft models. Hence there is a need for identification of hypoxic rectal cancers. In this pilot study the investigators intend to non-invasively assess the tumor and nodal metastasis using an integrated Positron Emission Tomography-Magnetic Resonance Imaging scanner (PET/MRI) with 18F-Fluoroazomycin Arabinoside (18F-FAZA) a radiopharmaceutical for assessing tumor hypoxia. The hypoxic rectal tumors will show an increased uptake of 18F-FAZA on PET which will have morphological correlation on MRI. The patient will then undergo neoadjuvant chemoradiation therapy (CRT) followed by repeat 18F-FAZA PET/MRI and rectal cancer surgery with pimonidazole staining. Pimonidazole is an extrinsic marker of hypoxia that is selectively reduced and covalently bound to intracellular macromolecules in areas of hypoxia within normal and tumor tissue with current approval for use in humans for research studies. The primary goal of this pilot trial is to validate FAZA-PET as a biomarker of hypoxia by correlating its uptake in rectal tumors to pimonidazole staining in histopathology specimens. If the investigators pilot study successfully demonstrates the uptake and correlation of pimonidazole and FAZA-PET, the investigators would like to initiate a larger study examining hypoxia in rectal cancer. The investigators aims would be to image patients with locally advanced rectal cancer before CRT to ascertain whether high FAZA-PET uptake correlates with poor outcome to CRT. The ability to preoperatively predict the patient sub-population that will respond best to CRT, will help to identify the "complete pathological" responders and avoid unnecessary surgery. Furthermore, the FAZA-PET high subset of patients may benefit from other treatment strategies including clinical trials of anti-hypoxic agents.

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 .

A prospective cohort pilot study of non-cardiac patients to determine the feasibility of recruiting 150 patients to undergo postoperative continuous hemodynamic monitoring for up to 3 days.

The primary objective of this study is to evaluate the % oxygen saturation by pulse oximetry accuracy of a combined pulse oximetry system which consists of a Nonin sensor ), an adaptor cable, and an oximetry system during non-motion conditions.

The imaging of cerebral oxygenation is an extremely important tool in understanding the pathophysiology of the tumor and for adaptation of therapies according to hypoxia. Currently, imaging of cerebral oxygenation is mainly performed by the use of Positron Emission Tomography (PET). Thus, the investigators have been able to show that the FMISO radiotracer can reveal tumor hypoxia (HypOnco study, promotor: Caen University Hospital, main investigator: J.S. Guillamo). After injection of the radiotracer, increased uptake is observed in the regions for which the tissue oxygen pressure is less than 10 mmHg (the healthy brain with a tissue oxygen pressure (ptO2) ≈ 40mmHg). Although PET is a reference methodology, it is not widely practiced mainly because of radioactive sources. Magnetic Resonance Imaging (MRI) would bypass the previously mentioned PET limitations. The investigators have recently shown that a measure of local oxygen saturation could be obtained by MRI. This methodology has also been implemented at a clinical scale on lower field MRI magnets, but its formal validation in a clinical situation remains to be demonstrated with respect to FMISO. The major advantage of this methodology is that MRI is already performed in routine practice for patients. Measuring tissue oxygenation with MRI (SatO2-MRI) would not add additional examination for the patient. In addition, MRI is a non-ionizing methodology with a very good spatial resolution compared to PET, this should help to better understand intratumoral heterogeneity. Similarly, in preclinical studies, the investigators have shown in a context of mild hypoxia that SatO2-MRI may be more sensitive than PET. The investigators propose a study to compare in patients with glial tumors, images obtained by 3 Tesla MRI of SatO2-MRI to the hypoxia maps obtained by FMISO PET. These imaging studies will be confronted with studies carried out in immunohistochemistry on biopsies / resection allowing to reveal and to quantify by image analysis the expression of the factors induced by hypoxia (HIF1, HIF2). This study should include 20 patients with glioma (15 high-grade patients and 5 low-grade patients) in pre-surgery. The aim is to show that SatO2-MRI is a relevant methodology (in terms of sensitivity, specificity) for assessing intratumoral oxygenation in a context of brain tumors. This fits perfectly into an era of personalized medicine where functional imaging finds its meaning.

Present study suggests that excessive occlusal forces did not cause a significant change in hypoxia and vascular markers, however a slight alteration in subgingival microbiota was observed.

Patients and methods: It is a prospective double blind study done on total 300 patients. Admitted with respiratory failure ARDS due to severe lung contusion. All of them selected to be ventilated for one week or more. Patients were randomly allocated in one of three groups each group contain 100 patients. Group A considered control extubated and follow our routine protocol, patients of group B reconnected to mechanical ventilation before extubation for one hour. patients of Group C extubated and immediately connected to NIV with BIPAP mode for 1 hour every 12 hours for 24 hours. Results: There was significant reduction in the number of patients had deterioration in conscious level in all the duration of the study in patients of both groups B and C compared to group A. Also significant reduction in the number of patients had deterioration in clinical parameters of respiration in all the duration of the study in patients of both groups B and C compared to group A as regards high respiratory rate, desaturation and development of hyperdynamic circulation (tachycardia and hypertension). significant reduction in the number of patients had multiple quadrant parenchymatous infiltration in all the duration of the study in patients of both groups B and C compared to group A. significant reduction in the number of patients had marked limitation to FEV1, FVC and MVV in all the duration of the study in patients of both groups B and C compared to group A. Conclusion: Use of either NIV every 12 hours for 24 hours or MV for one hour after fulfillment of weaning criteria reduces reintubation and post-extubation respiratory failure and decrease the ICU stay in critically ill patients with resolving ARDS due to severe lung trauma.

Healthcare systems around the world have been dealing with COVID 19. One of the main manifestations of this infection is lung involvement of varying degrees, causing a spectrum of diseases from mild lower respiratory tract infection to severe Adult Respiratory Distress Syndrome (ARDS). One of the important clinical parameters is to detect hypoxia early in order to initiate a higher level of care at the earliest. The presence of silent or latent hypoxia has made this task difficult in COVID 19. Besides, critical findings such as silent hypoxia that is not at rest but triggered by effort can be revealed by some practical field tests such as the 6-minute walk test or the 1-minute chair sit and stand test. Moreover, these simple tools also help to investigate the patient's readiness for discharge. In this way, it will be useful to evaluate their usability in discharge decisions or in determining the post-discharge cardiopulmonary reserves of the patients and therefore their rehabilitation needs. Although walk and performance tests can be performed naturally, safely and simply, more similarly to movements in daily living activities compared to cardiopulmonary exercise tests, the interest in these tests has increased over the years, especially in subjects such as exercise capacity, mortality and morbidity expectation, or oxygen desaturation in patients with chronic cardiopulmonary pathology. The number of studies in 19 patients is quite limited. For this reason, the necessity of new studies on different field tests to detect the presence of latent hypoxia, which expresses the oxygen desaturation triggered by effort, and to evaluate the exercise tolerance status before discharge, has been emphasized in recent reviews.The aim of this study is to determine the presence of silent hypoxia, which expresses the oxygen desaturation triggered by effort, in Covid-19 patients and to compare the different short-term walk and performance tests, which the investigators consider easier and applicable in the conditions of the pandemic environment, with the classical gold standard test ( Six minute walk test) in order to evaluate the exercise tolerance status of the patients before discharge.