Search results for " Oxygenation"

Outcome of extracorporeal membrane oxygenation support for high-risk percutaneous coronary intervention in non-ST-segment elevation acute coronary sy…

2020

Tumor Oxygenation in Anemic Rats: Effects of Erythropoietin Treatment Versus Red Blood Cell Transfusion

1995

Anemia was induced in rats by the development of a hemorrhagic ascites. These animals also bore solid tumors (DS-sarcomas) on the hind foot dorsum. The effects of two methods for anemia correction on oxygenation in the solid tumors were compared in this study. Anemia was corrected either chronically by erythropoietin administration (1000 IU/kg) over 14 days (EPO) or acutely by transfusion with red blood cells (TR). Non-anemic and untreated anemic animals served as controls. Tumor oxygenation was determined in anesthetized animals using polarographic needle electrodes and pO2 histography. The reduction in hematocrit and hemoglobin content found in anemic animals could successfully be correct…

Surgical treatment of pharyngostomes in irradiated patients. Our experience with musculocutaneous pectoralis major flap and hyperbaric oxygen therapy

2005

Surgical treatment of pharyngostomes in irradiated patients. Our experience with musculocutaneous pectoralis major flap and hyperbaric oxygen therapy. Cordova A, Corradino B, Pirrello R, Di Lorenzo S, Dispenza C, Moschella F. Source Dipratimento di Discipline Chirurgiche ed Oncologiche, Divisione di Chirurgia Plastica e Ricostruttiva, Facolta di Medicina, Universita di Palermo, Palermo, Italy. chirplas@unipa.it Abstract CONCLUSION: Our experience confirms that pectoralis major flap is the first-choice technique for repairing recurrent hypopharyngeal fistulae in previously irradiated patients in whom microsurgical techniques are not indicated, and that hyperbaric oxygen therapy helps to solv…

Oxygen-haemoglobin dissociation curve in hypoxic rats of first or second generation.

1993

SUMMARY 1. Albino Wistar rats were raised in a normobaric hypoxic environment (10% O2 in N2). Two generations of hypoxic rats were observed for changes in their haemoglobin-oxygen (Hb-O2) dissociation curves (ODC), 2,3-diphosphoglycerate (2,3-DPG), haemoglobin (Hb), and Hill coefficients at P50 (n50). The first generation were called (H1) and the second generation (H2). The control group (N) had a normoxic environment. 2. Thirty-five rats (13 N rats, 12 H1 rats and 10 H2 rats) were used. The 2,3-DPG was significantly higher in both hypoxic groups when compared with N rats (2.02 ± 0.51 mmol/L) but 2,3-DPG of H2 rats was significantly lower than that of H1 rats (H1 = 3.48±0.58 mmol/L and H2 =…

Outcomes after extracorporeal membrane oxygenation for the treatment of high-risk pulmonary embolism: a multicentre series of 52 cases

2018

International audience; Aims The role of extracorporeal membrane oxygenation (ECMO) remains ill defined in pulmonary embolism (PE). We investigated outcomes in patients with high-risk PE undergoing ECMO according to initial therapeutic strategy. Methods and results From 01 January 2014 to 31 December 2015, 180 patients from 13 Departments in nine centres with high-risk PE were retrospectively included. Among those undergoing ECMO, we compared characteristics and outcomes according to adjunctive treatment strategy (systemic thrombolysis, surgical embolectomy, or no reperfusion therapy). Primary outcome was all-cause 30-day mortality. Secondary outcome was 90-day major bleeding. One hundred a…

Relating Measuring Signals From P O 2 Electrodes to Tissue P O 2: A Theoretical Study

1992

Organ surface P O 2 measurement by oxygen sensitive electrodes has proved to be an efficient tool for monitoring changes in tissue oxygenation status in a number of experimental and clinical situations. A parameter giving more direct information is the P O 2 distribution within tissue cells which, however, can only be assessed by more invasive methods. To date, a quantitative relation between P O 2 electrode measurements and P O 2 in tissue cells has not been established. Part of this problem lies in the fact that any surface electrode P O 2 measurement is not confined to tissue cells but rather represents some average over P O 2 values in a certain volume containing not only tissue cells b…

Pathophysiological approaches to identifying tumor hypoxia in patients

1991

The present report summarizes observations of the authors on tumor oxygenation and on techniques for characterizing tumor hypoxia in patients. Cryospectrophotometric measurements of HbO2 saturations in tumor microvessels allow for estimates of the proportion of well oxygenated tissue regions. Labeling of tissue areas at oxygen (O2) tensions (pO2) less than 10 mm Hg with misonidazole may be used for a general characterization of the oxygenation status in patient tumors rather than for the determination of the radiobiologically hypoxic cell fraction. Quantitative bioluminescence and single photon imaging make it possible to determine ATP concentrations in absolute terms with a spatial resolut…

Inhibition of tumor lactate oxidation: consequences for the tumor microenvironment.

2011

Abstract Background and purpose Tumor cells are recognized as being highly glycolytic. However, recently it was suggested that lactate produced in hypoxic tumor areas may be taken up by the monocarboxylate transporter MCT1 and oxidized in well-oxygenated tumor parts. Furthermore, it was shown that inhibition of lactate oxidation using the MCT1 inhibitor α-cyano-hydroxycinnamate (CHC) can radio-sensitize tumors possibly by forcing a switch from lactate oxidization to glycolysis in oxygenated cells, which in turn improves tumor oxygenation and indirectly kills radio-resistant hypoxic tumor cells from glucose starvation. Material and methods To provide direct evidence for the existence of a ta…

Effects of Recombinant Human Erythropoietin (rHuEPO) on Tumor Control in Patients with Cancer-Induced Anemia

2005

It is well recognized that anemia-induced tumor hypoxia is associated with a reduced sensitivity of tumors to radiation and some forms of chemotherapy. Thus, the correction of lower hemoglobin (Hb) concentrations with recombinant human erythropoietin (rHuEPO) can play an essential role by improving tumor oxygenation. Based on evidence from a number of trials, treatment with rHuEPO will effectively ameliorate anemia and improve quality of life. However, one of the most essential prerequisites for achieving this benefit is the use of rHuEPO in agreement with the evidence-based ASCO/ASH-guidelines recommending a target Hb concentration of 12 g/dl (7.44 mmol/l).

Hypoxia and Aggressive Tumor Phenotype: Implications for Therapy and Prognosis

2008

Abstract Tumor hypoxia, mostly resulting from poor perfusion and anemia, is one of the key factors in inducing the development of cell clones with an aggressive and treatment-resistant phenotype that leads to rapid progression and poor prognosis. Studies in patients with solid tumors suggest that there is a range of hemoglobin (Hb) concentrations that is optimum for tumor oxygenation. When used to achieve an Hb level within this range, erythropoiesis-stimulating agents (ESAs) can be expected to increase tumor oxygenation, and this may favorably influence sensitivity to treatment as well as quality of life. There is no robust evidence that ESAs, when used as indicated, have a negative effect…