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Intermittent hypoxia refers to the discontinuous use of low oxygen levels in normobaric environment. These conditions can be reproduced in hypoxic tents or chambers while the individual is training in different physical activity protocols. Intermittent hypoxia can affect several body systems, impacting nutrition, physical performance, health status and body composition. Therefore, it is necessary to assess protocols, regarding time and frequency of exposure, passive exposure or training in hypoxia, and the simulated altitude. At the molecular level, the hypoxia-inducible factor-1α is the primary factor mediating induction of target genes, including vascular endothelial growth factor and erythropoietin. The goal of these molecular changes is to preserve oxygen supply for cardiac and neuronal function. In addition, hypoxia produces a sympathetic adrenal activation that can increase the resting metabolic rate. Altogether, these changes are instrumental in protocols designed to improve physical performance as well as functional parameters for certain pathological disorders. In addition, nutrition must adapt to the increased energy expenditure. In this last context, performing physical activity in intermittent hypoxia improves insulin sensitivity by increasing the presence of the glucose transporter GLUT-4 in muscle membranes. These changes could also be relevant for obesity and type 2 diabetes treatment. Also, the anorectic effect of intermittent hypoxia modulates serotonin and circulating leptin levels, which may contribute to regulate food intake and favor body weight adaptation for optimal sport performance and health. All these actions suggest that intermittent hypoxia can be a very effective tool in sports training as well as in certain clinical protocols. [ABSTRACT FROM AUTHOR]

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To investigate changes of MMP-9 in the rat spleen and hypoxia-induced microvascular basement membrane under high altitude hypoxia. Thirty male specific pathogen-free Sprague Dawley rats were randomly divided into control and hypoxia groups, with 15 rats in each group. The rats in the control group were placed in Dingxi City, Gansu Province (2080 m above sea level) for 30 days. Rats in the hypoxia group were raised in a hypoxic environment in Maduo County, Qinghai Province (4300 m above sea level), for 30 days to establish a hypoxic rat model. Routine blood tests, MMP-9 mRNA, MMP-9 protein, and the spleen microvascular basement membrane were detected. (1) Compared with the control group, the red blood cell count, hemoglobin, and hematocrit levels of the rats in the hypoxia group were all increased; thus, a hypoxia model was successfully established. (2) Compared with the control group, the expression of MMP-9 mRNA and protein was significantly higher in the spleen of rats in the hypoxic group, and the difference was statistically significant (P <0.05). (3) Compared with the control group, the blood vessel basement membrane in the spleen of the hypoxia group was degraded. Under natural low air pressure and high altitude conditions, the expression of MMP-9 in rat spleen tissue increases and participates in the degradation of the microvascular basement membrane. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ciencias de la Salud is the property of Colegio Mayor de Nuestra Senora del Rosario and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hypoxia-induced factor 1 (HIF-1) plays a fundamental role in the response to low oxygen tension, since it regulates the expression of a wide variety of genes, whose products participate in processes such as angiogenesis, energy metabolism, erythropoiesis, and cell proliferation as well as in the process of neurogenesis, which involves various stages, such as proliferation of neuronal stem cells, migration, differentiation, survival of new neurons, and integration of the same. Among the many intrinsic and extrinsic molecular signals that regulate the production of new neurons from progenitor cells in the adult in the central nervous system (CNS), hypoxic damage plays an important role in the maintenance and function of stem cells in development and disease. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Prescrição e Fisiologia do Exercício is the property of Instituto Brasileiro de Pesquisa e Ensino em Fisiologia do Exercicio and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: COVID-19 disease generates acute respiratory distress syndrome, affects the need for oxygenation and demands nursing care to maintain hemodynamic stability and to prevent respiratory complications. Objective: To analyze the scientific evidence on nursing care facing the need for oxygenation in hospitalized adults with COVID-19 disease. Methods: Integrative review of a universe of 518 scientific articles published from 2020 to 2021 in the following databases: PubMed, EBSCO, CUIDEN and ScienceDirect. N=6 studies were analyzed. These address what the nursing care implies facing the need for oxygenation in adults with COVID-19. Results: Nursing care includes oxygen therapy strategies, recommendations on care in the first line of care, use of high-flow oxygen, early awake prone positioning, control of saturation and vital signs, through a nursing care process. Conclusion: Nursing care satisfies the need for oxygenation through oxygen therapy interventions, control of comorbidities and prevention of hospital risks. [ABSTRACT FROM AUTHOR]

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Copyright of Revista Brasileira de Prescrição e Fisiologia do Exercício is the property of Instituto Brasileiro de Pesquisa e Ensino em Fisiologia do Exercicio and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Albeit massive fish mortality has an extraordinary visual impact and is certainly a fatality, we still have rudimentary understanding on how addressing this problem in the Neotropical region. The processes that lead to fish die-off events are complex and sometimes ephemeral, which can lead to incorrect diagnosis. In this review, we discuss these events in Neotropical freshwaters, both in areas impacted by dams and natural environment, with a focus on deaths mediated by the lack of oxygen (anoxia) or the excess of dissolved gases (gas supersaturation). We examine the available knowledge about the related mechanisms, lethal thresholds for dissolved oxygen (DO) and total dissolved gases (TDG) for fish, and the sequelae of gas bubble disease (GBD). An assessment of the main mortality events in Brazil in the last 10 years is also presented, as well as the best practices for monitoring, prevention, and mitigation. Finally, it is concluded that the proliferation of hydroelectric plants in the Neotropical region might contribute to the expansion of these events and, consequently, increasing of impacts on fish conservation. We consider urgent the inclusion of this topic in the licensing processes for new hydropower projects by the environmental agencies. [ABSTRACT FROM AUTHOR]

Copyright of Revista Latinoamericana de Hipertension is the property of Revista Latinoamericana de Hipertension and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arquivos de Neuro-Psiquiatria is the property of Thieme Medical Publishing Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Colombiana de Ciencias Hortícolas is the property of Revista Colombiana de Ciencias Horticolas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cientifica is the property of Fundacao de Apoio a Pesquisa e Extensao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Medicina do Esporte is the property of Redprint Editora Ltda. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of hypoxia on cognitive processes is an undisputed finding but its extent remains difficult to predict in each particular circumstance. The present study examined the impact of hypoxia on information integration capacities in daily life settings. A sample of 14 students was presented with a series of cards depicting an object a) having a given volume and made of a given substance, and asked to infer its mass;or b) having a given mass and density, and asked to infer its volume; or c) having a given volume and mass, and asked to infer its density. There were three levels of hypoxia situations. In a baseline situation, participants were instructed to put a mask connected with an AltiTrainer (equipment that regulates the oxygen partial pressure provided through the mask) and to perform the three judgment tasks in close succession. The two other situations were similar to the baseline situation except that the AltiTrainer was configured to simulate altitude levels either 1100 m or 3100 m higher than the one in the baseline situation. Contrary to our expectations, no difference in performance was found between the three experimental situations. People's information integration capacities are not affected by hypoxia, even if acclimatization to it has not taken place, and as far as it is not too severe. [ABSTRACT FROM AUTHOR]

Objective: To compare two endotracheal suctioning protocols according to morbidity, days of mechanical ventilation, length of stay in the Pediatric Intensive Care Unit (PICU), incidence of Ventilator-Associated Pneumonia (VAP) and mortality. Methods: A Pragmatic randomized controlled trial performed at University Hospital Pablo Tobón Uribe, Medellin-Colombia. Fortyfive children underwent an as-needed endotracheal suctioning protocol and forty five underwent a routine endotracheal suctioning protocol. Composite primary end point was the presence of hypoxemia, arrhythmias, accidental extubation and heart arrest. A logistic function trough generalized estimating equations (GEE) were used to calculate the Relative Risk for the main outcome. Results: Characteristics of patients were similar between groups. The composite primary end point was found in 22 (47%) of intervention group and 25 (55%) children of control group (RR= 0.84; 95% CI: 0.56-1.25), as well in 35 (5.8%) of 606 endotracheal suctioning performed to intervention group and 48(7.4%) of 649 performed to control group (OR= 0.80; 95% CI: 0.5-1.3). Conclusions: There were no differences between an as-needed and a routine endotracheal suctioning protocol. [ABSTRACT FROM AUTHOR]

Objetivo. Evaluar el signo del " cabeceo" como indicador de hipoxemia en ninos con neumonia. Material y metodos. Se estudiaron 62 menores de 5 anos de edad. Se definio hipoxemia a la saturacion de oxigeno Objective. To assess the clinical usefulness of the head nodding sign (HN) in children with pneumonia. Material and Methods. Cross-sectional study that included 62 children aged 2-59 months. Hypoxemia was defined as arterial oxygen saturation

Copyright of RICYDE. Revista Internacional de Ciencias del Deporte is the property of Revista Internacional de Ciencias del Deporte and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study was carried out at two different altitudes in the southern region of Saudi Arabia: Abha, 2,800 meters above sea level, the high altitude (HA) area and Jazan, 40 meters above sea level the low altitude (LA) area. Following exposure to high altitude, and up to the third week of postnatal development, some of the seminiferous tubules showed detachment from the basal lamina, spaces of different sizes within the epithelial layer with vacuoles in the center and Pyknotic nuclei were noted in the spermatogonia and primordial germ cells. Rounded spermatids were seen in the lumen only on day 35 of hypoxic group, no spermatozoa were recognized until day 45 of postnatal development. On day 45 hypoxic rat testes revealed various types of atrophy and degeneration in the seminiferous tubules and in the interstitial tissue, there was detachment of the basal laminae of the tubules and a profound decrease in cellularity. Significant decrease in epithelial height was noticed in these animals (P <0.05). Also, the diameter of the tubules showed slight decrease with concomitant increase in interstitial spaces in all hypoxic rats. [ABSTRACT FROM AUTHOR]

Objectives. To determine the normal values of arterial blood gases in clinically healthy adults living at 3,350 meters of altitude. Materials and methods. The study was conducted in the Santiago district of Cusco, Peru at 3,350 meters of altitude with a sample of 118 subjects determined in a previous pilot study and selected by convenience sampling. The sample included individuals between 20-59 years old with no pulmonary, cardiovascular and hematological medical history, who practice sports less than 60 minutes per day, non smoking, have resided at least 5 years prior to the study in Cusco and were characterized through clinical examination by two internists and pulmonologists as "clinically healthy". The arterial blood gas collection was standardized for statistical analysis measures of central tendency and dispersion. Student's t-tests and analysis of variance, linear correlation and multiple linear regression were applied. Results. Women comprised 57.6% of the sample. Respiratory rate averaged 16.2 per minute and BMI 24.8. The blood gas results were: pH 7.42 mEq/L; pO2 61.08 mm Hg; pCO2 30.62 mm Hg; pAO2 62.52 mm Hg; SO2 91.13%; AaDO2 0.0 mm Hg; Hto 44.22%; Hb 14.74 mg/dL; CaO2 18.18 vol%; HCO3 19.74 mmol/L; pO2/FiO2 290.79 and Anion Gap 20.99. Using linear regression, it was observed that each year from the age of 20, there was a decrease in pO2 (0.122 mm Hg), pAO2 (0.08 mm Hg), SO2 (0.05%), index pO2/FiO2 (0.571 mm Hg) and an increase in pCO2 (0.056 mm Hg). Conclusions. The results found with respect to blood gases in this population are different from those residing at sea level and can be used to study other populations residing at a similar altitude. [ABSTRACT FROM AUTHOR]

The article discusses a study that assesses the inter-annual effects of hypoxia on the population of A. porosus inhabiting the soft-bottom benthos in Coliumo Bay, Chile. It evaluates the inter-annual dynamics of density and biomass, identifies the inter-annual recruitment dymanics and discusses the results within the context of an Allee effect and its ecological implications. Dead and dying fish were gathered from Coliumo Bay on January 3, 2008 and 396 individuals of A. porosus were sampled from a sandy, rocky intertidal zone fronting Villarrica Cove, Dichato in Coliumo Bay. It suggests the possibility that after the natural hypoxic event, the abundance of A. porosus within the bay shifted towards a low or unstable condition thus increasing the spatial segregation of individuals.

Copyright of Revista de Investigaciones Veterinarias del Peru is the property of Universidad Nacional Mayor de San Marcos (UNMSM) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective. To assess the clinical usefulness of the head nodding sign (HN) in children with pneumonia. Material and Methods. Cross-sectional study that included 62 children aged 2-59 months. Hypoxemia was defined as arterial oxygen saturation <94% measured by pulse oximetry. HN was examined with regard to three levels of hypoxemia (<94%, ≤ 90%, ≤ 84%). Results. The overall prevalence of hypoxemia was 56.5 %. HN was observed in 64.5% (40) of the patients, 48.4% (30) of those had pneumonia and 73.1% were hypoxemic. HN showed a sensitivity of 73.2% and a specificity of 52.4%. Accuracy of HN was better when a cut off level <94% was used. HN in infants was a better index for hypoxemia than for older children. Conclusions. HN was a good predictor of hypoxemia in children with pneumonia. It seems that HN is an easily recognizable sign, and it could be easily taught to parents and health workers. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: Discuss the effects of altitude exposure on neuropsychological functions. Methods: We have conducted a literature review using a source indexed articles at Pubmed in the period from 1921 to 2008, using the following key words: "cognition and hypoxia", "hypoxia and neuropsychology", "acute hypoxia", "chronic hypoxia", and "acclimatization and hypoxia", as well as specific books on the subject. Discussions: Acute and chronic effects of Hypoxia can alter many of the neuropsychological functions in different altitudes due to physiological changes resulted by the oxygen (02) partial decrease that can lead to neuropsychological alterations in individuals exposed to high altitudes. Conclusion: Individuals exposed to high altitudes must use an O2 supplementation and the practice of acclimatization, among other strategy ways that can be used in order to minimize the negative effects of hypoxia on neuropsychological aspects. [ABSTRACT FROM AUTHOR]

The physiological answer of the human body under pressure such as the one generated by flying, where numerous stimuli act simultaneously upon the pilot, has begun being studied and researched since the beginning of 1918. Meanwhile, the studies have proved crucial in enhancing the flight security, in the limitations of the accidents through a better adjustment capacity, a timely intervention of the body to compensate the effects generated by the variations of the atmospheric pressure, of temperature, of the body oxygen level and of the effects caused by accelerations, vestibular and visual illusions. The study is meant, on the one hand, to point out to what degree hypoxia and hypobarism affect the function of the correct body oxygen intake, that is its implications at the mental status level and the pilot's capacity of taking the right decision during the flight, and on the other hand, the explanation in terms of statistics of the measured experimental data. [ABSTRACT FROM AUTHOR]

Copyright of Revista Portuguesa de Ciências do Desporto is the property of Universidade do Porto, Faculdade de Desporto and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Physical activity conduces to oxidative stress, which produces undesirable effects. However, it is well known that free radicals, when present in low concentrations, also have physiological effects in the exercise adaptation process. In addition, the majority of antioxidant supplementation studies, in spite of the fact of decreases oxidative stress, have failed to show a performance improving. Objectives: The goals of this review are to reinterpret the available evidence about the role of free radicals in exercise, and to analyze why antioxidant supplementation have not shown the expectable ergogenic effect. Methods: The following topics were reviewed: i) the free radical biology; ii) antioxidant systems; iii) exercise induced-oxidative stress; iv) oxidative stress and physical performance; and v) antioxidant supplementation and physical performance. Results: There is evidence that physical exercise is associated with excessive free radical production. Deleterious effects of free radicals in physical performance have been shown by in situ studies, although evidence in humans is also available. Physical exercise results in muscular hypoxia, which conduces to adaptative responses, probably through free radical-mediated HIF-1α stabilization. Moreover, a certain level of free radicals is necessary for optimal muscle contractility. Conclusions: Free radicals are necessary for exercise-induced hypoxia adaptation and muscle contraction, for that reason long term antioxidant supplementation interfere with its physiological role. This, explain why antioxidants decrease oxidative stress markers but fail to improve physical performance. [ABSTRACT FROM AUTHOR]

Asthma is a chronic airway inflammatory disease that is associated with pulmonary remodelling of respiratory tissue. During asthma, lung structure changes due to persistent inflammation and causes obstruction of the air flow, which leads to a paradoxical hypoxic condition in the affected pulmonary tissue. Angiogenesis, which is one of the main components of the remodelling process, is mainly regulated by the vascular endothelial growth factor (VEGF), although other less influential factors are also involved. It is known that VEGF is up-regulated by hypoxia inducible factor 1 (HIF-1) during hypoxia. The transcription factor HIF-1 is a dimeric protein composed of two subunits: HIF-1α (inducible by hypoxia) and HIF-1β (constitutive). HIF-1 activates the transcription of genes during hypoxia by translocating to the nucleus and binding to hypoxia response elements (HREs) on the promoter regions of target genes. Recently the expression of HIF has been documented during angiogenesis in lung remodelling during asthma, thus suggesting that it may play a role in this process. The objective of this review is to give to the reader an overview of the literature in hypoxia and its role in remodelling and the pathogenesis of asthma. [ABSTRACT FROM AUTHOR]

Copyright of Revista Española de Cardiología (18855857) is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Snow avalanche case reports have documented the survival of skiers apparently without permanent hypoxic sequelae, after prolonged complete burial despite there being only a small air pocket on extrication. We investigated the underlying pathophysiological changes in a prospective, randomised 2×2 crossover study in 12 volunteers (28 tests) breathing into an artificial air pocket (1- or 2-l volume) in snow. Peripheral SpO2, ETCO2, arterialised capillary blood variables, air pocket O2 and CO2, snow density, and snow conditions at the inner surface of the air pocket were determined. SpO2 decreased from a median of 99% (93–100%) to 88% (71–94%; P<0.001) within 4 min of breathing into the air pocket; the reduction was greater at 1 l, than 2 l, volume air pocket (P=0.013, intention to treat P=0.003) and correlated to snow density (r=0.50, P=0.021, partial correlation coefficient). ETCO2 rose simultaneously from median 5.07 kPa (3.47–6.93 kPa) to 6.8 kPa (5.87–8.27 kPa; P<0.001), with consequent respiratory acidosis. Despite premature interruption due to hypoxia (SpO2≤75%) in 17 of 28 tests (61%), a respiratory steady state prevailed in five tests until protocol completion (30 min). We conclude that the degree of hypoxia following avalanche burial is dependent on air pocket volume, snow density and unknown individual personal characteristics, yet long-term survival is possible with only a small air pocket. Hence, the definition of an air pocket, “any space surrounding mouth and nose with the proviso of free air passages” is validated as the main criterion for triage and management of avalanche victims. Our experimental model will facilitate evaluating the interrelation between volume and inner surface area of an air pocket for survival of avalanche victims, whilst the present findings have laid the basis for future investigation of possible interactions between hypoxia, hypercapnia, and hypothermia (triple H syndrome) in snow burial. [Copyright &y& Elsevier]

Oxygen deficiency during critical illness may cause profound changes in cellular metabolism and subsequent tissue and organ dysfunction. Clinical treatment in these cases targets rapid reoxygenation to avoid a prolonged impaired synthesis of cellular high-energy phosphates (ATP). However, the effect of this therapeutic intervention on tissue metabolism has not been determined yet. Thus the present study was designed to determine the effects of hypoxia and reoxygenation with either room air or 100% oxygen on variables of interstitial metabolism in different tissues using in vivo microdialysis. Twenty-seven adult, male CD-rats (407–487 g; Ivanovas, Kisslegg, Germany) were studied during general anesthesia. Following preparation and randomization, rats were normoventilated for 45 min (FiO2 0.21), followed by induction of hypoxia (FiO2 0.1, 40 min) and reoxygenated for 50 min either with FiO2 1.0 (group 1, n=10) or FiO2 0.21 (group 2, n=10). Control animals (n=7) were ventilated with 21% oxygen during the observation period. Additional to invasive haemodynamic parameters, biochemical tissue monitoring was performed using CMA 20 microdialysis probes, inserted into muscle, subcutaneous space, liver, and the peritoneal cavity allowing analyses of lactate and pyruvate at short intervals. Hypoxia induced a significant reduction in mean arterial pressure (MAP) in group 1 and 2 compared with the control group (P<0.05) without any significant differences between both treatment groups. This was accompanied by a significant increase in blood lactate (10.5±3.1 mM (group 1) and 12.3±4.1 mM (group 2) vs. 1.5±0.3 mM (control); P<0.05) and severe metabolic acidosis (base excess (BE): −18.3±5 mM (1) and −17.3±7 mM (2) vs. −2.6±1.8 mM (control), P<0.05). During hypoxia, the interstitital lacate/pyruvate ratio in groups 1 and 2 increased to 455±199% (muscle), 468±148% (intraperitoneal), 770±218% (hepatic) and 855±432% (subcutaneous) (P<0.05 vs. control, respectively). No significant inter-organ or inter-group differences in interstitial dialysates were observed in the treatment groups, neither during hypoxia nor during reoxygenation. Our data suggest, that hypoxia induces comparable metabolic alterations in various tissues and that reoxygenation with 100% oxygen is not superior to 21% oxygen in restoring tissue metabolism after critical hypoxia. [Copyright &y& Elsevier]