The effects of gas mixtures comprising supplementary 3% carbon dioxide, 35% oxygen or a combination of 3% CO(2) plus 35% O(2) in ambient air have been compared on arterial blood gases, peripheral and cerebral oxygenation and middle cerebral artery velocity (MCAV) at 150 m and on acute exposure to 3459 m in 12 healthy subjects. Breathing 3% CO(2) or 35% O(2) increased arterial blood oxygen at bo...

Studies examining acute oxygenation and perfusion changes in irradiated skin are limited. Hyperspectral imaging (HSI), a method of wide-field, diffuse reflectance spectroscopy, provides noninvasive, quantified measurements of cutaneous oxygenation and perfusion. This study examines whether HSI can assess acute changes in oxygenation and perfusion following irradiation. Skin on both flanks of nu...

Metabolic products of skeletal muscle contraction activate metaboreceptor muscle afferents that reflexively increase sympathetic nerve activity (SNA) targeted to both resting and exercising skeletal muscle. To determine effects of the increased sympathetic vasoconstrictor drive on muscle oxygenation, we measured changes in tissue oxygen stores and mitochondrial cytochrome a,a3 redox state in rh...

OBJECTIVES To evaluate the use of inhaled nitric oxide (NO) in the management of persistent pulmonary hypertension of the newborn. METHODS Computerized bibliographic search on MEDLINE, CURRENT CONTENTS and LILACS covering the period from January 1990 to March 1998; review of references of all papers found on the subject. Only randomized clinical trials evaluating nitric oxide and conventional...

INTRODUCTION Although extracorporeal membrane oxygenation has made sufficient progress to be considered for the management of life-threatening cardiac and respiratory failure, the risk of hemorrhagic complications may outweigh the benefits for patients with bleeding tendencies. We report, to the best of our knowledge, the first case of successful treatment by extracorporeal membrane oxygenation...

INTRODUCTION Anti-neutrophil cytoplasmic antibody positive pulmonary capillaritis complicated by diffuse alveolar hemorrhage is a potentially fatal condition for which extracorporeal membrane oxygenation can facilitate improved outcomes and potential cure. Diffuse alveolar hemorrhage can be the initial presentation of an autoimmune disorder. The management is centered on the use of immunosuppre...

Synaptic transmission initiates a cascade of signal transduction events that couple neuronal activity to local changes in blood flow and oxygenation. Although a number of vasoactive molecules and specific cell types have been implicated, the transformation of stimulus-induced activation of neuronal circuits to hemodynamic changes is still unclear. We use somatosensory stimulation and a suite of...

Five-week-old normotensive Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) were subjected to hyperbaric oxygenation with an enhanced atmospheric pressure (950 mmHg) and an increased oxygen concentration (36%) for 6 h per day. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were monitored for 8 weeks of hyperbaric oxygenation period. After 8 weeks of hyperbaric...

Near-infrared (NIR) spectroscopy is a noninvasive optical technique that is increasingly used to assess muscle oxygenation during exercise with the assumption that the contribution of skin blood flow to the NIR signal is minor or nonexistent. We tested this assumption in humans by monitoring forearm tissue oxygenation during selective cutaneous vasodilation induced by locally applied heat (n = ...

BACKGROUND Pulmonary function is impaired during pneumoperitoneum mainly as a result of atelectasis formation. We studied the effects of 10 cm H2O of positive end-expiratory pressure (PEEP) and PEEP followed by a recruitment maneuver (PEEP+RM) on end-expiratory lung volume (EELV), oxygenation and respiratory mechanics in patients undergoing laparoscopic surgery. METHODS Sixty consecutive adul...