Myocardial function during acute hypoxia in the calf.

摘要: Hemodynamics and myocardial contractility were evaluated in five unanesthetized calves during acute hypocapnic isocapnic hypoxia with beta-adrenergic blockade. Both hypoxia, mean PaO2 levels of 33.1 39.1 mm Hg respectively, produced a decline stroke volume index, while cardiac output index maintained at normoxic control by an increase heart rate. Evaluation indices suggested augmentation left ventricular both hypoxia. Betaadrenergic blockade effectively eliminated the suggesting important role adrenergic nervous system genesis cardiovascular response calf to Right failed demonstrate clear-cut when concurrent afterload was considered. Mean pulmonary arterial blood pressure rose significantly The pressor augmented beta blockade, indicating that autonomic is capable modifying hypoxic this species.