CORRECTING ARTERIAL HYPOXEMIA BY OXYGEN THERAPY IN PATIENTS WITH ACUTE MYOCARDIAL INFARCTION - EFFECT ON VENTILATION AND HEMODYNAMICS

Hypoxemia and alveolar hyperventilation were common findings in acute myocardial infarction; they were most severe in patients with left ventricular failure or shock. Hyperventilation did not appear to be due to hypoxemia and was not abolished by administration of oxygen. Oxygen administration did not increase tissue oxygen transport in patients with arterial oxygen saturations of 90 per cent or greater because of reductions in cardiac output in excess of increases in oxygen content. Peripheral vascular resistance was increased, and heart rate, blood pressure and left ventricular minute work were unchanged. In patients with arterial oxygen saturations of less than 90 per cent, oxygen administration increased cardiac output, oxygen content and tissue oxygen transport; it had a variable effect on peripheral vascular resistance. © 1969.