A Pattern of Blood-Volume Responses to Open-Heart Surgery

Abstract

THE maintenance of an adequate circulating blood volume is one of the most important requirements in open-heart surgery. A reduction in the effective circulatory volume results in poor tissue perfusion and enhances the hypoxic metabolic acidosis of cardiopulmonary bypass. The combination of acidosis and hypovolemia may result in irreversible shock. Alternately, hypervolemia is equally hazardous, for a recently wounded and recuperating heart may not be able to cope with the burdens of an excessive circulating volume.The most reliable guide to the estimation of blood volume is its direct measurement. The conventional methods of estimations, such as clinical signs, pressure . . .