CARDIAC OUTPUT IN MAN

Abstract

CURRENT medical teaching regarding the factors controlling the cardiac output is based mainly on the concepts of animal physiology. When applied to man these concepts have of necessity been rather vague and sketchy. The advent of the foreign gas methods,1and, more recently, the wider use of the ballistocardiograph2and the method of catherization of the right side of the heart3now enable clinicians to investigate the output of the heart by actual measurement. The physician may now add knowledge gained from studies on man to that obtained by the physiologists in laboratory work on animals. With the accumulation of these observations, a reevaluation of the factors controlling the cardiac output in human beings appears to be in order. As might be expected, many factors affecting the cardiac output in man, with his intact nervous and circulatory systems, were not apparent in the conventional heart-lung preparation. The purpose of this paper is to