VENOUS PRESSURE

Thanks to a greatly simplified technic, the measurement of arterial blood pressure has acquired widespread clinical application in recent years. Knowledge regarding venous pressures also may be expected to promote a better understanding of certain quite different features of the circulation. Methods for estimating venous pressure in man have by no means been unknown; but, partly because they were cumbersome and required some technical skill, they failed to attract the attention of physicians. The apparent indifference toward the subject was doubtless augmented by the fact that there has been considerable uncertainty regarding the factors that really affect venous blood pressure. It has been assumed, for example, that changes in vascular tonus sufficient to vary markedly the amount of blood in the peripheral veins might notably alter the venous pressure; but Hooker has demonstrated that the latter is normally independent of peripheral arteriole resistance. This has been confirmed more recently by