The Velocity of Blood Flow in Part of the Pulmonary Circulation

Abstract

It is possible to time the velocity of the blood current in man, starting, for example, from the median basilic vein in the elbow and ending at the alveoli of the lungs. The intervening distance may be considered as a constant circuit, part of the pulmonary circulation. The time needed for blood to traverse this intervening distance was carefully noted in conditions of health and disease. This report, based on studies in man, describes the technique of the method employed, results obtained by this method, and its application in physiological and clinical problems.

The subject is recumbent in bed. His mouth having been freely rinsed with tap water, directly before the test, he is instructed to breathe rapidly, about 40 excursions per minute, and to hold his mouth wide open. At ordinary room temperature (70° to 72°F.) and under usual atmospheric conditions (753 mm. Hg.) a measured quantity of a non-toxic substance possessing an odor easily identified is quickly injected, within one second, into the right or left median basilic vein at the elbow and the arrival of the odor in the subject's breath instantly noted. The time required for the odor to complete this circuit is carefully clocked.

For intravenous injections the following substances have been utilized: guaiacol, sodium cacodylate, allyl sulphide, methyl salicylate, ether, and perfumes, more especially ingredients in the preparation of jasmin perfume, benzyl acetate and linalyl acetate. The sharpest results are obtained with perfume and ether. Our earliest use of ether, October, 1932, was suggested by the work of Burkhardt, Kümmell, and Küttner, 1 , 2 , 3 who published results on the intravenous administration of ether as an anesthetic and commented on the prompt appearance of ether in the breath.