Herrmann L. Blumgart

THE EFFECT OF THE DIGITALIS BODIES ON THE VELOCITY OF BLOOD FLOW THROUGH THE LUNGS AND ON OTHER ASPECTS OF THE CIRCULATION. A STUDY OF NORMAL SUBJECTS AND PATIENTS WITH CARDIOVASCULAR DISEASE

SOF HISTORIES AND PHYSICAL EXAMINATIONS OF PATIENTS

The velocity of venous blood to the right heart in man.

Our previous studies have shown the feasibility of measuring the velocity of blood flow in health and disease by injecting the active deposit of radium into one of the antecubital veins, and determining the time of arrival of the active deposit in the arterial vessels about the elbow of the other arm. The path of the active deposit coursing through the body necessarily included the veins of the arm, the pulmonary circulation, and the artery of the other arm. The velocity measured was a somewhat complex expression, therefore, of the peripheral as well as of the central blood flow. This report deals with an attempt to determine the separate velocities along these paths. A detecting device was placed in a lead block. This block had a hole 5 cm. in diameter bored through its center. The radiations of radium C as it was injected into the veins and as it flowed towards the right heart could not penetrate the lead block and could therefore set up no disturbance in the detecting device. The hole of the lead block with the detector set into it, was placed over the right heart. When the active deposit reached the right heart, the emergent radiations easily traversed the air and tissues between the right heart and the detector, and set up characteristic disturbances in the detecting device. These disturbances were amplified by three electrode vacuum tubes, and were finally registered automatically by a recording pen galvanometer. Knowing the time of injection of the active deposit and knowing the time of its arrival into the right heart, we have a measure of the velocity of the venous blood flow. Figure I is the record of a typical determination.