Effect of Digitalis and Rest on Pulmonary and Peripheral Circulation in Patients with Circulatory Failure Caused by Heart Disease

This study was undertaken to shed further light on the mechanism of circulatory failure caused by heart disease and on the circulatory changes that follow administration of large therapeutic doses of digitalis, and rest. Weiss and Ellis 1 observed the effect of digitalis on the volume and velocity of blood flow and other aspects of the circulation after repeated control observations in patients with rheumatic heart disease and with compensated circulation at rest. In this study such repeated control observations on the aspects of the circulation measured, because of the clinical condition of the patients and of the methods used, were not feasible. A definite separation of the changes due to digitalis effect and rest between determinations, therefore, cannot be made, but the arrangement of the observations was similar to those used in the treatment of cardiac patients. To ascertain a possible correlation between the pulmonary circulation and ventilatory function, in some of the cases measurements of different components of the lung volume were also performed simultaneously with the circulatory observations. The following aspects of the circulation were studied simultaneously before and after digitalis: (1) electrocardiogram; (2) the degree of orthopnea; (3) arterial blood pressure; (4) venous pressure with the method of Moritz and Tabora 2 ; (5) cardiac minute volume output with the method of Moore, Kinsman, Hamilton, and Spurling 3 ; (6) the peripheral and pulmonary velocity of the blood flow according to the method of Weiss and Robb 4 ; (7) blood volume according to the method of Keith, Rowntree and Geraghty 5 ; (8) lung volume with the method of Van Slyke and Binger 6 ; (9) oxygen and carbon dioxide content of the blood samples obtained from the femoral artery and vein.