Determination of Blood Volume in the Heart and Lungs and the Cardiac Output through the Injection of Radiophosphorus

Abstract

The dilution curve of the specific activity of the erythrocytes in the arterial blood after intravenous injection of labeled erythrocytes with P 32 has been treated mathematically. It is possible with the help of the dilution curve to calculate the minute volume of the heart and the thoracic pool (the residual blood of the heart + the blood content of the lungs). The values of the thoracic pool amount to about 30 per cent of the total circulatory blood-volume.

Left Ventricular Pressures in Patients With Aortic Insufficiency Studied by Intracardiac Catheterization

“…The consistent rise in left ventricular diastolic pressure noted in the seven patients in congestive failure is in keeping with Starling's concept of the failure mechanism: a progressive accumulation of blood within the left ventricular cavity, accompanied by a progressive stretching of the myocardium until a critical point is reached where the muscle fibers offer an increasing resistance to the incoming blood, with a resultant rise in the intracavity diastolic pressure. The elevated diastolic pressure levels we have recorded are likewise in agreement with the demonstration by Nylin and Celander (8) …”

The Disappearance of K 42 from the Nonuniformly Mixed Circulation Pool in Dogs

“…aTLlT , is normalized if we impose the relation (9) This equation serves as a defining relation for a which is a measure of the effect of circulation rate on the movement of label from the circulation.…”

Determination of Circulating Pulmonary Blood Volume in Dogs by an Arteriovenous Dye Equilibration Method

“…3 The slope output method relies upon the assumptions that simultaneous and homogeneous mixing of the injected substance with the pulmonary vascular volume takes place and that loss of dye from the pulmonary bed into the arterial system is an ex-ponential function of the volume of the largest diluting chamber. 4 ' 5 The validity of these assumptions, particularly under abnormal circumstances, has not as yet been firmly established.…”