RELATION OF BSP RETENTION DURING PROLONGED FASTS TO CHANGES IN PLASMA VOLUME

Obese subjects who fasted or consumed very low calorie diets developed abnormal BSP retention. Sodium loading during fasting tended to raise plasma volumes and effected an improvement in BSP clearance. Conversely, a sodium and water diuresis had the opposite effect. The fasting ketoacidosis seemed unrelated to the change in BSP levels. The phenomenon of the acute rise in BSP retention with fasting may thus be explained by a reduction in hepatic blood flow secondary to a fall in plasma volume and the prompt improvement with refeeding by the reverse mechanism. Parenchymal liver damage need not be invoked as a cause of high BSP levels. These findings suggest that transiently abnormal BSP levels in some acute disease state may reflect the result of hypovolemia. © 1968.