Studies in Water Balance. 1

Abstract

In certain forms of oedema, particularly those accompanying lipoid nephrosis and certain nutritional states, there is present a marked lowering of the basal metabolic rate. For this reason, it seemed to be desirable to investigate the possible relationship of the total metabolism to water output and to the production of oedema. It has been suggested recently 1 that such a relationship does exist.

A number of investigators 2 - 6 have shown that the ingestion of water increases the metabolism of the organism. In this study, we have endeavored to determine from a quantitative viewpoint, the significance of the oxygen consumption rate in the regulation of the output of water.

A series of 50 normal healthy dogs weighing between 7 and 15 kg. was used in this investigation. The animals were anesthetized with sodium barbital in a dosage of 250 mg. per kilo of body weight, in order to prevent movements which might alter the rate of oxygen consumption. Several control metabolic readings upon trained dogs before and after anesthetization showed that sodium barbital had relatively little effect upon the metabolic rate in the dosage recommended. Moreover, the readings were much more consistent in the anesthetized animal than in the unanesthetized. Fluid was administered by vein and by mouth in the form of 0.9% sodium chloride solution, 5% glucose solution and 10% sucrose solution in amounts varying from 2,000 to 4,000 cc. The rate of oxygen consumption was obtained by means of a Krogh respiratory apparatus, readings of 10-minute duration, taken before, during and after the administration of the standard solutions. The urinary bladder was emptied by catheter before each experiment, and the catheter was retained so that the total urine output during the experimental period was obtained.