Renal Water Excretion in Premature

It is generally believed that, after water ingestion, the young infant can neither dilute his urine nor increase the rate of urine flow as rapidly or as effectively as the adult (1-4). Although several sound investigations (4-6) have demonstrated that the kidneys of newborn animals are relatively inefficient in this regard, there have been very few direct observations on these important functions in infants. The present investigation was undertaken, therefore, to compare the renal response of the young premature infant with that of the older infant and adult to ingestion of water.