The influence of ether anesthesia on the excretion of nitrogen by dogs

Abstract

A series of nine experiments were made upon four dogs, the experiments ranging in length from 7 to 17 days. The plan followed was to get the animals into a condition of nitrogen equilibrium, then to induce ether anesthesia continuously for periods varying from ½ hour to 4 ½ hours. The initial influence of the ether was to cause an increased excretion of nitrogen, the average daily percentage increase varying from 6.5 per cent. after 30 minutes anesthesia to 43.5 per cent. after 3 hours narcosis. In the latter case the animal had been anesthetized on each of the two preceding days and therefore this large increase may represent the cumulative effect of the anesthesia. In six of the nine experiments the average daily excretion of nitrogen continued above normal during the entire experimental time after anesthesia was induced, the ultimate average daily increase varying from 3.5 per cent. for a 5-day period following 2 hours anesthesia to 17.5 per cent. for a 14-day period after ether narcosis had been induced for periods of 1, 2 and 3 hours on 3 successive days. In the three experiments which showed a diminished excretion of nitrogen after anesthesia the normal output of nitrogen was decreased 1.5 per cent., 1.8 per cent., and 4.0 per cent. as the result of anesthesia periods of ½ hour, 4 ½ hours and 1 hour respectively.

In each experiment the anesthetic had a diuretic effect, the extent of the diuresis varying from an initial average daily increase of 5.7 per cent. in the volume of urine after ½ hour of anesthesia to an increase of 24.8 per cent. after an anesthesia period of 4½ hours. The diuretic effect continued until the close of the experiment in every instance except one, the average daily percentage increase in the urine volume for the entire experimental time ranging from 3.1 per cent. for 7 days after 4½ hours anesthesia to 20.7 per cent. for 7 days after 2 hours anesthesia.