Anesthesia induced by barbituric acid derivatives with special reference to associated blood sugar changes.

Abstract

During an attempt to study the regulatory influence of the central nervous system on the carbohydrate metabolism, it was noted that cats under the effect of iso-amyl-ethyl barbituric acid (amytal) developed hyperglycemia.

It is recognized that narcosis, however induced, is associated with changes in the blood sugar. Whether this change is due to specific drug effect, or whether it is a part of physiological changes associated with narcosis is an open question. Page's 1 observation that anesthesia induced by iso-amyl-ethyl barbituric acid (amytal) is not associated with blood sugar changes in rabbits and dogs is, therefore, of interest, though Bang 2 found that diethylbarbituric acid (veronal) raises the blood sugar of the rabbit, and Ellis and Barlow 3 state that the blood sugar of pigeons and cats is lowered several hours after the intraperitoneal injection of the sodium salt of diethylbarbituric acid (medinal).

In numerous investigations during the past years, various derivatives of barbituric acid, especially iso-amyl-ethyl barbituric acid (amytal) have been used for anesthesia, and from the blood sugar changes far reaching conclusions have been drawn as to changes in carbohydrate metabolism.

The investigation to be reported consists of fifty-three experiments on thirty-two cats and on five dogs. The freshly prepared sodium salts of diethybarbituric acid (in doses of 120, 150, 180, and 300 mg. per kilogram of body weight), of iso-amyl-ethyl barbituric acid (doses 38, 50, 60, 65, 80 mg. per kg. b. w.), and of iso-allyl-propyl barbituric acid (50, 60, 80 mg. per kg. b. w.) were injected intraperitoneally and intravenously. Blood sugar determinations were made according to Benedict's 4 “1925” method. After the blood sugar of the fasting animals was determined, repeated blood samples were taken up to six to twenty-four hours respectively following the administration of the hypnotics.