Oral Glycerol for the Reduction of Intracranial Pressure

Abstract

ITERATURE of recent years reports several works on the clinical use of hypertonic solutions administered by slow intravenous infusion for reduction of intracranial pressure. 3,7-9,~3,19 Among the numerous osmotic agents tested to reduce experimentally induced cerebral edema in the animal, 15 glycerol has proved particularly effective both by intravenous and oral route. TM Considering such experimental results, glycerol has been applied on neurologicalfl ophthalmological 16,17 and, chiefly, neurosurgical 2 patients. Glycerol (1,~,3-propanetriol) is a trivalent alcohol. I t is oxidized by the organism through intermediate stages, analogous to those of the carbohydrate-oxidation cycle. As an integral part of fats (glycerides) and phosphatides, glycerol usually is present in the animal tissues at a rate of approximately 1 per cent of body weight. Oxidized to carbon dioxide and water, it produces 4.3~ kg. calories per gm. 6 Such value is slightly greater than that produced by glucose. When larger amounts of glycerol are given, however, the drug is not metabolized completely by the organism since part of it is excreted in the urine.n ,12 Glycerol increases plasmatic concentration. 14 Its mechanism of action, therefore, would be to draw liquids from the tissues, particularly from those more hydrated. At convenient doses, glycerol promotes diuresis; L4,2~ yet diuresis itself does not condition the action of the drug since reduction of intracranial hypertension in the nephrectomized animal did not differ from that obtained in the normal animalY In 19~9, Ferber and Rabinowitsch 5 de-