The Effect of Hexamethonium upon Cerebral Blood Flow and Metabolism in Patients with Premalignant and Malignant Hypertension

Abstract

In 13 patients with grade III or grade IV hypertensive retinopathy the effect of intramuscular hexamethonium bromide on cerebral circulation and metabolism has been studied. The results have been compared with Dewar's study of hexamethonium in less severe hypertensive patients and with Kety's results following differential spinal sympathetic block. Sixty minutes after intramuscular hexamethonium, mean arterial blood pressure fell 39 per cent, cerebral vascular resistance was reduced 29 per cent, and cerebral blood flow decreased 16 per cent. Cerebral oxygen consumption was maintained at the expense of a reduction in cerebral venous oxygen saturation.