Use of a Microprocessor in the Control of Malignant Hypertension with Sodium Nitroprusside

Abstract

In a malignant hypertensive, steady control of blood pressure at a pre-determined level was achieved with the continuous i.v. infusion of sodium nitroprusside. A microprocessor was programmed to assess the patient''s blood pressure and adjust the rate of nitroprusside infusion so that a mean pressure of 106 mmHg was achieved. Brief interruption of the nitroprusside infusion allowed the effectiveness of changes in oral therapy to be evaluated. Thiocyanate concentrations were measured throughout as an index of potential nitroprusside toxicity. After 6 days blood pressure control was maintained with oral therapy alone and papilledema had almost resolved.