HYPERTENSIVE CRISIS MANAGED BY COMPUTER-CONTROLLED INFUSION OF SODIUM-NITROPRUSSIDE - MODEL FOR THE CLOSED-LOOP ADMINISTRATION OF SHORT-ACTING VASOACTIVE AGENTS

Nitroprusside infusion has been controlled by computer in 12 cases of hypertensive crisis. Pretreatment mean arterial pressure varied from 134 to 165 mm Hg. Nitroprusside infusion was commenced manually, a set point for mean arterial pressure specified and computer control commenced. Each 2 min the computer compares mean arterial pressure with the set point. For mean arterial pressures 10 mm Hg or more above the set point, the infusion rate increases by 5%. For mean arterial pressures 10 mm Hg or more below the set point, the infusion is decreased in rate or stopped depending on the level of pressure. The percentage of time mean arterial pressure was maintained within ±10 mm Hg of the set point averaged 75%, within a ±15 mm Hg range 88%, and within a ±20 mm Hg range 94%. The system has been successful in the management of patients with complicated hypertension. © 1979.