Continuous Alprenolol Infusion for Control of Hypertension in the Acute Stage of Ruptured Intracranial Aneurysms

The clinical benefits and hemodynamic effects of continuous alprenolol infusion for control of hypertension in the acute stage of ruptured cerebral aneurysms were investigated. Twenty-five patients manifesting systemic hypertension (> 160/100 mmHg) were treated with alprenolol, a β-adrenergic antagonist, phentolamine, an α-adrenergic antagonist, and trimethaphan camsilate, a ganglionic blocker, given intravenously. All drugs decreased the mean arterial blood pressure significantly. However, alprenolol decreased the heart rate and cardiac index while phentolamine increased them. Alprenolol also decreased arterial catecholamine and renin activity, but caused no change in central venous pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, and systemic vascular resistance. The results indicate the usefulness of continuous alprenolol infusion for the control of acute hypertension in hemorrhagic cerebrovascular disease. The mode of action of alprenolol is also discussed.