Abstract
Induced hypertension was done for 9 patients with vasospasm after ruptured aneurysm. Dopamine for 6 patients and Angiotension II for 3 patients were used for hypertension when the clinical sign of the vasospasm appeared. Cerebral blood flow (by Argon inhalation method) and cardiac function (by Swan-Ganz catheter and thermodilution method) were examined before and after the drug infusion. In one case Xe-CT CBF study was performed and this study showed marked increase of CBF at the part of vasospasm in relation to the increase of blood pressure.
At the hypertensive state, the increase of total cerebral blood flow and improvement of clinical signs were found. As the cause of increased cerebral blood flow at the hypertensive state, local disruption of autoregulation shown in Xe-CT CBF study was suggested, although direct actions of these drugs to cerebral vessels could not be denied.
At the point of cardiac function Dopamine increased cardiac output in relation to its dose. An increase of the blood pressure was not found at the dose of 8μg/kg/min but found at 20μg/kg/min. Angiotensin II decreased cardiac output and increased total vascular resistance and blood pressure in relation to its dose. Angiotensin II should be used carefully especially for patients with heart disease because of its vasoconstrictive action.
