[The effect of low dose dopamine on CBF in patients with subarachnoid hemorrhage]

Cerebral blood flow was measured in 10 patients with subarachnoid hemorrhage using the 133Xe inhalation methods. Regional cerebral blood flow (r-CBF) values were calculated with initial slope index, their values were compared with the blood flow response to the administration of low dose dopamine (DA). CBF values of just after and continuous administration of DA were compared with control values. The measurement of r-CBF was performed immediately after the infusion of 5 micrograms/kg/min DA for 30 min. The focal ischemic lesions decreased, bi-hemispheric mean CBF value (7 cases without A-Com patients) increased by 10.3% significantly (paired T test), affected hemispheric mean CBF value increased by 8.7% significantly and non-affected hemispheric mean CBF value increased by 16.6% significantly. The PaCO2 value didn't change but the mean systemic blood pressure increased by 5.1% significantly. The CBF values of continuous administration of DA for 10 days to 2 weeks were measured. The CBF values increased during the administration of DA. The mean CBF values increased without the steal phenomenon and the mean arterial blood pressure increased slightly after the administration of DA. These phenomena were observed more significantly in non affected side than affected side. We suggest that the administration of DA increase the CBF values in patients with subarachnoid hemorrhage due to the stimulation of DA receptor.