ABSTRACT
The efficacy of intravenous captopril on plasma renin activity (PRA ) and angiotensinⅡ (All ) during isoflurane-induced hypotension were investigated. 24 patients (aged 20-50 years,ASA Ⅰ-Ⅱ )scheduled for elective cerebral surgery were randomly divided into two groups: Group I (isoflurane, n = 12 )and Group J (captopril 0. 15mg/kg plus isoflurane n=12 ). MAP was reduced approximately 30% in all of patients. Angiotensin Ⅱ concentration increased 260% during hypotension in group I, but only a slight reduction in Group Ⅱ. The end-expiratory concentration of isoflurane in Group I were higher than Group I during induced and hypotension period. It is concluded that intravenous captopril can inhibit the increase of PRA and All concentration and less isoflurane required for the deliberated hypotension. Induced-hypotension by the combination of isoflurane with captopril may be advantageous.