Comparison of ephedrine and etilefrine for the treatment of arterial hypotension during spinal anaesthesia in elderly patients.

Thirty ASA II-III patients (greater than 65 years) undergoing hip surgery under bupivacaine spinal anaesthesia, and presenting a 25% reduction in mean arterial pressure (MAP), were included in the study. The patients were randomly allocated to receive, under double-blind conditions, either ephedrine 0.07 mg kg-1 or etilefrine 0.03 mg kg-1 boluses i.v. when MAP decreased by 25% from the preanaesthetic reference value. There were no significant differences (mean +/- s.d.) in the time interval between the sympathomimetics administered (ephedrine 20.2 +/- 17.1 min, etilefrine 16.6 +/- 7.0 min) or the number of sympathomimetics needed (ephedrine 3.8 +/- 1.9, etilefrine 3.6 +/- 2.2). In regard to MAP and diastolic arterial pressure (DAP), ephedrine was slightly more potent in restoring arterial blood pressure compared with etilefrine. The increases in systolic arterial pressure (SAP) and heart rate were similar in both groups. The administration of repeated doses of either sympathomimetic showed the same tendency to increase SAP, DAP, and MAP values as the first dose.