PROPHYLACTIC ORAL EPHEDRINE REDUCES THE INCIDENCE OF HYPOTENSION AFTER SUBARACHNOID BLOCK

The purpose of this study was to demonstrate the efficacy of oral ephe drine in preventing hypotension following subarachnoid block. Two hund red women, ASA physical status I or II, undergoing lower abdominal sur gery were randomly divided into two groups (n = 100 each). All patient s were given routine oral premedication consisting of diazepam 10 mg a nd ranitidine 150 mg at bed time and at 90 min before surgery. In addi tion, Group I patients received ephedrine 30 mg, orally, 30 min before subarachnoid block was administered. Group II received only routine p remedication. After starting an iv line and preloading with 10 ml . kg (-1) crystalloid, patients were given 0.5% heavy bupivacaine 3.2 to 3. 6 ml, depending on body weight, intrathecally. Patients with decreases in blood pressure of 20% were given ephedrine iv, in increments, in a ddition to crystalloids. Despite a similar level of block (T-3-T-4) an d iv fluids, the total dose of ephedrine supplement in Group I was 4.3 +/- 4.8 mg compared with 11.6 +/- 9.4 mg in Group II (P < 0.01). Also , 55 patients in Group I required intraoperative inotrope supplement c ompared with 83 in Group II (P < 0.01). We conclude that oral ephedrin e premedication is a simple and effective way of reducing the incidenc e of hypotension in patients undergoing lower abdominal surgery under subarachnoid block.