UNILATERAL SPINAL ANESTHESIA FOR LOWER EXTREMITY SURGERY

Abstract

Objective: To compare the efficacy of unilateral spinal anesthesia by heavy bupivacaine with conventional bilateral anesthesia for lower extremity surgery. Methods: In this prospective randomized study, eighty two patients undergoing elective lower extremity orthopedic surgery were randomly allocated into two groups, unilateral and bilateral. All patients received intrathecally 8 mg of hyperbaric bupivacaine 0.5% over 40 seconds at the L3-4 intervertebral space. A lateral decubitus position after spinal injection was maintained in the unilateral group for 15 min. The onset and recovery of sensory and motor block and perioperative side effects were recorded. Results: Success rate of unilateral anesthesia was 82.9%. In the unilateral group, the sensory block for surgery (above L1) (181.5 ± 18.9 versus 150.0 ± 20.1 min), motor block time (149.3 ± 18.4 versus 121.5 ± 16.4 min) were longer and incidence of hypotension (2.4 versus 29.3%) was lower than those in the bilateral group. Onset of sensory block (3.5 ± 1.1 versus 3.3 ± 0.9 min), succes rate of anesthesia (100% in both groups), incidences of intraoperative nausea, vomiting and agitation and postoperative nausea, vomiting, headache and heart rate, respiratory changes were not significant between two groups. Conclusion: Unilateral spinal anesthesia provided longer sensory and motor block, lower incidence of hypotention in comparison with conventional bilateral anesthesia. This is a suitable technique for lower limb orthopedic procedures. Key words: Unilateral spinal anesthesia, lower extremity surgery