Comparison of hemodynamic and postoperative analgesic effects and recovery of unilateral and bilateral spinal anesthesia

OBJECTIVE: To compare unilateral with bilateral spinal anesthesia according to hemodynamic, postoperative analgesic effects and recovery.

METHODS: This study took place in Ankara Numune Hospital, Ankara, Turkey, between March and July 2004. We accepted 60 patients undergoing elective lower extremity orthopedic surgery for the study, and randomly allocated the patients into 2 groups, bilateral and unilateral. We performed crystalloid preload spinal puncture at the L4-5 intervertebral space with a 25-gauge Quincke needle. Both groups received local anesthetic while lying in the lateral position, dependent on the side to be operated. All the patients had 10 mg 0.5% hyperbaric bupivacaine injected over 40 seconds. Only the patients in the unilateral group remained in the lateral position for 15 minutes. We measured noninvasive mean arterial blood pressure and heart rate before spinal blockade and then after 5, 15, 30, and 45 minutes. We also recorded motor block regression time and first analgesic need. We analyzed the data using Mann-Whitney U, Wilcoxon, and Chi-square tests, considering p<0.05 as significant.

RESULTS: We observed no significant differences regarding height, age, and weight. In both groups, heart rate and mean arterial pressure showed a decrease after spinal blockade. Recovery time and the first analgesic need in the unilateral group were higher than the bilateral group.

CONCLUSION: Because of its long lasting analgesic effect without any hemodynamic change, we suggest unilateral spinal block for lower extremity orthopedic procedures.