Background: The purpose of this study is to evaluate the clinical effectiveness, block quality and hemodynamic effects of low dose hyperbaric levobupivacaine and also compare it with low dose hyperbaric bupivacaine when they are combined with fentanyl in spinal anesthesia for MTP with sterilisation surgery.

Material and Methods: This was hospital based, comparative, randomized controlled ,double blind interventional study. The study was conducted in 90 patients of ASA grade I and grade II between 20-50 years, weighing between 40-70 kg, scheduled to undergo elective MTP with sterilization. They were randomly assigned to two groups. Group A received 7.5 mg(1.5 ml) of 0.5% isobaric levobupivacaine + 1 ml of 5% dextrose and fentanyl 25 mcg(0.5 ml) and Group B received 7.5 mg(1.5 ml) of 0.5% hyperbaric bupivacaine +1ml of normal saline and fentanyl 25mcg. The onset and duration of motor and sensory block, haemodynamics, postoperative analgesia and incidence of side effects were compared.

Results: Mean arterial pressures and heart rates were comparable and stable in both groups.The time to T10 dermatome level, time to maximum sensory block and time to onset of motor block were significantly higher in group A.The duration of motor block was significantly shorter in group A as compared to group B. In Group B,the percentage of patients with complete motor blockade was significantly higher than group A. Two segment regression times did not differ significantly in both groups. The time to full recovery of sensory block was significantly longer in group A than group B. First analgesic requirement time of group A was significantly longer than group B.

Conclusion: The use of low dose hyperbaric levobupivacaine may be preferable to low dose hyperbaric bupivacaine due to relative reduction in motor blockade, shorter motor blockade time, longer sensory blockade time and longer time to first analgesic requirement.