ABSTRACTObjectives: Intrathecal fentanyl and clonidine are effective analgesics with different mechanisms of action. This study compares 25 µg of both thesedrugs given intrathecally regarding onset, quality, and duration of hyperbaric bupivacaine-induced spinal block and side effects.Methods: A total of 90 patients of ASA I and II were randomly allocated into three equal groups. Group A received 0.5 ml of 0.9% normal saline(placebo), Group B and Group C received 25 µg fentanyl and clonidine intrathecally added to 2.5 ml of 0.5% hyperbaric bupivacaine, respectively. Theonset and regression time of sensory and motor blocks were recorded along with hemodynamic change, side effects, pain intensity (in terms of visualanalog score (VAS), and time to first rescue analgesic.Results: Intrathecal clonidine (25 μg) significantly prolongs sensory and motor blocks, with prolonged duration of analgesia in comparison withintrathecal fentanyl (25 µg) (325±15 minutes vs. 240±7.6 minutes). VAS score was similar, but sedation was more in clonidine group.Conclusion: We conclude that low-dose intrathecal clonidine is an effective adjuvant to bupivacaine for spinal anesthesia and provides betterpostoperative analgesia in comparison with intrathecal fentanyl.Keywords: Clonidine, Fentanyl, Bupivacaine, Regional, Spinal, Postoperative pain.
Low-dose (5 mg) hyperbaric bupivacaine for unilateral spinal anesthesia in arthroscopic knee surgeries
