Comparison of intrathecal dexmedetomidine and intrathecal fentanyl as an adjuvant with hyperbaric bupivacaine for spinal anaesthesia in lower limb surgeries: A prospective randomized clinical trial

Abstract

Subarachnoid block is the most common technique employed for lower limb surgeries. When used as an adjuvant to intrathecal local anaesthetic, both fentanyl and dexmedetomidine have the ability increase perioperative analgesia. This study aimed to compare and evaluate the effective profile of dexmedetomidine and fentanyl as an adjuvant to intrathecal bupivacaine in lower limb surgeries.In this clinical trial, 90 patients undergoing elective lower limb surgeries under spinal anaesthesia were randomly allocated to two groups. In group BD, the patients received 0.5% hyperbaric bupivacaine 12.5 mg + dexmedetomidine 5 mcg. In group BF, the patients received 0.5% hyperbaric bupivacaine 12.5 mg + fentanyl 25 mcg. Onset, duration, regression of sensory and motor blockade along with haemodynamic variations and side effects were compared between both the groups.The onset of sensory block was earlier in Group BD, while the onset of motor block was earlier in Group BF. However, the differences with the onset of sensory and motor block remained statistically insignificant (P = 0.4988 and 0.4918). The mean time for two-segment sensory regression, time for regression to L1 dermatome and duration of motor block was significantly less in Group BF. The analgesic requirement in the early postoperative period and the haemodynamic variation remained statistically insignificant in both the groups. Intrathecal dexmedetomidine provided prolonged sensory as well as motor blockade thereby enhancing postoperative analgesia.