Comparison of analgesic efficacy of fentanyl and dexmedetomidine as adjuvant to intrathecal hyperbaric 0.75% ropivacaine for lower abdominal surgeries—A prospective double-blind randomised controlled study

Aims and Objectives Various adjuvants are used to prolong intraoperative and postoperative analgesia after spinal anaesthesia. This study aimed to compare the onset and duration of sensory and motor block, haemodynamic effects, postoperative analgesia, and adverse effects of intrathecal dexmedetomidine or fentanyl as adjuvants with hyperbaric 0.75% ropivacaine. Material and Methods 100 American Society of Anesthesiologists I and II patients, between ages 20 and 60 years, undergoing elective lower abdominal surgeries were randomised to receive 3 ml of 0.75% hyperbaric ropivacaine with either 10 µg dexmedetomidine or 25 µg fentanyl as adjuvants intrathecally. Patients were assessed for the onset and duration of sensory and motor block, haemodynamic effects, two-segment sensory regression, duration of postoperative analgesia, postoperative pain scores, and any adverse effects. Results There was a significant difference (p = 0.033) between the two groups regarding the time for two-segment regression, with group D patients taking longer (144.88 ± 28.39 minutes) compared to group F (131.86 ± 31.61 minutes). The duration of analgesia was also significantly longer, p < 0.001, in group D (431.82 ± 85.38 minutes) than in group F (308.38 ± 66.92 minutes). Similarly, the duration of motor blockade was significantly longer in group D (360.86 ± 68 minutes) compared to group F (274.92 ± 70 minutes) (p < 0.001). A statistically significant difference in postoperative analgesic consumption between the two groups (p = 0.002), with patients in group F requiring more analgesics was observed. Conclusion 10 µg of dexmedetomidine provides a longer duration of anaesthesia and analgesia compared to 25 µg of fentanyl as an intrathecal adjuvant to hyperbaric 0.75% ropivacaine for abdominal surgeries.