Comparison of Postoperative Analgesia Between Intrathecal Nalbuphine and Intrathecal Fentanyl in Infraumbilical Surgeries: A Double-Blind Randomized Controlled Trial.

Abstract

Spinal anesthesia is a widely used regional anesthesia technique for surgeries below the umbilicus, butpostoperative analgesia is of major concern due to the relatively short duration of the local anesthetic. Various drugs were used as an additive to local anesthetic to prolong the duration of postoperative analgesia. This study aims to compare the efficacy ofnalbuphine and fentanyl as an intrathecal additive along with local anesthetic. A total of 166 patients aged between 18 and 65 years belonging to the American Society of Anesthesiologists(ASA) I and II undergoing elective infraumbilical surgeries were included in the prospective double-blind randomized controlled trial. The patients were allocated into two groups of 83 each. Group N was given 2.5 mL of 0.5% bupivacaine + 1 mg of nalbuphine (0.5 mL), and group F received 2.5 mL of 0.5% bupivacaine + 25 mcg fentanyl (0.5 mL). Both groups were compared for postoperative analgesia, onset and duration ofboth sensory and motor blockade, intraoperative hemodynamics, and side effects. All demographic data, hemodynamic parameters, and side effects were not statistically significant among the two groups. However, other parameters, such as the mean duration of analgesia, which was 267.27 ±172.099 minutes in group N and 161.35 ±14.957 minutes in group F; meantime for the onset of sensory blockade, whichwas 3.94 ±1.769 minutes in group N and 5.94 ±0.929 minutesin group F; onset of complete motor blockade, which was 7.10 ±1.858 minutes in group N and 11.61 ±1.218 minutes in group F; duration of motor blockade, which was 182.57 ±13.011 minutes in group N and 112.53 ±7.389 minutes in group F;and mean time taken for two-segment regression, which was 118.20 ±12.61 minutes in group N and 113.72 ±8.84 minutes in group F, were all comparable between the two groups. Nalbuphine was found to be more efficacious for prolongation of postoperative analgesia with better hemodynamic stability.