Role of Epidural Nalbuphine as Adjuvant In Perioperative Pain Management in Lower Limb Surgeries

Introduction: The Opioids are frequently used as adjuncts to local anesthetics in epidural anesthesia. Although the systemic use of narcotic analgesics does provide acceptable analgesia, but when these drugs are used through epidural route, they provide superior quality of analgesia without systemic side effects. Nalbuphine is one such opioid which has been used extensively via systematic route but not through epidural pathway. Aims: We aim to study the efficacy and duration of postoperative analgesia and safety of Bupivacaine with nalbuphine via epidural route for lower limb surgeries. Settings and Design: A prospective, randomized and double-blind study was conducted involving 80 patients for elective lower limb surgeries carried under epidural anesthesia. Methods and Material: Epidural anesthesia at L1-2 space was given with 15 ml bupivacaine(0.5%) in control group and 15ml of bupivacaine(0.5%) with nalbuphine (10mg in 1ml) in the test group. The time to reach the sensory and motor blockade as well as duration of same along with quality and duration of analgesia was assessed along with any side effects such as respiratory depression, sedation or vomiting etc. Results: The Mean time of onset of sensory blockade with Nalbuphine as adjuvant observed in present study is found to be 5.4 ±1.12 minutes while that without adjuvant was 15.95± 2.64 minutes(p<0.005). The mean duration of analgesia in group receiving nalbuphine was 287.37± 23.72 minutes which was significantly longer (P value = 0.001) when compared to control group which had mean duration of sensory blockade of 162.95 ± 37.89 minutes. Similarly, the mean time to achieve complete motor blockade was significantly (p value<0.0001) earlier (12.35 ± 1.24 minutes) in Nalbuphine group compared to control group (23.04 ±2.80 minutes) and the duration of motor block was significantly longer as well in the group receiving epidural nalbuphine (168.85 ± 16.76 in nalbuphine group vs 120.25 ± 20.51minutes in control group with p value <0.0001). The hemodynamic parameters were comparable in both the groups and no significant respiratory depression or any other side effect was noted. Conclusions: The addition of nalbuphine with bupivacaine epidurally was effective for postoperative analgesia in terms of quality and duration of analgesia without any systemic side effects or hemodynamic instability