Comparison Of Bupivacaine And Bupivacaine With Nalbuphine For Subarachnoid Block In Patients Undergoing Lower Abdominal Surgeries, A One Year Randomised Controlled Trial

Abstract

Backgrounds: Spinal anaesthesia is a popular anaesthetic technique for lower abdominal surgeries and offers many advantages over general anaesthesia. Opioid analgesics which are common adjuvant to the local anaesthetics are associated with sedation, respiratory depression and postoperative nausea and vomiting. Nalbuphine however has a reduced incidence of respiratory depression and has been used to antagonize the side-effects of spinal opiates. In our study we investigated the effects of addition of nalbuphine (400mcg) to intrathecal hyperbaric bupivacaine. Objective: The objectives of the study were to compare onset, duration of sensory and motor blockade, duration of postoperative analgesia between hyperbaric bupivacaine and hyperbaric bupivacaine with nalbuphine (400mcg) in patients undergoing lower abdominal surgeries under spinal anaesthesia. Methods: This one year randomized controlled trial was conducted in the Department of Anaesthesiology, KLES Dr. Prabhakar Kore Hospital and Medical Research Centre, Belagavi during the period January 2016 to December 2016 After institutional ethical committee clearance and written informed consent 60 ASA physical status I and II patients undergoing lower abdominal surgeries under spinal anaesthesia were randomly allocated into two groups. Group A received 3ml of 0.5% hyperbaric bupivacaine with 400 mcg inj. Nalbuphine. Group B received 3ml of 0.5% hyperbaric bupivacaine with 0.5 ml of normal saline. Results: In our study, the mean onset of sensory blockade and motor blockade in nalbuphine group were 3.76+/- 0.86 min and 6.33+/-12 min and in control group were 3.53+/-0.75 min and 6.42+/-0.86 min respectively. The difference was statistically insignificant. The mean duration of sensory blockade and motor blockade in nalbuphine group were 118.93+/- 8.37 min and 144.28+/- 8.94 min and in control group 96.93+/- 7.10min and 121.21+/- 5.19 min respectively. The difference was statistically significant. The mean duration of postoperative analgesia was 222.93+/- 19.75 min in nalbuphine group as compared to 151.64+/-10.61 min in control group which was highly significant. Hemodynamic parameters were comparable between the two groups with no major side effects / complications observed. Conclusion: In conclusion, administration of 400 mcg nalbuphine intrathecally along with 0.5% hyperbaric bupivacaine has similar onset of sensory and motor blockade and significantly prolongs duration of blockade and postoperative analgesia without major adverse effects or hemodynamic changes.