Nalbuphine versus midazolam as an adjuvant to intrathecal bupivacaine for postoperative analgesia in patients undergoing cesarean section

Abstract

Background and Purpose: Adding adjuvants to intrathecal hyperbaric bupivacaine pro-vides long analgesic duration with less adverse effects. The aim of this study was to compare intrathecal nalbuphine versus midazolam in patients undergoing cesarean section. Clinical Trial ID: NCT03918187. Patients and Methods: This was a prospective randomized controlled study conducted on 90 females undergoing cesarean section under spinal anesthesia who were randomly allo-cated to three equal groups of 30 patients each: group C received hyperbaric bupivacaine 12.5 mg plus 0.5 mL saline, group N received hyperbaric bupivacaine 12.5 mg plus 1 mg nalbuphine, group M received hyperbaric bupivacaine 12.5 mg plus 2.5 mg midazolam. The onset and duration of sensory and motor block, effective analgesic time, analgesic require-ments, adverse effects, sedation, and Apgar scores were recorded. Results: There was significant rapid onset of sensory and motor block (1.95±.44 and 3.50 ±0.43 min) with slower regression of sensory block and time to bromage I (211.6±13.2 and 219.8±20.2 min) in group N compared to groups M, C (p < 0.001), with statistically significant rapid onset and long duration of both blocks in group M compared to C (p<0.001). The effective analgesic time was significantly prolonged in group N (263.7 ±16.3) compared to groups M and C (224.2 ± 18.6, 185.5±17.45), respectively, (p<0.001) and prolonged in group M compared to C (p<0.001), with increase in analgesic requirement in group C compared to groups N and M (p<0.001) and no significant difference between groups N and M. There was higher sedation score in groups N, M (1.78±0.63, 2.75±0.54), respectively, compared to group C (0.61±0.12) (p<0.001) with lower Apgar score in group M (6.9±0.73) at one minute than in groups N, C (7.1±0.91, 7.7±0.84) (p<0.001). There was no significant difference between groups regarding the adverse effects. Conclusion: Adding 1 mg nalbuphine to 12.5 mg hyperbaric bupivacaine provided more effective postoperative analgesia than adding 2.5 mg midazolam, with less non-significant adverse effects in midazolam group in patients undergoing elective cesarean section.