Safety and efficacy of intrathecal adjuvants for cesarean section: bupivacaine, sufentanil, or dexmedetomidine

Context Coadministration of adjuvants with bupivacaine for spinal anesthesia is advocated to reduce its dose and improve the quality of intraoperative and postoperative analgesia with the least number of side effects. Aim The aim of the study was to compare the efficacy and safety of three intrathecal regimens for cesarean section. Patients and methods Ninety patients of ASA grade I or II who were scheduled for cesarean section under spinal anesthesia were randomly allocated into three groups of 30 patients each. Group B was injected with 15 mg of 0.5% hyperbaric bupivacaine, group F was injected with 10 mg of 0.5% hyperbaric bupivacaine +10 μg of sufentanil, and group D was injected with 10 mg of hyperbaric bupivacaine +10 μg of dexmedetomidine. Study parameters were as follows: mean arterial blood pressure, heart rate, respiratory rate, oxygen saturation (SpO2), sedation scores, side effects (such as hypotension, bradycardia, nausea/vomiting, shivering, pruritus, respiratory depression), neonatal outcome, onset and duration of sensory and motor block, intraoperative and postoperative analgesic requirements, and duration of complete and effective analgesia. Results There were no significant differences regarding mean arterial blood pressure, heart rate, respiratory rate, SpO2, and neonatal outcome among the study groups. Sedation scores were higher in group D compared with groups B and S. Onset of motor block was comparable among the three groups, whereas onset of sensory block, time to two-segment regression and regression time to sensory S1, and motor recovery time were longer in groups D and S compared with group B. Intraoperative analgesic requirements showed no significance among the three groups, whereas duration of complete and effective analgesia was longer in groups S and D compared with group B. Further, postoperative 24 h analgesic requirements were higher in group B compared with groups S and D. Side effects such as hypotension, bradycardia, shivering, and respiratory depression were comparable among the study groups, whereas nausea/vomiting and pruritus were higher in group S compared with groups B and D. Conclusion Addition of sufentanil or dexmedetomidine to hyperbaric bupivacaine for intrathecal block prolongs the duration of sensory and motor block and reduces postoperative analgesic requirements. Sufentanil has a higher incidence of nausea/vomiting and pruritus, whereas dexmedetomidine has better analgesic effects and sedation without respiratory depression.