The effect of intrathecal compared with intravenous dexmedetomidine as an adjuvant to spinal bupivacaine anesthesia for cesarean section

Abstract

Introduction The aim of this study was to evaluate the effect of intrathecal compared with intravenous dexmedetomidine as an adjuvant to spinal bupivacaine anesthesia for pregnant women undergoing cesarean section on intraoperative and postoperative analgesia with special emphasis on their sedative properties and on the neonatal outcome. Patients and methods A total of 105 women of ASA physical status I or II at term pregnancy were enrolled randomly into three groups. Patients in group I received spinal anesthesia with hyperbaric bupivacaine. In group II, 5 μg dexmedetomidine was added to bupivacaine. In group III, after administration of spinal anesthesia with bupivacaine and an intravenous infusion of 0.5 μg/kg/h dexmedetomidine throughout the surgery, the incidence of hypotension, bradycardia, the onset, and the duration of sensory and motor block and the postoperative pain score were assessed. Results No differences were observed in the rate of occurrence of hypotension and bradycardia between the three groups. The time to reach the peak sensory level was shorter in group II and group III with a longer duration compared with group I. The duration of motor block was shorter in group I compared with the two other groups with no significant difference between the three groups in the onset of motor block. The onset of postoperative pain was significantly earlier in group I, and more patients in group I needed supplementary analgesia. No significant difference was noted between the three groups regarding the Apgar score and the incidence of maternal side effects such as nausea, vomiting, and dryness of the mouth. Conclusion The use of intrathecal dexmedetomidine or intravenous dexmedetomidine as an adjuvant to spinal bupivacaine in women undergoing elective cesarean section improved the intraoperative condition and the quality of postoperative analgesia without neonatal or maternal side effects.