Intravenous dexmedetomidine enhances the experience of visceral pain in parturients during cesarean delivery under spinal anesthesia

Background and hypothesis Visceral pain is a common incidence in cesarean delivery under spinal anesthesia. Dexmedetomidine (DEX) has analgesic, sedative, anxiolytic effect, as it is an α 2-receptor agonist. Intraoperative visceral pain resulting from manipulation of the uterus and traction of the peritoneum is still a challenge for anesthetists. The present study hypothesized that single intravenous bolus dose of DEX added as a supplement to intrathecal anesthesia for an elective cesarean section could reduce intraoperative visceral pain, lessen blood pressure swings, and produce an acceptable sedative effect, with minimal fetal and maternal consequences. Patients and methods A randomized double-blinded placebo-controlled study was conducted. A total of 70 patients were randomly allocated to receive either intravenous DEX or placebo (saline) before spinal anesthesia. The primary outcomes were decreased intraoperative visceral pain. Secondary outcomes included the stability of hemodynamic parameters (blood pressure and heart rate), sedation score, time to rescue analgesia reduction, neonatal APGAR score, and any adverse effects (nausea and vomiting). Results There was a significant difference between the groups in the incidence of moderate to severe visceral pain (P<0.001), intraoperative fentanyl requirements (P=0.004), and longer time to rescue analgesia (P<0.001). Both groups had comparable mean blood pressure (P>0.005); however, there was a highly significant difference in heart rate (P=0.01). Moreover, a significantly higher sedation score was seen in the DEX group (2.08±0.8) in comparison with the control group (1±0). APGAR score was comparable in the studied groups. Conclusion As a single intravenous bolus, DEX seems to be an excellent supplement to intrathecal anesthesia for an elective cesarean section. It can reduce intraoperative visceral pain and lessen blood pressure swings and produce an acceptable sedative effect with minimal fetal and maternal influence.