Combination of dexmedetomidine and remifentanil for labor analgesia: A double-blinded, randomized, controlled study

Background: Satisfactory analgesia is of great importance in the labor. The clinical efficacy and side effects of remifentanil in the management of labor pain had been evaluated. Dexmedetomidine (DMET) demonstrates an antinociceptive effect in visceral pain conditions. Aims of the study were to assess whether the combination of DMET with remifentanil would produce a synergistic effect that results in lower analgesic requirements. Furthermore, whether this combination would have less maternal and neonatal adverse effects. Patients and Methods: Sixty American Society of Anesthesiologists physical status I-II pregnant women had been enrolled into this study. All were full term (37-40 weeks gestation), singleton fetus with cephalic presentation in the first stage of spontaneous labor. They were divided into two groups group (I) Patient-controlled IV remifentanil analgesia (bolus dose 0.25 mu g/kg, lockout interval 2 min) increased by 0.25 mu g/kg to a maximum bolus dose 1 mu g/kg in addition to a loading dose of DMET 1 mu g/kg over 20 min, followed by infusion at 0.5 mu g/kg/h group (II) Patient-controlled IV remifentanil analgesia (PCA) (bolus dose 0.25 mg/kg, lockout interval 2 min) increased by 0.25 mu g/kg to a maximum bolus dose 1 mu g/kg in addition to a the same volume of normal saline as a loading dose, followed by a continuous saline infusion. Visual analog scale score, maternal, and fetal complications and patients satisfaction were recorded. Results: Patients receiving a combination of PCA remifentanil and DMET had a lower pain score compared with remifentanil alone in the second stage of labor (P = 0.001). The Total consumption of remifentanil was reduced by 53.3% in group I. There was an increased incidence of maternal complications and a lower patient satisfaction score in group II. Conclusion: DMET has an opioid sparing effect; a combination of DMET and remifentanil produces a synergistic effect that results in lower analgesic requirements and less maternal and neonatal adverse events.