Effect of remifentanil on hemodynamic parameters of parturients and APGAR of the neonate in elective cesarean section under general anesthesia

Neonatal respiratory depression due to narcotics usage during cesarean section under general anesthesia is an important challenge for anesthesiologists. Remifentanil, due to its pharmacokinetic properties, may be a solution for this challenge. This study was designed to evaluate the effect of this drug on maternal hemodynamics and Apgar scores of their neonates during cesarean section under general anesthesia. In this double blind randomized controlled clinical trial, 84 women who were candidates for elective cesarean section under general anesthesia were randomly allocated into three groups. In the first group remifentanil was infused at a rate of 0.5μg/kg/min and the second group received an IV bolus of 0.7 μg/kg of the drug. Control group received an equivalent volume of normal saline. Maternal heart rate and blood pressure were measured and recorded before induction of anesthesia and one minute after tracheal intubation. Neonatal Apgar scores in the first and fifth minutes postnatal were also recorded and compared. Mean maternal HR changes before and after tracheal intubation were not significant between groups (P= 0.33). Mean arterial pressure (MAP) changes between groups were significantly different (P= 0.001). MAP changes were smallest in the bolus group and largest in the control group. These changes were not significantly different between infusion and control groups (P= 0.994). This difference was significant between the bolus group with the infusion and control groups (P=0.001 and 0.002 respectively). The mean first minute Apgar scores in neonates were significantly different in three groups (p=0.006). This parameter was not significantly different between bolus and infusion groups (p=0.603). Mean first minute Apgar scores in the bolus (8.46) and infusion (8.31) groups were significantly less than the control (8.93) group (p= 0.005 and 0.002 respectively). The mean fifth minute Apgar scores were not significantly different between three groups. None of the neonates in the remifentanil groups needed resuscitation. The results indicated that bolus administration of remifentanil (compared with infusion and control groups) produces more stability in maternal blood pressure during cesarean section under general anesthesia. The decrease in first minute Apgar score in remifentanil groups were clinically negligible (none of these neonates needed resuscitation). Despite these results, multicenter studies more samples are needed to confirm using remifentanil in elective cesarean section.