Maternal and neonatal effects of nalbuphine given immediately before induction of general anesthesia for elective cesarean section.

BACKGROUND

Although nalbuphine was studied extensively in labour analgesia and was proved to be acceptable analgesics during delivery, its use as premedication before induction of general anesthesia for cesarean section is not studied. The aim of this study was to evaluate the effect of nalbuphine given before induction of general anesthesia for cesarean section on quality of general anesthesia, maternal stress response, and neonatal outcome.

METHODS

Sixty full term pregnant women scheduled for elective cesarean section, randomly classified into two equal groups, group N received nalbuphine 0.2 mg/kg diluted in 10 ml of normal saline (n=30), and group C placebo (n=30) received 10 ml of normal saline 1 min before the induction of general anesthesia. Maternal heart rate and blood pressure were measured before, after induction, during surgery, and after recovery. Neonates were assisted by using APGAR0 scores, time to sustained respiration, and umbilical cord blood gas analysis.

RESULT

Maternal heart rate showed significant increase in control group than nalbuphine group after intubation (88.2±4.47 versus 80.1±4.23, P<0.0001) and during surgery till delivery of baby (90.8±2.39 versus 82.6±2.60, P<0.0001) and no significant changes between both groups after delivery. MABP increased in control group than nalbuphine group after intubation (100.55±6.29 versus 88.75±6.09, P<0.0001) and during surgery till delivery of baby (98.50±2.01 versus 90.50±2.01, P<0.0001) and no significant changes between both groups after delivery. APGAR score was significantly low at one minute in nalbuphine group than control group (6.75±2.3, 8.5±0.74, respectively, P=0.0002) (27% of nalbuphine group APGAR score ranged between 4-6, while 7% in control group APGAR score ranged between 4-6 at one minute). All neonates at five minutes showed APGAR score ranged between 9-10. Time to sustained respiration was significantly longer in nalbuphine group than control group (81.8±51.4 versus 34.9±26.2 seconds, P<0.0001). The umbilical cord blood gas was comparable in both groups. None of the neonates need opioid antagonist (naloxone) or endotracheal intubation.

CONCLUSION

Administration of nalbuphine before cesarean section under general anesthesia reduces maternal stress response related to intubation and surgery, but decreases the APGAR score at one minute after delivery. So, when nalbuphine was used, all measures for neonatal monitoring and resuscitation must be available including attendance of a pediatrician.