Retrospective evaluation of intravenous fentanyl patient-controlled analgesia during labor

Because the safety of intravenous fentanyl patient-controlled analgesia (iv-PCA) administered during labor remains unclear, we retrospectively examined the labor records from January 2005 to December 2007 in our institution, with a focus on both maternal and neonatal outcomes, as compared to no analgesia.

Parturients over 35 weeks of gestational age who received fentanyl iv-PCA (iv-PCA group) or no analgesia (control group) during labor were enrolled. The former group received iv-PCA through a pump programmed to give a loading dose of 0.05 mg fentanyl, followed by bolus injection of 0.02 mg fentanyl, with a lock-out interval of 5 min. This analgesia was initiated at the parturient's request and was discontinued before the second stage of labor, to ensure neonatal safety. During labor, both maternal and fetal heart rates, maternal pulse oximeter oxygen saturation (SpO(2)), respiratory rate, and sedation and nausea scores were continuously monitored, and the neonatal outcomes including umbilical arterial pH, Apgar scores, and other parameters were recorded.

The data of 129 of the 143 parturients who received fentanyl iv-PCA were analyzed, while 697 parturients delivered without any analgesia during the 3-year study period. While iv-PCA prolonged the duration of labor and increased oxytocin use, no obvious maternal or neonatal complications of fentanyl use were recorded. Except for the significantly lower rate of emergency cesarean section in the iv-PCA group, both the maternal and neonatal outcomes were comparable between the groups.

As compared to no analgesia, fentanyl iv-PCA appears to be safe and clinically acceptable as analgesia during labor, particularly in nulliparous women.