Epidural oxycodone accelerates onset, prolongs duration of analgesia during labour

Using oxycodone in addition to ropivacaine confers benefits for the timing of onset and duration of epidural analgesia during labour without contributing to an increase in adverse neonatal outcomes, according to the results of a trial. However, it may lead to a greater incidence of maternal pruritus.

Eighty nulliparous parturients requiring epidural analgesia were randomly assigned to the following treatment groups: active, which received 0.2 mg/mL oxycodone plus 0.1% ropivacaine, and control, which received 0.1% ropivacaine alone.

The effect of treatment was assessed in relation to the following outcomes: onset time and duration of analgesia, duration of labour stages, delivery outcome, analgesic effect, Bromage scores, blood pressure, heart rate and neonatal Apgar scores. Researchers also analysed umbilical arterial blood and recorded any side effects.

Compared with the control group, the active group had lower visual analogue scale (VAS) of pain at 2 and 4 hours after analgesia (p=0.021 and p=0.018, respectively), as well as 10 cm cervical dilatation (p=0.009).

The onset of analgesia occurred earlier among patients in the active group (mean, 13.3 vs 14.9 minutes; p=0.032). There were no marked between-group differences observed in the duration of labour stages, delivery outcome, Bromage score, neonatal Apgar score and umbilical arterial blood pH.

Moreover, the duration of analgesia was significantly longer in the active vs control group (mean, 326.2 vs 68.4 minutes; p=0.000), although the incidence of pruritus was numerically higher in the former (10 percent vs 0 percent; p=0.115).