Fetal effects of combined spinal-epidural vs epidural labour analgesia: a prospective, randomised double-blind study

Abstract

We have compared fetal heart rate patterns, Apgar scores and umbilical cord gas values following initiation of labour analgesia using either combined spinal-epidural or epidural. One hundred and fifteen healthy women requesting neuraxial analgesia in the first stage of labour were randomly assigned to receive either combined spinal-epidural (n = 62) or epidural analgesia (n = 53). Fetal heart rate traces, recorded for 30 min before and 60 min after neuraxial block, were categorised as normal, suspicious or pathological according to national guidelines. Sixty-one fetal heart rate tracings were analysed in the combined spinal-epidural group and 52 in the epidural group. No significant differences were found in fetal heart rate patterns, Apgar scores or umbilical artery and vein acid-base status between groups. However, in both combined spinal-epidural and epidural groups, there was a significant increase in the incidence of abnormal fetal heart rate patterns following neuraxial analgesia (p < 0.0001); two before compared with eight after analgesia in the combined spinal-epidural group and zero before compared with 11 after in the epidural group. These changes comprised increased decelerations (p = 0.0045) (combined spinal-epidural group nine before and 14 after analgesia, epidural group four before and 16 after), increased late decelerations (p < 0.0001) (combined spinal-epidural group zero before and seven after analgesia, epidural group zero before and eight after), and a reduction in acceleration rate (p = 0.034) (combined spinal-epidural group mean (SD) 12.2 (6.7) h(-1) before and 9.9 (6.1) h(-1) after analgesia, epidural group 11.0 (7.3) h(-1) before and 8.4 (5.9) h(-1) after). These fetal heart rate changes did not affect neonatal outcome in this healthy population.