Epidural analgesia for obstetrics: A maternal, fetal, and neonatal study

Abstract

The effect of lumbar epidural (LE) and caudal epidural (CE) analgesia on the fetal heart rate and fetal acid-base status (pH and base excess) of 41 patients was studied during first- and second-stage analgesia in a controlled research delivery room environment. All patients had baseline parameters which made it possible to observe the effects of the epidural technique upon the fetal heart rate, pH, and base excess. Certain neonatal parameters were recorded to evaluate the epidural effect upon the neonate's postdelivery period. These included Apgar scores at 1 and 5 minutes, umbilical cord arterial and venous blood gases, and neonatal blood gases from the umbilical artery in the first hour after birth. There was an increase in late deceleration after epidural block despite segmental analgesia with minimal lidocaine dosages and the absence of hypotension. However, unless second-stage embarrassment or hypotension occurred, no significant deterioration of the acid-base status was noted. The greatest incidence of late deceleration was noted when epidural analgesia was combined with oxytocin. For the few toxemia patients studied, the epidural technique did not prove hazardous. These intrapartum regional analgesic techniques (LE and CE) do not appear to present a hazard to the normal fetus or the fetus at mild risk. Nevertheless, discretion would dictate that these techniques be restricted with evidence of combined antepartum and intrapartum fetal compromise.