Prophylactic acetaminophen does not prevent epidural fever in nulliparous women: a double-blind placebo-controlled trial

Abstract

Objective: Epidural analgesia is associated with a four- to five- fold increase in noninfectious maternal fever in nulliparous women. Fever prophylaxis may safely reduce both unnecessary neonatal sepsis evaluations and the potential effect of fever on the fetus.

Study design: We performed a randomized double-blind placebo-controlled study. Immediately after epidural placement, full-term nulliparas with a temperature of <99.5 degrees F received acetaminophen 650 mg or placebo, per rectum, every 4 hours. Tympanic membrane temperatures were measured hourly. Our power to detect an effect of acetaminophen treatment on maternal temperature over time was 90%.

Results: In all, 21 subjects were randomized to each arm. Treatment with acetaminophen did not impact maternal temperature curves. Fever >100.4 degrees F was identical in the acetaminophen and placebo groups (23.8%, p=1.0). Neonatal surveillance blood cultures did not reveal occult infection.

Conclusions: Acetaminophen prophylaxis prevented neither maternal hyperthermia nor fever secondary to epidural analgesia, suggesting that the mechanism underlying fever does not include centrally mediated perturbations of maternal thermoregulation.