Intrapartum Temperature Changes Following the Intravenous Crystalloid Bolus for Epidural Analgesia

Objective: To assess the effect of the intravenous crystalloid bolus given before epidural analgesia on maternal temperature during labour. Multiple studies have demonstrated a hyperthermic trend in parturient women receiving epidural analgesia. This temperature rise may be affected by the pre-epidural intravenous crystalloid bolus. Methods: Intrapartum oral temperatures were recorded in 40 singleton parturient women immediately before and after an intravenous bolus of Ringer's lactate solution (1L at room temperature [21 degrees C]) and at one hour after standardized insertion of an epidural catheter for analgesia. Exclusion criteria included antibiotic administration, chorioamnionitis, and initial maternal temperature above 37.5 degrees C. Group means were compared using the 2-tailed paired Student t test. Results: There was no significant trend towards a decrease in maternal temperature after the crystalloid bolus (mean change -0.07 degrees C, P = 0.33). Similarly, there was no initial trend towards an increased maternal temperature after epidural insertion (mean change + 0.02 degrees C, P > 0.7). Separate analyses using parity, body mass index, and bolus duration as covariates showed that these variables did not affect maternal temperature changes (P >= 0.2). Conclusion: Our study indicates that intravenous infusion of a crystalloid bolus at room temperature before induction of epidural analgesia does not significantly decrease parturient temperature.