Regular intermittent bolus provides similar incidence of maternal fever compared with continuous infusion during epidural labor analgesia

OBJECTIVES: To compare the effects of regular intermittent bolus versus continuous infusion for epidural labor analgesia on maternal temperature and serum interleukin-6 (IL-6) level.

METHODS: This randomized trial was performed in Nanjing Maternity and Child Health Care Hospital, Nanjing, Jiangsu Province, China between October 2012 and February 2014. Either regular intermittent bolus (RIB, n=66) or continuous infusion (CI, n=66) was used for epidural labor analgesia. A bolus dose (10 ml of 0.08% ropivacaine + 0.4 µg·ml-1 sufentanil) was manually administrated once an hour in the RIB group, whereas the same solution was continuously infused at a constant rate of 10 ml·h-1 in the CI group. Maternal tympanic temperature and serum IL-6 level were measured hourly from baseline to one hour post partum. The incidences of fever (>/=38 degree celsius ) were calculated.

RESULTS: The incidence of maternal fever was similar between the 2 groups. There was a rising trend in mean temperature over time in both groups, but no statistical difference was detected between the groups at respective time points; maternal serum IL-6 showed similar changes.

CONCLUSION: Compared with continuous infusion, regular intermittent bolus presents with the same incidence of maternal fever for epidural labor analgesia. Interleukin-6 elevation could be involved in mean maternal temperature increase.