The Effect of Duration of Epidural Analgesia on Maternal Fever During Labor† 1102

Abstract

Fever in labor engenders evaluations for neonatal sepsis and may prolong hospitalization for infants. Previous studies have shown that non-infectious fever in labor is related to the use of epidural analgesia (EA). As EA is a popular and fully accepted mode of obstetric pain relief, current obstetrical practice considers fever to be due to long labor or long rupture of membranes with chorioamnionitis rather than long duration EA. We hypothesize:a. long duration EA contributes to fever more than does long labor and b. short duration EA rarely causes fever. Methods: Concurrent data were collected for 150 consecutive full-term labors in primigravid and secundigravid women. Four groups were defined by short( 14hrs) labors (SL and LL, respectively) and short (no EA to 5hrs EA) or long (>5 hrs) EA duration (S-EA and L-EA, respectively). Average peak oral temperature and fever in labor (defined as>100.5°F) were correlated with these four conditions of labor. Other data collected and studied were duration of rupture of membranes, duration of EA until fever, frequency of shivering in labor, cesarean section frequency, use of antibiotics in labor and the outcome for infants. Data were entered into StatView II for analysis. Results: A. Peak oral temperature in labor =Mean °F ± S.E. (mode, range): group S-EA = 99.0 ± 0.09 (98.6, 97.5-101.1), group SL = 99.3 ± 0.14 (98.6, 97.6-104.4), group LL = 100.0 ± 0.18 (99.6, 97.5-103.4), and group L-EA = 100.6 ± 0.19 (100.9, 98-104.4). B. Incidence of fever within the whole sample was 22%, correlating with EA duration (chi sq with continuity correction=29.1, p=.0001) and correlating with labor duration (chi sq with continuity correction= 5.4, p=.02). C. Incidence of fever among combined sub-groups: SL and S-EA=3/56 or 5.3%, LL and S-EA=2/24 or 8.3%, SL and L-EA=7/17 or 41%, and LL and L-EA=17/36 or, 50%.Conclusions: Short duration EA does not contribute significantly to the development of fever in labor whereas long duration EA does, irrespective of length of labor. To avoid maternal fevers in labor and prolonged neonatal hospitalizations with sepsis evaluations, it would be valuable to adjust anesthesia protocols and priorities to assure short duration EA exposures in labor.