DOES EPIDURAL ANALGESIA CAUSE DYSTOCIA

Study Objective: To analyze the effects of epidural analgesia for labo r when dystocia occurs. Design: Retrospective cohort study. Setting: A cademic health center. Patients: 641 low risk, nulliparous women in sp ontaneous labor. Interventions: 406 (63%) women received epidurals ana lgesia nad 253 (37%) did not. Sixty women (9.4%) required an abdominal delivery for dystocia. Measurements and Main Results: Women receiving epidural analgesia were more likely to be white, receive care from an attending physician, need labor augmentation, and deliver a heavier i nfant. Multivariate analysis identified five variables predictive of d ystocia and abdominal delivery: pitocin augmentation odds ratio (O.R.) = 3.9 (2.0 to 7.6), duration of labor more than 20 hours O.R. = 2.4 ( 1.3 to 4.4), high epidural dose O.R. = 2.2 (1.2 to 4.1), birthweight o ver 4,000 grams O.R. = 2.0 (1.0 to 4.2), and early placement of epidur al O.R. = 1.9 (1.0 to 3.5). Repeating the regression after excluding t he 20 women who developed abnormal labor prior to epidural placement ( 18 of 20 women had protracted dilation) demonstrated that pitocin augm entation O.R. = 4.0 (1.8 to 4.), high epidural dose O.R. = 3.0 (1.9 to 6.2), duration of labor greater than 20 hours O.R. = 2.7 (1.3 to 5.7) , and birthweight over 4,000 grams O.R. = 2.1 (0.9 to 4.8) were associ ated with dystocia. Conclusion: Epidural analgesia appears to be a mar ker of abnormal labor rather than a cause of dystocia. High concentrat ion anesthetics and epinephrine should be avoided, as they may influen ce labor. Randomized, controlled trials of this technique will be diff icult to do: our work reassure patients and their clinicians that epid ural analgesia does not adversely affect labor. (C) 1998 by Elsevier S cience Inc.