Risk factors and peripartum outcomes of failed epidural: a prospective cohort study

Awareness to rate, risk factors, and the associated peripartum outcomes of failed epidural analgesia (FEA) may improve expectations and labor management. We aimed to identify risk factors for FEA and to examine peripartum outcomes associated with failure.

A prospective cohort study conducted between March 2015 and August 2015, at a single university medical center. Laboring women at ≥34 weeks, receiving epidural analgesia, were eligible. Pain was evaluated using a 0-10 cm visual analogue scale (VAS). FEA was defined as VAS score ≥5, 30 min after the loading dose. The primary outcome was to identify risk factors for FEA. In addition, second-stage duration and operative vaginal delivery rate were also examined. Univariate logistic regression and stepwise multivariate logistic regression were performed to estimate the predictors for FEA.

Of all 414 women included, 35 (8.5%) had FEA. Multivariate stepwise logistic regression revealed that fetal head station 1 cm above the ischial spines (p = 0.002, adjusted OR 5.4, 95% CI 1.9-16.0), oxytocin use (p = 0.026, adjusted OR 2.8, 95% CI 1.1-6.8), and seniority of the anesthesiologist (p = 0.046, adjusted OR 0.97, 95% CI 0.93-0.99) at epidural insertion were found as significant variables associated with FEA. Second-stage duration and operative vaginal delivery rate did not differ significantly between women with failed and successful epidural.

Higher fetal head station and oxytocin use may be associated with higher failure rate. Labor outcomes related to epidural use, occurred at comparable rates, among women with failed and successful epidural.