Risk factors for epidural anesthesia blockade failure in cesarean section: a retrospective study

Abstract

Abstract Background: Epidural anesthesia (EA) is the preferred regional anesthesia technique in pregnant women who require cesarean section for delivery. Failure of EA requires additional sedation or convert it into general anesthesia (GA). It may be hazardous during sedation or GA conversion due to a potentially difficult airway. Therefore, this retrospective study aimed to determine the risk factors for epidural failure during cesarean section anesthesia. Methods: We retrospectively analyzed parturients who underwent cesarean section under EA and catheterization at Chang Gung Memorial Hospital in Taiwan between January 1 and December 31, 2018. Patient data were collected from medical records. EA failure was defined as the administration of any intravenous anesthetic at any time during the cesarean section, converting it into GA or even tube GA. Results: A total of 534 parturients who underwent cesarean section were recruited for this study. Of these, 94 (17.6%) parturients experienced failure of EA during the cesarean section. Compared to the patients with successful EA, those with EA failure were younger (33.0 years vs. 34.7 years) and have received EA previously (60.6% vs. 37%), were parous (72.3% vs. 55%), and had a shorter waiting time (14.9 mins vs. 16.5 mins) (p < 0.05). Younger age (OR 0.91, 95% CI 0.86–0.95), history of epidural analgesia (OR 2.61, 95% CI 1.38–4.94), and shorter waiting time (OR 0.91, 95% CI 0.87–0.97) were estimated to be significantly associated with a higher risk of epidural anesthesia failure. Conclusion: The retrospective study found that parturients with younger age, previous epidural catheterization history, and inadequate waiting time may have a higher risk of EA failure. Previous epidural catheterization increases the risk of EA failure by 2.6-folds compared to those with no catheterization history.