Risk factors for failed conversion of labor epidural analgesia to cesarean delivery anesthesia: a systematic review and meta-analysis of observational trials
Abstract Number: T-15
Abstract Type: Original Research
Background: In this systematic review and meta-analysis we evaluate the evidence for seven risk factors associated with failed conversion of labor epidural analgesia to cesarean delivery anesthesia.
Methods: Multiple scientific literature databases from January 1979 to May 2011 were searched to identify observational trials that evaluated risk factors for failed conversion of epidural analgesia to anesthesia or documented a failure rate resulting in general anesthesia.
Results: Of 1450 trials screened, 13 trials were included for review (n = 8384). Three factors increase the risk for failed conversion: an increasing number of clinician-administered boluses during labor (OR = 3.17, 95% CI 1.83 to 5.46), a greater urgency for cesarean delivery, and a non-obstetric anesthesiologist providing care (OR = 4.56, 95% CI 1.81 to 11.54). Insufficient evidence is available to support CSE versus standard epidural techniques, duration of epidural analgesia, cervical dilation at the time of epidural placement and BMI/weight as risk factors for failed epidural conversion.
Conclusion: The risk of failed conversion of labor epidural analgesia to anesthesia is increased with an increasing number of boluses administered during labor, an enhanced urgency for cesarean delivery, and care being provided by a non-obstetric anesthesiologist. Further high quality studies are needed to more robustly evaluate the many potential risk factors associated with failed conversion of labor epidural analgesia to anesthesia for cesarean delivery.