Epidural failure rate using a standardised definition

Abstract

Introduction: There is no globally-accepted definition of epidural failure; this leads to wide differences in reported failure rates. A definition of epidural failure was standardised using a modified Delphi approach involving senior obstetric anaesthetists in the UK. Using this definition, epidural failures were calculated in our institution.

Methods: Following clinical governance approval, anonymised data from 1521 epidurals inserted between September 2010 and December 2011 were collected from our database. Details included pain relief 45 min from the start of the procedure, accidental dural puncture, epidural re-siting, maternal satisfaction, time of insertion and positioning for insertion.

Results: The overall failure rate was 23%. Individual failure rates for trainees were: Year 2, 26.8%; Year 3, 26.3%; Year 4, 21.4%; Year 5, 25%; Year 6, 18.5%; and Year 7, 13.5%. Epidural re-site rates for trainees were: Year 2, 6.5%; Year 3, 3.5%; Year 4, 4%; Year 5 and above, 1.5%. Cervical dilatation, time of day and position for insertion did not have a statistically significant association with the failure rate. However, the failure rate of the Year 2, Year 3, and Year 4 trainees was significantly higher when compared to that of Year 5 and above. The re-site rate was statistically higher for Year 2 and Year 4 trainees when compared to those of Year 5 and above. The accidental dural puncture rate was statistically higher among Year 3 trainees when compared to Year 5 and above.

Conclusion: The study identified epidural failure rates using a standardised definition. This information could be used to guide training decisions and to support doctors during their training period.

Keywords: Epidural analgesia; Failure rate; Training.