Reports of Investigation Risk factors of inadequate pain relief during epidural analgesia for labour and delivery
Ghislaine Le Coq CRNA,* B6atrice Ducot MD,'f Dan Benhamou MD*
Purpose: To determine the causes of failure of epidural analgesia during labour and delivery. Methods: During six months, pregnant patients receiving epidural analgesia and delivering vaginally were studied prospectively, Bupivacaine 0. 125% was used for the initial bolus dose and subsequent continuous infusion. Top-ups of the same solution were used for inadequate pain relief assessedusing a visual analogue pain score (VAPS) and/or by clinical examination, Inadequate pain relief was defined as the need for z 2 top-ups in addition to epidural infusion and failure during delivery as VAPS 2 30 mm during the expulsion phase. Results: 1009 patients delivered during this period, 596 had epidural analgesia for vaginal delivery of a live infant and data were complete in 456. Inadequate pain relief during labour and during delivery were found in 5.3% and 19.7% of patients. Riskfactors of inadequate pain relief included: inadequate analgesic efficacy of the first dose (Odds ratio: 3.5, P = 0.001) and posterior presentation (Odds ratio: 5,6, P = 0,001). Radicular pain during epidural placement was associated with failure during labour(Odds ratio: 3.9, P = 0.05). Duration of epidural analgesia > six hours (Odds ratio: 9. I, P = 0.001 ) was a risk factor for insuffkient pain relief during labour whereas duration of epidural analgesia < one hour was associated with pain during delivery (Odds ratio: 18.3, P = 0.001). Conclusion: Several obstetrical and epidural-related factors increase the risk of inadequate epidural analgesia. For some, simple changes of practice pattern may lead to improved pain relief.
Objectif : D~terminer les causes d'insuffisance de l'analg&ie p&idurale obst&ricale. M6thodes : Pendant 6 mois, toutes les patientes en travail ayant re~u une analg&ie p~ridurale ont ~t~