Epidural analgesia in labour using intermittent doses determined by midwives

Since 1985 midwives have been responsible for choice of drug and timing of epidural top-up doses for women in labour at Flinders Medical Centre. The midwife may choose from one of three different prescribed preparations, namely: bupivacaine 12.5 mg plus pethidine 25 mg, bupivacaine 25 mg, and bupivacaine 50 mg - each made up in a volume of 10 ml. This prospective study examined the incidence of adverse effects and level of patient satisfaction with midwife-managed epidural analgesia. Between 1987 and 1992, 6935 women received midwife-managed epidural analgesia. The pethidine/bupivacaine mixture was generally used for the first dose (75% of women) with a shift towards bupivacaine 25 mg or 50 mg for subsequent top-ups. Sixty-one per cent of women had normal vaginal deliveries, 25% instrumental and 14% caesarean deliveries. The most common side-effects were shivering, hypotension and itch. Shivering occurred following 11% of bupivacaine, and 2% of bupivacaine/pethidine top-ups. Itching was more common after bupivacaine/pethidine (3%) than after bupivacaine (1%). Women reported a high level of satisfaction with the overall experience of childbirth, though this was lower for instrumental and caesarean deliveries than for vaginal deliveries. On the other hand, satisfaction with pain relief provided by the epidural was greater in women who had caesarean or instrumental deliveries. The most commonly cited benefits of epidurals were good pain relief (83%), ability to cope (74%), feeling relaxed (67%), and being aware (60%), while feeling numb (23%) and experiencing severe pain at delivery (17%) were the most common causes of dissatisfaction.