Recent advances in patient-controlled epidural analgesia for labour

PURPOSE OF REVIEW

Patient-controlled epidural analgesia (PCEA) is a relatively new mode of maintenance of labour analgesia. The purpose of this review is to demonstrate that PCEA has several advantages over continuous-infusion analgesia and to discuss recent refinements in the use of PCEA for labour.

RECENT FINDINGS

Early investigations showed that PCEA without background infusion reduced the incidence of motor block and the amount of local anaesthetic needed to produce satisfactory analgesia compared to continuous infusions. Recent studies have shown that the addition of a background infusion to PCEA may be advantageous, depending on the patient population and the rate of the continuous infusion. Both bupivacaine and ropivacaine have been used in PCEA but ropivacaine may be associated with a reduced incidence of motor block in parturients who have epidural analgesia for long periods of time. Of note, very low concentrations of local anaesthetics are required to produce satisfactory analgesia.

SUMMARY

PCEA has proven to be a safe, convenient, and highly effective way to maintain labour analgesia. Parturients appreciate the control they have over the analgesia received throughout labour when this method is used.

Patient-controlled epidural analgesia or continuous infusion: advantages and disadvantages of different modes of delivering epidural analgesia for labour

Patient-controlled epidural analgesia, intermittent top-up and continuous infusion are equally effective in providing epidural pain relief during labour. Patient-controlled epidural analgesia is associated with a significant reduction in hourly dose requirements when compared with continuous infusion, and by transferring the responsibility for epidural top-up, it offers the parturient the psychological benefit of being in control. For these reasons, patient-controlled epidural analgesia may become the method of choice for epidural pain relief during labour. However, the safety of the method needs to be documented more extensively, and the advantage of a reduction in hourly dose requirements needs to be visualized in terms of an improvement in labour or neonatal outcome. Moreover, the optimal dose, drug combination and settings still remain to be determined.

A survey of epidural analgesia for labour in the United Kingdom

A postal survey of obstetric units throughout the UK was conducted to obtain information about the provision of epidural analgesia for labour. Ninety per cent of units offered a 24-h epidural service and the average epidural rate was 24%. The most commonly administered epidural test dose was 3 ml of bupivacaine 0.5% and bupivacaine 0. 25% was most often used as the initial epidural top-up. Continuous infusions of low-dose bupivacaine and opioid mixtures were the most popular method of maintenance epidural analgesia. Twenty-four per cent of units offered combined spinal-epidural analgesia in addition to standard epidural analgesia. Midwives played a prominent role in the administration of epidural bolus top-ups and also in the assessment and maintenance of continuous epidural infusions.

New epidural techniques for labour analgesia: patient-controlled epidural analgesia and combined spinal-epidural analgesia

Epidural analgesia in labour aims to provide high-quality pain relief of rapid onset and prolonged duration, while minimizing both maternal side-effects, particularly impairment of mobility, and impact on the fetus or on the outcome of labour. In conjunction with pharmacological research on spinal analgesics (local anaesthetics, opioids and other drug classes), refinement of new or established drug delivery techniques has allowed progress toward more reliable and improved pain relief at all stages of labour and childbirth, reduced individual drug doses with reduction of unwanted effects and greater safety and enhancement of maternal satisfaction. Patient-controlled epidural analgesia in labour has been in use for almost a decade, although is only now at a stage where its role is well defined and utility can be increased. Combined spinal-epidural analgesia is a more recent refinement which appears to be extremely promising but awaits further investigation.