In praise of the epidural space for analgesia in neonates

Epidural analgesia in neonates is now an accepted technique for intraoperative and postoperative pain management in major paediatric centres (1–3). However, its use still creates controversy and discussion. The potential benefits of the intervention must be weighed against the ability of an institution to perform and manage the technique safely. This review will concentrate on the advantages of epidural analgesia in neonates, making recommendations for safe practice, and outline the disadvantages of continuous intravenous morphine infusions. Advantages of epidural analgesia IntraoperativelyReduction of MAC for volatile agents Resulting in: • faster and clearer recovery • reduced side effects which may be associated with higher concentrations of volatile agents • reduced need for muscle relaxants (4) Reduction in postoperative ventilation Epidural analgesia has been shown to be especially suited for specific neonatal conditions such as oesophageal atresia (5), Nissens fundoplication (6) and repair of congenital diaphragmatic hernia (7), particularly in reducing the need for postoperative ventilation. Even if ventilation is required, this period is shorter and less problematic than if opioids are employed (8). The degree of muscle relaxation provided by epidural analgesia will facilitate the reduction of gastroschisis or exomphalos (9). Epidural analgesia can also provide excellent pain relief following thoracic surgery (10). Decrease in stress response The stress of surgery is known to result in compromise of the cardiovascular system, protein metabolism and the immune system, all of which may have significant detrimental effects on the high-risk neonate (11). Epidural analgesia has been demonstrated to reduce this stress response (12), whereas the use of morphine, with its immunosuppressive effect, would amplify this. Haemodynamic stability Epidural analgesia is associated with haemodynamic stability, whereas anaesthesia, with parenteral analgesics, often results in a rise in blood pressure compared. There is also some evidence that bleeding is reduced and operative times are shorter with regional anaesthesia (13). Postoperatively Epidural analgesia decreases, or indeed, removes the need to administer opioid analgesia, thereby reducing the incidence of postoperative respiratory complications. Not only is this safer for the child, it also allows the child to be nursed in ward areas, once adequate education of nursing staff has occurred (3). Gastric function rapidly returns to normal when epidural analgesia is used. This facilitates the re-establishment of feeding and earlier discharge (14). The lack of sedation associated with epidural analgesia enables the parents to be actively involved in the care of their child, thereby increasing parental satisfaction. Economics The use of epidural analgesia produces cost savings for hospitals: • faster discharge • reduced Intensive care stay • efficient use of ward nurses time Safety of regional analgesia in children The complication rate of epidural analgesia in neonates is low. However, there are a number of recommendations that should be followed: (a) the technique should be used only when clinically indicated, nerve blocks are safer than central techniques (15) (b) the technique should be restricted to experienced practitioners. minimising the number of attempts required to achieve successful catheter placement. (c) there should be no contraindications to the technique (d) if possible a caudal catheter technique is safer than a lumbar or thoracic approach (e) loss of resistance techniques using saline are safer than those employing air (f) safer epidural delivery systems should be used (g) utilisation of newer local anaesthetic solutions, i.e. Ropivacaine (3,16), and Chirocaine (h) adherence to the dose recommendations (17) (i) to use epidural infusions for less than 48 hours (18) (j) staff need to be thoroughly educated and assessed to enable them to effectively care for children receiving epidural analgesia Is it safe to use regional analgesia in neonates? There are no studies of complications of regional analgesia in neonates, information can only be derived from studies including older children. The studies by ADARPEF, both retrospective and prospective, demonstrated a low incidence of complications in children. The retrospective study (19) described five tragedies out of 10 000 patients following regional analgesia. The prospective study (15) described 23 incidents in 15 000 central blocks. This incidence is similar to that found in a US study of 15 000 caudal blocks. There is also evidence that bacterial colonisation of caudal or lumbar epidural catheters is not significant for up to 48 hours following the start of the infusion (20).