Applications for local anaesthetics in neonates and infants

Local anaesthetics are popular for alleviating pain from diagnostic and therapeutic procedures. This has obvious psychological benefits for infants, particularly those subjected to repeated procedures. One of the most commonly prescribed topical local anaesthetics is EMLA (a eutectic mixture of 2.5% lidocaine and 2.5% prilocaine). EMLA has long been established for reducing pain associated with venepuncture, intravenous cannulation and superficial skin surgery in children and adults. Until recently, EMLA was not used in neonates due to the theoretical risk of methaemoglobinaemia from the prilocaine metabolite o-toluidine. However, recent studies in neonates have confirmed that blood methaemoglobin was well below the toxic range and not associated with any clinical problems. Further studies have shown that EMLA is an effective analgesic for relieving the pain of venepuncture, arterial puncture and circumcision.