Background: Caudal blocks have been shown to reliably block dermatomes below the level of the umbilicus (T10–S5) in children <20 kg (∼6 yr of age). Caudal epidural anaesthesia involves accessing the epidural space through the sacrococcygeal ligament via the sacral hiatus at the base of the sacrum. The aim of this study was to compare the effects of ropivacaine and bupivacaine for caudal anaesthesia in children undergoing lower abdominal surgery