Ropivacaine 0.25% compared with bupivacaine 0.25% by the caudal route

We compared in a randomized double-blind study, the postoperative analgesia and degree of motor block produced by the new local anaesthetic ropivacaine, with bupivacaine, for caudal anaesthesia in children. Eighty children, 2-5-years-old, ASA I, received one of two local anaesthetics; either ropivacaine 0.25% (1.0 ml.kg(-1)) or bupivacaine 0.25% (1.0 ml.kg(-1)). They were sedated with a continuous infusion of propofol (200 mu g.kg(-1).min(-1)). The lungs were ventilated with a mixture of 50% nitrous oxide with oxygen. 60 min after local anaesthetic injection, and every 60 min, the extent of the motor block in the recovery room was scored as 1-3, according to a modified Bromage scale. Adverse events and the time to the first analgesic requirement were reported. Patients in the two groups did not differ with respect to age, weight and height. There were no differences in heart rate and arterial pressure between the two groups (P>0.05). No adverse events were observed. The ropivacaine group showed a shorter duration of motor block than the bupivacaine group (P<0.05). The first postoperative analgesic requirement was a mean (SD) of 5 h +/- 4.32 after the operation in the ropivacaine group and 5 h +/- 3.81 for the bupivacaine group. These findings suggest that caudal anaesthesia with ropivacaine 0.25% in paediatric patients can be effective, with less motor blockade in the postoperative period.