Abstract: AIM: To observe the efficacy and safety of ropivacaine supplemented with midazolam for sacral block in pediatric operation.METHODS: 40 cases of patients aged 1-6 years old, who were going to be operated in hypogastrium, perineum and lower limb, were randomly and double-blindly divided into four groups with ten cases each:control group (bupivacaine 2.5 mg/kg), low dosage group (ropivacaine 2.5 mg/kg), middle dosage group (ropivacaine 3.5 mg/kg) and high dosage group (ropivacaine 5.0 mg/kg).Sacral block was performed after induction of inhalation anaesthesia with sevoflurane.Sedation was induced by midazolam (0.2mg/kg) administered through mainline 5 min before the surgical procedure.RESULTS: In a certain dosage range, ropivacaine supplemented with midazolam anesthesia for sacral block showed a slight influence on diastolic blood pressure, mean arterial pressure, heart rate and pulse oxygen saturation. Those parameters remained in the physiological normal range, though they dropped slightly during the operative period.Compared with bupivacaine group, the postoperative analgesic period was similar in the high and middle ropivacaine groups, while it was shorter in lowr opivacaine group.There was no significant adverse effect in all groups except for operative stretch reflex and postoperative vomiting in individual patients.CONCLUSION: Ropivacaine supplemented with midazolam anesthesia for sacral block has a slight influence on emodynamics, prolongs the postoperative analgesic period, and shows less adverse effect.

Key words: ropivacaine, midazolam, pediatric anesthesia, sacral block, safety