Comparison of racemic bupivacaine, ropivacaine, and levo-bupivacaine for pediatric caudal anesthesia: Effects on postoperative analgesia and motor block

Background and objectives: To compare ropivacaine, levo-bupivacaine, and racemic bupivacaine for caudal blockade in children. Methods: Using a prospective observer blinded design, 60 sevoflurane anesthetized children (I to 7 years) undergoing minor subumbilical surgery, were randomized to receive a caudal block (1 mL/kg) with either ropivacaine 0.2%, racemic bupivacaine 0.25%, or levo-bupivacaine 0.25%. Postoperative analgesia (number of patients needing supplemental analgesia as defined by an objective pain score [OPS] score of greater than or equal to 5; time to first analgesic demand) during the first 24 postoperative hours was chosen as the primary end-point. Early postoperative motor block (3-point scale) was assessed as a secondary end-point, Results: All blocks were judged to be clinically successful based on the presence of adequate intraoperative and early postoperative analgesia. An OPS score greater than or equal to 5 was found in 5/20 patients in each study group. No difference regarding the time to first analgesic demand was found between the study groups. The use of ropivacaine (P =.02), but not levo-bupivacaine (P =.18), was found to be associated with less motor block during the first postoperative hour compared with racemic bupivacaine. Conclusion: All 3 investigated local anesthetics were found to be clinically comparable despite the slight reduction of early postoperative motor block associated with the use of ropivacaine.