Analgesic effectiveness of caudal levobupivacaine and ketamine

The addition of 0.5 mg kg−1 S(+)-ketamine to levobupivacaine 0.175% for caudal analgesia for lower abdominal and urological surgery is significantly more effective in providing postoperative analgesia than levobupivacaine 0.15% with 0.5 mg kg−1 S(+)-ketamine or levobupivacaine 0.2%.