Postoperative analgesic efficacy of peripheral levobupivacaine and ropivacaine:: A prospective, randomized double-blind trial in patients after total knee arthroplasty

BACKGROUND: Several previous trials have characterized the intra- and postoperative effects of the recently introduced local anesthetics, levobupivacaine and ropivacaine, for a variety of continuous peripheral nerve blocks. METHODS: We compared the analgesic efficacy of levobupivacaine 0.125% versus ropivacaine 0.2% via patient-controlled femoral nerve analgesia after total knee arthroplasty. In a double-blind, randomized, prospective design, 60 patients received femoral infusion with either substance. We analyzed postoperative local anesthetic consumption, pain scores, motor block, and opioid requirements over 72 h. RESULTS: Pain scores, motor block incidence, and opioid requirements were low and not different between the groups. Ropivacaine consumption in milligrams was 67% higher than that of levobupivacaine. CONCLUSIONS: Both levobupivacaine 0.125% and ropivacaine 0.2% provide similar analgesia after total knee arthroplasty with the latter being less potent.