Single shot “3-in-1” femoral nerve blockade with 0.25% or 0.375% levobupivacaine provides similar postoperative analgesia for total knee replacement

Aim: To compare postoperative analgesia provided by single shot “3-in-1” femoral nerve blockade using 0.25% or 0.375% levobupivacaine in preceding with spinal anesthesia for unilateral total knee replacement surgery. Materials and methods: Forty consenting patients undergoing unilateral total knee arthroplasty were included in this prospective randomized study. Spinal anesthesia was achieved with 15 mg plain bupivacaine at the L3-4 or L4-5 interspace. After resolution of the spinal anesthesia, patients were randomized into 2 groups: “3-in-1” femoral nerveblocks were performed using 30 mL of 0.25% levobupivacaine (Group 1, n = 20) or 0.375% levobupivacaine (Group 2,n = 20). Pain was assessed by visual analogue scale (VAS). The total morphine consumption and the side effect profile were compared during the postoperative period. Results: There were no significant differences between the 2 study groups with respect to characteristics or intraoperative variables. Furthermore, sensory block periods and time to first pain sensation, VAS, and morphine consumption for 24h (Group 1: 19.7 ± 9.2, Group 2: 20.6 ± 12.1 mg) were similar. Pain scales and range of motion during rehabilitation period and side effects were also comparable.Conclusion: Our results indicate that the augmenting concentration did not influence the clinical outcome when single shot “3-in-1” femoral nerve block was performed with 0.25% or 0.375% levobupivacaine in total knee arthroplasty.