Epidural analgesia compared with peripheral nerve blockade after major knee surgery

Introduction

The aim of this study was to undertake a randomized trial between lumbar continuous epidural analgesia and continuous femoral blockade in adults undergoing major knee surgery, including comparison of analgesic efficacy [1], side effects, patient satisfaction and rehabilitation indices [2].

Methods

We studied 91 patients in 2 years that were randomized into two groups: epidural group (EG) 40 and femoral group (FG) 51. All patients received spinal anesthesia with 1 ml of 1% bupivacaine without a narcotic. The EG received a 5 ml/hour continuous infusion in elastomeric pump with 0.125% bupivacaine and morphine 20 μg/ml. The FG received a 5 ml/hour continuous infusion in an elastomeric pump with 0.125% bupivacaine and tramadol 1 mg/kg/day + ketorolac 30 mg intravenously × 3.

Results

No statistically significant difference was noted between the two groups about pain scores (VAS at rest and on movement), nausea, vomiting, arterial hypotension, morphine consumption, headache, pruritus, patient satisfaction and rehabilitation indices (active knee flexion). A statistically significant difference was noted between the two groups about contralateral analgesia, urinary retention that required bladder catheterization and motor block with major incidence in the EG.

Conclusion

Continuous femoral blockade represents the best balance between analgesia and side effects as a choice of postoperative analgesic technique for major knee surgery, especially as the risk of injury to the neuraxis is negligible. Overall, however, we believe that there is no sufficient evidence that lumbar epidural analgesia should not be used routinely.