Effect of Ropivacaine With Lidocaine on Postoperative Analgesia for Knee Arthroscopy:A Randomized,Double-blind,Placebo-controlled Trial

Objective To evaluate the analgesic effect of intra-articular ropivacaine with lidocaine. Methods A double-blind randomized controlled trial was conducted. Ninety patients receiving selective knee arthroscopy were randomized into three groups of 30 patients. At the end of the operation, before the release of the tourniquet, an intra-articular injection was administered to each patient through arthroscope, in accordance with their random allocation: 0.9% normal saline (normal saline group); 100 mg ropivacaine (ropivacaine alone group) and 100 mg ropivacaine and 100 mg 2% lidocaine (ropivacaine with lidocaine group). Pain intensity was assessed after the operation using the 100-mm visual-analog scale (VAS), and the amount of supplemental analgesics used within the following 24 hours were recorded. Results The VAS scores of 2 hours postoperatively at rest, and 1, 2, 4, and 8 hours postoperatively at motion, were significantly higher in the normal saline group than in ropivacaine alone group (P0.05). The VAS scores 0.5, 1 and 2 hours postoperatively at rest, and at the awaking moment, 0.5, 1, 4, 8, and 24 hours postoperatively at motion, were significantly higher in the normal saline group than in ropivacaine with lidocaine group (P0.05). Conclusion Intra-articular ropivacaine can reduce a patient’s pain after operation. The combination of lidocaine with intra-articular ropivacaine can reduce the patient’s pain severity immediately after the operation and achieve an early analgesic effect.