Comparison of Saphenous Nerve Block and Oral Oxycodone for Postoperative Pain Management in Total Knee Arthroplasty: A Randomized Clinical Trial

Introduction:  Post-operative pain management following total knee replacement (TKA) is crucial. The introduction of some available, inexpensive, and effective methods for post-operative pain management is necessary. Therefore, this randomized clinical trial was done comparing the analgesic effect of an oral low-cost drug (oxycodone) and ultrasound-guided nerve block (saphenous nerve block) to assess the best method for post-operative pain management after TKA surgery.Methods: This single-blind, randomized, controlled, single-center clinical trial was performed from June ۲۰۱۷ to June ۲۰۱۸. There were ۸۰ patients undergoing TKA randomly divided into two groups; group A received a single shot ultrasound-guided saphenous nerve block and, group B took oxycodone which started before and continued every ۶ hours after surgery to control post-operative pain. The pain score by visual analog scale (VAS), nausea- vomiting, and diclofenac use were assessed postoperatively at ۲, ۶, ۱۲, and ۲۴ hours’ post-spinal anesthesia administration. Data were analyzed by SPSS-۲۱, Chi۲, Fishers' exact test, and Mann-Whitney test were used for comparing data between the two groups.Result: The pain intensity according to the visual analog scale at ۲, ۶, ۱۲, and ۲۴ h post-operative was ۱.۲۵±۱.۳۷, ۴.۱۲±۱.۱۱, ۵.۲۵±۰.۸۹, and ۴.۵۷±۰۹۵ in group A, and ۱.۱۰±۰.۹۵۳.۷۷±۰.۹۹, ۴.۰۵±۰.۷۸, and ۲.۹۵±۰.۷۸ in the group B, respectively; this was significantly lower in group B at ۱۲ and ۲۴ hours (P<۰.۰۵). The mean diclofenac use was ۸۷.۰۱±۶۸.۰۲ mg in group B and ۲۶۲.۰۴±۹۲.۰۵ mg in the group A (P<۰.۰۰۱). Also, the incidence of nausea and vomiting was significantly higher in group B compared to group B (P<۰.۰۰۱).Conclusion: Oral oxycodone can control post-operative pain better than saphenous nerve block in the management of post-operative pain and reducing total additional analgesic drug consumption. Although, adverse effects such as nausea and vomiting were lower in saphenous nerve block.

کلیدواژه ها:

Total Knee Arthroplasty ، Post-operative Pain ، Saphenous Block ، oxycodone