Efficacy of Periarticular Cocktail Injection in Rheumatoid Patients Undergoing Total Knee Replacement.

Abstract

Pain control after total knee replacement (TKR) is of primary importance to joint replacement surgeons to achieve good functional outcome post-surgery. This becomes even more challenging when these major procedures are done in immunocompromised patients like rheumatoid arthritis. Good peri-operative analgesia facilitates early rehabilitation, improves patient satisfaction, and reduces the hospital stay. The adverse effects caused by epidural analgesia or parenteral opioids can be avoided by replacing it with an analgesic cocktail locally. Our prospective study was to evaluate the benefits of a periarticular cocktail injection which was given in rheumatoid patients undergoing bilateral TKR in single sitting with respect to pain and knee motion recovery. Sixty-four rheumatoid arthritis patients undergoing simultaneous primary total knee replacement were included in the study. A total of 128 knees were randomized either to receive a periarticular intra-operative injection containing ropivacaine, fentanyl, clonidine, cefuroxime and epinephrine (Group A) on one knee and to receive plain ropivacaine (Group B) on the opposite knee. The perioperative and post-operative analgesic regimens were standardized. All patients received the same standard analgesia protocol. Visual analog scores for pain, knee range of motion and quadriceps function were recorded on the day of surgery, first post-operative day, second post-operative day, day of discharge, and 2weeks and 6 weeks during follow-up. The need for rescue analgesic requirement and adverse effects to the cocktail injection were also noted during the study period. The patients who received the periarticular cocktail fared better in terms of pain scores and functional recovery. Additional rescue agents used were significantly less at 6h, at 12h, and over the first 24h after the surgery in group A when compared with group B. No cardiac or central nervous system toxicity was observed. Periarticular cocktail injection significantly reduces the requirements for post-operative analgesia and also improves patient satisfaction, with no apparent risks, following total knee arthroplasty in rheumatoid arthritis.