Systematic review of high-volume multimodal wound infiltration in total knee arthroplasty.

Pain relief following total knee arthroplasty (TKA) is challenging because early mobilization and rehabilitation are essential for a successful outcome. Postoperative pain can limit recovery, leading to reduced mobility and prolonged hospitalization. There are potential benefits of infiltrating high volumes of local anesthetics around the soft tissues of replaced hip and knee joints. The risk of systemic toxicity is minimized with diluted local anesthetic solution, which also allows a high volume to be used. One of the principal advantages is that analgesia agents are administered intraoperatively by the surgeon, thereby minimizing the need for additional invasive procedures. The authors conducted a systematic review to evaluate whether high-volume multimodal wound infiltration reduces pain and opiate intake while enhancing early rehabilitation and discharge when used in patients undergoing TKA. Only randomized controlled studies were included. Although better pain relief in the immediate postoperative period with wound infiltration is gained after TKA, there is no definite evidence that this leads to a reduction in opiate consumption, the achievement of early milestones, or a reduction in hospital stay. The roles of individual agents in achieving pain relief and the use of percutaneous wound catheter for postoperative doses are also unclear. There are few reports of complications, including falls and delayed mobilization, when femoral nerve blocks are used. Wound infiltration analgesia should be used at the preference of the surgeon and anesthetist provided regular review of their practice is undertaken to identify any untoward side effects. Further randomized trials with sufficient sample size comparing each outcome, including pain scores, opiate consumption, and length of hospital stay, should be undertaken.