Acute Pain Management after Total Knee Arthroplasty
This thesis presents a body of work aimed at improving the acute pain management of patients after total knee arthroplasty (TKA).
A randomized controlled trial (RCT) of 200 patients found that significant knee pain on movement 24 hours after surgery was reduced with single-injection (OR 0.30; 95% CI 0.12 to 0.74) or continuous (OR 0.21; 95% CI 0.08 to 0.51) femoral nerve block (FNB), compared with patient-controlled analgesia (PCA) opioid. Also, FNB required less opioid compared to PCA.
There were no significant differences in ‘timed up and go’ between the three analgesic groups at all time-points. There was also no significant between group differences in the six-minute walk distance knee flexion range of motion, day achieved independent walking and self-reported physical function.
A Cochrane systematic review pooling RCTs evaluating FNB with non-FNB included 45 eligible RCTs (2710 patients). Meta-analyses demonstrated that FNB resulted in less pain at rest and on movement during the first 72 hours after surgery compared to PCA opioid. At 24 hours, pain at rest was SMD -0.72 (95% CI -0.93 to -0.51), while pain on movement was SMD -0.94 (95% CI -1.32 to -0.55). Additionally, FNB provided similar analgesia compared with epidural or local infiltration analgesia, and continuous FNB provided better analgesia than single-injection FNB.
A patient survey conducted in Singapore (N = 105) and replicated in Australia (N=171) revealed suboptimal management of acute pain after hospital discharge. Many patients experienced moderate to severe pain and had misperceptions on analgesia. Marked differences in pain experience, behaviors and perceptions of analgesics also existed between the two cohorts.
Overall, the thesis provided evidence to guide the choice of postoperative analgesia after TKA. It also
highlighted potential areas for improving pain management following hospital discharge and the need for culturally appropriate pain management strategies.