Liposomal Bupivacaine Versus Continuous Nerve Block: Liposomal Bupivacaine May be Non-inferior and More Cost Effective

Background Regional anesthesia with adductor canal block has become the standard of care for pain management after total knee arthroplasty (TKA). We hypothesized that liposomal bupivacaine (LB) may be noninferior to continuous nerve block with a pain pump in terms of average pain scores, 30- and 90-day readmissions, and emergency department (ED) visits while reducing cost. Methods A retrospective chart review was performed on primary TKA patients from 2015 to 2020 by 23 orthopaedic surgeons at a single institution. The inclusion criteria was treatment with LB or a pain pump, and exclusion criteria was receipt of both anesthetics and revision surgery. A total of 2,378 patients met the inclusion criteria with 1,640 patients treated with LB and 738 treated with the pain pump. Demographic differences were not statistically significant. Primary outcomes were average pain scores, 30- and 90-day readmissions, and ED visits. Secondary outcomes were average milligram morphine equivalents per admission, hospital lengths of stay , and costs. Results There was no significant difference in pain scores on postoperative days 0, 1, 2, or 3 (P = .77, .86, 0.08, and 0.40, respectively), 30- or 90- day readmissions (P = .527 and P = .374), ED visits (P = .129 and P = .108), milligram morphine equivalents utilizations (P = .194), or average hospital LOS (P = .348). We estimated a potential cost savings of $95 per patient and $155,800 over the course of the study. Conclusion LB was found to be noninferior to a pain pump, and the transition to this medication was associated with cost savings.