Liposome Bupivacaine Femoral Nerve Block for Postsurgical Analgesia after Total Knee Arthroplasty

PAIN MEDICINE Liposome Bupivacaine Femoral Nerve Block for Postsurgical Analgesia after Total Knee Arthroplasty Admir Hadzic, M.D., Harold S. Minkowitz, M.D., Timothy I. Melson, M.D., Richard Berkowitz, M.D., Anna Uskova, M.D., Forrest Ringold, M.D., Janice Lookabaugh, M.P.H., Brian M. Ilfeld, M.D., M.S. ABSTRACT Background: The authors evaluated the efficacy of liposome bupivacaine in a femoral nerve block (FNB) after total knee arthroplasty. Methods: Part 1: subjects received FNB with 20 ml liposome bupivacaine (67, 133, or 266 mg) or placebo. Part 2: subjects were randomized to FNB with liposome bupivacaine 266 mg or placebo. The primary outcome measure was area under the curve of the numeric rating scale score for pain intensity at rest through 72 h (AUC NRS-R 0–72 ) with imputed scores after rescue medication. Results: In part 1, FNB with liposome bupivacaine 266 mg (n = 24) resulted in analgesia similar to that obtained with 133 mg and was chosen for part 2. In part 2, least-squares mean (standard error) AUC NRS-R 0–72 was lower with liposome bupiva- caine 266 mg (n = 92) than with placebo (n = 91; 419 [17] vs. 516 [17]; P