Liposomal bupivacaine provides superior pain control compared to bupivacaine with adjuvants in interscalene block for total shoulder replacement: a prospective double-blinded, randomized controlled trial

Abstract

Introduction: Optimal pain control methods after total shoulder arthroplasty (TSA) achieve reduced opioid consumption, shortened hospital stay, and improved patient satisfaction in addition to adequate analgesia. Interscalene brachial plexus block is the gold standard for TSA, yet it typically does not provide pain relief lasting beyond 24 hours. Liposomal bupivacaine (LB) purportedly provides prolonged analgesia, yet it has been minimally explored for interscalene block, and it is significantly more expensive than standard bupivacaine.

Methods: This is a prospective, 2-arm, double-blinded randomized controlled trial. Subjects presenting for anatomic or reverse TSA were randomized in a 1:1 ratio to receive interscalene brachial plexus block with either LB plus bupivacaine (LBB group) or bupivacaine plus dexamethasone and epinephrine (BDE group). The primary outcome was 120-hour postoperative opioid consumption. Secondary outcomes were pain scores up to 96 hours postoperatively, pain control satisfaction, complications, level of distress from block numbness, and hospital stay.

Results: Ninety patients, 45 per group, were included in the intention-to-treat analysis and randomized. Because of withdrawal of consent and loss to follow-up, 40 in each group completed enrollment through postoperative day 60. Total 120-hour postoperative opioid consumption was similar between groups (P = .127), with no differences within 24- or 48-hour time intervals. Postoperative pain scores at 24-48 hours, 48-72 hours, 72-96 hours, and day 60 were significantly lower for the LBB group.

Discussion: LB interscalene brachial plexus block before total shoulder arthroplasty did not reduce 120-hour postoperative opioid consumption but significantly reduced postoperative pain between 24 and 96 hours and at postoperative day 60.

Keywords: Liposomal bupivacaine; interscalene nerve block; local anesthesia; perioperative pain management; postoperative analgesia; regional anesthesia.