Paper #15 - Liposomal bupivacaine inferior to indwelling interscalene nerve block for post-operative pain control in shoulder arthroplasty: a prospective randomized controlled trial

Abstract

Introduction: Pain management following shoulder arthroplasty can include several strategies including peripheral nerve blocks, subacromial/intraarticular injections, and patient controlled anesthesia among others. Local infiltration of liposomal bupivacaine (LB) has demonstrated efficacy in other surgical settings with the potential to avoid complications unique to peripheral nerve blocks. The purpose of this study was to compare LB versus indwelling interscalene nerve blocks (IINB) for postoperative pain control as assessed by pain scores and opiate medication consumption. Materials: This is a prospective, randomized study of 83 consecutive patients that underwent anatomic and reverse total shoulder arthroplasty. 36 patients were randomized to receive LB and 47 patients received an IINB. Postoperative VAS pain levels, opiate consumption as measured with oral morphine equivalents (OME), length of hospital stay, and postoperative complications were recorded throughout hospital admission. Results: Patients that received LB reported higher VAS pain scores immediately postoperative in the post-anesthesia care unit (PACU) (7.25 versus 1.91) as well as the remainder of postoperative day 0 (4.99 versus 3.20). VAS scores remained higher for the remainder of admission however did not reach statistical significance. Opiate consumption was also higher amongst the LB cohort in the PACU (31.79 versus 7.47), on POD 0 (32.64 versus 15.04) and for the total hospital admission (189.50 versus 91.70). Similar complication numbers were noted between groups and length of stay was not statistically different. Conclusion: Use of an indwelling interscalene nerve block provides superior pain management in the immediate postoperative setting as demonstrated by decreased narcotic medication consumption and lower subjective pain scores.