Effectiveness of Liposomal Bupivacaine Transversus Abdominis Plane Block in DIEP Flap Breast Reconstruction: Randomized Controlled Trial

Background: Transversus Abdominis Plane (TAP) blocks improve pain control and reduce narcotic medication requirements in various surgical procedures. Liposomal bupivacaine may provide more sustained analgesia. This study compares pain related outcomes between standard bupivacaine and liposomal bupivacaine TAP blocks after autologous breast reconstruction. Methods: Prospective single-center, single-blinded, randomized controlled trial between March 2021 and December 2022. DIEP flap breast reconstruction patients in a standardized Enhanced Recovery After Surgery (ERAS) pathway were randomized to receive intraoperative TAPs with either bupivacaine / epinephrine (control) or liposomal bupivacaine / bupivacaine / epinephrine (experimental). Primary outcome was postoperative narcotic medication requirements, with secondary outcomes of pain scores, length of stay (LOS), and narcotic medication refills. Results: 117 patients met inclusion criteria (59 control, 58 experimental). Patient demographics, comorbidities, breast pathologic variables, surgery laterality and immediate versus delayed reconstruction status were equivalent between groups. Control group had significantly higher average pain scores postoperatively (4.3 vs. 3.6, p=0.004). However, there were no significant differences in mean narcotic use (66.9 MME vs 60.2 MME, p=0.47). Both LOS and postoperative narcotic prescription refills were equivalent between groups (2.1 vs 2.2 days, p = 0.55, 22% vs 17.2%, p=0.52). Conclusion: Addition of liposomal bupivacaine to standard bupivacaine TAP block mixture in a standardized ERAS protocol did not demonstrate a significant reduction in postoperative narcotic requirements after DIEP flap breast reconstruction compared to standard bupivacaine alone. Patient-reported pain scores, however, were lower among liposomal bupivacaine patients after the initial 24 hours postoperatively and consistent with a longer duration of analgesia.