Liposomal bupivacaine vs ropivacaine for ultrasound-guided transversus abdominis plane block after laparoscopic radical colectomy: Propensity score-matched retrospective study

Abstract

BACKGROUND

Laparoscopic radical resection for colon cancer is associated with postoperative pain, opioid-related adverse events, perioperative immunosuppression, and inflammatory activation. Transversus abdominis plane block (TAPB) is an important component of multimodal analgesia; however, the analgesic duration of ropivacaine remains limited. Liposomal bupivacaine may provide prolonged analgesia, but comparative evidence in this population is limited.

AIM

To compare the effects of liposomal bupivacaine vs ropivacaine for ultrasound-guided TAPB on postoperative analgesia, anesthetic emergence, early recovery, immune-inflammatory biomarkers, delirium, and safety in patients undergoing laparoscopic radical colectomy.

METHODS

This retrospective propensity score-matched cohort study initially included 215 patients. After applying eligibility criteria and 1:1 propensity score matching, 130 patients (65 per group) were analyzed. Group A received TAPB with ropivacaine (100 mg), whereas Group B received liposomal bupivacaine (266 mg). The primary endpoint was postoperative resting pain intensity over 48 hours, assessed using visual analog scale. Secondary endpoints included anesthetic emergence and early recovery parameters, rescue analgesia, patient-controlled intravenous analgesia demands, immune cell subsets, inflammatory cytokines, delirium, and adverse events. Longitudinal outcomes were analyzed using linear mixed-effects models with a random intercept for matched pairs and Bonferroni correction for multiple post-hoc comparisons.

RESULTS

After propensity score matching, baseline characteristics were well balanced. Group B had significantly shorter times to spontaneous respiration recovery, eye opening, extubation, orientation recovery, and post-anesthesia care unit stay. Group B also had a lower 48-hour rescue analgesia rate (10.77% vs 26.15%, P = 0.002) and fewer effective and total patient-controlled intravenous analgesia demands. Visual analog scale scores showed a significant time × group interaction, with lower pain scores in group B at 2 hours, 6 hours, 12 hours, 24 hours, and 48 hours postoperatively. Immune and inflammatory markers showed significant time, group, and interaction effects. Group B had higher CD3+ T-cell percentages and CD4+/CD8+ ratio at 24 hours and higher natural killer cell percentages at 24 hours and 72 hours. Levels of C-reactive protein, C-X-C motif chemokine ligand 8, tumor necrosis factor-α, and interleukin-1β were significantly lower in group B. No significant between-group differences were found in postoperative delirium (P = 0.083 at 24 hours; P = 0.157 at 72 hours) or overall adverse event rates (P = 0.317).

CONCLUSION

In patients undergoing laparoscopic radical colectomy, liposomal bupivacaine TAPB was associated with improved analgesic outcomes, faster anesthetic emergence, and more favorable immune-inflammatory biomarker profiles compared with ropivacaine. However, because the compared doses were not equipotent and the design was retrospective, causal inference is limited and differences may partly reflect dose disparity rather than the liposomal formulation itself.

Keywords: Liposomal bupivacaine; Ropivacaine; Transversus abdominis plane block; Laparoscopic radical colectomy; Postoperative analgesia; Immune-inflammatory response

Core Tip: This retrospective propensity score-matched cohort study compared liposomal bupivacaine with ropivacaine for transversus abdominis plane block in patients undergoing laparoscopic radical colectomy. Liposomal bupivacaine was associated with lower pain scores, reduced rescue analgesia and patient-controlled analgesia demands, and faster anesthetic emergence over 48 hours. It was also associated with attenuated postoperative immune suppression and inflammatory activation, without significant differences in delirium or adverse events. However, the two regimens were not dose-equivalent, which may have influenced the observed differences.