Comparison of Liposomal Bupivacaine for Single-Injection Versus Dual-Injection Thoracic Paravertebral Block on Analgesic Effect After Dual-Microport Thoracoscopic Lobectomy: A Prospective Randomized Controlled Trial.

BACKGROUND

The optimal blockade strategy for thoracic paravertebral block (TPVB) with liposomal bupivacaine (LB) in dual-microport thoracoscopic lobectomy remains unclear. This study evaluated the analgesic efficacy of single-injection versus dual-injection LB in TPVB.

METHODS

This prospective randomized controlled trial enrolled patients undergoing elective dual-port thoracoscopic surgery from June to September 2025. Participants were randomly assigned to either a single-injection group (Group S) or a dual-injection group (Group D). Under ultrasound guidance, Group S received a single 20 mL (266 mg) injection of LB at the thoracic vertebrae 4-5, while Group D received two separate 10 mL (133 mg) injections at the thoracic vertebrae 3-4 and 6-7. The primary outcome was the area under the curve (AUC) of the numerical rating scale (NRS) scores during movement over 72 h postoperatively.

RESULTS

A total of 92 patients were included in this study, with 46 patients allocated to each group. The mean AUC (SD) of NRS scores during movement at 72 h postoperatively for Groups S and D was 148.83 (80.18) and 201.52 (111.99) NRS/h, respectively, with a mean difference of 52.69 (95% CI 12.4 to 93.0, p = 0.011). The incidence of chronic pain at 3 months postoperatively was 19.6% in Group S and 21.7% in Group D (p = 0.798). Generalized estimating equation analysis showed that at rest, Group S had lower NRS scores than Group D at 48 h postoperatively (95% CI -1.4 to -0.2, p = 0.044). During movement, the median NRS scores (IQR) at 24 h for Groups S and D were 3.0 (2.0, 3.0) and 3.0 (2.0, 5.0), respectively, with p = 0.009; at 48 h, the median NRS scores (IQR) were 2.0 (1.0, 3.0) and 2.5 (2.0, 5.0), respectively, with p = 0.014. The median block duration (IQR) for Groups S and D was 7.00 (6.00, 8.00) and 11.00 (9.75, 12.00), respectively, with p < 0.01; the median hospital stay (IQR) was 4.00 (3.00, 4.25) and 4.00 (4.00, 5.00), respectively, with p = 0.045.

CONCLUSION

Single-injection LB in TPVB provides comparable or superior analgesic efficacy while significantly reducing the risk of postoperative complications, making it a preferred analgesic strategy.

TRIAL REGISTRATION: Chinese Registry of Clinical Trials: ChiCTR2500104841.