Ultrasound-guided erector spinae plane block versus serratus anterior plane block for analgesia and respiratory function in patients with multiple rib fractures: a large-sample, single-center, randomized, double-blind, controlled trial.

OBJECTIVE

This large-sample, randomized, double-blind controlled trial directly compared the analgesic efficacy and impact on respiratory function of ultrasound-guided erector spinae plane block (ESPB) versus serratus anterior plane block (SAPB) in patients with unilateral multiple rib fractures.

METHODS

A total of 158 eligible patients were randomized to receive either ESPB (n = 73) or SAPB (n = 85), performed with 0.375% ropivacaine. The primary outcome was the time-weighted area under the curve (AUC) of resting pain Numerical Rating Scale (NRS) scores over 24 h post-intervention. Secondary outcomes included dynamic pain scores, opioid consumption, respiratory function (diaphragmatic excursion, FVC, FEV1), recovery quality (QoR-15), and clinical outcomes.

RESULTS

The ESPB group demonstrated a significantly lower 24-h pain AUC compared to the SAPB group (mean difference -17.78, 95% CI: -21.00 to -14.56, p < 0.001), indicating superior comprehensive analgesia. ESPB also significantly reduced 24-h opioid consumption and improved QoR-15 scores (both p < 0.01). While both groups showed significant within-group improvement in respiratory function parameters, no significant between-group differences were found. Subgroup analysis revealed that the analgesic superiority of ESPB was consistent across different fracture locations but was more pronounced in patients with ≤5 fractures (interaction p = 0.023). Safety profiles and complication rates were comparable.

CONCLUSION

For patients with unilateral multiple rib fractures, ESPB provides significantly better early comprehensive analgesia and reduces opioid requirements compared to SAPB, without compromising safety. ESPB may be considered as a preferred first-line regional analgesic technique, especially for patients with a lower fracture burden.

CLINICAL TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR), Registration No. ChiCTR2300067544.