Efficacy of Erector Spinae Plane Block in Preventing Chronic Pain After Breast Cancer Surgery: A Randomized Controlled Trial.

BACKGROUND

Chronic postsurgical pain (CPSP) affects up to 60% of breast cancer surgery patients, substantially impairing quality of life. Although erector spinae plane block (ESPB) provides effective acute analgesia with superior safety compared to traditional regional techniques, its efficacy in preventing CPSP remains unclear. This trial evaluated whether preoperative single-injection ESPB prevents CPSP following breast cancer surgery.

METHODS

This double-blind, randomized controlled trial enrolled 198 women undergoing unilateral breast cancer surgery in China. Patients received ultrasound-guided ESPB with either 30 mL of 0.5% ropivacaine or placebo at the T5 level before general anesthesia. The primary outcome was CPSP incidence at three months. Secondary outcomes included six-month CPSP incidence, 24-h morphine consumption, postoperative pain scores, and recovery quality.

RESULTS

ESPB did not reduce CPSP incidence at three months [primary outcome: 38/99 (38.4%) versus 43/99 (43.4%); relative risk 0.88, 95% confidence interval (CI) 0.63-1.24, p = 0.470] or six months [23/99 (23.2%) versus 31/99 (31.3%); relative risk 0.74, 95% CI 0.47-1.18, p = 0.202]. However, ESPB reduced 24-hour morphine consumption (median 8.0 mg [interquartile range (IQR) 4.0-12.0] versus 18.0 mg [IQR 14.0-22.0]; median difference -10.0 mg, 95% CI -10.0 to -8.0, p < 0.001) and acute pain scores at rest and during movement (both p < 0.001). One ESPB patient (1/99, 1.0%) experienced transient metallic taste. No serious adverse events occurred.

CONCLUSIONS

Single-injection ESPB does not prevent CPSP after breast cancer surgery. ESPB should be used exclusively for acute postoperative analgesia and cannot be recommended for CPSP prevention.

REGISTRATION: Chinese Clinical Trial Registry (ChiCTR1900027772).