Pectoral I Block Does Not Improve Postoperative Analgesia After Breast Cancer Surgery: A Randomized, Double-Blind, Dual-Centered Controlled Trial.

Background And Objectives: General anesthesia for breast surgery may be supplemented by using a regional anesthetic technique. We evaluated the efficacy of the first pectoral nerve block (Pecs I) in treating postoperative pain after breast cancer surgery.

Methods: A randomized, double-blind, dual-centered, placebo-controlled trial was performed. One hundred twenty-eight patients scheduled for unilateral breast cancer surgery were recruited. A multimodal analgesic regimen and surgeon-administered local anesthetic infiltration were used for all patients. Ultrasound-guided Pecs I was performed using bupivacaine or saline. The primary outcome was the patient pain score (numerical rating scale [NRS]) in the recovery unit 30 minutes after admission or just before the morphine administration (NRS ≥4/10). The secondary outcomes were postoperative opioid consumption (ie, in the recovery unit and after 24 hours).

Results: During recovery, no significant difference in NRS was observed between the bupivacaine (n = 62, 3.0 [1.0-4.0]) and placebo (n = 65, 3.0 [1.0-5.0]) groups (P = 0.55). However, the NRS was statistically significantly different, although not clinically significant, for patients undergoing major surgeries (mastectomies or tumorectomies with axillary clearance) (n = 29, 3.0 [0.0-4.0] vs 4.0 [2.0-5.0], P = 0.04). Morphine consumption during recovery did not differ (1.5 mg [0.0-6.0 mg] vs 3.0 mg [0.0-6.0 mg], P = 0.20), except in the major surgery subgroup (1.5 mg [0.0-6.0 mg] vs 6.0 mg [0.0-12.0 mg], P = 0.016). Intraoperative sufentanil and cumulative morphine consumption up to 24 hours did not differ between the 2 groups. Three patients experienced complications related to the Pecs I.

Conclusions: Pecs I is not better than a saline placebo in the presence of multimodal analgesia for breast cancer surgery. However, its role in extended (major) breast surgery may warrant further investigation.

Clinical Trial Registration: This study was registered at ClinicalTrials.gov, identifier NCT01670448.