Abstract / Summary
Background: Erector spinae plane block (ESPB) and modified pectoral nerve block (PECS-II) are being increasingly used to control pain following breast surgeries. However, evidence comparing their effects on postoperative analgesia and surgical stress response is limited. The current study compared analgesic efficacy and surgical stress response attenuation of ESPB and PECS-II in patients undergoing modified radical mastectomy (MRM).
Methods: In this prospective, randomised, comparative study, 42 patients undergoing elective MRM were randomly divided to receive either ESPB or PECS-II. Both groups received 30 mL of 0.2% ropivacaine with 0.5 μg/kg dexmedetomidine after induction of general anaesthesia (GA). The primary outcome was time to first rescue analgesia requirement. Secondary outcomes were postoperative numerical rating scale (NRS) scores, rescue analgesic consumption, intraoperative fentanyl requirement, serum cortisol, interleukin-6 (IL-6) and neutrophil-to-lymphocyte ratio (NLR), patient satisfaction and block-related complications.
Results: The mean time to first rescue analgesia was significantly larger in the PECS-II group than in the ESPB group (9.05 ± 1.12 h vs 6.95 ± 1.16 h; p < 0.001). Patients receiving PECS-II had lower 24-h diclofenac (114.3 ± 38.4 mg vs 146.4 ± 16.4 mg; p = 0.002) and tramadol consumption (7.1 ± 17.9 mg vs 23.8 ± 25.6 mg; p = 0.021). NRS scores were lower in the PECS-II group at 6 h postoperatively (p < 0.001). Intraoperative fentanyl requirement was comparable between the two groups (p = 0.133). Postoperative serum cortisol (363.48 ± 41.79 vs 495.95 ± 52.20 nmol/L), IL-6 (14.48 ± 4.39 vs 24.43 ± 6.33 pg/mL) and NLR (4.15 ± 0.55 vs 4.98 ± 0.85) were also lower in the PECS-II group (p ≤ 0.001). Patient satisfaction scores were higher following PECS-II (5.62 ± 0.74 vs 5.05 ± 0.67; p = 0.022). No block-related complications were observed in either group.
Conclusion: PECS-II provided longer postoperative analgesia than ESPB in patients undergoing MRM under GA. Exploratory analyses showed lower postoperative analgesic consumption, lower pain scores at 6 h, lower postoperative stress response markers and higher patient satisfaction with PECS-II. These secondary findings should be considered hypothesis-generating and warrant confirmation in larger, adequately powered studies. Intraoperative fentanyl requirement was comparable between the two groups.
Trial registration: Clinical Trials Registry: CTRI/2024/04/066198.