Ultrasound-guided erector spinae plane block compared to serratus anterior muscle block for postoperative analgesia in modified radical mastectomy surgeries: A randomized control trial.

Background And Objectives: The present study was undertaken to compare the analgesic efficacy of erector spinae plane (ESP) block with serratus anterior muscle (SAM) block in patients undergoing modified radical mastectomy (MRM). We hypothesized that ESP block would provide better postoperative pain relief than SAM block following MRM.

Methods: Eighty American Society of Anaesthesiologists (ASA) I-II adult females, scheduled for MRM, were randomly allocated to receive either ultrasound-guided ipsilateral single-shot ESP or SAM block after induction in the respective planes, using 20 ml of 0.25% ropivacaine. Both the groups received postoperative intravenous patient-controlled analgesia (IV-PCA) (morphine) for 24 h. The primary outcome was to assess pain severity using a visual analogue scale (VAS) score. Postoperative 24-h opioid consumption, time to first opioid analgesia, hemodynamic variables, total dose of antiemetics, and safety profile of both the blocks were also evaluated. Data analysis was carried out using Statistical Package for the Social Sciences version 21.0 (SPSS Inc. Chicago, Illinois, USA).

Results: VAS scores were lower in the ESP block group, at rest and on movement, and the difference was statistically significant ( < 0.05). Postoperative morphine consumption was also significantly less in patients receiving ESP block as compared to SAM block (3.13 ± 1.44 mg vs 4.33 ± 1.69 mg; = 0.001). The time to first analgesia request was significantly prolonged in the ESP group as compared to the SAM group (9.58 ± 4.11 h vs 6.46 ± 2.95 h; = 0.001). No major side effects were observed in any of the study groups.

Conclusions: ESP block provides better analgesia as compared to SAM block after MRM.

Clinical Trial Registration Number: CTRI/2019/03/018067.