A superiority study of the analgesic efficacy of ultrasound-guided erector spinae plain block compared to serratus anterior plain block using bupivacaine-dexamethasone for modified radical mastectomy

Abstract

Background This trial compared the preemptive analgesic efficacy of erector spinae plain block (ESPB) and serratus anterior plain block (SAPB) for patients scheduled for modified radical mastectomy. Methods This randomized, controlled, double-blinded study embraced 40 patients aged 20 to 70 years undergoing modified radical mastectomy. Patients were randomly allocated into two equal groups: Group I (n=20): received SAPB, Group II (n=20): received ESPB. Both groups were injected with 30 ml of 0.25% bupivacaine and 8 mg dexamethasone. The time of the first analgesic request was the primary outcome measure while the secondary outcome measures were total fentanyl consumption (intraoperative and postoperative within 24 h), visual analogue scale (VAS) values within 24 h post-operatively at rest and ipsilateral arm movement and side effects related to the received blocks. Results This study illustrated that the median [interquartile range (IQR)] time of the first analgesic request was significantly longer in ESPB group [720(600–720) minute] than SAPB group [600(600–720) minute], P=0.04. The total median fentanyl consumption was significantly higher in SAPB group than ESPB group [0(40.000–80.000) vs. 0(0–0)], P=0.004 intraoperatively and [42.5(40–82.5) vs. 40(40–40)], P=0.005 post-operatively. VAS values at rest were significantly lower in ESPB group than SAPB group [immediate P=0.009, 2 h P=0.004, 6 h P=0.007, 12 h P=0.005, 24 h P=0.002] and values at ipsilateral arm abduction were significantly lower in ESPB group than SAPB [immediate P=0.004, 2 h P=0.02, 12 h P=0.009, 24 h P=0.023]. No side effects were detected in both groups. Conclusion ESPB provides superior analgesia to SAPB in patients undergoing modified radical mastectomy.