Analgesic efficacy and safety of erector spinae plane block versus serratus anterior plane block in breast surgery-a meta-analysis and systematic review of randomized controlled trials

Abstract

Background: Mastectomy and breast-conserving surgery are key interventions for breast cancer, a leading cause of cancer-related mortality in women. Many undergoing breast surgery experience postoperative pain compromising their functionality and quality of life. While multiple pain management strategies are available, evidence comparing the erector spinae (ESPB) and serratus anterior plane blocks (SAPB) for improving post-surgical pain management in breast cancer surgery patients is limited. Therefore, we investigated the efficacy and safety of these two regional anesthesia techniques.

Methods: After PROSPERO registration, we systematically searched PubMed, Google Scholar, and Cochrane Library until May 2024. Risk ratios (RR) were calculated for dichotomous outcomes and standard mean differences (SMD) or mean differences (MD) were computed for continuous data. RevMan Review Manager 5.4.1 was used for the data analysis and generation of forest plots as well as funnel plots. The Cochrane Risk of Bias tool 2.0 (18) and Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) guidelines were used to appraise and evaluate the evidence (19).

Results: A total of 9 randomized control trials enrolling 550 patients were included. Static pain scores at 0, 6, 8, 12, and 24 h after surgery, dynamic pain scores computed at 0, 8, 12, and 24 h after surgery and area under the curve (AUC) static pain score at all time points between 0 and 24 h (SMD (HKSJ 95% CI) - 0.27 [- 0.99, 0.45]) did not significantly vary with either plane block. Postoperative morphine consumption in the first 24 h and the number of patients requesting analgesia were significantly greater in those receiving SAPB [MD: - 1.41 (95% C.I. - 2.70, - 0.13), p = 0.03] and [RR: 1.28 (95% C.I. 1.00, 1.63), p = 0.05], respectively. The time to first postoperative analgesic use was significantly greater among those administered ESPB [MD: 1.55 h, (95% C.I. 1.02, 2.09), p < 0.01]. Patient satisfaction scores and the incidence of nausea and vomiting were similar across both groups.

Conclusions: While pain scores with either block are comparable, ESPB reduces postoperative morphine consumption and may be the favorable option in breast cancer patients undergoing surgery.

Keywords: Breast cancer surgery; ESPB; Postoperative pain; Regional anesthesia; SAPB.

Fig. 1

PRISMA flowchart. PRISMA Preferred Reporting Items for Systematic Reviews and Meta-Analyses

Fig. 2

Risk of bias assessment for the included trials using Cochrane risk of bias tool 2.0

Fig. 3

a Forest plot of AUC postoperative pain scores (static) between 0 and 24 h. The SMD estimates for each study are represented by squares, and the lines passing through them represent 95% CI. The diamond represents the overall pooled estimate. b Postoperative pain scores (static) at 24 h (forest plot of sensitivity analysis). SMD standard mean difference, CI confidence interval, IV inverse variance, SD standard deviation, ESPB erector spinae plane block, SAPB serratus anterior plane block

Fig. 4

a Forest plot of 24-h postoperative oral morphine (mg) equivalent consumption. The MD estimates for each study are represented by squares and the lines passing through them represent 95% CI. The diamond represents the overall pooled estimate. b 24-h postoperative oral morphine (mg) equivalent consumption (forest plot for subgroup analysis). c 24-h postoperative oral morphine (mg) equivalent consumption (forest plot for sensitivity analysis in group bupivacaine). MD mean difference, CI confidence interval, IV inverse variance, SD standard deviation, ESPB erector spinae plane block, SAPB serratus anterior plane block

Fig. 5

a Postoperative pain scores (static) at 0 h. b Postoperative pain scores (static) at 0 h (forest plot for sensitivity analysis). c Postoperative pain scores (static) at 6 h. d Postoperative pain scores (static) at 8 h. e Postoperative pain scores (static) at 8 h (forest plot for sensitivity analysis). f Postoperative pain scores (static) at 12 h. g Postoperative pain scores (static) at 24 h. h Postoperative pain scores (static) at 24 h (forest plot for sensitivity analysis). SMD standard mean difference, CI confidence interval, IV inverse variance, SD standard deviation, ESPB erector spinae plane block, SAPB serratus anterior plane block

Fig. 6

a Postoperative pain scores (dynamic) at 0 h. b Postoperative pain scores (dynamic) at 8 h. c Postoperative pain scores (dynamic) at 8 h (forest plot for sensitivity analysis). d Postoperative pain scores (dynamic) at 12 h. e Postoperative pain scores (dynamic) at 12 h (forest plot for sensitivity analysis). f Postoperative pain scores (dynamic) at 24 h. g Postoperative pain scores (dynamic) at 24 h (forest plot for sensitivity analysis). SMD standard mean difference, CI confidence interval, IV inverse variance, SD standard deviation, ESPB erector spinae plane block, SAPB serratus anterior plane block

Fig. 7

Forest plot for number of patients requested analgesia in first 24 h postoperatively. RR relative risk, CI confidence interval, M–H Mantel–Haenszel, SD standard deviation, ESPB erector spinae plane block, SAPB serratus anterior plane block

Fig. 8

a Forest plot for time to request the first dose of postoperative analgesia. b Forest plot for time to request the first dose of postoperative analgesia (sensitivity analysis). MD mean difference, CI confidence interval, IV inverse variance, SD standard deviation, ESPB erector spinae plane block, SAPB serratus anterior plane block

Fig. 9

Forest plot for postoperative satisfaction score. MD mean difference, CI confidence interval, IV inverse variance, SD standard deviation, ESPB erector spinae plane block, SAPB serratus anterior plane block

Fig. 10

a Forest plot for nausea. b Forest plot for vomiting (adverse effects of the blocks). RR relative risk, CI confidence interval, M–H Mantel–Haenszel, SD standard deviation, ESPB erector spinae plane block, SAPB serratus anterior plane block