A systematic review and meta-analysis of the effects of general anesthesia combined with continuous paravertebral block in breast cancer surgery and postoperative analgesia

Gland Surg. 2021 May;10(5):1713-1725. doi: 10.21037/gs-21-272.

Abstract

Background: This study aimed to compare the effects of general anesthesia (GA) combined with continuous paravertebral block (CPVB) in breast cancer surgery via systematic review and meta-analysis, in order to provide a theoretical basis for the clinical use of CPVB surgical analgesia.

Methods: A search of the PubMed, Embase, Medline, Ovid, Springer, and Web of Science databases was conducted to screen clinical trials on GA + CPVB for breast cancer surgery published before December 31, 2020. The Cochrane Handbook for Systematic Reviews of Intervention 5.0.2 was adopted for bias risk assessment, and Review Manager 5.3 software (RevMan, The Cochrane Collaboration, http://tech.cochrane.org/revman) was applied for meta-analysis of the literature.

Results: A total of 15 studies that satisfied the requirements were included, involving a total of 1,435 research subjects. The results of our meta-analysis showed the following: the visual analogue scale (VAS) score of the observation group (group A) was significantly reduced [mean difference (MD) =-0.68; 95% confidential interval (CI): -1.04 - -0.33; Z=3.80; P=0.0001]; the level of monocyte chemoattractant protein -1 (MCP-1) was notably decreased (MD =-18.64; 95% CI: -29.68 - -7.61; Z=3.31; P=0.0009); the level of tumor necrosis factor-α (TNF-α) was markedly lower (MD =-1.89; 95% CI: -2.66 - -1.13; Z=4.87; P<0.00001); the interleukin-6 (IL-6) level was obviously reduced (MD =-12.10; 95% CI: -19.22 - -4.99; Z=3.33; P=0.0009); and the incidence of postoperative adverse reactions was substantially decreased (MD = 0.16; 95% CI: 0.07-0.36; Z=4.47; P<0.00001). Compared with group B, the differences of the above five indicators showed statistical significance. In addition, the heart rate (HR) (MD =-1.56; 95% CI: -6.20 - 3.08; Z=0.66; P=0.51), mean arterial pressure (MAP) (MD = 4.66; 95% CI: -0.12 -9.43; Z=1.91; P=0.06), Ramsay score (MD =0.44; 95% CI: -0.06-0.93; Z=1.73; P=0.08) of patients in group A showed no statistical differences compared to group B.

Conclusions: GA + CPVB applied to breast cancer surgery for analgesia can reduce the levels of MCP-1, TNF-α, and IL-6 in patients, thereby providing good postoperative analgesia. Therefore, GA + CPVB could effectively reduce the incidence of pain and adverse reactions in patients, and is effective for analgesia in breast cancer surgery.

Keywords: General anesthesia combined with continuous paravertebral block (GA combined with CPVB); analgesia; breast cancer surgery; meta-analysis.