Circular staplers and anastomotic leakage in colorectal surgery: meta-analysis

Background Anastomotic leakage is a feared complication after colorectal resection. Recent advancements in surgical techniques, particularly the use of circular staplers, have aimed to improve postoperative outcomes. However, the optimal choice of circular stapler remains uncertain, with debate surrounding its impact on anastomotic leakage rates. The aim of this meta-analysis was to evaluate the impact of different circular stapler characteristics on anastomotic leakage occurrence after left colorectal resection. Methods A systematic review and meta-analysis using PubMed, Scopus, and Web of Science databases to identify studies on the correlation between circular staplers and anastomotic leakage occurrence were performed up to November 2023 (PROSPERO registration: CRD42024519036). The literature search was conducted according to the PRISMA guidelines and performed using the following search terms: 'colorectal surgery', 'staplers', 'complications'. Only retrospective, cohort, prospective and randomized clinical trials on anastomotic leakage rate after left colorectal resection, including adult patients (over 18 years of age) and published in English were included. Exclusion criteria were articles with different designs, and studies including extra-colonic or right/transverse colon diseases. The quality assessment of the study was performed using the Newcastle-Ottawa classification. The outcome of interest was the analysis of each staplers' characteristics including: diameter, number of rows, technology (manual versus powered) and anastomotic technique (single- versus double-stapling technique) on anastomotic leakage occurrence. Results Twenty-one retrospective studies were selected including 24 511 patients. A higher anastomotic leakage rate was documented for 31/33 mm stapler diameters compared with the 28/29 mm (OR -0.92, 95% c.i. -1.74 to -0.10; P = 0.02), while no significant difference was found between the 25 mm and 28/29 mm diameters (OR -0.46, 95% c.i. -1.39 to 0.46; P = 0.2). Similar anastomotic leakage rates were found for the two- and three-row circular stapler groups (OR -0.01, 95% c.i. -0.16 to 0.13; P = 0.85). Conversely, the powered technology related to a significantly lower rate of anastomotic leakage compared with the manual technology (OR -0.83, 95% c.i. -1.13 to -0.35; P < 0.001). Similarly, the single-stapling technique related to a lower rate of anastomotic leakage compared with the double-stapling technique (OR 0.79, 95% c.i. 0.33 to 1.25; P < 0.001). Conclusion This study shows a higher anastomotic leakage rate for larger circular staplers and manual technology. Similarly, the single-stapling technique has advantages over the double-stapling technique, while the tri-staple technology does not appear to confer advantages on anastomotic leakage occurrence.