Background: One prerequisite for the safe stapling of anastomoses is the formation of perfectly aligned B-shaped staples. Using an animal model, this study investigated whether precompression enhances secure staple formation.
Methods: A 45-mm linear stapler with a blue cartridge (staple leg length, 3.5 mm) was used on three portions each of six porcine stomachs (cardia, center, and pylorus). Staple shape and height were examined according to the precompression time (0, 1, or 5 min) before firing. The shape was classified as optimal or suboptimal, and the heights of the staples were measured individually. The completeness of the proximal staple lines also was compared with the distal lines.
Results: The optimal staple rate in the 5-min group (52.7%) was significantly higher than in the 1-min group (28.7%; p<0.001) or the 0-min group (17.1%; p=0.002). The optimal staple rate in the 5-min group for the cardiac portion (mean wall thickness, 2.7 mm) reached 98.9%. However, this rate was less than 50% in the center (5.3 mm) and pylorus (4.2 mm) portions regardless of the precompression time. Compared with the root side, the top side of the cartridge had a lower optimal rate (45.3 vs. 18.7%; p<0.001). A high correlation of completeness was observed between the distal and proximal sides of the stump.
Conclusions: When a linear stapling device is used, proper staple formation is correlated with intestinal wall thickness, and a sufficient amount of precompression time is effective for gaining the secure staple formation.