Are intersecting staple lines a hazard in intestinal anastomosis?

To determine the safety of intersecting staple lines, 22 pigs were operated upon with a functional end-to-end enteroanastomosis 40 cm distal to the ligament of Treitz using linear stapling devices. The procedure was repeated on the colon, where a colocolostomy was created. The blood flow at intersecting staple lines and single-row staple lines for each anastomosis was studied with the reference organ method 24 hours after the first operation. The purpose was to evaluate whether there is a reduction in blood flow at the site of intersecting staple lines, causing an increased risk for anastomotic leakage. The reduction in mean blood flow in crossing compared with noncrossing staple lines was 6 percent (-5-17 percent) for small bowel anastomoses and 7 percent (-6-19 percent) for colonic anastomoses. An equivalence test showed that, if a reduction in blood flow exists between crossing and noncrossing staple lines, it is most likely less than 30 percent (P less than 0.001) for both small bowel and colonic anastomoses. This experimental study demonstrates that intersecting staple lines in small bowel and colonic anastomoses do not reduce anastomotic blood flow to a dangerous level.