Three anastomosis configurations are widely accepted when joining lumens in the gastrointestinal tract:
- End-to-end anastomosis is indicated when both lumens have a similar, sufficiently large diameter and the likelihood of an anastomotic stenosis is minimal.
- End-to-side anastomosis is preferred when the luminal diameters differ.
- In ends with small lumens a side-to-side anastomosis produces an anastomosis with a large lumen and thus prevents later anastomotic stenosis.
Retrospective studies did not demonstrate any benefit for interrupted vs. a continuous suture technique in single-layer sutures. Benefits of the continuous technique include the smaller amount of foreign body material introduced, cost-effectiveness of the procedure, shorter duration of surgery, and uniform adjustment of suture tension along the entire circumference of the anastomosis. This reduces spillage of contaminated material into the surrounding tissue and abscess formation Drawbacks of continuous sutures: If the suture breaks, this will increase the risk of a complete dehiscence, and placing the stitches is less evident.
The continuous suture technique is suitable only for sections of intestine that can be rotated.
Edge-to-edge anastomoses benefit from earlier and increased vascularization.
During the exudative phase, the wound edges will undergo tissue edema. When tying the sutures and pulling on the suture material, keep the tendency of edema in mind. If the sutures are tied too tightly and the suture material is pulled too hard, this will result in secondary ischemia. Anastomoses which are too loose are not leak-proof.
Absorbable sutures are reasonable because they prevent chronic foreign body reaction and thus do not induce anastomotic stenosis.
Regarding the suturing technique, adequate distance both from the wound edge and adjacent sutures should be maintained.
Coating the sutures with doxycycline may increase suture strength.
Requirements for the suture material: Low tissue trauma, high flexibility, slippage with high knot security, good tissue compatibility, no bulging, no capillarity (wicking effect), high tensile strength with small suture size, specified absorption time, cost-effectiveness. There is no optimal suture that meets the specified requirements.
For anastomoses in the gastrointestinal tract, absorbable monofilament 4/0 or 3/0 sutures are used; alternatively, for interrupted sutures, braided (coated) absorbable sutures may also be used.
The most important layer when suturing the four-layered intestinal wall is the submucosa. The submucosa contains the most collagen fibers and is the layer where the vessels course. Sutures that do not include this important tissue layer only serve to appose and have no significant tensile strength.
In extramucosal sutures, the excess mucosa is compressed together edge-to-edge and the intestinal walls become slightly inverted.