Creation of an artificial anus

Indications for surgery and selection of localization

The Maydl procedure can be performed on any part of the large intestine; however, in clinical practice, the sigmoid colon is most frequently used.

The creation of an artificial anus is indicated for severe lesions of the distal bowel when it is necessary to completely exclude them from the fecal passage. The main indications include:

• Rectal wounds.
• Unresectable tumors.
• Cicatricial strictures of the rectum.

The most important feature of Anus praeternaturalis is that it never closes spontaneously. Re-operation is required to restore the natural passage.

Surgical access and bowel mobilization

Surgical access is performed in the left iliac region. The incision is made obliquely: it runs parallel to the inguinal ligament and is located two fingerbreadths above it.

Dissection of the anterior abdominal wall tissues is performed strictly layer by layer:

1. The skin and the aponeurosis of the external oblique abdominal muscle are incised.
2. The internal oblique and transversus abdominis muscles are not transected—they are bluntly separated along the direction of the muscle fibers.
3. The peritoneum is incised between two forceps.

After opening the abdominal cavity, a loop of the sigmoid colon is withdrawn into the wound. An opening is formed in its mesentery, through which a gauze tape holder is passed (its ends are fixed with a clamp). The parietal peritoneum is sutured to the skin of the incision edges with interrupted silk sutures.

Creation of the "spur" — a key step

The creation of the "spur" is the most critical stage of the operation. The afferent and efferent loops of the exteriorized bowel are sutured together. For this purpose, a series of interrupted silk seromuscular sutures are placed over a length of 4–5 cm.

As a result of this suturing, the intestine acquires a sharp bend and externally resembles a double-barreled shotgun. It is this bend that forms the "spur," which prevents feces from entering the efferent limb.

After the "spur" is formed, the gauze tape holder is removed. The bowel itself is sutured to the parietal peritoneum with interrupted seromuscular sutures.

Opening of the intestinal lumen

The lumen of the intestine during the creation of an artificial anus is not opened immediately on the operating table. The exteriorized loop is left intact for 2–3 days.

After this time, the intestine is opened in the transverse direction. As a result, two isolated openings are formed:

• Proximal opening — serves for the outward diversion of fecal masses.
• Distal opening — leads to the excluded segment of the intestine. It is used for administering medications to the tumor or for draining breakdown products.

Completion of the anastomosis on the large intestine

If an anastomosis is required during surgery on the large intestine, surgeons adhere to a strict sequence for forming the intestinal suture:

• Posterior edge of the anastomosis: formed by an inverting suture.
• Anterior edge of the anastomosis: also sutured with an inverting suture.
• Second row: interrupted silk seromuscular sutures are placed.
• Third row: also consists of seromuscular interrupted sutures.
• Opening in the mesentery: must be closed with interrupted sutures.

Briefly: answers to topical questions

Class and exam questions

What else to study on this topic

• Technique of placing the inverting intestinal suture
• Interrupted seromuscular sutures: placement rules
• Topographic anatomy of the left iliac region
• Surgical approaches to the large intestine
• Closure of defects in the intestinal mesentery

Other topics in the "Abdominal Surgery" section

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