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Utskriftsdato (27.4.2017)

Stoma


Medical editor Birgit Sunde
Stoma Nurse
Oslo University Hospital

General

Intestinal stoma is often required during treatment of rectal cancer and sometimes for colon cancer. The stoma is either permanent or temporary. Stoma is also constructed for temporary relief of distal anastomosis or ileus.

Permanent stoma is prepared when the rectum is removed or when there is an inoperable tumor or ileus due to extreme adherences. Preferably, it is placed as close to the anus as possible to provide the best possible reabsorption of nutrition and fluid.

The procedure may be performed by laparoscopy.

A stoma can have with one or two openings. The type of stoma depends on the purpose of the stoma and anatomical conditions in the abdomen.

End stoma 

The colon is divided and the oral end is brought out. The end stoma is easier to handle and is better looking than a loop stoma. The end stoma is usually performed for permanent stomas and for relief of fistulas.

Loop stoma 

The colon is not divided but is pulled out like a loop through the abdominal wall. An opening is made in the top of the loop. The stoma has two openings: one oral and one aboral. The stoma can be prepared in two ways:

  • symmetrical—an opening is made on the top of the extracted "backwards U." The ingoing and outgoing openings of the bowel looks similar. Symmetric loop stoma are usually performed for colostomy  .
  • asymmetrical—the oral part of the bowel is brought forward and empties easier into the bag while the aboral part of the bowel is at the skin level and the opening is small. Asymmetric loop stoma is usually created for an ileostomy .

Sigmoid colostomy 

Sigmoid colostomy is the most common form of colostomy. The stoma is installed if it is not technically possible or sensible to anastomose the colon to the rectum/anal canal. It is then constructed as a permanent end stoma. This is done in 15-30% of patients with rectal cancer.

Indications

Permanent:

  • for rectal amputation
  • to avoid permanent incontinence of poor anal sphincter function (Hartmann's operation)
  • to relieve an inoperable fistula anally from the stoma

Temporary:

  • for preoperative radiation
  • relief of rectal ileus

Sigmoid colostomies are easy to maintain. The stools usually has a normal consistency and causes little irritation to the skin.

Transverse colostomy 

The transverse colon is brought out in the right rectus muscle. This is a loop stoma and is often temporary. It is often difficult to maintain because the stoma is voluminous and the feces is thin and foul-smelling. This type of stoma is associated with more complications than a sigmoidostomy. As a temporary stoma it has similar frequency of complications as ileostomas.

There is a risk that the bowel content may pass into the distal opening with an incomplete relief of stools.

Indications

  • relieve stenosis in the left colon
  • relieve low anastomosis or rectum resection
  • allow rinsing of the left colon through the stoma in limited anastomosis leakage

Ileostomy

The ileum is brought out  20-30 cm from the cecum and preferably in the right rectus muscle as an asymmetrical loop stoma. It is relatively simple to construct but can be difficult to maintain due to thin fecal content. The longer nipple will help avoiding damage to the skin.

Indications

  • protect anastomoses after rectosigmoid resection
  • relieve bowel obstruction
  • relieve preoperative radiation of stenosis due to colorectal cancer
  • relieve fistula

Indications for stomas

  • Cancer in the rectum (rectum amputation, Hartmann)
  • Cancer in the colon

Goals

  • Facilitate output of bowel contents
  • Relieve the bowel/stenosis/fistula

Equipment

  • Laparotomy tray and possibly laparoscopy equipment.
  • A device to place under the loop.

Preparation

The patient should be prepared for:
  • anatomical and physiological changes following the operation
  • what a stoma involves
  • stoma equipment and how it functions
  • the stoma is edematous the first weeks after the operation and that it will normalize

Stoma marking

The patient is informed of the purpose of the stoma marking. The goal is to find appropriate placement in order for the patient to maintain the stoma.

It is important to see the patient, lying, sitting, standing, and during movement. By seeing the abdomen in different positions, the abdomen's shape is emphasized such that individual considerations are taken during marking. The patient should be able to address their own wishes and desires.

Factors influencing the location

  • the stoma should be visible to the patient.
  • the stoma should be placed within the rectus muscle
  • the stoma disc and stoma should not come in conflict with skin folds, groin, hollow areas, iliac crest, scars, hernias, the navel, or straps for prosthesis or binder
  • the stoma should not hamper the clothing
  • choice of stoma type

Marking:

  • The rectus muscle is identified on the side where the stoma will be placed
  • The appropriate stoma location is adjusted by using a piece of tape which is moved about on the abdomen when the patient lies down, sits, and stands.
  • The patient must be offered to walk with the disc and bag to check that the stoma marking is optimal.
  • Final marking for placement is done with a waterproof marker.

Implementation

  • When the stoma is not brought out through the abdominal inscision but through a separate hole in the abdominal wall it will be easier to handle. For transversostomy: an incision is made in the right rectus muscle and the omentum is dissected off the attachment to the relevant part of the colon. It may be difficult to obtain sufficient length of the bowel without damaging the vessel supply if the abdominal wall is thick. For an ileostomy, this is more simple.
  • The least amount of skin is removed if the stoma is not brought out through the abdominal inscision.
  • The bowel is pulled out as a backwards "U" and is not divided.
  • The bowel is sutured to the peritoneum.
  • The bowel is sutured to the anterior fascia.
  • A tube or skin bridge is placed under the loop at the skin level to prevent the bowel from retracting.
  • The bowel lumen is opened at the top and the bowel wall is everted and sutured to the skin.
  • For a section in the right rectus chain, the stoma is placed out through a separate incision to facilitate stoma hygiene.
  • Colostomy should preferably be pulled 1-2 cm out over the skin level. Ileostomy: 2-3 cm.

End sigmoid colostomy:

  • A mid-line incision to the right of the navel is made.
  • The bowel is divided with a closing-dividing stapler.
  • The bowel is mobilized by adequate division of the vessels without damaging the vessel archade to permit the bowel to be pulled out through the skin without tightening.
  • In the abdominal wall, the peritoneum and posterior fascia leaf are split.
  • The musculature is split length-wise and as much as necessary transversally.
  • The anterior fascia leaf is split in a cross.
  • A skin cylinder with underlying fatty tissue is removed up to the fascia.
  • The extracted bowel opening is sutured to the fascia and everted with sutures  in the bowel tube, mucosa  and skin.

Follow-up

The very first stoma changes after an operation should be performed on the third postoperative day. If the stoma bandage leaks, this must be changed earlier. The change should be carried out by a stoma nurse/nurse while the patient is in the supine position. The stoma is observed for possible infection, necrotizing mucosa or abdominal wall, loosening of sutures, and for leakage of air and bowel content. Bag inflation is a signs of bowel activity. It is appropriate to use a colorless, drainable bag in the first period since the bowel content is thinner in the beginning. If a bag with a filter is used, the filter should be covered.

As soon as the patient is ready for it, the patient is trained for stoma changing/cleaning. Training should occur daily until the patient has mastered it.

Transverse colostomies and ileostomies can be closed after about six weeks. For closing of ileostomy, there is a higher chance of postoperative ileus and possibly also for bowel leakage than with colostomy.

For Hartmann's operation, the goal in some instances is to perform a re-anastomosis of the bowels and to avoid permanent stoma.

Complications of stoma

Early

  • Infection in the subcutaneous tissues occurs relatively often and more commonly with obesity.
  • Necrotizing of mucosa or the entire abdominal wall occurs more frequently in patients with a thick subcutaneous fat layer.
  • Loosening of eversion sutures along the edge occurs relatively frequently.
  • Retraction of stoma to the skin level or under occurs relatively rarely, but more frequently for loop colostomy. Retraction can cause overflow to the disconnected bowel. This is especially unfortunate in fistula relief.
  • Colo-cutaneous/ileo-cutaneous fistulas occur rarely.

Delayed

  • Peristomal hernia is a complication where the stoma bulges out like lump on the skin. This can make attachment of the stoma bag more difficult and the stoma may have to be moved.
  • Stenosis in the stoma opening occurs relatively rarely. It occurs if the bowel opening is not adequately inverted or if the tip of the stoma necrotizes down to or under the skin level.
  • Retraction of the stoma down to or under the skin level occurs relatively rarely.
  • Prolapse of stoma is a relatively rare complication where the bowel turns itself 10 cm or more out through the stoma opening. This happens most often in transverse colostomy stomas. The herniation can cause increased pressure to the bowel vessels through the abdominal wall and possible cause bowel necrosis. This complication can be treated conservatively but may relapse.