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A stoma is an opening (Greek for “mouth”) of a hollow viscus draining to
the skin which is created deliberately by the surgeon in order to serve a
purpose.
Depending on the organ involved, this could be a colostomy, ileostomy,
jejunostomy, gasrtostomy, ureterostomy etc.
In this chapter we will examine the commonest stomas which concern colorectal
surgery: colostomy and ileostomy.
A colostomy is the exteriorisation of a part of the colon. It could be sigmoid
colostomy, transverse colostomy or caecostomy.
An ileostomy is exteriorisation of the last part of the terminal ileum.
A jejunostomy is usually performed for feeding purposes – with artificial “enteral
nutrition”.
A stoma can be an “end” –stoma, if there is only one opening or a “loop” stoma
if there are two openings and through the stoma we can see both the proximal
and the distal lumens of the bowel.
Purpose of stomas
A stoma serves one of the following purposes:
a) Diverts the contents of the bowel to the exterior if there is bowel obstruction or
destruction of the distal part of the bowel.
b) If the anus has to be resected because of cancer (abdomino-perineal
resection of the rectum) or ulcerative colitis etc.
c) A temporary “defunctioning” stoma is often done to divert temporarily the
bowel contents from passing through an anastomosis which is at risk of leak. So
for example if an anterior resection of the rectum is too low and the field has
been irradiated there is a considerable risk of anastomotic leak. In this cases the
creation of a temporary defunctioning ileostomy or colostomy ensures that even
if the healing of the anastomosis tales a long time and there is leak, this will be
without consequences. At a later stage, 3-6 months later, the stoma can be
closed. A temporary stoma has often to be created in cases of intestinal
obstruction because joining up the bowel in those circumstances can result in
anastomotic leak.
d) In rare cases a colostomy is used to treat very severe constipation.
e) A colostomy is sometimes required to divert the faecal stream from inflamed
or infected areas. This is in cases of complex perianal fistulas or Crohn’s
disease etc.
Colostomy or ileostomy?
Both are used and the main factor for choice is anatomical, i.e. the location –
level of the bowel problem which we want to correct with the stoma. However in
some cases we have a choice. For example, when we do an anterior resection of
the rectum for cancer, it is possible to protect our anastomosis either with a
colostomy or witrh an ileostomy.
The factors taken into account have to do with both the nature of the stoma and
the ease and safety of closing it. The advantages of colostomy are that it
produces a small volume of semi-solid material which is easy to manage with a
single bag a day. On the other hand the material is more smelly and surgical
closure of the colostomy requires a major operation and is in itself subject to
anastomotic leak.
An ileostomy produces a large amount of fluid which smells less ( is not faeces)
but is sometimes more difficult to manage because of the volume and the skin
irritation. The skin irritation may be caused by the small bowel enzymes and can
be very bothersome for the patient. A very large amount of fluid may sometimes
be produced and lead to dehydration and electrolyte loss which may be
dangerous. Having said that, there technical ways and medication which ensure
that most ileostomies are free of problems. The main advantage of the ileostomy
is that it can be closed with a less major operation and it carries less risk of
complications on closure. Because of this the majority of colorectal surgeons
prefer a temporary ileostomy when performing an anterior resection of the
rectum.
Complications of stomas
Parastomal hernia (prolapse)
- It is corrected with surgery (usually with prosthetic mesh or re-location of
the stoma).
- It needs re-fashioning of the stoma
- It needs refashioning of the stoma
- Drainage required
- Usually controlled with large doses of loperamide and codeine. Six weeks
after creation ileostomy output usually reduces (“adapts”).
- Caused by adhesions and sometimes requires surgery
- Technical “tricks” on construction of the ileostomy such a “spout” , reduce
the risk. Skin excoriation is managed with creams and pastes and also
with precise fitting of individually tailored stoma bags which prevent leak.
A stoma can initially be a psychological shock for the patient. However all studies
show that not only this shock is very temporary and patients overcome it, but
also that Quality of Life with a stoma is as good as without. The only factor
that may be affected is the body image, but this varies from person to person
and psychological support and counselling can greatly help.
An indication of the degree of adaptation to life with a stoma is that almost one
third of patients with a temporary colostomy choose to keep it rather than
undergo further surgery.
Most unpleasant effects of the stoma result from complications which can be
treated either surgically or by an experienced stoma therapist. Stoma therapist
nurses are central in the management of stoma patients in the UK. The stoma
therapist always sees the patient before creation of the stoma in order to plan
the best location on the abdominal wall. The shape of each body is different, so
is the kind of clothes we wear according to gender, culture and fashion. The
stoma should be located in such a position that it does not interfere with the
body creases, the belt, the clothes and feels comfortable for the patient
regardless of whether they stand, sit or lie down.
Special opaque bags with filters prevent visualisation of the contents and
neutralise the odours. With the technique of colonic irrigation the patient can be
trained to empty the colon in the toilet once a day and then spend the rest of the
day wearing a patch with the colour of the skin instead of a bag. Experience
shows that people adapt so well that they can work normally whether as taxi
drivers, manual workers or fashion models. With appropriate training the stoma
does not prevent sports or even swimming. Sexual life is perfectly normal and
any problems have to do with altered body image which can usually be helped
with counselling.
A number of support groups for patients with stomas exist in the UK and
internationally, these provide very valuable education in the initial phases of life
with a stoma.
STOMAS: COLOSTOMY AND ILEOSTOMY