Stomas are artificial openings of a hollow organ (for example the bowel). The bowel or urinary system is artificially opened onto the surface of the abdomen, allowing faeces or urine to drain, bypassing the distal portions of the bowel or urinary tract. A specially adapted bag (stoma bag) is fitted around the stoma to collect the waste products and is emptied as required.

A colostomy is where the large intestine (colon) is brought onto the skin. Colostomies drain more solid stools, as much of the water is reabsorbed in the remaining large intestine. They can be flatter to the skin (compared with ileostomies which have a spout), as the solid contents are less irritating to the surrounding skin. They are typically located in the left iliac fossa (LIF).

An ileostomy is where the end portion of the small bowel (ileum) is brought onto the skin. Ileostomies drain more liquid stools, as the fluid content is normally reabsorbed later, in the large intestine. They have a spout, which allows them to drain directly into a tightly fitting stoma bag without the contents coming into contact with the surrounding skin. They are typically located in the right iliac fossa (RIF).

A gastrostomy involves creating an artificial connection between the stomach and the abdominal wall. This can be used for providing feeds directly into the stomach in patients that cannot meet their nutritional needs by mouth. Percutaneous endoscopic gastrostomy (PEG) refers to when the gastrostomy is fitted by an endoscopy procedure.

A urostomy involves creating an opening from the urinary system onto the skin. They have a spout and are typically located in the right iliac fossa (RIF).

All patients with stomas should have training on how to manage the stoma and have regular follow-up with a specialist stoma nurse.


End Colostomy / End Ileostomy

An end colostomy is created after the removal of a section of the bowel, where the end part of the proximal portion of the bowel is brought onto the skin. Faeces are able to drain out of the end colostomy into a stoma bag. The other open end of the remaining bowel (the distal part) is sutured and left in the abdomen. It may be reversed at a later date, where the two ends are sutured together creating an anastomosis.

End colostomies are permanent after resection of abdomino-perineal resection (APR) because the entire rectum and anus have been removed. These are usually located in the lower left abdomen.

End ileostomies are permanent after a panproctocolectomy (total colectomy with removal of the large bowel, rectum and anus), for example in the treatment of inflammatory bowel disease or familial adenomatous polyposis (FAP). An alternative to this is to create an ileo-anal anastomosis (J-pouch). This is where the ileum is folded back on itself and fashioned into a larger pouch that functions a bit like a rectum. This “J-pouch” is then attached to the anus and collects stools prior to the person passing a motion.


Loop Colostomy / Loop Ileostomy

A loop colostomy or loop ileostomy is a temporary stoma used to allow a distal portion of the bowel and anastomosis to heal after surgery. They may be called a “covering” or “defunctioning” loop colostomy or ileostomy, as they allow faeces to bypass the distal, healing portion of bowel until healed and ready to restart normal function. They are usually reversed around 6-8 weeks later. The bowel is partially opened and folded so that there are two openings on the skin side-by-side, attached in the middle. 

“Loop” refers to it being the two ends (proximal and distal) of a section of small bowel being brought out onto the skin. The proximal end (the productive side) is turned inside out to form a spout to protect the surrounding skin. This distal end is flatter. This allows you to distinguish between the proximal and distal portions of the bowel.



A urostomy is used to drain urine from the kidney, bypassing the ureters, bladder and urethra. This may be used after a cystectomy (removal of the bladder).

Forming a urostomy involves creating an ileal conduit. A section of the ileum (15 – 20cm) is removed and end-to-end anastomosis is created so that the bowel is continuous. The ends of the ureters are anastomosed to the separated section of the ileum. The end of the section is brought out onto the skin as a stoma and drains urine directly from the ureters into a urostomy bag.

Urostomy bags need to fit tightly around the urostomy to avoid urine coming in contact with the skin. Urine in contact with the skin will cause irritation and skin damage.



Stomas have a number of possible complications:

  • Psycho-social impact
  • Local skin irritation
  • Parastomal hernia
  • Loss of bowel length leading to high output, dehydration and malnutrition
  • Constipation (colostomies)
  • Stenosis
  • Obstruction
  • Retraction (sinking into the skin)
  • Prolapse (telescoping of bowel through hernia site)
  • Bleeding
  • Granulomas causing raised red lumps around the stoma


Last updated May 2021