Colostomy & Ileostomy

The Concept

A stoma is a surgically created opening that brings a segment of bowel to the surface of the abdominal wall, allowing intestinal contents to be diverted into an external appliance. The two main intestinal stomas are the colostomy (an opening of the colon) and the ileostomy (an opening of the ileum), and being able to distinguish them clinically is a classic exam and ward skill.

Distinguishing Colostomy from Ileostomy

The spout of an ileostomy is deliberate: the small-bowel effluent is liquid and rich in digestive enzymes, so protruding the stoma protects the surrounding skin from corrosive contact, whereas the solid colonic output of a colostomy allows it to be flush.

Indications & Types

Stomas are formed to divert faeces (protecting a distal anastomosis — a defunctioning loop stoma), for decompression, or as a permanent outlet after removal of the distal bowel (e.g. An end colostomy after an abdominoperineal resection or Hartmann's procedure). An end stoma has one opening; a loop stoma has two (and is typically temporary).

Complications

Complications are commonly examined and include skin excoriation, retraction, prolapse, stenosis, parastomal hernia, ischaemia/necrosis, bleeding, and — particularly with a high-output ileostomy — dehydration and electrolyte loss. Good stoma-nurse support, correct siting and appliance care prevent many of these.

Siting & Quality of Life

Correct pre-operative siting of a stoma by a stoma nurse — away from the waistline, bony prominences, scars and skin creases, where the patient can see and reach it — is crucial to a well-functioning stoma and to quality of life. Poor siting leads to leakage, skin problems and appliance failure, which is why elective stomas are marked before surgery and patients receive dedicated stoma-care education.

The Bottom Line

The examinable essence is distinguishing a flush, LIF, solid-output colostomy from a spouted, RIF, liquid-output ileostomy, and knowing the indications and complications of each.

Reversal & Permanence

Whether a stoma is temporary or permanent is an important counselling point. A defunctioning loop stoma protecting a distal anastomosis is usually reversed after the anastomosis has healed, whereas an end colostomy after an abdominoperineal resection is permanent. Patients need clear information about which they have and, where relevant, the timing and risks of reversal surgery.

The ileostomy spout protects skin from digestive enzymes.

• Stoma = bowel opened onto the abdominal wall into an appliance; colostomy (colon) vs ileostomy (ileum).
• Colostomy: usually LIF, flush, solid output; ileostomy: usually RIF, spouted (protects skin), liquid output.
• Indications: defunction/protect an anastomosis, diversion, decompression, or permanent (end colostomy after APR/Hartmann's).
• End stoma (one opening) vs loop stoma (two, usually temporary).
• Complications: skin excoriation, retraction, prolapse, stenosis, parastomal hernia, ischaemia; high-output ileostomy → dehydration.