Abdominal stomas

The word “stoma” is derived from the Greek for mouth and describes an artificial opening in the abdominal wall, fashioned by a surgeon to divert the flow of faeces or urine. An estimated 100 000 people in the United Kingdom have a stoma, and about 65% of these stomas are permanent.1 Medical students are often asked to examine patients with abdominal stomas during bedside surgical teaching and in final bachelor of medicine examinations. Here we attempt to demystify the construction and function of these often life saving procedures.

The most common stomas are colostomy (end or loop), ileostomy (end, loop, or end-loop), double barrel, and urostomy (ileal conduit). Stomas that involve bowel are created principally if no physical, distal bowel is present (for example, surgical resection of rectum and anus); if no normally functioning, distal bowel is present (for example, incontinence); if the distal bowel needs to be defunctioned or rested (for example, distal fistula in Crohn's disease, distal surgical anastomosis, and inoperable rectal cancer); or if a primary anastomosis would be unsafe to perform (for example, in acute diverticulitis with peritontitis).