Situation: A 60-year-old man had an abdominoperineal resection with a permanent descending colostomy for rectal cancer 7 days ago. The stoma is pink and moist, and the colostomy is functioning. His wife will help him at home. The nurse begins discharge teaching. Two weeks after discharge, his wife reports that the skin around the stoma is red. The stoma now measures 30 mm across; at discharge it measured 34 mm, and she still cuts the skin barrier using the 36-mm template given at discharge. Which instruction should the nurse give?

A new stoma shrinks as postoperative swelling subsides, so it is re-measured about weekly for 6 to 8 weeks. The barrier opening should be only about 1.5 to 3 mm larger than the stoma; a 36-mm opening around a 30-mm stoma leaves a ring of skin exposed to stool, causing the redness. For a 30-mm stoma, an opening of about 32 mm is correct.

The redness around the stoma two weeks after discharge is a classic sign of irritant contact dermatitis from effluent leaking onto peristomal skin. The wife is still using the 36-mm template given at discharge, but the stoma has shrunk from 34 mm to 30 mm as postoperative edema resolved. This leaves a 6-mm ring of exposed skin around the stoma—well beyond the acceptable gap—allowing stool and digestive enzymes to contact and break down the skin.

A new stoma shrinks as postoperative swelling subsides, so it must be re-measured about weekly for the first 6 to 8 weeks. The barrier opening should be only 1.5 to 3 mm larger than the stoma itself. For a 30-mm stoma, the correct opening is approximately 32 mm. This snug fit protects the peristomal skin from effluent while avoiding pressure or cutting injury to the stoma tissue.

Opening size	Gap around stoma	Result
36 mm (current, from discharge template)	6 mm exposed skin	Effluent contacts skin, causing erythema and irritation
30 mm (exact stoma size)	0 mm	Risk of cutting or constricting the stoma as it moves or swells slightly
32 mm (correct)	2 mm (within 1.5–3 mm range)	Protects skin while allowing safe clearance

Watch out! Option 1 is unsafe because applying lotion under the barrier interferes with adhesion and does not solve the exposure problem. Option 2 is too tight—cutting exactly to 30 mm risks trauma to the stoma from friction or pressure. Option 4 would worsen the problem by exposing even more skin to effluent.

Peristomal skin irritation is one of the most common complications for ostomates, and the primary prevention is a correctly fitted pouching system. Clinical studies show that erythema can develop rapidly when skin barriers do not fit properly, and that patient and family education on measuring and cutting the barrier is essential to maintaining skin integrity. The wife should be taught to re-measure the stoma at its base with a measuring guide, cut the barrier to 32 mm, and reassess weekly as the stoma continues to stabilize over the first two months postoperatively.