Which protrusion measurement indicates convexity use?

• A. <1 inch protrusion
• B. >1 inch protrusion
• C. No protrusion
• D. Exact 1 inch protrusion

Answer: (A)

Convexity is used when the stoma doesn’t protrude much from the abdomen, so the barrier can’t form a good seal on its own. If the stoma’s protrusion is less than about 1 inch, the skin around it may be flat or recessed, making leaks more likely with a flat barrier. A convex barrier applies gentle outward pressure around the stoma, helping to push the skin and stoma area outward enough to create a better seal and reduce leakage.

If the stoma protrudes more than 1 inch, a flat barrier usually seals well, and adding convexity can press on the stoma and surrounding skin, which isn’t desirable. So the measurement guiding convexity use is less than 1 inch of protrusion.