Final answer:
The practical nurse measures the stoma size when preparing a new ostomy bag to ensure that the appliance fits well to prevent leakage and skin irritation around the stoma. Accurate measurement and a proper fit are essential for patient comfort and to avoid potential complications.
Step-by-step explanation:
When preparing to apply a new ostomy bag for a client's colostomy, the practical nurse measures the stoma size to ensure a proper fit of the ostomy appliance. A snug and accurate fit is crucial for preventing leakage and protecting the skin around the stoma. If the stoma opening on the bag is too large, waste can come into contact with the skin causing irritation, and if it is too small, it could constrict the stoma, leading to discomfort and potential complications.
Before applying a new ostomy bag, it is important to take and update stoma measurements as the stoma may change in size and shape, particularly during the first few weeks following surgery. The skin surrounding the stoma should be kept clean and dry to promote healthy skin and effective adhesion of the ostomy appliance. The practical nurse may use specialized measuring guides or transparent stoma size gauges to measure the stoma accurately.