Certified Wound Ostomy Nurse (CWON) Practice Test

Which of the following describes a blister?

1. Fluid-filled lesion less than 0.5cm

2. Fluid-filled lesion greater than 0.5cm

3. Scab formed by dried exudate

4. Nonviable tissue

The correct answer is: Fluid-filled lesion less than 0.5cm

The description of a blister is correctly associated with a fluid-filled lesion that measures less than 0.5 centimeters. Blisters are typically characterized by their small size and the presence of clear fluid beneath the outer layer of skin, known as the epidermis. This accumulation of fluid is a response to injury or irritation, allowing the skin to heal by protecting underlying tissues. The distinction in size is crucial because medical terminology differentiates between blisters and larger lesions; a greater size corresponds to other terms, such as bullae, which are fluid-filled lesions greater than 0.5 centimeters. Understanding these precise definitions is essential for accurately assessing skin conditions and communicating in clinical settings.