North Carolina EMT State Practice Exam

What is the common name for immersion foot, resulting from prolonged exposure to cold water?

1. Trench foot

2. Frostbite

3. Chilblains

4. Cold urticaria

The correct answer is: Trench foot

Immersion foot is commonly known as trench foot. This condition occurs when the feet are submerged in cold water for extended periods, typically in temperatures above freezing but low enough to cause discomfort and physical harm. The skin and underlying tissues become damaged due to the prolonged exposure, which impairs circulation and can lead to serious complications if not treated properly. Trench foot is characterized by symptoms such as numbness, swelling, and possible blisters. While this condition is closely linked to historical contexts like World War I, where soldiers would experience it while in the trenches, it remains relevant in understanding the impact of cold water exposure. In contrast, frostbite is a more severe injury that occurs when skin and underlying tissues freeze due to extreme cold, chilblains refer to painful inflammation of small blood vessels in response to sudden warming from cold, and cold urticaria is an allergic reaction to cold that can cause hives. Each of these conditions involves cold exposure but differs significantly in mechanism and symptoms, highlighting why trench foot is the correct identification for immersion foot.