Immersion foot

Immersion foot, also known as trench foot, is a non-freezing cold injury resulting from prolonged exposure of the feet to cold and wet conditions. It causes damage to nerves and blood vessels, leading to symptoms such as numbness, pain, swelling, blistering, and tissue maceration. This condition is distinct from frostbite, as it occurs at temperatures above freezing.

This code is appropriate for documenting diagnoses of immersion foot where the patient's feet have been exposed to cold, wet, and unsanitary conditions for an extended period. Documentation should clearly indicate the environmental factors contributing to the injury and differentiate it from other cold-related injuries. It is commonly seen in military personnel, homeless individuals, or those exposed to prolonged outdoor activities without adequate foot protection.

• Differentiate from frostbite (991.0-991.3) which involves tissue freezing.
• Consider an external cause code (E-code) to describe the circumstances of the injury, if applicable.
• Document the specific affected anatomical site (e.g., left foot, right foot, bilateral) for comprehensive record-keeping.