By: Buck Tilton

The name "trenchfoot" came from World War I, when the troops stood in cold, wet trenches for days without relief. It is sometimes, today, called "immersion foot," nerve and muscle damage that results from prolonged exposure to moisture and/or cold without ice formation (as in frostbite) in the cells of the affected area.

Trenchfoot is divided into three phases.
Phase one is the period of time when blood vessels are contricted by the cold and wetness inside the shoe or boot, and too little oxygen is carried to the cells of the foot. The foot is cold to the touch, slightly swollen, slightly discolored, numb, maybe a little tender to touch. When the foot is rewarmed, the damaged tissue usually looks red, and feels sensitive, and the discomfort may last from hours to days.

Phase two is the period when the cells of the foot have become damaged by the lack of adequate circulation. When the blood vessels open back up, the tissue swells with excess fluid. Patients complain of tingling pain that never lets up. A foot check will reveal swelling. On rewarming, blisters form, and, later, ulcers where the blisters have fallen off revealing dead tissue underneath. In severe cases, gangrene will result. Suffering may last from 2 to 6 weeks, and medications for pain are often prescribed.

Phase three may last weeks to months. The swelling subsides, and the foot takes on a normal appearance once again. During this phase, the patient may complain of increased perspiration in the foot, increased sensitivity to cold, and varying degrees of pain, itching, and paresthesia (a creeping, tingling, prickly feeling). The damaged foot may be more susceptible to cold injury in the future.

Here's what should be done if you think you, or a companion, is developing trenchfoot. Stop and carefully dry the cold foot or feet. If the foot looks dirty, carefully wash it before drying it. Keep it elevated above the level of the foot-owner's heart while you gently rewarm the foot with passive skin-to-skin contact. No rubbing or placing the foot near a strong heat source such as a fire or stove, both of which can damage the tissue of the cold foot. Start the patient on a regimen of over-the-counter anti-inflammatory drugs (aspirin or, even better, ibuprofen), following the directions on the label.

Remember it will probably take 24 to 48 hours before the severity of the damage is fully apparent. If you end up with a painful, obviously swollen foot that develops blisters, that patient needs the attention of a physician. Whether or not that patient can walk out to a physician will be determined by the patient. If they can do it, let them.

Trenchfoot is encouraged by poor nutrition, dehydration, wet socks, inadequate clothing, and the constriction of healthy blood flow in the feet by too-tight shoes and socks. People who sweat heavily are more susceptible, but everyone can prevent trenchfoot by paying attention to their feet. Keep a dry pair of socks on hand at all times, preferably packed in a plastic bag to make sure they stay dry. Make sure your boots fit with plenty of room for the socks you choose to wear. Don't add more socks if your feet get cold--get bigger boots, or boots with more insulation, or add insulation to the outside of your boots with gaiters.