Prevention and Treatment of Nonfreezing Cold Injuries and Warm Water Immersion Tissue Injuries: Supplement to Wilderness Medical Society Clinical Practice Guidelines for the Prevention and Treatment of Frostbite.

We convened an expert panel to develop evidence-based guidelines for the evaluation, treatment, and prevention of nonfreezing cold injuries (NFCIs; trench foot and immersion foot) and warm water immersion injuries (warm water immersion foot and tropical immersion foot) in prehospital and hospital settings. The panel graded the recommendations based on the quality of supporting evidence and the balance between benefits and risks/burdens according to the criteria published by the American College of Chest Physicians. Treatment is more difficult with NFCIs than with warm water immersion injuries. In contrast to warm water immersion injuries that usually resolve without sequelae, NFCIs may cause prolonged debilitating symptoms, including neuropathic pain and cold sensitivity.

A review of trench foot: a disease of the past in the present.

From the French Invasion of Russia in 1812, to Glastonbury festival in 2007, trench foot has been reported, yet the exact nature of the condition remains unclear. This review explores the pathogenesis and treatment of trench foot. Trench foot is considered to be a nonfreezing cold injury often complicated by infection, in which exposure to cold temperatures just above freezing, combined with moisture, results in a peripheral vasoneuropathy. The presence of physical trauma, bacterial or fungal infections, malnutrition, venous hypertension and lymphoedema mean that some individuals are at greater risk of trench foot. Trench foot may be prevented by warming the feet, changing socks, staying active, rubbing the skin with oil and regularly inspecting the feet. Avoiding risk factors may help prevent the condition. The management of trench foot is less clear. Vasodilators such as iloprost and nicotinyl tartrate or sympathectomy may help. Trench foot may lead to necrosis, cellulitis, sepsis and amputation. It remains a poorly understood condition.

Preventing and treating trench foot: validation of an educational manual for military personnel.

OBJECTIVE:: To develop and validate an educational manual on the prevention and treatment of trench foot for military personnel. METHOD:: This is a prospective, descriptive, observational study. A manual was developed based on a literature review of books, theses and articles published in the last 10 years. The manual was evaluated by an expert committee of the Brazilian Army, and tested and validated by military students from an Army Sargent School in Brazil. Students evaluated the following parameters: definition of trench foot, risk of trench foot development among the military, risk factors, identification of trench foot, preventive measures, treatment of trench foot, and final considerations. RESULTS:: A total of 99 military students participated in the testing. Some parameters were exclusively evaluated by the experts, 12 physicians and 11 nurses, and rated as 'good or very good' as follows: thematic content (100%), graphic display (100%), topic sequence (100%), clarity of language and comprehension of information (91.3%) and illustrations (95.6%). Other parameters were rated as 'good or very good' by both the experts and military students, as follows: definition of trench foot (100% and 85.8%), risk of trench foot among the military (95.6% and 86.8%), risk factors (100% and 82.8%), identification of trench foot (100% and 86.8%), preventive measures (100% and 81.8%), treatment (95.6% and 84.8%) and final considerations (95.6% and 81.82 %), respectively. Cronbach's alpha was 0.891 for consistency and 0.854 for reliability. CONCLUSION:: The educational manual was validated by health professionals, tested by military students, and showed to be a consistent, reliable and valid educational instrument for the prevention and treatment of trench foot.

Trench foot: the medical response in the first World War 1914-18.

The approaching 90-year anniversary of United States entry into the Great War is an apt time to examine the response to trench foot (now called nonfreezing cold injury [NFCI]) in this conflict. Trench foot appeared in the winter of 1914, characterized by pedal swelling, numbness, and pain. It was quickly recognized by military-medical authorities. There was little debate over whether it was frostbite or new condition, and it was quickly accepted as a specific disease. The major etiologies proposed were exposure, diet, and infection. The opinion emerged that it was caused by circulatory changes in the foot caused by cold, wet, and pressure. Predisposing factors included dietary inadequacy and fatigue. A number of labels were first given to the disease. However, the name "trench foot" was eventually officially sanctioned. Trench foot became a serious problem for the Allies, leading to 75 000 casualties in the British and 2000 in the American forces. Therapy for trench foot involved a number of conventional, tried-and-tested, and conservative methods. Some more innovative techniques were used. Amputation was only used as a last resort. Prevention involved general measures to improve the trench environment; modification of the footwear worn by the men; and the provision of greases to protect them from moisture. The medical reaction to this condition seems to have been relatively effective. The causation was identified, and prophylactic measures were introduced to fit this model; these seem to have been successful in reducing the prevalence of the condition by 1917-18.

The immersion foot syndrome. 1946.

1. Prolonged exposure of the extremities to cold insufficient to cause tissue freezing produces a well-defined syndrome. 'Immersion foot' is one of the descriptive but inaccurate terms applied to this syndrome. The clinical features, aetiology, pathology, prevention, and treatment of immersion foot are considered in detail. A discussion on pathogenesis is also included. 2. In the natural history of a typical case of immersion foot there are four stages: the period of exposure and the pre-hyperaemic, hyperaemic, and post-hyperaemic stages. 3. During exposure and immediately after rescue the feet are cold, numb, swollen, and pulseless. Intense vasoconstriction sufficient to arrest blood-flow is believed to be the predominant factor during this phase. 4. This is followed by a period of intense hyperaemia, increased swelling, and severe pain. Hyperaemia is due to the release in chilled and ischaemic tissues of relatively stable vasodilator metabolites; pain may be the result of relative anoxia of sensory nerve-endings. 5. Within 7-10 days of rescue the intense hyperaemia and swelling subside and pain diminishes in intensity. A lesser degree of hyperaemia may persist for several weeks. Objective disturbances of sensation and sweating and muscular atrophy and paralysis now become apparent. These findings are correlated with damage to the peripheral nerves. 6. After several weeks the feet become cold-sensitive; when exposed to low temperature they cool abnormally and may remain cold for several hours. Hyperhidrosis frequently accompanies this cold-sensitivity. The factors responsible for these phenomena are incompletely understood; several possible explanations are considered. 7. Severe cases may develop blisters and gangrene. The latter is usually superficial and massive loss of tissue is rare. 8. The hands may be affected but seldom as severely as the feet. The essential features of immersion hand are the same as those of immersion foot. 9. Prognosis depends upon severity. The extent of anaesthesia at 7-10 days has been found a useful guide to the latter, and has formed a basis of a method of classification. 10. Rapid warming of chilled tissues is condemned. Cold therapy is of value for the relief of pain in the hyperaemic stage, but should not be used in the pre-hyperaemic stage. Sympathectomy and other measures designed to increase the peripheral circulation should not be employed immediately after rescue, but may have a place in the treatment of the later cold-sensitive state. This paper records the results of observations made during 1941 and 1942. Delay in publication has been necessary because of war-time difficulties of maintaining contact between authors. In this respect we have received much help from Surgeon Rear-Admiral J. W. McNee. We wish to thank Professors R. S. Aitken and J. R. Learmonth for much helpful advice during the preparation of the paper. The charts have been prepared by the technical staff of the Wilkie Surgical Research Laboratory, University of Edinburgh. During the period of the study, one of us (R. L. R.) was in receipt of a personal grant from the Medical Research Council.

Use of antioxidants for the prophylaxis of cold-induced peripheral nerve injury.

"Trench foot" is a particular risk for those involved in adventure tourism, for soldiers in winter mountain training exercises, and for the homeless. Nonfreezing cold nerve injury is characterized by axonal degeneration, which is attributed to free radicals released during cycles of ischemia and reperfusion. This pilot study sought to determine whether the administration of antioxidants might prevent or ameliorate the development of cold nerve injury. Twenty-six rats were divided into two groups. Group 1 animals received, by gavage, a mixture of vitamin C (150 mg/kg/d), vitamin E (100 mg/kg/d), and N-acetyl-L-cysteine (250 mg/kg/d) daily for 4 weeks. Allopurinol (20 mg/kg/d) was added in the last 4 days of treatment. Group 2 animals served as controls and did not receive any antioxidant supplements. After 1 month, two cycles of sciatic nerve cooling (0 degrees C) were induced in 10 controls and 10 experimental animals using circulating water through a nerve cuff. Six additional control animals were subjected to surgery but did not undergo nerve cooling. All animals were killed on the third postoperative day, and their nerves were processed for ultrastructural and quantitative studies. The proportion of degenerated myelinated and unmyelinated axons showed no significant difference between treated and untreated animals. We conclude that the administration of commonly used antioxidants does not prevent cold nerve injury.

Warm water immersion foot: still a threat to the soldier.

We report a significant incidence of warm water immersion foot (WWIF) in a light infantry battalion during a field exercise. Four hundred soldiers belonging to this battalion were surveyed to determine the prevalence of the WWIF syndrome. One hundred forty-nine soldiers surveyed developed the WWIF syndrome. The affected soldiers had a wide range of disability, ranging from mild discomfort to the inability to ambulate. All soldiers had full recovery within 2 weeks of the injuries. Although the syndrome is self-limited, the loss of these soldiers from combat critically impaired the battalion in its mission. We present this report as a reminder that effective preventive measures should be taken prior to field exercises and deployments.

Trench foot--a study in military-medical responsiveness in the Great War, 1914-1918.

Along the nearly 15,000 miles of trenches on the western front in the Great War of 1914-1918, a condition known as "trench foot" caused serious attrition among the fighting troops and resulted in swollen limbs, impaired sensory nerves, inflammation, and even loss of tissue through gangrene. Physicians, sanitarians, and military officers explored numerous theories regarding etiology and treatment before focusing on a combined regimen of common-sense hygiene and strict military discipline.