Cutaneous Cold Weather Injuries in the US Military
Service members of the US Military are at risk for cutaneous cold weather injuries due to the demands of military training, combat operations, and peacekeeping missions. In this article, we review common cutaneous cold weather injuries likely to be encountered in the military, including frostbite, immersion foot, pernio, Raynaud phenomenon (RP), and cold urticaria. We aim to bring awareness to these specific injuries to improve diagnostic and treatment outcomes, both in service members and civilians.
Practice Points
- Military service members are at an increased risk for cutaneous cold weather injuries in certain circumstances due to the demands of military training and combat operations.
- Cold weather may cause injury by directly damaging tissues, leading to neurovascular disruption, and by exacerbating existing medical conditions.
Raynaud Phenomenon
Raynaud phenomenon (also known as Raynaud’s) is characterized by cold-induced extremity triphasic color changes—initial blanching and pallor that transitions to cyanosis and finally erythema with associated pain during the recovery stage. The fingers are the most commonly involved appendages and can have a symmetric distribution, but RP also has been observed on the feet, lips, nose, and ears. In severe cases, it can cause ulceration.25 The prevalence of RP may be as high as 5% in the general population.26 It more commonly is primary or idiopathic with no underlying cause or secondary with an associated underlying systemic disease.
Cold-induced vasoconstriction is a normal physiologic response, but in RP, the response becomes a vasospasm and is pathological. Autoimmune and connective tissue diseases often are associated with secondary RP. Other risk factors include female sex, smoking, family history in a first-degree relative, and certain medications.25 A study in northern Sweden also identified a history of frostbite as a risk factor for the development of RP.27 This condition can notably restrict mobility and deployability of affected service members as well as the types of manual tasks that they may be required to perform. As such, this condition can be disqualifying for military service.11
Many patients improve with conservative treatment consisting of cold avoidance, smoking cessation, and avoidance of medications that worsen the vasospasm; however, some patients develop pain and chronic disease, which can become so severe and ischemic that digital loss is threatened.25 When needed, calcium channel blockers commonly are used for treatment and can be used prophylactically to reduce flare rates and severity of disease. If this class of medications is ineffective or is not tolerated, there are other medications and treatments to consider, which are beyond the scope of this article.25
Cold Urticaria
Cold urticaria is a subset of physical urticaria in which symptoms occur in response to a cutaneous cold stimulus. It can be primary or secondary, with potential underlying causes including cryoglobulinemia, infections, and some medications. Systemic involvement is possible with extensive cold contact and can include severe anaphylaxis. This condition is diagnosed using a cold stimulation test. Cold exposure avoidance and second-generation antihistamines are considered first-line treatment. Because anaphylaxis is possible, patients should be given an epinephrine pen and should be instructed to avoid swimming in cold water.28 Cold urticaria is disqualifying for military service.11
A 2013 case report described a 29-year-old woman on active duty in the US Air Force whose presenting symptoms included urticaria on the exposed skin on the arms when doing physical training in the rain.29 In this case, secondary causes were eliminated, and she was diagnosed with primary acquired cold urticaria. This patient was eventually medically discharged from the air force because management with antihistamines failed, and her symptoms limited her ability to function in even mildly cold environments.29
Final Thoughts
An understanding of cold weather injuries and other dermatologic conditions that may be flared by cold exposure is important for a medically ready military force, as there are implications for accession, training, and combat operations. Although the focus of this article has been on the military, these conditions also are seen in civilian medicine in patient populations routinely exposed to cold weather. This becomes especially pertinent in high-risk patients such as extreme athletes, homeless individuals, or those who have other predisposing characteristics such as chronic alcohol use. Appropriate cold weather gear, training, and deliberate mission or activity planning are important interventions in preventing cutaneous cold weather injuries within the military.
