Varnado's case example serves as a valuable reminder; WOC nurses are not immune to managing skin-related issues that are not common in their own practice regions, because Americans are more mobile than ever. Varnado's patient left the warm weather of Louisiana and brought back frostbite injury from the cold North. Minnesotans travel south for the winter and sometimes return with conditions less known in the north, such as recluse spider bite.
Frostbite is freezing of tissue most often on extremities that leads to tissue destruction.1-3 In general, frostbite causes morbidity but rarely causes mortality. However, when combined with hypothermia or wound-related sepsis, death is possible. Long-term effects of frostbite have been reported to range from cold sensitivity, joint stiffness, and cracking skin to tremors, osteoporosis, muscle atrophy, and amputation.4
The pathophysiology of frostbite injury on the cellular level is complex. Many of the characteristics of frostbite are similar to ischemia-reperfusion injury. Initially, cold tissue is damaged through vascular impairment and cellular injury. As rewarming occurs, cell swelling, erythrocyte and platelet aggregation, endothelial cell damage, thrombosis, tissue edema, increased compartment space pressure, bleb formation, localized ischemia, and tissue death may also occur. Tissue injury is greatest when cooling is slow, cold exposure is prolonged, rate of rewarming is slow, and especially when tissue partially thaws and refreezes.5-7
Many severe frostbite cases ultimately end up in burn units. As with thermal burns, frostbite injuries may be classified by degree of injury (Table 1).1,8
The epidemiology of frostbite in the United States is not known. A study involving 1,275 patients admitted to hospitals in Finland showed an incidence of 2.5 cases per 100,000 inhabitants.9 Frostbite affects people of all ages6,10: the adult athlete who runs outside no matter the temperature, the child who is reluctant to leave his or her winter fun to go inside and warm up, or as with Varnado's case study the 22-year-old college student. It is interesting to note that all 3 cases presented involved alcohol use, and in 2 cases there was a reluctance to see treatment due to lack of insurance.
The literature reports that frostbite patients tend to be male.6,11 However, a cross-sectional study involving 2,143 medical records or soldiers demonstrated that African American men and women were 4 times and 2.2 times (respectively) more likely to sustain cold weather injuries than white soldiers.11 Not surprisingly, the homeless are frequent victims of frostbite.7,12-14 One burn unit reported that 29% of homeless patients are admitted to burn units because of frostbite.12 Other predisposing factors and populations at risk include (1) persons who are stranded in the cold7,12-14; (2) cold weather rescuers, soldiers, and people who work in the cold2,3,10,11,14,15; (3) winter and high-altitude athletes,2,13,16,17 persons with altered mental status caused by trauma, alcohol, drug abuse, psychiatric illness6,12,18; (4) cigarette smokers or persons using vasoconstrictive drugs1,2; (5) individuals with inadequate or constrictive clothing12; and (6) those with underlying conditions such as malnutrition, infection, peripheral vascular disease, atherosclerosis, arthritis, diabetes mellitus, thyroid disease, or previous cold injury rendering them susceptible to cold related injury.2,13
Similar to burns, treatment for frostbite may take place in a variety of locations. The phases or level of care required for frostbite depends on the severity of the injury. Initial care generally takes place at the location that the injury occurs and addresses life-threatening conditions first. Wet clothing needs to be replaced with dry, soft clothing to minimize further heat loss. The affected area should not be rubbed with warm hands due to risk for further injury. Alcohol or sedatives should not be given as they may enhance heat loss. Rewarming of the affected area should be initiated as soon as possible, unless there is a danger of refreezing.4,7,19 If refreezing is a risk, clinicians are advised to transport the person to shelter rather than attempting to rewarm at the scene. The affected body part should be wrapped in a blanket for protection during transport.
Initial care may occur in an emergency department setting where potentially life-threatening conditions can be rapidly managed. Rapid rewarming of the affected body part is attempted using water or wet packs heated to 40[degrees]C to 42[degrees]C with a mild antibacterial soap. Warmer temperatures or dry heat should be avoided due to risk for thermal injury. Thawing usually requires 20 to 40 minutes and is complete when the distal tip of the affected area flushes.19 Patients with associated dislocations are reduced as soon as thawing is complete. Fractures are managed conservatively until postthaw edema has resolved. The only indication for early surgical intervention is debridement of necrotic tissue and fasciotomy in the case of compartment syndrome. Hemorrhagic blisters are left intact to reduce risk of infection to the injured extremity. Once thawed, the injury is kept in sterile sterile nonadherent dressings, elevated, and splinted when possible.13
Weeks may pass before frostbitten tissue demarcates to reveal viable and nonviable tissue.5 Therefore, amputation is rarely needed or delayed as long as possible. Lower extremity involvement, infection, and delay in seeking medical attention are associated with an increased risk of operative therapy. Surgical consultation will help guide long-term management, including debridement for infections not responding to conservative management or for skin grafting.6 Hyperbaric oxygen therapy may play a role in management of frostbite injury. However, literature on this topic is limited to case reports.5,20
The goals of management for frostbite include salvaging as much tissue as possible, achieving maximal return of function, optimizing nutrition for healing, and preventing complications. A number of pharmacologic interventions are presented in the literature to manage pain and to prevent complications such as microthrombosis, tetanus, and infection. The role of pain management is critical throughout the phases of recovery and especially before, during, and after rewarming to manage reperfusion pain.
Varnado discusses the importance of patient education in the prevention and management of frostbite injuries. Patient education may include consuming a high-protein, high-calorie diet to promote healing, smoking cessation, infection prevention, moisture control, and prevention of maceration between frostbitten digits, regaining range of motion of the affected body part. Patients should be counseled regarding their increased sensitivity to cold associated with burning and tingling with a strong emphasis on their susceptibility to frostbite and need to avoid cold. As with so many skin safety topics, the primary defense against frostbite is prevention by preplanning, hydrating, and using appropriate clothing particularly on hands and feet.15-17 Varnado's case examples remind us of the need to assess features of development that are pertinent to helping patients adapt these important preventive interventions.21
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