After debridement the underlying dermis will appear erythematous and wet, will be painful, and will blanch underpressure. Healing is dependent on the uninjured dermis andusually occurs within about 2 weeks without the need forskin grafting and without scarring. Deep partial-thickness(also second-degree) burns involve the entire epidermis anddeeper portions of the dermis. These burns may also haveblistering, but the dermal base is less blanching, mottled pinkor white, and less painful than superficial partial-thicknessburns. They behave more like full-thickness burns and willoften require excision and grafting. Full-thickness (third-degree and fourth-degree) burns involve all skin layers. Theyappear dry, white, dark red, brown, or black in color. Theydo not blanch and are usually insensate. Full-thickness burnsrequire surgical management. Fourth-degree burns involveunderlying fascia, muscle, or bone and may require reconstruction in addition to grafting. Inhalation injuries should be suspected if there are facial burns, singed nasal hairs, orcarbonaceous sputum. Hoarseness on vocalization also isconsistent with a supraglottic injury. Inhalation injuries mayresult in bronchospasm, airway inflammation, and impairedpulmonary function.
There are multiple methods and charts available for calculating the percentage of skin surface involved in a burn.One method that may be used for children of various agesis presented in Figure 44-1. The extent of skin involvement of older adolescent and adult patients may be estimated as follows: each upper extremity, 9%; each lower extremity, 18%;anterior trunk, 18%; posterior trunk, 18%; head, 9%; andperineum, 1%.
The location of the burn is important in assessing the risk of disability. The risk is greatest when the face, eyes, ears, feet, perineum, or hands are involved. Inhalation injuries not only cause respiratory compromise but also may result in difficulty in eating and drinking.
Initial laboratory testing, including complete blood count, type and crossmatch for blood, coagulation studies, basic chemistry profile, arterial blood gas, and chest radiograph, can be helpful for patients with major burns. A carboxyhemoglobin assessment should be performed for any suspected inhalation exposure (a house or closed-space fire or a burn victim who requires cardiopulmonary resuscitation). Cyanide levels should be considered in children who sustain smoke inhalation and have altered mental status. Unusual patterns of burns may increase suspicion of child abuse and result in appropriate evaluation to assess for nonaccidental trauma to the skeleton or central nervous system.
For severe burns, care is best managed by a multidisciplinary team in a qualified burn center. The American Burn Association criteria for patients who should be transferred to a burn center are: partial and full-thickness burns greater than 10% total body surface area (TBSA) in patients less than 10 years old or more than 50 years old, or greater than 20% TBSA in other age groups; partial and full-thickness burns involving the face, hands, feet, genitalia, perineum, or major joints; electrical burns; chemical burns; inhalation injury; burn injury in patients with preexisting medical conditions that could complicate management, prolong recovery, or increase mortality rate; any burn with concomitant trauma in which the burn injury poses the greatest risk; burn injury in children admitted to hospitals without qualified personnel or equipment for pediatric care; burn injury in patients requiring special social, emotional, or rehabilitative support, including child abuse cases.
Initial treatment should follow the ABCs of resuscitation. Airway management should include assessment for the presence of airway or inhalation injury, with early intubation if such an injury is suspected. Smoke inhalation may be associated with carbon monoxide toxicity; 100% humidified oxygen should be given if hypoxia or inhalation is suspected.