The majority of burn patients are treated and released from the ED. Of those hospitalized, more than 60% are admitted to 1 of the country's 125 burn centers. The risk of death from a major burn is associated with larger burn size, advanced age, concomitant inhalation injury, and female sex.
Burns are categorized by their size and depth. Burn size is calculated as the percentage of body surface area (BSA) involved. The most common method to estimate this is the rule of 9s (Fig. 125-1). A more accurate tool, especially in infants and children, is the Lund and Browder burn diagram (Fig. 125-2). For smaller burns, the patient's hand can be used to estimate the percentage of BSA, as the area of the back of the patient's hand represents approximately 1% of BSA.
Rule of 9s to estimate the percentage of burn.
Lund and Browder diagram to estimate the percentage of a burn.
Burn depth historically has been described in degrees: first, second, third, and fourth. A more clinically relevant classification scheme categorizes burns as superficial partial thickness, deep partial thickness, and full thickness. Table 125-1 summarizes the characteristics of each type of burn.
Table 125-1 Burn Depth Features Classified by Degree of Burn |Favorite Table|Download (.pdf)
Table 125-1 Burn Depth Features Classified by Degree of Burn
No blisters, painful
Superficial second-degree or superficial partial thickness
Epidermis and superficial dermis
Blisters, very painful
Hot water scald
14 to 21 days, no scar
Deep second-degree or deep partial thickness
Epidermis and deep dermis, sweat glands, and hair follicles
Blisters, very painful
Hot liquid, steam, grease, flame
3 to 8 weeks, permanent scar
Entire epidermis and dermis charred, pale, leathery; no pain
Months, severe scarring, skin grafts necessary
Entire epidermis and dermis, as well as bone, fat, and/or muscle
Months, multiple surgeries usually required
Inhalation injury occurs most frequently in closed-space fires and in patients with decreased cognition (intoxication, overdose, head injury). Both the upper and lower airway can be injured by heat, particulate matter, and toxic gases. Thermal injury is usually limited to the upper airway, and can result in acute airway compromise. Particulate matter can reach the terminal bronchioles and lead to bronchospasm and edema. Clinical indicators of inhalation injury include facial burns, singed nasal hair, soot in the upper airway, hoarseness, carbonaceous sputum, and wheezing. Carbon monoxide poisoning should be suspected in all patients with inhalation injuries. Hydrogen cyanide poisoning should be considered in fires involving nitrogen-containing polymer products such as wool, silk, polyurethane, and vinyl.