Injuries to skin and adjacent deeper tissues often require the expertise of surgeons, usually with specific training in plastic surgery, trauma, or burn care. However, hospitalists are often involved in the initial evaluation, stabilization, and management of these children when they present to the hospital or require admission. Three major types of injuries are the focus of this chapter: thermal and chemical burns, electrical injuries, and intravenous infiltrates.^1-3

Burns cause significant morbidity and mortality in the pediatric population throughout the world.⁴ For children under 14, unintentional burns are among the top 10 causes of death due to unintentional injury, and burns are among the top 10 causes of non-fatal injuries for children under 4 treated in emergency departments.⁵ Burns are most common among infants and toddlers, with scald injuries predominating in this age group.⁶ Approximately 78% of these burns are accidental injuries caused by the child, 20% are accidental injuries caused by another person, and 2% to 3% are acts of abuse.⁷ Burns due to thermal causes (flame, contact, scald, or steam) require similar but distinct management from chemical or electrical burns. Careful attention must be paid to both the acute and chronic phases of burn care, because many injuries require long-term rehabilitation and an interdisciplinary approach to minimize their functional, cosmetic, and emotional impact.

PATHOPHYSIOLOGY

Following a thermal injury, the body responds locally and systemically. Locally, there are three zones of injury. The zone of coagulation necrosis is an eschar, with irreversible surface tissue injury from the direct heat insult. The zone of stasis is an area of reversible, salvageable cell injury due to a microvascular reaction in the dermis associated with vasoconstriction and thrombosis. Cell damage is not complete, but inflammatory mediators and injured microcirculation put viable tissue at risk. Beyond this is the zone of hyperemia, which lacks direct cell injury but exhibits vasodilation secondary to the surrounding inflammatory cascade. Full recovery in this zone is expected in the absence of additional insults. Systemically, the loss of an effective skin barrier leads to fluid losses, decreased resistance to infection, and the release of vasoactive mediators, affecting hemodynamic status and creating a hypermetabolic state.

Bacterial colonization of burned tissue can cause focal and systemic infection. Vulnerability to infection ensues not only because of disruption of the protective epidermal layer but also because burns are relatively ischemic; thus defensive elements of the innate immune system as well as systemic antibiotics are unable to penetrate burned tissue.

CLINICAL PRESENTATION

The diagnosis of a thermal injury is usually evident from the history and is obvious on presentation, although the relevant history may be lacking owing to caregiver absence or subterfuge. Thermal injuries are typically divided into first-, second-, third- and fourth-degree burns (Figure 162-1).

First-degree burns are superficial burns involving only the epidermis. They are associated with erythema, mild edema, dryness, and pain; no blistering is seen. Pain typically resolves in 2 to 3 days, and wounds heal in 3 to 6 days. Sunburns are common first-degree burns.

Second-degree burns are partial-thickness burns extending into the dermis, often caused by hot liquids. Superficial second-degree burns involve the epidermis and superficial dermis. Blisters are typically present; the wounds are erythematous, edematous, moist, and extremely painful due to exposed nerve endings. These burns heal in 2 to 3 weeks because the dermal appendages that regenerate epithelial cells are preserved. Deep second-degree burns penetrate deep into the dermal layer. Blisters with weeping exudates are usually present; the wounds are dark red or yellow-white, with a slightly moist surface. These burns are less painful because fewer viable nerve endings are present. They generally require more than 3 weeks to heal and are at risk for hypertrophic scar formation.

Third-degree burns penetrate through the dermis into the subcutaneous fat. They are insensate because cutaneous nerves are destroyed, although there is pain in the surrounding second-degree burns. They appear dry, leathery, and charred and are pearly white or parchment-like; superficial vessel thrombosis may be visible. These burns are often caused by flame or grease. Resurfacing and grafting are required for closure. Deep second- and third-degree burns may be difficult to distinguish clinically, and the presence of multiple burn types limits the utility of pain as a delineator.

Fourth-degree burns extend to underlying muscle or bone.

DIFFERENTIAL DIAGNOSIS

As with any injury in a child, vigilance for signs of abuse or neglect is essential. These include an inconsistent mechanism of injury, variation in historical details, delayed presentation, or a classic intentional injury pattern. A classic intentional scald injury pattern is buttock injury accompanied by perineal and foot injury that spares the flexion creases, suggestive of defensive posturing. Other intentional injury patterns include scald burns in a stocking or glove distribution and deep local contact burns, such as from a cigarette.

Certain skin conditions such as Stevens-Johnson syndrome or toxic epidermal necrolysis and staphylococcal scalded skin syndrome may mimic a diffuse burn injury but should be readily distinguished by the history and overall clinical picture.

DIAGNOSTIC EVALUATION AND MANAGEMENT

Initial Stabilization

As with any seriously injured patient, the first management priorities are airway, breathing, and circulation. Careful airway assessment is critical in burn victims because progressive airway involvement may develop. The risk of inhalation injury, with associated airway edema and compromise, is high in victims of an indoor or chemical fire or a hot liquid ingestion. Clinical clues to airway injury include facial burns, hoarseness, stridor, oral lesions, carbonaceous sputum or deposits in the nares, singed eyebrows or facial hair, and shortness of breath. In the case of airway injury, early intubation is preferred because of the likelihood of evolving edema. Intubation may also be required in patients with burns covering a large body surface area because of the associated systemic effects, including pulmonary edema. Consider the possibility of carbon monoxide poisoning, especially in a patient with impaired thinking, syncope, or coma that is otherwise unexplained, or if there is a strong exposure history (e.g. kerosene or gas stove, automobile exhaust). Pertinent historical information should be elicited from emergency personnel, including length of exposure, extrication time, and any concern for conflicting stories regarding the injury. Supportive management may include early placement of multiple intravenous lines, which can be inserted through burned tissue if no other sites are available, laboratory evaluation, an arterial line, a Foley catheter, and a nasogastric tube.

Initial burn management includes removal of clothing and jewelry to avoid ischemia secondary to swelling and heat conduction. For large burned areas, a clean sheet may be placed to reduce contamination and pain during the initial stabilization. Cold water can be applied to small burn injuries to prevent the spread of heat and decrease pain. Do not use ice, which can cause direct skin injury. Application of cooling measures to large burns should be avoided because of the risk of hypothermia. Treatment rooms should be kept warm to reduce heat loss, especially for small children.

After airway, breathing, and circulation have been stabilized, identification of the burn type and total surface area involved is imperative for appropriate management and disposition. For burn surface area assessment, the “rule of 9s” is typically used in adults and children older than 15 years: each arm represents 9% of the body surface area; the head and neck combined are 9%; 18% each is allocated to the anterior torso, posterior torso, and each leg; and the perineum represents 1%. In younger children, however, this is inaccurate because they have relatively larger heads and a different body size distribution. A pediatric variation allocates 18% for the head and neck, 15% for each lower extremity, 10% for each upper extremity, and 16% each for the anterior and posterior torso. For a rapid estimation, a child’s hand (palm plus digits) represents approximately 1% of the body surface area. For more precise estimates, charts that estimate burn area based on age can be used (Figure 162-2). First-degree burns are not included in surface area calculations for purposes of fluid resuscitation.

Determine whether any vulnerable areas are involved, specifically the face, hands, feet, genitalia, perineum, and major joints, and evaluate for corneal injury in patients with facial burns. Be vigilant for circumferential burns that may compromise circulation or respiration. In such cases, early escharotomy may be indicated. Chest wall escharotomy incisions are made along the anterior axillary lines, along the costal margins, and across the top of the chest. Extremity incisions should cross the joints because they are particularly vulnerable to constriction owing to the lack of subcutaneous tissue. Consider measuring compartment pressures to assess for compartment syndrome. Pressures in excess of 25 mmHg suggest the need for escharotomy or compartment decompression. Elevated pressures sufficient to cause muscle necrosis can exist in the presence of palpable pulses.

Patients with burns involving large body surface areas have extensive fluid requirements, and early and aggressive fluid resuscitation is critical. In the first 24 hours, there are large fluid shifts owing to third-spacing of intravascular volume into injured tissue and injury-related histamine release. There is some controversy regarding the use of crystalloid versus colloid, but most providers begin with the former. There are many formulas for calculating these fluid requirements. The Parkland formula calculates estimated fluid requirements in the first 24 hours:

The first half of the total fluid replacement is given over the first 8 hours, and the second half is given over the next 16 hours.

Most clinicians add maintenance fluids for children younger than 5 years.⁸ The goal is a urine output of at least 1 mL/kg per hour; placement of a transurethral bladder (Foley) catheter provides more accurate and continuous measurements.

It is important to complete secondary survey for nonburn-related injuries, particularly if the history involves trauma.

Pain control should be initiated promptly, typically with intravenous narcotics. Tetanus status should be assessed and addressed, and tetanus immunoglobulin should be considered in patients with incomplete or unknown immunization status and large contaminated wounds.

Ongoing Care

After early stabilization and initial management, continuing needs are addressed. Burn patients experience a hyperdynamic state with increased metabolic demands. Calorie requirements are based on burn surface area. Enteral feedings are generally delayed for the first 72 hours owing to gastroparesis and ileus, which are common in severely burned patients.