Emergency Medicine · Burn Management

Thermal Burns

USMLE2PANCE
7

Bets

The facts most likely to be tested

1

The Parkland formula dictates that lactated Ringer's solution is the fluid of choice for resuscitation, calculated as 4 mL × weight (kg) × % total body surface area (TBSA) burned over 24 hours.

Confidence:
2

Full-thickness (third-degree) burns are characterized by a leathery, white, or charred appearance and are notably painless due to the destruction of nerve endings.

Confidence:
3

Inhalation injury is suspected in patients with facial burns, singed nasal hairs, carbonaceous sputum, or hoarseness, necessitating immediate endotracheal intubation to secure the airway.

Confidence:
4

The Rule of Nines is used to estimate TBSA, assigning 9% to the head and each arm, and 18% to the anterior trunk, posterior trunk, and each leg.

Confidence:
5

Circumferential full-thickness burns to the chest or extremities require an urgent escharotomy to prevent compartment syndrome and respiratory compromise.

Confidence:
6

Silver sulfadiazine is the standard topical antimicrobial for burn wounds, but it is contraindicated in patients with sulfa allergies or burns involving the face.

Confidence:
7

Carbon monoxide poisoning must be ruled out in enclosed-space fire victims by measuring carboxyhemoglobin levels via arterial blood gas (ABG), as pulse oximetry remains falsely normal.

Confidence:

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A 34-year-old male is brought to the emergency department after being pulled from a house fire. On physical exam, he has singed nasal hairs, sooty oropharynx, and hoarseness when speaking. He has circumferential, leathery, painless burns covering his entire chest and both upper extremities. His oxygen saturation is 99% on room air, but he appears confused and agitated.

What is the most appropriate next step in management?

+Reveal answer

Endotracheal intubation

The patient exhibits classic signs of inhalation injury (singed hairs, hoarseness, soot), which mandates immediate airway protection to prevent obstruction from laryngeal edema, as tested by the third bet.

Mo

Depth

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High yield triage

Etiology / Epidemiology

Most common in pediatrics and elderly due to accidental contact with hot liquids or surfaces.

Clinical Manifestations

Full-thickness burns are painless and leathery; eschar formation is the hallmark.

Diagnosis

Rule of Nines is the gold standard for initial TBSA estimation in adults.

Treatment

Lactated Ringer's is the fluid of choice; avoid cold water immersion to prevent hypothermia.

Prognosis

Inhalation injury is the leading cause of mortality; monitor for airway compromise.

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Epidemiology & Etiology

Thermal burns result from contact with fire, steam, or hot liquids. Pediatric patients are at highest risk for scalds, while occupational exposure remains a primary cause in adults. Always screen for non-accidental trauma in children with symmetric or patterned burns.

Pertinent Anatomy

The skin is divided into the epidermis, dermis, and subcutaneous tissue. Depth of injury determines the need for grafting. The zone of stasis is the area of potentially salvageable tissue surrounding the necrotic core.

Pathophysiology

Thermal injury triggers a massive systemic inflammatory response leading to capillary leak and third-spacing. This results in hypovolemic shock if not aggressively resuscitated. The Parkland formula guides initial fluid resuscitation to maintain organ perfusion.

Clinical Manifestations

Superficial burns are painful and erythematous. Partial-thickness burns present with blisters and blanching. Full-thickness burns are painless, dry, and leathery. Hoarseness, carbonaceous sputum, and singed nasal hairs are red flags for inhalation injury.

Diagnosis

Use the Rule of Nines to estimate Total Body Surface Area (TBSA). A Lund-Browder chart is more accurate for pediatric patients. ABGs and carboxyhemoglobin levels are mandatory if inhalation injury is suspected.

Treatment

Initiate Lactated Ringer's using the Parkland formula (4mL x kg x %TBSA) over 24 hours, with half given in the first 8 hours. Do not use prophylactic systemic antibiotics as they increase resistance. Apply Silver sulfadiazine for topical antimicrobial coverage, but avoid on the face due to staining.

Prognosis

Major complications include sepsis, contractures, and hypermetabolic state. Patients with >20% TBSA require formal burn center admission. Monitor for compartment syndrome in circumferential limb burns, which may require an emergent escharotomy.

Differential Diagnosis

Chemical burn: requires immediate irrigation

Electrical burn: high risk of cardiac arrhythmias

Stevens-Johnson Syndrome: involves mucosal surfaces and systemic symptoms

Staphylococcal Scalded Skin Syndrome: spares mucous membranes

Necrotizing fasciitis: rapid progression with crepitus