A 22-year-old man is brought to the emergency room after a house fire. He has burns around his mouth and his voice is hoarse, but breathing is unlabored.
What most appropriate next step in management?
With direct thermal injury to the upper airway or smoke inhalation, rapid and severe airway edema is a potentially lethal threat. Anticipating the need for intubation and establishing an early airway is critical. Perioral burns and singed nasal hair are signs that the oral cavity and pharynx should be further evaluated for mucosal injury, but these physical findings alone do not indicate an upper airway injury. Signs of impending respiratory compromise may include a hoarse voice, wheezing, or stridor; subjective dyspnea is a particularly concerning symptom, and should trigger prompt elective endotracheal intubation. In patients with combined multiple trauma, especially oral trauma, nasotracheal intubation may be useful but should be avoided if oral intubation is safe and easy.
What percentage burn does a patient have who has suffered burns to one leg (circumferential), one arm (circumferential), and the anterior trunk
A general idea of the burn size can be made by using the rule of nines. Each upper extremity accounts for 9% of the total body surface area (TBSA), each lower extremity accounts for 18%, the anterior and posterior trunk each accounts for 18%, the head and neck account for 9%, and the perineum accounts for 1%. Although the rule of nines is reasonably accurate for adults, a number of more precise charts have been developed that are particularly helpful in assessing pediatric burns. Most emergency rooms have such a chart. A diagram of the burn can be drawn on the chart, and more precise calculations of the burn size made from the accompanying TBSA estimates given.
Children younger than 4 years have much larger heads and smaller thighs in proportion to total body size than do adults. In infants the head accounts for nearly 20% of the TBSA; a child's body proportions do not fully reach adult percentages until adolescence. Even when using precise diagrams, interobserver variation may vary by as much as ±20%. An observer's experience with burned patients, rather than educational level, appears to be the best predictor of the accuracy of burn size estimation. For smaller burns, an accurate assessment of size can be made by using the patient's palmar hand surface, including the digits, which amounts for approximately 1% of TBSA.
A 40-year-old woman is admitted to the burn unit after an industrial fire at a plastics manufacturing plant with burns to the face and arms. Her electrocardiogram (ECG) shows S-T elevation, and initial chemistry panel and arterial blood gas reveal an anion gap metabolic acidosis with normal arterial carboxyhemoglobin.
What is the most appropriate next step?
Hydrogen cyanide toxicity may also be a component of smoke inhalation injury. Afflicted patients may have a persistent lactic acidosis or S-T elevation on ECG. Cyanide inhibits cytochrome oxidase, which is required for oxidative phosphorylation. Treatment consists of sodium thiosulfate, hydroxocobalamin, and 100% oxygen. Sodium thiosulfate works by transforming cyanide into a nontoxic thiocyanate derivative, but it works slowly and is not effective for acute therapy. Hydroxocobalamin quickly complexes with cyanide and is excreted by the kidney, and is recommended for immediate therapy. In the majority of patients, the lactic acidosis will resolve with ventilation and sodium thiosulfate treatment becomes unnecessary.
Which of the following is a common sequelae of electrical injury?
Myoglobinuria frequently accompanies electrical burns, but the clinical significance appears to be trivial. Disruption of muscle cells releases cellular debris and myoglobin into the circulation to be filtered by the kidney. If this condition is untreated, the consequence can be irreversible renal failure. However, modern burn resuscitation protocols alone appear to be sufficient treatment for myoglobinuria.
Cardiac damage, such as myocardial contusion or infarction, may be present. More likely, the conduction system may be deranged. Household current at 110 V either does no damage or induces ventricular fibrillation. If there are no electrocardiographic rhythm abnormalities present upon initial emergency department evaluation, the likelihood that they will appear later is minuscule. Even with high-voltage injuries, a normal cardiac rhythm on admission generally means that subsequent dysrhythmia is unlikely. Studies confirm that commonly measured cardiac enzymes bear little correlation to cardiac dysfunction, and elevated enzymes may be from skeletal muscle damage. Mandatory ECG monitoring and cardiac enzyme analysis in an ICU setting for 24 hours following injury is unnecessary in patients with electrical burns, even those resulting from high-voltage current, in patients who have stable cardiac rhythms on admission.
The nervous system is exquisitely sensitive to electricity. The most devastating injury with frequent brain damage occurs when current passes through the head, but spinal cord damage is possible whenever current has passed from one side of the body to the other. Schwann cells are quite susceptible, and delayed transverse myelitis can occur days or weeks after injury. Conduction initially remains normal through existing myelin, but as myelin wears out, it is not replaced and conduction ceases. Anterior spinal artery syndrome from vascular dysregulation can also precipitate spinal cord dysfunction. Damage to peripheral nerves is common and may cause permanent functional impairment. Every patient with an electrical injury must have a thorough neurologic examination as part of the initial assessment. Persistent neurologic symptoms may lead to chronic pain syndromes, and posttraumatic stress disorders are apparently more common after electrical burns than thermal burns.
Cataracts are a well-recognized sequela of high-voltage electrical burns. They occur in 5 to 7% of patients, frequently are bilateral, occur even in the absence of contact points on the head, and typically manifest within 1 to 2 years of injury. Electrically injured patients should undergo a thorough ophthalmologic examination early during their acute care.
An 8-year-old boy is brought to the emergency room after accidentally touching a hot iron with his forearm. On examination, the burned area has weeping blisters and is very tender to the touch.
What is the burn depth?
Burn wounds are commonly classified as superficial (first degree), partial thickness (second degree), full thickness (third degree), and fourth degree burns, which affect underlying soft tissue. Partial thickness burns are classified as either superficial or deep partial thickness burns by depth of involved dermis. Clinically, first-degree burns are painful but do not blister, second- degree burns have dermal involvement and are extremely painful with weeping and blisters, and third-degree burns are leathery, painless, and nonblanching.