A 28-month-old boy is brought to the emergency department late in the evening due to noisy… — USMLE Step 2 CK

A $28$ -month-old boy is brought to the emergency department late in the evening due to noisy breathing that began abruptly. His parents report that he had a mild subjective fever and nasal congestion for the past $3$ days. Earlier tonight, he awoke from sleep with a harsh, barking cough and severe respiratory distress. His temperature is $38.2^\circ\text{C}$ ( $100.8^\circ\text{F}$ ), pulse is $140/\text{min}$ , respirations are $42/\text{min}$ , and pulse oximetry is $95\%$ on room air. The patient is sitting upright on his mother's lap and appears highly anxious. Physical examination reveals high-pitched inspiratory sounds audible without a stethoscope, along with pronounced suprasternal and intercostal retractions. Auscultation of the lungs demonstrates referred upper airway noise but no focal wheezes or crackles. The oropharynx is clear without excessive drooling. Which of the following is the most appropriate next step in management?

Administration of aerosolized racemic epinephrine and oral dexamethasoneAnswer
B
Administration of aerosolized albuterol and oral prednisolone
C
Administration of intravenous ceftriaxone and vancomycin
D
Administration of oral azithromycin and observation
E
Administration of nebulized hypertonic saline and chest physiotherapy

Answer

The most appropriate next step is the administration of aerosolized racemic epinephrine and oral dexamethasone to rapidly decrease subglottic edema and prevent rebound inflammation.

The correct approach involves administering aerosolized racemic epinephrine and oral dexamethasone. This patient presents with moderate to severe croup, defined by the presence of inspiratory stridor at rest and marked retractions. Croup is a viral infection (usually parainfluenza) that causes swelling of the subglottic airway. Racemic epinephrine acts rapidly via alpha-adrenergic stimulation to cause mucosal vasoconstriction, decreasing subglottic edema and quickly relieving the upper airway obstruction. Because the effects of epinephrine are transient (lasting roughly

2

hours), systemic corticosteroids (like dexamethasone) are administered simultaneously to provide a sustained anti-inflammatory effect and prevent rebound edema.

Step-by-Step Solution

Identify the clinical syndrome from the patient's history and physical examination.

The patient has a viral prodrome, a barking cough, and inspiratory stridor, which is diagnostic of viral croup (laryngotracheobronchitis).

Recognizing the characteristic presentation distinguishes croup from lower airway diseases like asthma or bronchiolitis.

Assess the severity of the respiratory distress.

The patient has stridor at rest accompanied by suprasternal and intercostal retractions, indicating moderate to severe disease.

Severity dictates management; mild croup (stridor only with agitation) can be managed with steroids alone, whereas moderate to severe croup requires immediate airway stabilization.

Determine the optimal pharmacologic intervention based on disease severity.

Aerosolized racemic epinephrine is selected for rapid vasoconstriction and mucosal shrinkage, while oral dexamethasone is given for its longer-acting anti-inflammatory properties.

This combination addresses both the immediate life-threatening airway narrowing and the underlying inflammatory process.

Key Concept

Moderate to severe viral croup (indicated by stridor at rest and retractions) requires treatment with both aerosolized racemic epinephrine for rapid symptom relief and systemic corticosteroids to reduce ongoing subglottic inflammation.

Question

Answer

Step-by-Step Solution

Key Concept

Common Mistakes

Topics

More questions from this topic