HISTORY. The child usually has a history of an upper respiratory infection and a runny nose (rhinorrhea). After 12 to 48 hours of respiratory symptoms, such as cough and increased respiratory rate, the child develops a barking, seal-like cough; a hoarse cry; and inspiratory stridor. The symptoms tend to occur in the late evening and improve during the day, which may be due to the lower cortisol levels at night. The initial sign of LTB is increasing respiratory distress. The child may develop flaring of the nares, a prolonged expiratory phase, and use of accessory muscles. When you auscultate the child's lungs, the breath sounds may be diminished and you may hear inspiratory stridor. The child may have a mild fever. Increasing respiratory obstruction is indicated by any of the following: increasing stridor, suprasternal and intercostal retractions, respiratory rate above 60, tachycardia, cyanosis, pallor, and restlessness. Assessment is done by the Westley scale, which evaluates the severity of symptoms based on five factors: (1) stridor, (2) retractions, (3) air entry, (4) cyanosis, and (5) level of consciousness. In addition, each type of croup can have particular symptoms, as shown in Table 1.

The course of the infection lasts several days to several weeks, although 60% resolve within 48 hours. Some children may have a lingering, barking cough. A child may have LTB more than once but will outgrow it as the size of the airway increases.

PHYSICAL EXAM.

Forms of Laryngotracheobronchitis

FORMS OF CROUP	SYMPTOMS
LTB	Fever, breathing problems at night, inability to breathe out because of bronchial edema, decreased breath sounds, expiratory rhonchi, scattered crackles
Laryngitis	Mild respiratory distress in children, increased respiratory distress in infants; sore throat and cough, inspiratory stridor, dyspnea; late phases: severe dyspnea, fatigue, exhaustion
Acute spasmodic laryngitis	Hoarseness, rhinorrhea, cough, noisy inspiratory phase that worsens at night, anxiety, labored breathing, cyanosis, rapid pulse; the most severe symptoms may occur on the first night, with lessening symptoms on each of the following nights

PSYCHOSOCIAL. The parents and child will be apprehensive. Assess the parents' ability to cope with the emergency situation, and intervene as appropriate. Note that many children are treated at home rather than in the hospital; your teaching plan may need to consider home rather than hospital management.

Diagnostic Highlights

General Comments: Most children require no diagnostic testing and can be diagnosed by the history and physical. If diagnostic testing is needed, it involves identifying the causative organism, determining oxygenation status, and ruling out masses as a cause of obstruction.

Test	Normal Result	Abnormality with Condition	Explanation
Blood culture; throat culture	No growth; no organism identified	Causative organism identified	Distinguishes between bacterial and viral infections
Pulse oximetry	B 95%	< 95%	Low oxygen saturation is present if there is obstruction in the lung passages
X-rays	Normal structure	Narrowing of the upper airway and edema in epiglottal and laryngeal areas	Narrowing and/or blocked airway is characteristic of LTB