LARYNGOTRACHEOBRONCHITIS Prepared by: Emmylou R. Mari

Triggered mostly by viral infection of the upper airway Affects the lower laryngeal area, trachea, and occasionally the bronchi (laryngotracheobronchitis or LTB) Edema and swelling of the mucous membrane causing the reduction in cross- sectional area of airway

Viral agents are more commonly implicated The parainfluenza virus type 1, 2 and 3 are the most common etiologies Other viruses associated are influenza A and B, adenovirus, respiratory synctial virus and Measles

Mycoplasma pneumoniae; Corynebacterium diptheriae; Staphylococcus aeureus; Streptococcus pneumoniae; Hemophilus influenzae; and Moraxella catarrhalis.

The infection causes inflammation of the larynx, trachea, bronchi, bronchioles, and lung parenchyma. Obstruction caused by swelling and inflammatory exudates develops and becomes pronounced in the subglottic region. Obstruction increases the work of breathing; rarely, tiring results in hypercapnia. Atelectasis may occur concurrently if the bronchioles become obstructed.

Vital Signs: Increase Respiratory Rate (Tachypnea), Heart Rate (Pulse), Blood Pressure and Temperature Diminished Breath Sounds Use of Accessory Muscles During Inspiration Substernal and Intercostal Retraction Cyanosis Inspiratory Stridor: upper airway for infants is relatively small Barking: outu.be outu.be

A frontal X-ray of the neck – it may show a characteristic narrowing of the trachea, called the “steeple sign”, because of the subglottic stenosis, which is similar to a steeple in shape (inverted V-shape).

Supportive care including intravenous fluids to maintain hydration and oxygen inhalation to relieve hypoxia A single dose of dexamethasone 0.6 mg/kg may decrease the severity and duration of illness Inhalation of epinephrine may decrease symptoms of stridor and respiratory distress immediately Antibiotics are not usually indicated

Extension of infectious process to other regions of the respiratory tract, e.g. middle ear or pulmonary parenchyma Bacterial tracheitis: a bacterial infection of the trachea and is capable of producing airway obstruction. One of the most common causes is Staphylococcus aureus and often follows a recent viral upper respiratory infection.

Many cases of croup have been prevented by immunization for influenza and diptheria Viral croup is usually self-limited disease, but can rarely result in death from respiratory failure. Symptoms usually improve within 2 days, but may last for up to 7 days.

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