Croup: Laryngotracheobronchitits (LTB) and Epiglottitis

What is Croup?
term used to describe the inspiratory barking sound associated with a partial upper airway obstruction
inspiratory stridor
subglottic airway obstruction (LTB)
epiglottitis: supraglottic airway obstruction
Where Does Croup/Epiglottitis Affect?
LTB can affect the lower laryngeal area, trachea, and occasionally the bronchi (subglottic)
epiglottitis is an inflammation of the supraglottic area; includes the epiglottis, aryepiglottic folds and false vocal cords
Laryngotracheobronchitis (LTB)
Parainfluenzae viruses cause most cases, with Type 1 being the most common and Type 3 the least common
Other Causes of LTB
influenzae A and B
herpes simplex virus
mycoplasma pneumoniae
bacterial infection caused by Haemophilus influenzae B
transmitted via aerosol droplets
onset usually abrupt
progresses rapidly over 2-4 hours
as supraglottic area becomes swollen breathing becomes noisy and tongue is thrust forward during inspiration; child may drool
inspiratory stridor is usually softer and lower in pitch
Clinical Data Seen in Croup/Epiglottitis
increased blood pressure
dim breath sounds
inspiratory stridor
use of accessory muscles on inspiration
substernal/intercostal retractions
mild to moderate: acute respiratory alkalosis
severe: acute respiratory acidosis
Chest X-Ray
LTB: narrowing of the upper airway (steeple sign; pencil point)
epiglottitis: haziness in supraglottic area (acute) thumb sign
General Management
temperature control, adequate hydration, humidification of inspired air
monitor vital signs, degree of retractions and mental status
early recognition may be life saving in epiglottitis
history of airway obstruction in the general exam
do not exam the mouth or the throat (if MD is present for an emergency trach)
inspection of larynx/pharynx is a big no-no in epiglottitis; only done in the OR
laternal neck to differentiate between LTB, epiglottitis or other obstruction