1. Speaker : Dr. Wu Meng-Shu
CROUP
Speaker : Dr. Wu Meng-Shu

2. INTRODUCTION
Croup is a respiratory illness characterized by inspiratory stridor, cough, and hoarseness.
Inflammation in the larynx and subglottic airway.
A barking cough is the hallmark of croup among infants and young children.
Hoarseness predominates in older children and adults.
Usually mild and self-limited.
Significant upper airway obstruction, respiratory distress and, rarely, death, can occur.

3. Definition Laryngitis - hoarseness.
Laryngotracheitis (croup) - lower airway signs are absent, the typical barking cough will be present.
Laryngotracheobronchitis (LTB) - resulting in lower airway signs and sometimes more severe and bacterial superinfection.
Bacterial tracheitis (also called bacterial croup) - resulting in a thick, purulent exudate, which causes symptoms of upper airway obstruction.
Spasmodic croup - sudden onset of inspiratory stridor at night, short duration (several hours), and sudden cessation.

4. ETIOLOGY
Parainfluenza virus type 1 - the most common, especially the fall and winter epidemics .
RSV and adenoviruses
Measles
Influenza virus
Rhinoviruses, enteroviruses
Mycoplasma pneumoniae
The most common secondary bacterial pathogens - Streptococcus pneumoniae, S. pyogenes, and Staphylococcus aureus.

5. EPIDEMIOLOGY
Children 3 to 36 months of age, but is rare beyond age 6 years.
More common in boys, with a male:female ratio of about 1.4:1.
In the fall or early winter

6. PATHOGENESIS 
The viruses that cause croup typically infect the nasal and pharyngeal mucosal epithelia initially, and then spread locally along the respiratory epithelium to the larynx and trachea.
The anatomic hallmark of croup is narrowing of the trachea in the subglottic region.
Dynamic obstruction

7. PATHOGENESIS Host factors include: Anatomic narrowing of the airway
Hyperactive airways
Acquired airway narrowing from respiratory tract papillomas (human papillomavirus) or post intubation scarring.

8. CLINICAL PRESENTATION-Laryngotracheitis
Usually a gradual onset
Beginning with nasal irritation, congestion, and coryza.
Generally progress over 12 to 48 hours to include fever, hoarseness, barking cough, and stridor.
Rapid progression or signs of lower airway involvement suggests a more serious illness.
Symptoms typically persist for three to seven days with a gradual return to normal.
Agitation, which generally is accompanied by increased inspiratory effort, exacerbates the subglottic narrowing by creating negative pressure in the airway.

9. Rapid Assessment
General appearance (including the presence of stridor at rest)
Vital signs
Pulse oximetry
Airway stability
Mental status

10. Respiratory Failure Fatigue and listlessness Marked retractions
Decreased or absent breath sounds
Depressed level of consciousness
Tachycardia out of proportion to fever
Cyanosis or pallor
A tracheal tube that is 0.5 to 1 mm smaller than would typically be used may be required.
Immediate pharmacologic treatment, including administration of nebulized epinephrine and systemic or nebulized corticosteroids.

11. History Sudden onset of symptoms Rapidly progressing symptoms
Previous episodes of croup
Underlying abnormality of the upper airway
Medical conditions that predispose to respiratory failure (eg, neuromuscular disorders)
Fever
Hoarseness and barking cough
Difficulty swallowing
Drooling

12. Physical Examination Overall appearance
Quality of the voice — A muffled "hot potato" voice is suggestive of epiglottitis, retropharyngeal abscess, or peritonsillar abscess.
Degree of respiratory distress
Tidal volume — Does there appear to be good chest expansion with inspiration, indicating adequate air entry?
Lung examination
Assessment of hydration status

13. Physical Examination
Cherry red, swollen epiglottis, suggestive of epiglottitis
Pharyngitis, typically minimal in laryngotracheitis, may be more pronounced in epiglottitis or laryngitis
Excessive salivation, suggestive of acute epiglottitis, peritonsillar abscess, or retropharyngeal abscess
Diphtheritic membrane
Tonsillar asymmetry or deviation of the uvula suggestive of peritonsillar abscess
Midline or unilateral swelling of the posterior pharyngeal wall suggestive of retropharyngeal abscess

14. Severity Assessment — Westley croup score
Level of consciousness: Normal, including sleep = 0; disoriented = 5
Cyanosis: None = 0; with agitation = 4; at rest = 5
Stridor: None = 0; with agitation = 1; at rest = 2
Air entry: Normal = 0; decreased = 1; markedly decreased = 2
Retractions: None = 0; mild = 1; moderate = 2; severe = 3
Mild croup is defined by a Westley croup score of 2.
Moderate croup is defined by a Westley croup score of 3 to 7.
Severe croup is defined by a Westley croup score of 8.

15. DIFFERENTIAL DIAGNOSIS
Acute epiglottitis
Peritonsillar and retropharyngeal abscesses
Foreign body aspiration or ingestion
Acute angioneurotic edema
Upper airway injury
Congenital anomalies of the upper airway

16. Imaging - Steeple sign

17. Croup lateral neck radiograph

18. Epiglottitis

19. Bacterial tracheitis

20. Home Triage Stridor at rest An abnormal airway
Previous episodes of moderate to severe croup
Medical conditions that predispose to respiratory failure (eg, neuromuscular disorders)
Rapid progression of symptoms (less than 12 hours of illness)
Inability to tolerate oral fluids
Parental concern that cannot be relieved by reassurance
Prolonged symptoms (more than three to seven days) or an atypical course (perhaps indicating an alternative diagnosis)

21. Mild Croup & Home Treatment
Be treated symptomatically with humidity, fever reduction, and oral fluids.
Running hot water from the shower or exposure to cold night air
A follow-up phone call:
Difficulty breathing
Pallor or cyanosis
Severe coughing spells
Drooling or difficulty swallowing
Fatigue
Worsening course
Fever (>38.5ºC)
Prolonged symptoms (longer than seven days)
Stridor at rest
Suprasternal retractions

22. Mild Croup & Out-patient Tx
May have improvement with humidified air.
A single dose of oral dexamethasone (0.15 to 0.6 mg/kg, maximum dose 10 mg) may reduce the need for reevaluation, shorten the course, improve duration of the child's sleep, and reduce parental stress.
An anticipatory guidance

23. Moderate To Severe Croup
Administration of humidified air or humidified oxygen
Nebulized epinephrine
Any increase in anxiety may worsen airway obstruction
BMV and advanced airway techniques if the condition worsens
Monitoring respiration and consciousness
Fluids
Intubation - A tracheal tube that is 0.5 to 1 mm smaller than would typically be used may be required.

24. Moderate To Severe Croup
Dexamethasone (0.6 mg/kg, maximum of 10 mg), by the least invasive route possible : oral or IV. Repeat doses of corticosteroids are not necessary on a routine basis.
Nebulized budesonide (2 mg [2 mL solution] via nebulizer) - an alternative
Nebulized epinephrine - Racemic epinephrine as 0.05 mL/kg per dose (maximum of 0.5 mL) of a 2.25 percent solution diluted to 3 mL total volume with normal saline.
Observation - at least 3-4 hours

25. Discharge to Home Criteria
No stridor at rest
Normal pulse oximetry
Good air exchange
Normal color
Normal level of conscious
Demonstrated ability to tolerate fluids by mouth
Caregivers understand the indications for return to care and would be able to return if necessary
Before discharge, follow-up with the primary care provider should be arranged within the next 24 hours. Instructions regarding home treatment should be provided.

26. Hospitalization Need for supplemental oxygen
Moderate retractions and tachypnea, indicating increased work of breathing, which may lead to respiratory fatigue and failure
Degree of response to initial therapies
"Toxicity" or clinical picture suggesting serious secondary bacterial infection
Poor oral intake and degree of dehydration
Young age, particularly younger than 6 months
Ability of the family to comprehend the instructions regarding recognition of features that indicate the need to return for care
Ability of the family to return for care (eg, distance from home to care site, weather/travel conditions)
Recurrent visits to the ED within 24 hours

27. Prognosis
Symptoms of croup resolve in most children within three days, but may persist for up to one week.
Mortality is rare, occurring in <0.5 percent of intubated children.

28. Complications Uncommon: Hypoxemia and respiratory failure.
Pulmonary edema
Pneumothorax
Pneumomediastinum

29. Thank For Your Attention!!
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