RESP - Croup (Laryngotracheobronchitis)

Question 1

What is Croup?

Answer 1

Laryngotracheobronchitis. An acute URTI that causes oedema in the larynx.

Question 2

Epidemiology of Croup (3).

Answer 2

1. Affects kids between 6 months and 6 years of age.
2. Peak age of 2 years (6 months-3 years).
3. Commoner in Autumn.

Question 3

Aetiology of Croup.

Answer 3

1. Commonest : Parainfluenza (1-3; not 4) (80%).
2. Other : Influenza, Adenovirus, RSV.
3. Formerly : Diphtheria (vaccination) - leads to epiglottis and high mortality.

Question 4

Prognosis of Croup.

Answer 4

Improves in less than 48 hours and has a good response to steroid (especially Dexamethasone) treatment.

Question 5

Pathophysiology of Croup (3).

Answer 5

1. Subglottic oedema.
2. Inflammation.
3. Exudate.

Question 6

Clinical Features of Croup (5).

Answer 6

1. Stridor (caused by a combination of laryngeal oedema and secretions).
2. Increased work of breathing.
3. ‘Barking’ Cough (occurs in clusters of coughing episodes, worse at night).
4. Dysphonia.
5. Low-Grade Fever and Coryzal Symptoms.

Question 7

Clinical Features of MILD Croup (3).

Answer 7

1. Occasional barking cough.
2. No audible stridor at rest.
3. No or mild suprasternal and/or intercostal recession.

Question 8

Clinical Features of MODERATE Croup (4).

Answer 8

1. Frequent barking cough.
2. Easily audible stridor at rest.
3. Suprasternal and sternal wall retraction at rest.
4. No or little distress/agitation.

Question 9

Clinical Features of SEVERE Croup (6).

Answer 9

1. Frequent barking cough.
2. Prominent inspiratory (and occasionally expiratory) stridor at rest.
3. Marked sternal wall retractions.
4. Significant distress and agitation.
5. Lethargy or restlessness (sign of hyperaemia).
6. Tachycardia.

Question 10

Admission Criteria of Croup (4).

Answer 10

1. Child with Moderate or Severe Croup.
2. Child Below 6 months of age.
3. Child with known upper airway abnormalities e.g. Down’s, Laryngomalacia.
4. Uncertainty about Diagnosis.

Question 11

Radiology of Croup.

Answer 11

PA View CXR will show subglottic narrowing ‘Steeple Sign’.

Question 12

Management of Mild Croup (3).

Answer 12

1. At home with simple supportive treatment.
2. Avoid spread of infection.
3. Oral Dexamethasone.

Question 13

Management of Croup in Hospital (5).

Answer 13

ODA (Humidified Oxygen, Oral Dexamethasone, Nebulised Adrenaline).

1. Oral Dexamethasone (usually single dose of 0.15mg/kg that can be repeated after 12 hours) or use Prednisolone.
2. Oxygen.
3. Nebulised Budesonide.
4. Nebulised Adrenaline.
5. Intubation and Ventilation.

Question 14

Differential Diagnosis of Croup (1).

Answer 14

Bacterial Tracheitis - similar to viral croup but child has a high fever and rapidly progressive airway obstruction with copious thick airway secretions, caused by S. aureus, requiring IV antibiotics.