1. The Child with Stridor 1: Acute Stridor
Chris Kingsnorth

2. Before We Begin

3. Overview Definition of stridor Differential diagnoses: Croup
Acute epiglottitis
Bacterial tracheitis
Foreign body aspiration
Laryngomalacia
Subglottic stenosis

4. Stridor
“…High-pitched breath sound resulting from turbulent air flow secondary to narrowing in the upper airway…”
Most commonly the larynx
(Inspiratory and expiratory stridor in a 13-month child with croup)

5. Stridor Timing of stridor suggests the level of narrowing:
Inspiratory: Laryngeal region
Expiratory: Tracheobronchial region
Biphasic: Subglottic/glottic region

6. Differential Diagnoses
Acute
Croup
Acute epiglottitis
Bacterial tracheitis
Foreign body
Chronic
Laryngomalacia
Subglottic stenosis

7. History Time course (acute vs. chronic) Coryzal Sx / fever Cough
Drooling/ dysphagia
Cyanosis/ apnoeas
Possibility of FB aspiration (e.g. toys)
Nature of stridor: timing, soft vs. harsh, present at all times vs. only when distressed

8. ! Examination RR + effort (recession, tracheal tug) Confusion Cyanosis
Drooling
Cough
Chest examination
Never examine throat of child with severe stridor; this may precipitate acute airway obstruction !

9. Investigations If suspected epiglottitis/ respiratory failure:
Bloods (FBC, U+E, CRP)
ABG (respiratory failure, lactate)
Blood cultures
CXR

10. Acute Stridor: Croup

11. Croup: Epidemiology A.k.a acute laryngotracheobronchitis
Most common cause of acute stridor
3 months  6 yrs (peak at 2 yrs)
M > F
Peak in Autumn months
80% = Parainfluenza virus (others inc. RSV, Rhinovirus)

12. Croup: Natural History
Coryza + fever ↓
Stridor
Hoarse voice
Barking cough
Wheeze
Time course = days
Larynx
Trachea
Bronchi
Seal-like cough; usually worse at night

13. Croup: Clinical Features
Stridor
Hoarse voice
Barking cough
Wheeze
Tachypnoea +/- recessions, tracheal tug
Cyanosis if severe
May not cough during consultation (worse at night)
Child with croup. Note tachypnoea, barking cough, intercostal and subcostal recession, stridor and wheeze. Mild nasal flaring also visible.

14. Croup: Clinical Features
Video showing spectrum of clinical features in mild, moderate and severe croup

15. Croup: Investigations
Not required in most cases
Unless unable to rule out epiglottitis

16. Croup: Severity
Originally developed for research purposes; management should based on clinical assessment

17. Croup: Management Often resolves spontaneously
Mild cases can be managed at home with good hydration, paracetamol and a single dose of oral corticosteroid
If more severe may require admission, O2, nebulised adrenaline and IV hydration
Elective intubation if deteriorates
Recurrent croup may suggest subglottic stenosis

18. Acute Stridor: Acute Epiglottitis

19. Acute Epiglottitis: Epidemiology
Life-threatening Paediatric emergency
2-7 years
Most commonly bacterial infection
H. influenzae
Rare (HiB immunisation)

20. Acute Epiglottitis: Clinical Features
Pyrexia
Drooling
Inability to swallow
Stridor
Characteristic tripod position
Cough rare
Can progress from presentation to death within hours

21. Acute Epiglottitis: Clinical Features
Video showing clinical features of a young boy with acute epiglottitis. Note absence of cough and swallowing

22. Acute Epiglottitis: Management and Investigation
Priority = protect and secure the airway:
Do not examine throat
Do not lie child down
Avoid any examination/ investigations that will upset patient until after intubation
May precipitate acute airway obstruction

23. Acute Epiglottitis: Management and Investigation
Intubation
Laryngoscopy (oedematous, cherry-red epiglottis)

24. Acute Epiglottitis: Management and Investigation
Blood cultures
Antibiotics (Cefotaxime; chloramphenicol if penicillin allergy)
Lateral radiograph of the larynx shows ‘thumb sign’ (E) due to thickening of epiglottis

25. Acute Epiglottitis: Prognosis
Recovery rapid with treatment
Many children extubated within 48 hours of Abx

26. Acute Stridor: Bacterial Tracheitis

27. Bacterial Tracheitis: Epidemiology and Clinical Features
Rare
3 wks – 16yrs
Presents like croup with high fever but no response to standard croup Rx
Hypothesis = viral infection with mucosal damage +/- local immunosuppression predisposes to bacterial infection
S. aureus, S. pyogenes, S. pneumoniae, Moraxella, H. influenzae

28. Bacterial Tracheitis: Investigations and Management
Direct visualization and culture of purulent tracheal secretions via laryngotracheobronchoscopy only definitive means of diagnosis
Blood cultures
Antibiotics (Cefotaxime)
May require airway support

29. Acute Stridor: Foreign Body

30. Foreign Body: Epidemiology
Can be life threatening depending on level and severity of obstruction
To cause stridor must be lodged in upper airway (lower obstruction  wheeze)
Toddlers (mobile + dextrous)
Peanuts, small toys, beads, buttons etc
History usually suggests FB aspiration
Most common site = R main bronchus

31. Foreign Body: Clinical Features
Stridor if significant upper airway obstruction
Choking
Cough
Unilateral wheeze
Respiratory distress
Localised dull percussion of distal lung collapsed

32. Foreign Body: Investigations and Management
Bronchoscopy
CXR

33. Foreign Body: Emergency Management of Choking

34. What Now? Download slides/ notes pages
Online MCQ:
Request a Podcast/ ask a question
The Child with Stridor 2: Chronic Stridor

35. References
Stridor sound clip:
Laryngoscopy images: and

36. References
Bronchoscopy image:
FB CXR:
Choking algorithm: