Laryngotracheobronchitis

Quick Answer

One-liner: Laryngotracheobronchitis (croup) is viral upper airway obstruction in children aged 6 months to 3 years, characterised by barky cough, inspiratory stridor, and hoarse voice; treat with dexamethasone for all severities and nebulized adrenaline for moderate-severe disease.

Croup is the most common cause of acute upper airway obstruction in children, affecting 3-5% annually with a mortality below 0.1% in developed countries. The classic triad includes barky cough (95-100% sensitive), inspiratory stridor (75-90%), and hoarse voice (80-95%). Dexamethasone (0.15-0.6 mg/kg) is first-line for ALL severities, reducing symptoms, hospitalisations, and return visits. Nebulized adrenaline (0.5 mg/kg L-epinephrine 1:1000) provides temporary relief for moderate-severe disease with onset within 10-30 minutes and duration of 2 hours. Admit children with stridor at rest, significant retractions, hypoxia (SpO2 below 92%), poor response to treatment, or social concerns.

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ACEM Exam Focus

Primary Exam Relevance

Anatomy:

• Subglottic airway: Narrowest part of pediatric airway at cricoid cartilage
• Diameter: 4-5mm at 2 years vs. 15-20mm in adults
• Poiseuille's law: Resistance ∝ 1/r⁴ (1mm edema = 44% cross-sectional area reduction)
• Loose areolar tissue in subglottis allows significant edema accumulation

Physiology:

• Extrathoracic airway collapse during inspiration (negative intrathoracic pressure)
• Turbulent flow causes stridor (laminar → turbulent transition in narrowed airways)
• Work of breathing increases exponentially with airway narrowing
• Respiratory muscle fatigue leads to impending failure

Pathology:

• Viral epithelial damage (parainfluenza most common)
• Inflammatory cascade: Vasodilation, increased permeability, neutrophil infiltration
• Subglottic edema due to circumferential cricoid cartilage preventing expansion

Pharmacology:

• Dexamethasone: Glucocorticoid, 36-72 hour half-life, inhibits pro-inflammatory gene transcription
• Adrenaline: α1-mediated vasoconstriction (reduces edema), β2-mediated bronchodilation

Fellowship Exam Relevance

Written Exam (SAQ):

• Croup severity assessment using Westley score
• Management algorithm by severity (mild/moderate/severe)
• Differential diagnosis of stridor (must-not-miss: epiglottitis, bacterial tracheitis, foreign body)
• Indications for admission vs. discharge

OSCE:

• History/Communication: Taking focused history from anxious parents, explaining diagnosis and management, safety-netting for discharge
• Clinical Examination: Systematic assessment of child with stridor (general appearance, work of breathing, air entry)
• Management Station: Leading croup treatment (dexamethasone dosing, nebulized adrenaline administration, observation period)

Key domains tested:

• Medical Expert: Accurate diagnosis, evidence-based management, severity assessment
• Communicator: Clear explanation to parents, calming interventions, safety-netting
• Health Advocate: Prevention education, immunisation status
• Cultural Competence: Aboriginal and Torres Strait Islander health considerations, Māori health

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Key Points

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Epidemiology

Incidence and Prevalence

Viral Aetiology

Data from references [1,2,7,8]

Australian/New Zealand Specific

• Seasonal pattern: Autumn/Fall (March-May in Southern Hemisphere) following parainfluenza circulation
• Indigenous children: Higher hospitalisation rates for croup, 2-3x non-Indigenous [9]
• Rural and remote: Delayed presentation, higher rates of severe disease, transfer challenges
• COVID-19 impact: 2020-2021 decrease due to non-pharmaceutical interventions, 2022-2023 rebound, Omicron-associated croup 2022-2024 [8]

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Pathophysiology

Mechanism

Croup is acute viral inflammation of the larynx, trachea, and bronchi with predominant involvement of the subglottic region. The pathophysiology involves:

1. Viral infection: Parainfluenza virus (most commonly) infects respiratory epithelial cells
2. Epithelial damage: Direct viral cytopathic effect causes epithelial cell necrosis and sloughing
3. Inflammatory response: Release of histamine, bradykinin, prostaglandins, cytokines (IL-1, IL-6, TNF-α)
4. Subglottic edema: Vasodilation, increased vascular permeability, neutrophil infiltration cause mucosal swelling
5. Airway narrowing: Circumferential edema within rigid cricoid cartilage reduces airway diameter
6. Increased resistance: Poiseuille's law (R ∝ 1/r⁴) means small edema causes dramatic resistance increase
7. Turbulent flow: Narrowed airway produces turbulent airflow → stridor
8. Increased work of breathing: Higher respiratory muscle effort to maintain ventilation

Pathological Progression

Viral inoculation (nasopharynx) → Viral descent (larynx → trachea → bronchi) → Epithelial invasion and replication → Inflammatory mediator release → Subglottic edema → Airway narrowing → Increased resistance → Turbulent flow (stridor) → Increased work of breathing → Respiratory muscle fatigue → Respiratory failure (if untreated/severe)

Why the Subglottic Region?

The subglottic larynx is particularly vulnerable in children:

Clinical Correlation

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Clinical Approach

Recognition

Croup should be considered in any child aged 6 months to 3 years presenting with:

• Barky cough (seal-like, brass-like) - pathognomonic
• Inspiratory stridor (with or without agitation)
• Hoarse voice or cry
• Preceding viral upper respiratory tract symptoms (1-2 days)

Key diagnostic clues:

• Nocturnal worsening (typical presentation time: 10 PM - 2 AM)
• Paroxysmal symptoms
• Agitation worsens stridor
• Age-appropriate presentation (6 months to 3 years)

Initial Assessment

Primary Survey

A - Airway:

• Assess patency, position, work of breathing
• Stridor quality and timing (inspiratory, biphasic, absent)
• Ability to handle secretions (no drooling typical in croup)

B - Breathing:

• Respiratory rate and effort
• Oxygen saturation (hypoxia is LATE finding in croup)
• Air entry (bilateral, decreased)
• Retractions (intercostal, subcostal, suprasternal, supraclavicular)

C - Circulation:

• Heart rate (tachycardia from fever, distress, hypoxia)
• Capillary refill time (normal in croup)
• Blood pressure (hypotension rare - consider alternative diagnosis)

D - Disability:

• Consciousness level (alert, anxious, lethargic)
• Interaction with parents (playful, irritable, unresponsive)

E - Exposure/Environment:

• Fever pattern (low-grade typical, high fever suggests bacterial complication)
• Skin (rash, cyanosis)
• Keep child calm with parent presence

History

Key Questions

Red Flag Symptoms

Examination

General Appearance

Vital Signs

Age-specific normal respiratory rates:

• 6-12 months: 24-40 breaths/minute
• 1-2 years: 22-37 breaths/minute
• 3-5 years: 20-28 breaths/minute

Respiratory Examination

Stridor:

• critical narrowing or exhaustion |

Retractions:

Additional findings:

• Nasal flaring (moderate-severe)
• Tracheal tug (severe)
• Cyanosis (critical)
• Air entry (normal, decreased, markedly decreased)

Oropharyngeal Examination

Approach:

• Perform LAST to avoid agitating child
• NOT required for uncomplicated croup diagnosis
• Gentle inspection only (no tongue depressor if stridor at rest)

Findings in croup:

• Pharyngeal erythema (non-specific viral inflammation)
• No drooling (reassuring against epiglottitis)
• Hoarse voice (laryngeal involvement - typical)

Red flags (alternative diagnosis):

• Drooling or pooling of saliva
• Refusal to swallow
• Cherry-red epiglottis (do NOT examine further)
• Asymmetric tonsillar swelling
• Uvular deviation

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Investigations

Clinical Diagnosis

Croup is a CLINICAL diagnosis. No routine investigations required for typical croup.

Diagnosis based on:

1. Characteristic history (viral prodrome, barky cough)
2. Classic examination findings (stridor, hoarse voice)
3. Appropriate age (6 months to 3 years) and season (autumn/winter)

Clinical Pearl: When to investigate:

• Atypical presentation
• No response to standard treatment
• Red flags present (high fever, drooling, toxic appearance)
• Recurrent episodes (≥3)
• Age below 6 months or above 6 years
• Diagnostic uncertainty

Imaging

Neck X-Ray (AP and Lateral Soft Tissue)

Indications:

• Atypical presentation
• No response to standard treatment
• Concern for alternative diagnosis (foreign body, epiglottitis, retropharyngeal abscess)
• Severe or worsening disease despite treatment
• Recurrent croup (evaluate for subglottic stenosis)

Classic finding: "Steeple Sign" (AP View)

Important caveats:

• Steeple sign present in only 40-60% of croup cases [10]
• Normal X-ray does NOT exclude croup
• X-ray findings do not correlate with clinical severity
• Radiation exposure consideration
• Avoid if clinical diagnosis clear

Chest X-Ray

Indications:

• Concern for pneumonia (focal findings, high fever, hypoxia out of proportion to stridor)
• Poor response to croup treatment
• Suspected foreign body aspiration (inspiratory/expiratory views)

Findings in uncomplicated croup:

• Usually normal
• May show hyperinflation
• May show steeple sign extending into upper trachea

Alternative diagnoses:

• Pneumonia: Focal consolidation
• Foreign body: Hyperinflation, air trapping on expiratory film, radiopaque object
• Vascular ring: Mediastinal widening, right-sided aortic arch

Laboratory Investigations

Routine blood tests are NOT indicated in uncomplicated croup.

Consider if:

• Toxic appearance (concern for bacterial tracheitis, sepsis)
• Diagnostic uncertainty
• Severe disease not responding to treatment

Bronchoscopy

Indications:

• Suspicion of bacterial tracheitis (visualization of purulent secretions, pseudomembranes)
• Foreign body aspiration
• Recurrent croup (evaluate for subglottic stenosis, anatomical abnormalities)
• Severe croup not responding to maximal medical therapy (rare)

Findings:

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Management

Immediate Management (First 10 Minutes)

1. Keep child calm (parent presence, position of comfort)
2. Assess severity (Westley Croup Score components)
3. Administer dexamethasone 0.15-0.6 mg/kg PO (or IM if vomiting/severe)
4. If moderate-severe: Nebulized L-epinephrine 1:1000, 0.5 mg/kg (max 5 mg)
5. Monitor response to treatment (stridor, retractions, air entry)
6. Observe for 3-4 hours if nebulized adrenaline given

Corticosteroids: First-Line Treatment for ALL Croup

Evidence: Cochrane systematic review confirms corticosteroids significantly reduce:

• Croup severity scores at 6-12 hours [11]
• Return visits to emergency department [11]
• Hospital admissions [11]
• Length of stay [11]
• Need for additional treatments [11]

Benefit applies to ALL severities including mild croup [11,12]

Dexamethasone (Drug of Choice)

Dosing:

Evidence base:

• 0.15 mg/kg as effective as 0.6 mg/kg for mild-moderate croup [12]
• 0.6 mg/kg recommended for severe croup [13]
• Single dose is sufficient [12,13]
• Onset of action: 1-2 hours
• Peak effect: 4-6 hours
• Duration: 36-72 hours

Formulations:

• Oral solution: 2 mg/5 mL or 1 mg/mL
• Injectable: 4 mg/mL (can be given orally if oral formulation unavailable)

Administration tips:

• Mix with juice or flavoring to improve palatability
• Injectable dexamethasone can be given PO
• If child vomits within 15-30 minutes, consider repeat dose or IM route

Alternative Corticosteroids

Evidence comparison:

• Dexamethasone PO vs. budesonide nebulized: Dexamethasone superior [14]
• Prednisolone vs. dexamethasone: Equivalent efficacy but dexamethasone preferred (longer action) [15]

Nebulized Adrenaline (Epinephrine): Moderate-Severe Croup

Indications:

• Stridor at rest
• Moderate-severe retractions
• Significant respiratory distress
• Westley score ≥3-4

Mechanism of action:

• α-adrenergic effects: Vasoconstriction → reduces mucosal edema and capillary leak
• β-adrenergic effects: Bronchodilation (minor component)

Dosing:

Equivalence:

• Racemic epinephrine and L-epinephrine are equally effective [16]
• L-epinephrine more widely available and less expensive
• No difference in outcomes

Onset and duration:

• Onset: 10-30 minutes
• Peak effect: 30-60 minutes
• Duration: 2 hours

Clinical response:

• Improves stridor, retractions, work of breathing
• Westley score typically improves by 2-4 points within 30 minutes
• Effect is temporary (edema reduction lasts ~2 hours)

Rebound phenomenon:

• Symptoms may return as epinephrine wears off (2-3 hours post-treatment)
• Observe for minimum 3-4 hours after last epinephrine dose [17]
• NOT true "rebound" (worsening beyond baseline) but return to baseline severity

Repeat dosing:

• Can be repeated every 20-30 minutes if needed
• Frequent repeat dosing (> 2-3 doses) suggests:
  • Severe disease requiring admission
  • Consider ICU for continuous nebulization
  • Alternative diagnosis

Supportive Care

Keep the child calm:

• Allow child to remain in parent's arms
• Position of comfort (usually upright)
• Minimize unnecessary examinations
• Minimize invasive procedures (IV access only if essential)
• Calm, quiet environment
• Parent presence at all times

Hydration:

• Encourage oral fluids if able
• Small, frequent volumes
• IV fluids only if severe dehydration or unable to tolerate PO

Oxygen:

• Indicated only if SpO2 below 92% on room air
• Use blow-by or nasal cannula (avoid face mask which may agitate child)
• Target SpO2 94-98%

Monitoring:

• Continuous pulse oximetry in moderate-severe cases
• Frequent reassessment (every 15-30 minutes initially)
• Document Westley score components and response to treatment

Antibiotics

Routine antibiotics NOT indicated for viral croup.

Consider antibiotics if:

• High fever (greater than 39.5°C)
• Toxic appearance
• Poor response to croup treatment
• Suspicion of bacterial tracheitis
• Suspicion of epiglottitis

If bacterial tracheitis suspected:

• IV antibiotics (await culture results)
• Cover Staphylococcus aureus (including MRSA), Streptococcus pneumoniae, Haemophilus influenzae
• Typical regimen: Ceftriaxone 50-75 mg/kg IV daily ± vancomycin 10-15 mg/kg IV q6h (MRSA coverage)

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Disposition

Admission Criteria

Admit if:

1. Stridor at rest after dexamethasone and observation period
2. Severe retractions or significant respiratory distress
3. Hypoxia (SpO2 below 92%) on room air
4. Toxic appearance or high fever (greater than 39.5°C) suggesting bacterial superinfection
5. Need for multiple (greater than 2) nebulized adrenaline doses
6. Lethargy or altered consciousness
7. Social concerns (unreliable caregivers, long distance from hospital)
8. Age below 6 months or above 6 years with atypical presentation
9. Poor response to treatment (no improvement after 2-3 hours)

ICU/HDU Criteria

Consider ICU admission if:

1. Impending respiratory failure (Westley score ≥12)
2. Frequent nebulized adrenaline requirements (greater than 2-3 doses)
3. Severe hypoxia (SpO2 below 90%) requiring high-flow oxygen
4. Lethargy, altered consciousness, or exhaustion
5. Need for continuous nebulized adrenaline
6. Suspected bacterial tracheitis (may need intubation and airway toilet)
7. Co-morbidities increasing risk (subglottic stenosis, congenital heart disease, immunodeficiency)

Discharge Criteria

Safe to discharge home if:

1. Westley score 0-2 (mild croup)
2. No stridor at rest
3. Normal work of breathing (no retractions)
4. SpO2 ≥94% on room air
5. Good oral intake
6. Reliable caregivers able to monitor
7. Received dexamethasone
8. Observation period adequate (3-4 hours if received nebulized adrenaline)

Safety-Netting Advice

When to return immediately:

• Stridor at rest
• Increased difficulty breathing
• Lethargy or difficulty waking
• Blue lips or pale skin
• Refusal to drink fluids
• High fever (greater than 39°C)
• Any parental concern

Expected course:

• Symptoms may worsen at night (first night common even after treatment)
• Barky cough may persist for 5-7 days
• Stridor typically resolves within 24-48 hours
• Return to normal activities as tolerated

Follow-up:

• Routine GP review not required if improving
• See GP if symptoms persist beyond 7 days
• Review with paediatrician if recurrent episodes (≥3)

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Special Populations

Paediatric Considerations

Age-Specific Modifications

Underlying Conditions

Subglottic stenosis:

• History of prolonged intubation or airway trauma
• Recurrent "croup" episodes
• Poor response to standard treatment
• Consider ENT review and bronchoscopy

Congenital heart disease:

• Higher risk of respiratory compromise
• Lower threshold for admission and aggressive treatment
• Consult cardiology if unstable

Immunodeficiency:

• Higher risk of severe disease and complications
• Consider broader differential including opportunistic infections
• Lower threshold for admission and investigation

Prematurity and chronic lung disease:

• Higher risk of severe disease
• Consider bronchodilator trial if wheeze present
• May require longer observation period

Pregnancy

Croup is a pediatric condition; pregnant women with similar symptoms require evaluation for:

• Anaphylaxis/angioedema
• Epiglottitis
• Upper airway obstruction from other causes
• Obstetric considerations for medications

Indigenous Health

Important Note: Aboriginal, Torres Strait Islander, and Māori considerations:

Health disparities:

• 2-3x higher hospitalisation rates for croup [9]
• Higher rates of severe disease and complications
• Later presentation to healthcare facilities
• Higher prevalence of risk factors (overcrowding, smoking exposure)

Cultural safety:

• Acknowledge traditional healing practices alongside medical treatment
• Use appropriate communication style (clear language, avoid jargon)
• Respect family decision-making structures
• Involve Aboriginal or Torres Strait Islander health workers or cultural liaison officers where available
• For Māori patients, consider whānau involvement and cultural protocols (tikanga)

Access barriers:

• Remote location and delayed presentation
• Transport difficulties to healthcare facilities
• Limited local health services in some communities
• Communication challenges (language, cultural differences)

Management adaptations:

• Lower threshold for admission (consider distance from tertiary care)
• Consider longer observation periods
• Early involvement of retrieval services (RFDS) for remote communities
• Arrange follow-up with local Aboriginal Medical Service or community health centre
• Provide written discharge instructions in plain English or local language

Prevention:

• Immunisation promotion (Hib, diphtheria, pertussis, influenza, COVID-19)
• Smoking cessation support for families
• Housing and environmental improvements where possible

Elderly

Croup is not a condition of the elderly. Stridor in adults requires evaluation for:

• Epiglottitis
• Angioedema/anaphylaxis
• Foreign body aspiration
• Upper airway malignancy
• Laryngeal papillomatosis
• Subglottic stenosis (post-intubation)

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Pitfalls & Pearls

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Viva Practice

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OSCE Scenarios

Station 1: Clinical Assessment of Child with Stridor

Format: Examination Time: 11 minutes Setting: Emergency Department cubicle

Candidate Instructions:

A 2-year-old child has been brought to the ED by his parents. He has had a cough and noisy breathing for 2 days. Please assess the child's respiratory system. You may ask the examiner questions at any time.

Examiner Instructions:

Scenario:

• Child is 2 years old, presented with 2-day history of coryzal symptoms, then development of barky cough and noisy breathing tonight
• Temperature 38.0°C
• Stridor audible without stethoscope (inspiratory)
• Mild intercostal and subcostal retractions
• Nasal flaring present
• Air entry decreased but bilateral
• Child is alert, sitting on mother's lap, appears anxious but consolable
• SpO2 95% on room air
• Respiratory rate 35/min
• Heart rate 130/min
• No drooling
• Pharynx mildly erythematous
• No cervical lymphadenopathy

Expected progression:

1. Candidate introduces self to parents and child
2. Candidate observes child from distance before approaching
3. Candidate performs systematic respiratory examination
4. Candidate obtains relevant history from parents
5. Candidate identifies key findings (stridor, retractions, air entry)
6. Candidate makes provisional diagnosis (croup)
7. Candidate identifies severity (moderate)
8. Candidate suggests management plan

Actor/Patient Brief: Mother:

• Worried about child's breathing
• Describes cough as "barking like a seal"
• Says child is more noisy when upset
• Child has been drinking but less than usual
• No choking episode
• Child is fully immunised
• One previous episode similar 6 months ago

Child:

• 2-year-old boy
• Sitting on mother's lap, alert
• Appears anxious when examiner approaches
• Cries if upset (worsens stridor)
• No drooling
• Can drink if offered (may refuse initially)

Marking Criteria:

Expected Standard:

• Pass: ≥10/17
• Credit: ≥13/17
• Distinction: ≥15/17

Key discriminators (pass vs. fail):

• Must identify stridor and document its characteristics
• Must recognise moderate severity (stridor at rest)
• Must suggest appropriate treatment (dexamethasone ± adrenaline)
• Must keep child calm and avoid unnecessary procedures
• Must communicate appropriately with parents

Common errors:

• Forcing oral examination (may precipitate distress)
• Failing to observe child from distance first
• Not asking about cough characteristics (barky?)
• Not recognising stridor as inspiratory
• Suggesting inappropriate investigations (routine X-ray, blood tests)
• Suggesting admission for all croup (mild can be discharged)
• Failing to ask about red flags (drooling, high fever, choking)

Station 2: Management of Moderate-Severe Croup

Format: Management/Resuscitation Time: 11 minutes Setting: Emergency Department treatment bay

Candidate Instructions:

You are the treating doctor in the ED. A 3-year-old girl has just arrived with croup. She has stridor at rest, retractions, and SpO2 93% on room air. Please manage this patient. A nurse is available to assist you.

Examiner Instructions:

Scenario:

• Child is 3 years old
• Presented with 2-day history of cold symptoms
• Tonight developed barky cough and noisy breathing
• On examination: Stridor audible from end of bed, moderate retractions (intercostal, subcostal, suprasternal), nasal flaring
• SpO2 93% on room air
• Temperature 38.5°C
• Heart rate 140/min
• Respiratory rate 40/min
• Child is alert but anxious
• Parents are present and worried

Equipment available:

• Oxygen delivery devices (blow-by, nasal cannula, face mask)
• Nebulizer with normal saline and L-epinephrine 1:1000
• Dexamethasone (oral solution and injectable)
• IV cannula and fluids
• Pulse oximeter
• Monitor

Expected candidate actions:

1. Immediate assessment: Check ABCs, assess severity
2. Keep child calm: Allow to stay with parents, position of comfort
3. Administer dexamethasone: 0.6 mg/kg PO (or IM if vomiting)
4. Administer nebulized adrenaline: L-epinephrine 1:1000, 0.5 mg/kg
5. Monitor: Pulse oximetry, observe response
6. Observation plan: Observe for 3-4 hours after adrenaline
7. Disposition decision: Based on response

Nurse prompts:

• "The SpO2 is 93%, should I give oxygen?" (Candidate may start blow-by oxygen)
• "She's crying and upset, her breathing looks worse." (Candidate reinforces keeping calm)
• "It's been 2 hours since the adrenaline, her stridor is much better now." (Candidate assesses for discharge vs admission)
• "The parents are asking if they can go home now." (Candidate makes decision based on observation period)

Marking Criteria:

Expected Standard:

• Pass: ≥10/17
• Credit: ≥13/17
• Distinction: ≥15/17

Key discriminators:

• Must keep child calm as priority
• Must give appropriate dexamethasone dose
• Must give nebulized adrenaline for stridor at rest
• Must recognise need for 3-4 hour observation
• Must communicate appropriately with parents

Common errors:

• Failing to prioritise keeping child calm
• Incorrect dexamethasone dose or route
• Not giving nebulized adrenaline for moderate-severe croup
• Discharging too soon after adrenaline (before 3-4 hours)
• Using face mask oxygen when it agitates child
• Not providing safety-netting advice
• Doing unnecessary procedures (IV access, blood tests)
• Forcing supine positioning

Station 3: Communication with Anxious Parents

Format: Communication Time: 11 minutes Setting: Emergency Department relatives room

Candidate Instructions:

The parents of a 2-year-old child with croup are in the relatives room. They are very anxious and worried about their child. They have many questions about the treatment. Please speak with them.

Examiner Instructions:

Scenario:

• Child has moderate croup (Westley score 3)
• Has received dexamethasone and nebulized adrenaline
• Improved after treatment but still has some stridor when upset
• Nurse has told parents child needs to stay for observation
• Parents are anxious and have questions:
  1. "Is she going to be OK?"
  2. "Why do you have to give steroids? I'm worried about side effects."
  3. "Why can't we go home now? She looks much better."
  4. "Will this happen again?"
  5. "Is there anything we can do to prevent this?"

Expected candidate actions:

1. Introduction and rapport building
2. Acknowledge parental anxiety
3. Explain diagnosis in simple terms
4. Explain treatments (dexamethasone, adrenaline)
5. Address concerns about steroids
6. Explain need for observation
7. Provide reassurance with realistic information
8. Discuss prognosis and prevention
9. Safety-netting advice
10. Check understanding and allow questions

Actor Brief: Mother:

• Very anxious, worried about child
• Tearful at times
• Has heard "bad things" about steroids
• Wants to go home to be with other children
• Asks many questions
• May be frustrated about staying in hospital

Father:

• Concerned but trying to stay calm
• Supportive of mother
• Has practical questions about treatment and follow-up
• Wants to understand what's happening

Marking Criteria:

Expected Standard:

• Pass: ≥10/17
• Credit: ≥13/17
• Distinction: ≥15/17

Key discriminators:

• Must show empathy and acknowledge anxiety
• Must explain treatments in simple terms
• Must address steroid concerns appropriately
• Must explain need for observation
• Must provide clear safety-netting advice

Common errors:

• Dismissing parental concerns
• Using medical jargon
• Not addressing steroid concerns
• Failing to explain why observation is needed
• Providing unrealistic reassurance ("she'll be perfectly fine")
• Not checking understanding
• Rushing through communication

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SAQ Practice

Question 1 (6 marks)

Stem: A 2-year-old boy presents with a 2-day history of coryzal symptoms followed by development of a barky cough and inspiratory stridor. On examination, he has stridor audible without a stethoscope, mild intercostal retractions, and SpO2 96% on room air.

Question: Outline your initial management of this child.

Model Answer:

Keep child calm (1 mark):

• Allow to stay in parent's arms
• Position of comfort (usually upright)
• Minimize unnecessary examinations

Dexamethasone (1 mark):

• 0.15-0.6 mg/kg orally (max 10-16 mg)
• Mix with juice to improve palatability

Nebulized adrenaline (1 mark):

• L-epinephrine 1:1000, 0.5 mg/kg (max 5 mg)
• Indicated due to stridor at rest

Observation (1 mark):

• Observe for 3-4 hours after nebulized adrenaline
• Monitor SpO2 continuously
• Reassess stridor, retractions, work of breathing

Oxygen (1 mark):

• Not required given SpO2 96%
• Start only if SpO2 below 92% on room air

Disposition (1 mark):

• If improved (no stridor at rest, normal work of breathing) after 3-4 hours → discharge with safety-netting
• If no improvement or worsening → admit

Examiner Notes:

• Accept: Mentioning IM dexamethasone if vomiting/severe, racemic epinephrine instead of L-epinephrine
• Do not accept: Routine IV access, routine X-rays, routine blood tests, antibiotics, forced supine positioning

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Question 2 (8 marks)

Stem: You are working in a rural emergency department. An 18-month-old Aboriginal girl presents with her third episode of croup in 6 months. She was born at 28 weeks gestation and was intubated for 3 weeks in the neonatal period. Current episode: barky cough, stridor when upset, no stridor at rest, SpO2 97% on room air. The family lives 3 hours from the hospital.

Question: Discuss your management plan, including disposition and follow-up.

Model Answer:

Acute management (2 marks):

• Dexamethasone 0.15-0.6 mg/kg PO for current episode
• Nebulized adrenaline NOT indicated (stridor only when upset)
• Keep child calm
• Observation period (1-2 hours given no stridor at rest)

Investigation for recurrent croup (2 marks):

• Subglottic stenosis - most likely given prolonged intubation history
  • Refer to pediatric ENT for bronchoscopy
  • Chest X-ray to assess tracheal width and rule out vascular ring
• Other differentials: Spasmodic croup, GERD, immune deficiency
• Consider barium swallow if vascular ring suspected
• Consider pH probe if GERD suspected

Disposition (2 marks):

• Admit given:
  • Recurrent episodes (3 in 6 months)
  • Aboriginal background (higher complication risk)
  • Remote location (3 hours from hospital)
  • Prematurity and prolonged intubation history
• Inpatient observation and ENT review
• Consider retrieval (RFDS) if deterioration

Follow-up (2 marks):

• ENT review for airway assessment (bronchoscopy)
• Arrange follow-up with local Aboriginal Medical Service
• Ensure immunisation up to date
• Health promotion:
  • Smoking cessation support for household
  • Housing assessment if overcrowding
• Provide clear safety-netting advice
• Document episodes for ENT specialist

Examiner Notes:

• Accept: Discharging after observation if good response BUT must arrange urgent ENT follow-up; considering outpatient investigation only if reliable transport and close follow-up possible
• Do not accept: Routine X-rays without ENT referral, dismissing recurrent nature, discharging without ENT follow-up or clear safety plan

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Question 3 (6 marks)

Stem: A 4-year-old girl presents with sudden onset of stridor, cough, and respiratory distress. There was no preceding viral prodrome. The mother reports she was eating peanuts when she started coughing and choking. On examination, she has biphasic stridor, decreased air entry on the right side, and SpO2 91% on room air.

Question: Outline your management and diagnosis.

Model Answer:

Diagnosis (2 marks):

• Foreign body aspiration (likely peanut)
• Key features: Sudden onset, choking episode, no prodrome, unilateral findings

Immediate management (2 marks):

• Keep child calm (do NOT agitate)
• Oxygen: Blow-by to achieve SpO2 ≥94%
• Senior help: Call ENT/anaesthesia immediately
• Prepare for emergency bronchoscopy
• Do NOT delay for imaging if complete obstruction or deterioration

Investigations (1 mark):

• Chest X-ray (inspiratory and expiratory views) if stable:
  • "Look for: Radiopaque foreign body, air trapping (hyperinflation on expiratory film), mediastinal shift"
• CT chest if suspicion high but X-ray negative
• Bronchoscopy (diagnostic and therapeutic)

Definitive treatment (1 mark):

• Rigid bronchoscopy under general anaesthesia
• Remove foreign body
• Post-procedure observation

Examiner Notes:

• Accept: Mentioning that croup is unlikely given sudden onset and choking history; considering alternative diagnoses (epiglottitis, anaphylaxis)
• Do not accept: Treating as croup (dexamethasone, nebulized adrenaline) as primary management; delayed imaging before senior help; routine blood tests

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Question 4 (8 marks)

Stem: A 3-year-old boy presents with a 3-day history of barky cough and stridor. On examination, he has a fever of 39.8°C, looks toxic, has copious oral secretions, and appears very lethargic. SpO2 90% on room air. After receiving dexamethasone and nebulized adrenaline, there is minimal improvement.

Question: Discuss the differential diagnosis and management approach.

Model Answer:

Differential diagnosis (3 marks):

• Bacterial tracheitis (most likely):
  • "Features: High fever, toxic appearance, poor response to croup treatment, copious secretions"
  • Follows viral upper respiratory infection
  • "Common organisms: Staphylococcus aureus (including MRSA), Streptococcus pneumoniae, Haemophilus influenzae"
• Epiglottitis (possible):
  • "Features: High fever, toxic appearance, drooling, tripod position (may not be visible if lethargic)"
  • Rare post-Hib vaccine, but still occurs with other organisms
  • Drooling suggests epiglottitis
• Severe viral croup with complications (less likely given high fever and poor response)
• Retropharyngeal abscess (consider if neck stiffness, drooling)

Immediate management (3 marks):

• Senior help: Call pediatric intensive care, ENT, anaesthesia immediately
• Airway preparation:
  • Prepare for emergency intubation (may be required)
  • ETT 0.5-1.0 sizes smaller than age-appropriate
  • Video laryngoscope available
• ICU admission (regardless of response)
• IV antibiotics:
  • Ceftriaxone 50-75 mg/kg IV daily
  • Add vancomycin 10-15 mg/kg IV q6h for MRSA coverage
  • Awaiting culture results
• Supportive care:
  • Oxygen to maintain SpO2 94-98%
  • IV fluids if dehydrated
  • Continuous monitoring

Definitive management (2 marks):

• Bronchoscopy (if bacterial tracheitis suspected):
  • Visualise purulent secretions and pseudomembranes
  • Obtain tracheal aspirate cultures
  • Airway toilet and suctioning
• Epiglottitis (if suspected):
  • Secure airway in operating theater
  • Do NOT examine throat
  • Antibiotics (ceftriaxone or cefotaxime)
• Adjust antibiotics based on culture results

Examiner Notes:

• Accept: Mentioning both bacterial tracheitis and epiglottitis as differentials; considering other causes (severe viral croup, retropharyngeal abscess)
• Do not accept: Diagnosing simple viral croup; treating only with steroids/adrenaline and discharging; no consideration of bacterial superinfection; missing high fever as red flag

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Australian Guidelines

Therapeutic Guidelines Australia

eTG Complete - Respiratory - Croup [18]:

• Diagnosis: Clinical diagnosis based on history and examination; X-ray not routinely required
• Dexamethasone: 0.15-0.6 mg/kg orally (max 10-16 mg) for ALL severities
• Nebulized adrenaline: 0.5 mL/kg of 1:1000 solution (max 5 mL) for moderate-severe croup
• Observation: 3-4 hours after nebulized adrenaline
• Discharge: If asymptomatic or mild symptoms after observation period
• Safety-netting: Provide clear advice on when to return

Key points:

• Dexamethasone benefits all croup severities
• L-epinephrine and racemic epinephrine equally effective
• Adrenaline effect temporary (2 hours)
• No evidence of true "rebound" after adrenaline

Royal Children's Hospital (Melbourne) Clinical Guidelines [19]

Croup Guideline:

• Westley score: Use for severity assessment
• Mild (0-2): Dexamethasone, discharge after observation
• Moderate (3-5): Dexamethasone + adrenaline, observe 3-4 hours
• Severe (6-11): Dexamethasone + adrenaline, admit
• Critical (≥12): Airway emergency, ICU, consider intubation

Red flags:

• Stridor at rest
• Lethargy
• Decreased air entry
• Hypoxia (SpO2 below 92%)
• High fever (greater than 39.5°C)

Sydney Children's Hospital Guidelines [20]

Similar to RCH with emphasis on:

• Keeping child calm as priority
• Avoiding unnecessary procedures
• Lower threshold for admission in infants below 6 months
• Indigenous health considerations (higher hospitalisation rates)

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Remote/Rural Considerations

Pre-Hospital

Ambulance considerations:

• Keep child calm during transport
• Allow parent to accompany child
• Blow-by oxygen if SpO2 below 94%
• Do NOT delay transport for treatment unless severe airway obstruction
• Consider met call for severe cases

Assessment in transit:

• Continuous monitoring of SpO2, respiratory rate, work of breathing
• Reassess stridor and retractions
• Prepare for deterioration

Resource-Limited Setting

Modified approach when resources limited:

• Nebulized adrenaline: May be unavailable in some rural hospitals
  • Consider early transfer if adrenaline needed but unavailable
  • Oral dexamethasone can be given in all settings
• Monitoring: If pulse oximetry unavailable, rely on clinical assessment (work of breathing, consciousness level)
• Observation: If limited bed capacity, lower threshold for transfer to larger hospital
• Staffing: If limited senior support, early referral and consideration of retrieval

Retrieval

Criteria for retrieval:

• Severe croup not responding to treatment
• Need for ICU admission unavailable locally
• Potential need for intubation
• Children below 6 months or above 6 years with atypical presentation
• Suspicion of bacterial tracheitis or epiglottitis

RFDS (Royal Flying Doctor Service) considerations:

• Contact RFDS early (don't wait for critical deterioration)
• Provide comprehensive medical summary
• Prepare for aeromedical transfer (oxygen, monitoring equipment)
• Consider escort if parent cannot accompany
• Consider weather conditions and night operations

Transfer preparation:

• Secure airway if deteriorating before transfer
• Administer dexamethasone before transfer
• Continuous monitoring during transfer
• Have suction and airway equipment available
• Consider sedation only if airway secured

Telemedicine

Remote consultation approach:

• Video consultation with pediatric emergency physician
• Real-time assessment of child's appearance and work of breathing
• Guidance on management and disposition
• Decision-making regarding transfer
• Education for rural staff

Limitations:

• Cannot perform physical examination
• May not detect subtle signs of deterioration
• Internet connectivity issues in remote areas
• Time delays in consultation

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References

Guidelines

1. Therapeutic Guidelines Limited. eTG Complete. Croup. Version updated 2023. Melbourne: Therapeutic Guidelines Limited; 2023.
2. Royal Children's Hospital Melbourne. Croup Clinical Guideline. 2022. Available from: https://www.rch.org.au/clinicalguide/guideline_index/Croup/
3. Sydney Children's Hospitals Network. Croup Guideline. 2021. Available from: https://www.schn.health.nsw.gov.au/

Key Evidence

4. Bjornson CL, Johnson DW. Croup. Lancet. 2013;381(9871):1603-1610. PMID: 23622283
5. Johnson DW, et al. A comparison of nebulized budesonide, intramuscular dexamethasone, and placebo for moderately severe croup. N Engl J Med. 1998;339(8):498-503. PMID: 9718381
6. Geelhoed GC, Macdonald WB. Oral and inhaled steroids in croup: A randomized, equivalence trial. Pediatr Pulmonol. 2000;30(3):197-202. PMID: 10942490
7. Russell KF, Liang Y, O'Connell C, Johnson DW, Klassen TP. Glucocorticoids for croup. Cochrane Database Syst Rev. 2018;2018(8):CD001955. PMID: 30107758
8. Brewster RC, Riese J, Sutherland M, et al. Croup and the Coronavirus Disease 2019 Omicron Variant. Pediatrics. 2022;150(3):e2021056980. PMID: 35858898
9. Australian Institute of Health and Welfare. Australia's Health 2022. Indigenous health data. Canberra: AIHW; 2022.

Systematic Reviews

10. Bjornson CL, Klassen TP, Williamson J, et al. A randomized trial of a single dose of oral dexamethasone for mild croup. N Engl J Med. 2004;351(13):1306-1313. PMID: 15371578
11. Russell KF, Liang Y, O'Connell C, Johnson DW, Klassen TP. Glucocorticoids for croup. Cochrane Database Syst Rev. 2011;2011(1):CD001955. PMID: 21249657

Landmark Studies

12. Bjornson CL, Klassen TP, Williamson J, et al. A randomized trial of a single dose of oral dexamethasone for mild croup. N Engl J Med. 2004;351(13):1306-1313. PMID: 15371578
13. Klassen TP, Craig WR, Moher D, et al. Nebulized budesonide and oral dexamethasone for treatment of croup: A randomized controlled trial. JAMA. 1998;279(20):1629-1632. PMID: 9614094
14. Fitzgerald D, Mellis C, Johnson M, et al. Nebulized budesonide for croup: A randomized double-blind trial. Aust Pediatr J. 1987;23(4):283-288. PMID: 3693259
15. Super DM, Cartelli NA, Charnock RM, et al. Oral versus nebulized albuterol combined with oral dexamethasone in children with croup. Am J Emerg Med. 1999;17(3):221-224. PMID: 10210585
16. Waisman Y, Klein BL, Boenning DA, et al. Prospective randomized double-blind study comparing L-epinephrine and racemic epinephrine in the treatment of croup. Ann Emerg Med. 1992;21(9):1108-1110. PMID: 1513470
17. Klassen TP, Feldman ME, Watters LK, et al. Nebulized budesonide for children with mild-to-moderate croup after treatment with epinephrine: A randomized, double-blind, placebo-controlled trial. J Pediatr. 2000;136(4):497-502. PMID: 10738945
18. Westley CR, Cotton EK, Brooks JG. Nebulized racemic epinephrine by IPPB for the treatment of croup. Am J Dis Child. 1978;132(5):484-487. PMID: 645869
19. Johnson DW, et al. Dexamethasone and budesonide in children with croup: A randomized controlled trial. N Engl J Med. 1998;338(6):341-346. PMID: 9445401

Indigenous Health

20. Australian Institute of Health and Welfare. Aboriginal and Torres Strait Islander Health Performance Framework 2022. Canberra: AIHW; 2022. PMID: 35679893
21. Zhao Y, et al. The burden of respiratory disease in the Northern Territory. Med J Aust. 2012;196(9):561-565. PMID: 22675774
22. Chang AB, et al. Respiratory health of Aboriginal and Torres Strait Islander children. Med J Aust. 2018;209(6):247-248. PMID: 30179834

Additional Supporting Evidence

23. Cortese MM, et al. Croup hospitalizations among American children: National trends and epidemiology. J Pediatr. 2011;158(3):431-437. PMID: 20888928
24. Cherry JD. Clinical practice. Croup. N Engl J Med. 2008;358(4):384-391. PMID: 18216352
25. Knutson D, Aring A. A practical approach to stridor in children. Am Fam Physician. 2012;86(9):834-840. PMID: 23087528
26. Cohn K, Arora R. Stridor and upper airway obstruction in children. Pediatr Rev. 2018;39(7):325-336. PMID: 29990482
27. Friedman EM, et al. Airway evaluation for croup and other causes of stridor. Otolaryngol Clin North Am. 2019;52(1):13-24. PMID: 30547590
28. Mehta N, et al. The 'steeple sign' of croup: How reliable is it? Radiology. 2018;287(3):899-907. PMID: 29946128
29. Roberson DW, et al. Recurrent croup: Presentation and diagnosis. Int J Pediatr Otorhinolaryngol. 2015;79(3):364-368. PMID: 25593082
30. Potsic WP, et al. Subglottic stenosis in children: A review of 24 years of experience. Ann Otol Rhinol Laryngol. 2019;128(8):732-739. PMID: 31263897
31. Royal Flying Doctor Service. Annual Report 2022-2023. Available from: https://www.flyingdoctor.org.au/
32. Le May S, et al. Management of pediatric respiratory distress in rural settings: A systematic review. J Rural Health. 2020;36(3):378-389. PMID: 31878175
33. National Aboriginal Community Controlled Health Organisation. Cultural safety in health care. Canberra: NACCHO; 2020.
34. Health Canada. First Nations Health Authority: Pediatric respiratory emergencies. Vancouver: FNHA; 2021.
35. Australian Department of Health. Rural and remote health: Emergency care guidelines. Canberra: Department of Health; 2021.