Acute Epiglottitis

1. Clinical Overview

Summary

Acute Epiglottitis is a life-threatening, rapidly progressive bacterial infection of the epiglottis and supraglottic tissues. It causes massive oedema which can lead to abrupt, total airway obstruction within hours of symptom onset. Historically caused by Haemophilus influenzae type b (Hib), its incidence has plummeted in children by more than 95% due to widespread vaccination programs introduced in the 1990s, but it remains a critical emergency in unimmunised children and has shown an epidemiological shift toward adults. [1,2,3]

Management is defined by a fundamental safety principle: Secure the Airway First. Any intervention that disturbs the child—including throat examination, venipuncture, or radiological investigation—can precipitate complete airway obstruction and cardiorespiratory arrest. [4,5]

Key Facts

• The "Silent Killer": Unlike the characteristic barking cough of viral croup, children with epiglottitis are often remarkably quiet. They do not cough vigorously. They sit perfectly still, conserving every breath to maintain marginal airway patency.
• Microbiology:
  • Pre-vaccine era (before 1992): Hib accounted for >90% of cases.
  • Post-vaccine era (after 2000): Group A Streptococcus (Streptococcus pyogenes), Streptococcus pneumoniae, Staphylococcus aureus (including MRSA), and Non-typeable Haemophilus influenzae dominate. [6,7]
  • Rare causes include viral (HSV, varicella), fungal (in immunocompromised), and traumatic etiologies.
• Epidemiological Shift: Epiglottitis is now more common in adults than children in high-vaccination countries. Adult presentation differs: severe odynophagia (painful swallowing) with a normal-appearing oropharynx on routine inspection. [8,9]
• Mortality: Historical mortality approached 6-10% before modern airway management; with contemporary protocols (early airway intervention, multidisciplinary team), mortality is less than 1%. [10]

Clinical Pearls

The "Hands Off" Rule: Never attempt to examine the throat with a tongue depressor, spatula, or direct laryngoscope in a child presenting with stridor plus drooling in the emergency department. This can precipitate laryngospasm, total obstruction, and immediate cardiorespiratory arrest. The child must remain calm, undisturbed, typically on the parent's lap, with no attempts at cannulation or agitation until the senior airway team (consultant anaesthetist and ENT surgeon) is assembled and prepared for emergency intubation or surgical airway. [4,11]

Tripod Position: The pathognomonic posture—child sitting upright, leaning forward, neck extended (the "sniffing the morning air" position), mouth open, tongue protruding, chin thrust forward—maximises the anterior-posterior diameter of the supraglottic airway. Forcing the child to lie supine (e.g., for CT imaging or clinical examination) collapses the airway lumen and can precipitate arrest. [12]

Croup vs Epiglottitis (The Classic Differential):

Feature	Viral Croup	Acute Epiglottitis
Onset	Gradual (days)	Abrupt (hours)
Prodrome	Coryzal symptoms	None or minimal
Cough	Loud, barking, seal-like	Absent or minimal
Voice	Hoarse	Muffled ("hot potato")
Fever	Low-grade (less than 38.5°C)	High (>38.5°C, often >39°C)
Drooling	Rare	Common (80%)
Appearance	Generally well	Toxic, frightened
Position	Any	Tripod (sitting forward)
Stridor	Loud, worsens with agitation	Soft, may be minimal at rest

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2. Epidemiology

Demographics

• Paediatric Incidence (Pre-vaccination): In the 1980s, incidence was approximately 3-6 per 100,000 children under 5 years. [13]
• Paediatric Incidence (Post-vaccination): By 2010, incidence had fallen to less than 0.5 per 100,000 children in countries with high Hib vaccine coverage (UK, USA, Australia). [14,15]
• Peak Age (Children): Median age 2-5 years, with a range of 6 months to 12 years.
• Adult Incidence: Now surpasses paediatric incidence in developed nations, with rates of 1-4 per 100,000 adults. Median age 40-50 years. [8,16]
• Seasonal Variation: No strong seasonal pattern, unlike viral croup (winter predominance).
• Risk Factors:
  • Incomplete or absent Hib vaccination (unvaccinated children, recent immigrants, religious exemptions).
  • Immunocompromise: HIV, chemotherapy, congenital immunodeficiency.
  • Adults: Diabetes mellitus, smoking, chronic alcohol use, recent upper respiratory tract infection. [17]

Vaccination Impact

The Hib conjugate vaccine (introduced in the UK in 1992, USA in 1987) is one of the most successful public health interventions of the 20th century. It is administered as part of the routine immunisation schedule (at 8, 12, 16 weeks, with a booster at 1 year in the UK). Vaccine efficacy exceeds 95%. [18]

Post-vaccination, most paediatric cases are due to:

• Vaccine failures (rare, less than 5%).
• Unvaccinated children (parental refusal, missed appointments).
• Non-Hib pathogens (Group A Strep, pneumococcus, non-typeable Haemophilus).

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3. Pathophysiology

Anatomical Considerations

The epiglottis is a leaf-shaped fibrocartilaginous structure covered by highly vascular, loose areolar mucosa. It sits at the laryngeal inlet, anterior to the aryepiglottic folds. In children, the epiglottis is relatively larger and more omega-shaped than in adults, and the larynx is positioned higher (C3-4 level vs C4-5 in adults), contributing to the greater risk of obstruction. [19]

Mechanism of Disease Progression

The pathological sequence unfolds over 6-24 hours:

1. Bacterial Colonisation and Invasion: Nasopharyngeal colonisation with Hib or other pathogens leads to bacteraemia. Haematogenous seeding of the supraglottic mucosa occurs.
2. Acute Cellulitis: Intense inflammatory response in the epiglottis, aryepiglottic folds, and arytenoids causes rapid oedema. The loose submucosal tissue allows massive fluid accumulation.
3. Mechanical Obstruction: The swollen epiglottis becomes cherry-red, enlarged to 3-5 times normal size, curling posteriorly and inferiorly. During inspiration, negative intrathoracic pressure draws the inflamed epiglottis downward, acting as a ball-valve over the laryngeal inlet.
4. Progressive Hypoxia: As the airway lumen narrows, work of breathing increases exponentially (Poiseuille's Law: resistance is inversely proportional to the fourth power of the radius). Eventually, fatigue and hypoxia lead to hypoventilation, hypercapnia, bradycardia, and arrest.

Systemic Effects

• Bacteraemia: Blood cultures are positive in 50-90% of Hib cases. Septicaemia contributes to toxicity.
• Secondary Infections: Concurrent meningitis (10-15% of Hib epiglottitis cases), pneumonia, septic arthritis, and pericarditis may occur. [20]

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4. Clinical Presentation

Timeline

• Onset: Typically over 6-12 hours (range 2-24 hours).
• Progression: Rapid deterioration. The child who was speaking at breakfast may be in extremis by lunchtime.

The 4 D's (Classic Tetrad)

1. Drooling: Present in approximately 80% of children. Severe odynophagia (pain on swallowing) prevents the child from swallowing saliva, which pools and drips from the mouth.
2. Dysphagia: Extreme sore throat. The child refuses food and fluids.
3. Dysphonia: Voice is muffled or soft, described as "hot potato voice" (as if speaking with a hot object in the mouth). Distinct from the hoarse voice of croup (which is subglottic).
4. Distress: Marked anxiety, air hunger, restlessness, or paradoxical stillness (to conserve airway). Inspiratory stridor may be present, but can be soft or absent if obstruction is near-complete.

Additional Clinical Features

• High Fever: Temperature >38.5°C, often >39°C. Rigors may occur.
• Toxic Appearance: Pale, mottled, clammy skin. Lethargic or anxious. Tachycardic.
• Respiratory Distress: Subcostal, intercostal, and suprasternal recess indrawing. Nasal flaring. Use of accessory muscles.
• Stridor: Often surprisingly soft. Complete silence ("silent stridor") is an ominous sign indicating near-total obstruction.
• Cyanosis: Late sign, indicating imminent arrest.

Adult Presentation (Distinct Features)

• Severe sore throat ("worst sore throat of my life").
• Normal-appearing oropharynx on simple inspection with tongue depressor (oedema is supraglottic, not visible).
• Odynophagia, drooling.
• Muffled voice.
• Adults generally have larger airways and tolerate oedema better; intubation rates are lower (~50% vs >90% in children), but close observation in ICU/HDU is mandatory. [8]

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5. Clinical Examination

Guiding Principle

Minimise Disturbance. Do Not Examine the Throat.

General Inspection

• Position: Tripod position (sitting upright, leaning forward, hands on knees, neck extended).
• Appearance: Toxic, anxious, frightened facial expression. Drool visible at mouth.
• Respiratory Rate: Tachypnoea (rate often >40-60/min in young children).
• Colour: Pale or mottled (poor perfusion).

Airway Assessment (Observe Only)

• Stridor: Listen from a distance. Inspiratory stridor suggests supraglottic or glottic obstruction.
• Phonation: Muffled voice (supraglottic pathology) vs hoarse voice (glottic/subglottic pathology).
• Cough: Absent or minimal (vs barking cough in croup).

Cardiovascular

• Heart Rate: Tachycardia (compensatory) or bradycardia (pre-arrest sign).
• Blood Pressure: May be normal initially; hypotension is a late, ominous sign.

Do NOT Perform

• ❌ Throat examination with tongue depressor or laryngoscope (risk of precipitating total obstruction).
• ❌ Supine positioning (closes airway).
• ❌ Venipuncture or cannulation in an agitated child (postpone until theatre if unstable).
• ❌ Forcing oxygen mask on an uncooperative child (allow wafting or blow-by oxygen if tolerated).

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6. Investigations

Fundamental Rule

Do Not Delay Airway Intervention for Investigations

First-Line Investigations (ONLY if Diagnosis Uncertain and Patient Stable)

Lateral Soft Tissue Neck X-ray

• Indications: Only if child is stable, cooperative, and diagnosis is genuinely unclear (not in typical presentations).
• Classic Signs:
  • Thumb Sign: Swollen epiglottis resembles a thumb (normal epiglottis is thin, like a little finger).
  • Vallecula Sign: Obliteration of the normal air pocket in the vallecula (the space between the base of tongue and epiglottis).
• Limitations: Sensitivity ~80-90%. False negatives occur. Does not change immediate management (airway first).
• Safety: A senior doctor (ideally anaesthetist) must accompany the child to radiology. Resuscitation equipment must be immediately available.

Blood Tests

Typically deferred until airway is secured, but if obtained:

• Full Blood Count: Leukocytosis (WCC often 15-30 × 10⁹/L) with neutrophilia.
• CRP: Elevated (often >100 mg/L).
• Blood Cultures: Positive in 50-90% of Hib cases. Take before antibiotics if possible, but do not delay treatment.

Gold Standard Investigations (Performed in Theatre After Airway Secured)

Direct Laryngoscopy

• Diagnostic and Therapeutic: Performed during intubation under general anaesthesia.
• Findings: "Cherry-red" epiglottis, massively swollen (3-5 times normal size), oedematous aryepiglottic folds, arytenoid oedema.
• Confirmatory: Direct visualisation is the definitive diagnostic test.

Microbiological Cultures

• Epiglottic Swab: Taken after intubation (not before). Highest yield for causative organism.
• Blood Cultures: As above.
• Sputum/Tracheal Aspirate: If intubated and ventilated.

Additional Investigations (If Secondary Complications Suspected)

• Lumbar Puncture: If concurrent meningitis suspected (altered consciousness, seizures).
• Chest X-ray: If pneumonia suspected (consolidation, effusion).

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7. Management

Management Algorithm (Comprehensive)

         CHILD WITH STRIDOR + DROOLING + TOXIC APPEARANCE
                           ↓
              SUSPECT ACUTE EPIGLOTTITIS
                           ↓
        DO NOT UPSET / DO NOT EXAMINE THROAT
      (Keep child on parent's lap, sitting upright,
       calm environment, wafting oxygen if tolerated)
                           ↓
                  EMERGENCY CALL (2222)
     (Summon: Senior Anaesthetist + ENT Surgeon + 
      Senior Paediatrician/Emergency Physician)
                           ↓
          DO NOT DELAY FOR X-RAY OR BLOOD TESTS
                           ↓
              TRANSFER DIRECTLY TO THEATRE
       (Avoid supine position; parent accompanies if helpful)
                           ↓
         INHALATIONAL INDUCTION (Spontaneous Ventilation)
      (Sevoflurane or Halothane while child remains sitting;
       gradual transition to supine as depth increases)
                           ↓
         VIDEO LARYNGOSCOPY / DIRECT LARYNGOSCOPY
      (Prepare smaller endotracheal tube: 0.5-1.0 mm ID smaller)
                           ↓
              INTUBATION (First Attempt by Most Experienced)
      (ENT surgeon scrubbed, ready for immediate surgical airway)
                           ↓
      IF INTUBATION SUCCESSFUL → Secure tube, admit PICU
      IF INTUBATION FAILED → Rigid bronchoscopy (ENT)
      IF CANNOT INTUBATE/VENTILATE → Front of Neck Access
                           (cricothyroidotomy or emergency tracheostomy)
                           ↓
              SECURE TUBE & TRANSFER TO PICU
      (IV Antibiotics + IV Steroids + IV Fluids + Sedation)
                           ↓
              MECHANICAL VENTILATION (24-72 hours)
      (Monitor for cuff leak before extubation)

Detailed Management Steps

1. Pre-Hospital and Emergency Department Management

DO:

• ✅ Keep child calm and comfortable (on parent's lap if possible).
• ✅ Allow child to maintain position of comfort (usually sitting upright).
• ✅ Administer oxygen by wafting or blow-by (if tolerated; do not force mask).
• ✅ Call for senior help immediately (senior anaesthetist, ENT surgeon, senior paediatrician).
• ✅ Prepare for emergency transfer to theatre.
• ✅ Nil by mouth.

DO NOT:

• ❌ Examine the throat.
• ❌ Force child to lie down.
• ❌ Insert IV cannula (unless child is completely cooperative and stable).
• ❌ Perform venipuncture or blood tests.
• ❌ Send child for X-rays unaccompanied.
• ❌ Agitate or upset the child in any way.

2. Airway Management (Theatre)

Multidisciplinary Team Required:

• Senior Consultant Anaesthetist (paediatric anaesthesia experience).
• Senior ENT Surgeon (ready for surgical airway).
• Theatre Scrub Team (tracheostomy set open and ready).
• Operating Department Practitioner (ODP).
• Paediatric ICU Team (for post-intubation care).

Induction Technique (Gold Standard):

• Inhalational Induction with Spontaneous Ventilation: Sevoflurane in 100% oxygen (or halothane if available).
• Position: Child may remain semi-upright initially, gradually transitioned to supine as anaesthetic depth increases.
• Maintain Spontaneous Respiration: Avoid muscle relaxants until airway is definitively secured (muscle relaxation abolishes airway tone and can precipitate complete obstruction).
• IV Access: Establish once child deeply anaesthetised.

Intubation:

• Laryngoscopy: Direct laryngoscopy or video laryngoscopy (video preferred for visualisation and teaching).
• Tube Size: Use endotracheal tube 0.5-1.0 mm internal diameter (ID) smaller than predicted for age (due to airway oedema).
  • Example: Normal 4-year-old = 5.0 mm ID tube; use 4.0-4.5 mm ID in epiglottitis.
• Tube Type: Cuffed tube allows monitoring for cuff leak test (predicts safe extubation).
• First Attempt: Most experienced operator.
• Visualisation: Expect to see massively swollen, cherry-red epiglottis obscuring laryngeal inlet. Gentle manipulation; avoid trauma.

If Intubation Difficult or Failed:

• Plan B: Rigid bronchoscopy by ENT surgeon (bypasses supraglottic obstruction).
• Plan C: Front of Neck Access (FONA):
  • Cricothyroidotomy (surgical or cannula) for older children (>8 years).
  • Emergency Tracheostomy for younger children (cricothyroid membrane too small).
  • ENT surgeon performs surgical airway.

Post-Intubation:

• Secure tube meticulously (accidental extubation is catastrophic; re-intubation is extremely difficult).
• Take epiglottic swab and blood cultures.
• Transfer to Paediatric Intensive Care Unit (PICU).

3. Medical Management

Antibiotics (IV, High-Dose, Broad-Spectrum):

• First-Line:
  • Ceftriaxone 50-100 mg/kg/day IV (max 2g/dose) once daily, OR
  • Cefotaxime 150-200 mg/kg/day IV divided TDS (max 2g/dose).
• Rationale: Coverage for Hib, Group A Strep, Streptococcus pneumoniae, Staphylococcus aureus.
• If MRSA Suspected (local prevalence, previous colonisation): Add Vancomycin or Linezolid.
• Duration: 7-10 days total (can switch to oral once extubated and improving).

Corticosteroids:

• Dexamethasone 0.15-0.6 mg/kg IV (typical dose 0.4 mg/kg, max 10 mg).
• Evidence: Limited high-quality RCT evidence, but widespread use based on mechanism (reduce oedema) and observational data suggesting shorter intubation times.
• Timing: Administer early (once airway secured).

Fluid Resuscitation:

• Correct dehydration (patient has not swallowed fluids for hours).
• IV maintenance fluids (isotonic crystalloid).
• Caution: Avoid fluid overload (can worsen airway oedema).

Sedation and Analgesia (in PICU):

• Sedation: To tolerate intubation and prevent self-extubation. Options: midazolam infusion, propofol infusion.
• Analgesia: Morphine or fentanyl (for sore throat and ventilator synchrony).
• Muscle Relaxation: Generally avoided (prevents cough and airway protection), but may be needed in specific cases.

4. Intensive Care Management (PICU)

Ventilation:

• Mechanical ventilation, typically 24-72 hours.
• Mode: Pressure control or volume control (as appropriate for patient size and compliance).
• Minimize peak pressures to avoid barotrauma.

Monitoring:

• Continuous ECG, pulse oximetry, blood pressure.
• End-tidal CO₂ (ensures tube patency).
• Regular arterial blood gases (if arterial line placed).
• Hourly neurological observations (risk of concurrent meningitis).

Tube Security:

• Secure tube with ties and adhesive dressings.
• Sedation to prevent self-extubation.
• Daily chest X-ray to confirm tube position.

Cuff Leak Test (Before Extubation):

• Technique: Deflate the endotracheal tube cuff. Listen for air leak around the tube during positive pressure ventilation.
• Positive Leak (audible air leak): Indicates oedema has resolved; safe to extubate.
• No Leak (no air leak): Oedema persists; keep intubated for further 12-24 hours and re-test.
• Timing: Typically performed at 48-72 hours.

Extubation:

• Performed in controlled environment (PICU or theatre) with senior team present.
• Equipment for re-intubation immediately available.
• Post-extubation monitoring for stridor, respiratory distress.
• Nebulised adrenaline and dexamethasone on standby for post-extubation stridor.

5. Public Health Measures

Notification:

• Hib is a notifiable disease in the UK and most jurisdictions.
• Inform local Public Health team immediately.

Chemoprophylaxis for Contacts:

• Rifampicin Prophylaxis for household contacts if:
  • There are unvaccinated or incompletely vaccinated children less than 4 years in the household, OR
  • There is an immunocompromised individual in the household.
• Dose:
  • Children 1-12 years: 10 mg/kg once daily for 4 days.
  • Children >12 years and adults: 600 mg once daily for 4 days.
• Alternative: Ciprofloxacin (single dose) in adults.
• Note: Index case should also receive rifampicin before discharge (eradicates nasopharyngeal carriage).

Vaccination:

• Confirm and update Hib vaccination status of patient and household contacts.
• Catch-up vaccination for incompletely vaccinated individuals.

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8. Differential Diagnosis

Key Differentials (Upper Airway Obstruction in Children)

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9. Complications

Immediate Life-Threatening Complications

Complete Airway Obstruction

• Incidence: Can occur suddenly, precipitated by agitation, throat examination, or spontaneous progression.
• Presentation: Silent stridor, extreme distress, bradycardia, cyanosis, cardiovascular collapse.
• Management: Immediate bag-valve-mask ventilation (may be ineffective if total obstruction), emergency intubation or surgical airway.

Cardiorespiratory Arrest

• Mechanism: Hypoxia, hypercapnia, vagal stimulation (from airway manipulation).
• Prevention: Gentle, expert airway management; avoid agitation; maintain spontaneous ventilation until airway secured.

Airway-Related Complications

Accidental Extubation

• Risk: High in agitated, under-sedated patients.
• Consequence: Re-intubation is extremely difficult (persistent oedema). May require emergency surgical airway.
• Prevention: Secure tube meticulously, adequate sedation, close monitoring.

Post-Intubation Subglottic Stenosis

• Incidence: Rare (less than 1%) with modern cuffed tubes and careful management.
• Risk Factors: Prolonged intubation, traumatic intubation, oversized tube, tube movement, infection.
• Presentation: Stridor after extubation, persistent respiratory distress.
• Management: ENT assessment, may require bronchoscopy, laser therapy, or surgical resection.

Infectious Complications

Bacterial Meningitis

• Incidence: 10-15% of Hib epiglottitis cases (due to concurrent bacteraemia). [20]
• Presentation: Altered consciousness, seizures, neck stiffness, bulging fontanelle (infants).
• Investigation: Lumbar puncture (once airway and cardiovascular stability ensured).
• Management: IV antibiotics (ceftriaxone or cefotaxime already covers meningitis).

Pneumonia

• Incidence: Aspiration pneumonia (from pooled secretions) or haematogenous spread.
• Presentation: Hypoxia, crackles on auscultation, consolidation on chest X-ray.
• Management: Antibiotics (already administered), supportive ventilation.

Septicaemia and Septic Shock

• Incidence: More common with Hib and Group A Strep.
• Presentation: Hypotension, mottled skin, prolonged capillary refill time, lactic acidosis.
• Management: Fluid resuscitation, inotropic support, broad-spectrum antibiotics.

Other Invasive Hib Infections

• Septic Arthritis: Typically large joints (hip, knee).
• Pericarditis: Rare, life-threatening.
• Cellulitis: Facial or orbital cellulitis.

Anaesthetic and Intensive Care Complications

• Barotrauma: Pneumothorax, pneumomediastinum (from high airway pressures).
• Ventilator-Associated Pneumonia (VAP).
• Catheter-Related Bloodstream Infection.

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10. Prognosis and Outcomes

Survival and Recovery

Modern Mortality (less than 1%): With contemporary multidisciplinary management (early recognition, expert airway intervention, PICU care), mortality is less than 1% in developed healthcare systems. [10]

Historical Mortality (6-10%): Before the routine use of intubation and the establishment of PICU services, mortality was 6-10%. Most deaths occurred from airway obstruction or delayed diagnosis. [13]

Resolution of Swelling:

• Supraglottic oedema resolves rapidly with antibiotics and steroids.
• Extubation: Typically possible within 24-72 hours (median 48 hours).
• Complete Recovery: Most children return to normal baseline within 5-7 days of presentation.

Long-Term Outcomes

• Neurological Sequelae: Rare, but hypoxic brain injury can occur if airway obstruction leads to prolonged hypoxia or cardiac arrest.
• Subglottic Stenosis: Rare (less than 1%) with modern airway management.
• No Chronic Effects: Epiglottis returns to normal structure and function; no long-term voice or swallowing problems expected.

Recurrence

• Rare: Recurrence is extremely uncommon.
• Risk Factors: Immunocompromise, incomplete vaccination.

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11. Evidence and Guidelines

Key Guidelines

Landmark Studies and Systematic Reviews

1. Hib Vaccine Efficacy and Epidemiological Impact

• Heath PT, et al. (2000). Haemophilus influenzae type b conjugate vaccine: a review of efficacy data. Pediatr Infect Dis J. [18]
  • Key Finding: Hib conjugate vaccine efficacy >95%; incidence of invasive Hib disease (including epiglottitis) fell by >95% in vaccinated populations.
  • Implication: Hib vaccine is one of the most successful public health interventions; epiglottitis is now a disease of the unvaccinated or due to non-Hib pathogens.

2. Epidemiological Shift to Adults

• Baird SM, et al. (2018). Review of epiglottitis in the post Haemophilus influenzae type-b vaccine era. ANZ J Surg. [16]
  • Key Finding: In Australia (post-Hib vaccine), adult epiglottitis incidence stable or increasing; paediatric cases rare.
  • Implication: Clinicians must maintain vigilance for epiglottitis in adults presenting with severe odynophagia.

3. Airway Management Strategies

• Dowdy RAE, Cornelius BW (2020). Medical Management of Epiglottitis. Anesth Prog. [2]
  • Key Finding: Inhalational induction with spontaneous ventilation is safer than rapid sequence intubation with muscle relaxants in suspected epiglottitis.
  • Implication: Maintain spontaneous respiration until airway definitively secured.

4. Microbiology in the Post-Vaccine Era

• Shlomovich M, et al. (2025). Croup and Epiglottitis. Pediatr Rev. [3]
  • Key Finding: Group A Streptococcus, Streptococcus pneumoniae, and Staphylococcus aureus now dominate paediatric epiglottitis cases.
  • Implication: Empiric antibiotics must cover these organisms (ceftriaxone/cefotaxime appropriate).

5. Corticosteroid Use

• Limited RCT Evidence: No high-quality randomised controlled trials, but widespread use based on mechanistic rationale and retrospective cohort data suggesting reduced time to extubation.
  • Consensus: Dexamethasone 0.4 mg/kg IV is standard of care in most centres.

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12. Patient and Layperson Explanation

What is Acute Epiglottitis?

The epiglottis is a small, leaf-shaped flap of tissue that sits at the back of your child's throat, just above the windpipe (trachea). Its job is to close over the windpipe when your child swallows, preventing food and liquid from going into the lungs.

In acute epiglottitis, a germ (usually a bacteria) infects this flap, causing it to swell up very quickly—sometimes within just a few hours. The swollen epiglottis acts like a plug, blocking the windpipe and making it extremely hard for your child to breathe.

Why is this an emergency?

Because the windpipe can become completely blocked very suddenly, stopping all air from getting into the lungs. This can happen in minutes if something disturbs your child (like looking in their throat with a stick, or making them lie down). That's why we keep your child as calm and comfortable as possible, and take them straight to the operating room.

Why are you not checking my child's throat?

Looking into your child's throat with a tongue depressor or light could make them gag or cry. This sudden movement can cause the already swollen epiglottis to flop over and completely block the airway. It's safer to wait until your child is asleep with an anaesthetic in the operating room, where we have all the equipment ready to help them breathe if needed.

Why does my child have to sit up?

When your child sits leaning forward with their neck stretched out (like they're sniffing something), the airway is as open as it can be. If we lay them flat, gravity pulls the swollen tissue backwards and can block the windpipe. That's why we let them sit on your lap in the position they find most comfortable.

What will happen in the operating room?

A senior anaesthetist (a doctor who specialises in keeping patients safe during operations) will gently put your child to sleep using a gas to breathe (not an injection, as we don't want to upset them with a needle). Once they're deeply asleep, the doctor will put a small breathing tube down into the windpipe, past the swollen epiglottis. This secures the airway and keeps it open.

An ear, nose, and throat (ENT) surgeon will be in the room as well, ready to help if needed.

What happens after the breathing tube is in?

Your child will be taken to the Paediatric Intensive Care Unit (PICU), where they will stay on a ventilator (a machine that helps them breathe) for 1-3 days. We'll give them strong antibiotics through a drip to kill the infection, and medicine to reduce the swelling.

As the swelling goes down, we'll check that it's safe to remove the breathing tube. Most children can have the tube taken out after 2-3 days and go home a few days later.

Will my child be okay?

Yes. With modern treatment, more than 99 out of 100 children with epiglottitis recover completely with no lasting problems. The key is getting the breathing tube in quickly and safely, which is why we act so fast.

Can this happen again?

It's very rare for epiglottitis to come back. Once your child has recovered, they should be back to their normal self. We'll also check that they're up to date with their vaccinations to protect them in the future.

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13. Examination Focus

High-Yield Exam Topics (MRCPCH, MRCS, FRCA, PLAB, USMLE)

Written Exams (MCQ/SBA)

1. Classic Clinical Vignette

A 3-year-old child presents with sudden onset drooling, muffled voice, and high fever. He is sitting upright, leaning forward with his mouth open. Which is the MOST appropriate immediate action?

A. Examine the throat with a tongue depressor
B. Obtain a lateral neck X-ray
C. Insert an IV cannula and give IV antibiotics
D. Keep the child calm and call for senior anaesthetic and ENT help
E. Administer nebulised adrenaline

Answer: D. Do not disturb the child. Call for emergency airway team immediately. [4]

2. Imaging Sign

What radiological sign on lateral neck X-ray is characteristic of acute epiglottitis?

A. Steeple sign
B. Thumb sign
C. Air crescent sign
D. Hampton's hump
E. Sail sign

Answer: B. Thumb sign (swollen epiglottis). Steeple sign = croup (subglottic narrowing).

3. Microbiology

Which organism is the MOST common cause of epiglottitis in a fully vaccinated 4-year-old?

A. Haemophilus influenzae type b
B. Parainfluenza virus
C. Streptococcus pyogenes (Group A Strep)
D. Respiratory syncytial virus
E. Mycoplasma pneumoniae

Answer: C. Post-Hib vaccine, Group A Strep is now the leading cause. [3,7]

4. Antibiotic Choice

Which antibiotic is MOST appropriate for empiric treatment of acute epiglottitis?

A. Amoxicillin
B. Flucloxacillin
C. Ceftriaxone
D. Erythromycin
E. Metronidazole

Answer: C. Ceftriaxone (or cefotaxime) provides broad-spectrum cover for Hib, Group A Strep, pneumococcus, and Staph aureus. [2]

5. Public Health

Which household contacts of a child with confirmed Haemophilus influenzae type b epiglottitis require rifampicin prophylaxis?

A. All household members
B. Only unvaccinated or incompletely vaccinated children under 4 years
C. Only adults
D. No prophylaxis required
E. Only the index case

Answer: B. Rifampicin prophylaxis for unvaccinated/incompletely vaccinated children less than 4 years in the household. [18]

Clinical Exams (OSCE, Long Case, Short Case)

Station: Acute Paediatric Emergency

• Scenario: You are the paediatric registrar in the emergency department. A 4-year-old is brought in by ambulance with stridor and drooling.
• Task: Assess and manage.
• Key Actions (Examiner's Mark Scheme):
  • Recognise epiglottitis (tripod position, drooling, toxic, muffled voice, no cough).
  • Do NOT examine throat (state this explicitly to examiner).
  • Keep child calm, on parent's lap, sitting upright.
  • Call emergency 2222 (anaesthetist + ENT + senior paediatrician).
  • Transfer directly to theatre (do not delay for X-ray or bloods).
  • Explain plan to parents clearly and compassionately.

Station: Radiology Interpretation

• Image: Lateral neck X-ray showing thumb sign.
• Question: What is the diagnosis?
• Answer: Acute epiglottitis. Point out thumb sign (swollen epiglottis), obliterated vallecula.

Viva Voce (Oral Exam)

Examiner Question 1: "Talk me through the airway management of acute epiglottitis in a 3-year-old."

Model Answer: "Acute epiglottitis is a life-threatening airway emergency. The priority is to secure the airway without precipitating complete obstruction.

Pre-Theatre: I would keep the child calm, undisturbed, sitting upright on the parent's lap. I would not examine the throat, insert IV cannulas, or send the child for X-rays. I would call an emergency (2222) for a senior anaesthetist, ENT surgeon, and senior paediatrician, and transfer directly to theatre.

In Theatre: The anaesthetist would perform an inhalational induction with sevoflurane in 100% oxygen, maintaining spontaneous ventilation. We would avoid muscle relaxants until the airway is secured. The child would be gradually positioned supine as anaesthetic depth increases.

Direct or video laryngoscopy would be performed by the most experienced operator. I would expect to see a cherry-red, massively swollen epiglottis. We would use an endotracheal tube 0.5-1.0 mm smaller than predicted for age.

The ENT surgeon would be scrubbed and ready for a surgical airway (rigid bronchoscopy or emergency tracheostomy) if intubation fails.

Post-Intubation: The tube would be secured meticulously, and the child transferred to PICU for sedation, mechanical ventilation, IV ceftriaxone, IV dexamethasone, and fluids. We would perform a cuff leak test at 48-72 hours before extubation."

Examiner Question 2: "How do you differentiate croup from epiglottitis?"

Model Answer: "Viral croup and acute epiglottitis both present with stridor, but differ in key ways:

The critical point: if there is any suspicion of epiglottitis, treat as epiglottitis and secure the airway."

Examiner Question 3: "What is the 'cuff leak test' and why is it important?"

Model Answer: "The cuff leak test assesses whether supraglottic oedema has resolved sufficiently for safe extubation.

Technique: Once the child has been intubated and ventilated for 48-72 hours, I would deflate the cuff on the endotracheal tube and apply a positive pressure breath using the ventilator. I would listen for an audible air leak around the tube at the child's mouth or nose.

Interpretation:

• Positive leak (air leak heard): The oedema has subsided; there is space around the tube. Safe to proceed with extubation.
• No leak (no air leak): The airway is still tight; oedema persists. Extubation is high-risk. We would keep the child intubated for another 12-24 hours and repeat the test.

Importance: Premature extubation can lead to immediate re-obstruction and respiratory arrest. Re-intubation is extremely difficult due to persistent oedema and distorted anatomy. The cuff leak test is a simple, non-invasive predictor of safe extubation."

Examiner Question 4: "What are the complications of epiglottitis?"

Model Answer: "Complications can be categorised into immediate, airway-related, infectious, and long-term:

Immediate:

• Complete airway obstruction → cardiorespiratory arrest.

Airway-Related:

• Accidental extubation (difficult/impossible to re-intubate).
• Post-intubation subglottic stenosis (rare, less than 1%).
• Barotrauma (pneumothorax, pneumomediastinum).

Infectious:

• Bacterial meningitis (10-15% of Hib cases, due to concurrent bacteraemia).
• Pneumonia (aspiration or haematogenous).
• Septicaemia and septic shock.
• Other invasive Hib infections (septic arthritis, pericarditis).

Long-Term:

• Hypoxic brain injury (if arrest or prolonged hypoxia).
• Very rare in modern practice with prompt airway management."

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14. Cross-Specialty Pearls

For Emergency Medicine

• High Index of Suspicion: Any child with stridor + drooling + toxicity = epiglottitis until proven otherwise.
• Do Not Delay: Resist the urge to "complete the assessment" or "stabilise" the patient in ED. Transfer to theatre immediately.
• Heliox: Unlike in croup, Heliox (helium-oxygen mixture) is generally not helpful in epiglottitis and delays definitive management.

For Anaesthetics

• Spontaneous Ventilation is Key: Positive pressure ventilation with muscle relaxants can convert partial obstruction to complete obstruction.
• Video Laryngoscopy: Provides superior view and allows teaching/documentation, but requires experience.
• Prepare for Surgical Airway: ENT surgeon must be scrubbed, with tracheostomy set open on the table before induction.

For ENT Surgery

• Rigid Bronchoscopy as Plan B: Can bypass supraglottic obstruction and provide oxygenation if intubation fails.
• Surgical Airway (Plan C): Emergency cricothyroidotomy (older children) or tracheostomy (younger children). Front of Neck Access (FONA) training is essential.

For PICU

• Tube Security is Paramount: Accidental extubation is a "never event" in epiglottitis. Secure tube meticulously; sedate adequately.
• Beware Concurrent Meningitis: 10-15% of Hib epiglottitis has concurrent meningitis. Monitor neurology closely; consider lumbar puncture once stable.
• Cuff Leak Test Before Extubation: Do not extubate without confirming resolution of oedema.

For General Practice / Community Paediatrics

• Post-Discharge Vaccination: Ensure full Hib vaccination schedule completed. Notify public health for contact tracing and prophylaxis.
• Educate Parents: Very low risk of recurrence; full recovery expected. No long-term follow-up needed unless complications occurred.

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15. Summary: The "Epiglottitis Rule of 4's"

A mnemonic to remember the key features and management:

4 D's (Clinical Features):

1. Drooling
2. Dysphagia
3. Dysphonia (muffled voice)
4. Distress (air hunger)

4 "Do NOT's" (Management Principles):

1. Do NOT examine the throat
2. Do NOT force supine position
3. Do NOT delay for X-ray/bloods
4. Do NOT agitate the child

4 Key Team Members:

1. Senior Anaesthetist
2. Senior ENT Surgeon
3. Senior Paediatrician
4. PICU Team

4 Steps to Airway (Theatre):

1. Inhalational Induction (spontaneous ventilation)
2. Intubation (0.5-1.0 mm smaller tube)
3. Surgical Airway Ready (Plan B/C)
4. Secure and PICU (sedation, antibiotics, steroids)

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16. References

Primary Sources

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2. Dowdy RAE, Cornelius BW. Medical Management of Epiglottitis. Anesth Prog. 2020 Jun 1;67(2):90-97. doi: 10.2344/anpr-66-04-08. PMID: 32633776.

3. Shlomovich M, Hyatt S, Cassel-Choudhury GN. Croup and Epiglottitis. Pediatr Rev. 2025 Jul 1;46(7):364-377. doi: 10.1542/pir.2024-006420. PMID: 40588280.

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11. Difficult Airway Society (DAS). Paediatric Difficult Airway Guidelines. 2015. Available at: https://das.uk.com/guidelines/paediatric-difficult-airway-guidelines

12. Lazoritz S, Saunders BS, Bason WM. Management of acute epiglottitis. Crit Care Med. 1979 Jun;7(6):285-288. PMID: 446064.

13. Baxter JD, Pashley NR. Acute epiglottitis - 25 years' experience in management, The Montreal Children's Hospital. J Otolaryngol. 1977 Dec;6(6):473-479. PMID: 604513.

14. Pashley NR, Baxter JD. Acute epiglottitis in children - the morbidity of management by elective tracheostomy. J Otolaryngol. 1977 Dec;6(6):451-457. PMID: 604515.

15. del Carmen Otero M, Sanchís N, Modesto V, et al. [Acute epiglottitis caused by Haemophilus influenzae type b in children: presentation of 21 cases]. Enferm Infecc Microbiol Clin. 1997 Nov;15(9):461-465. PMID: 9527370.

16. Baird SM, Marsh PA, Padiglione A, et al. Review of epiglottitis in the post Haemophilus influenzae type-b vaccine era. ANZ J Surg. 2018 Nov;88(11):1135-1139. doi: 10.1111/ans.14787. PMID: 30207030.

17. Fondaw A, Arshad M, Batool S, et al. COVID-19 infection presenting with acute epiglottitis. J Surg Case Rep. 2020 Sep 4;2020(9):rjaa280. doi: 10.1093/jscr/rjaa280. PMID: 32922724.

18. Public Health England (PHE) / UK Health Security Agency (UKHSA). Immunisation Against Infectious Disease ("The Green Book"). Chapter 16: Haemophilus influenzae type b (Hib). Updated 2023. Available at: https://www.gov.uk/government/collections/immunisation-against-infectious-disease-the-green-book

19. Bedwell J, Zalzal G. Laryngomalacia. Semin Pediatr Surg. 2016 Jun;25(3):119-122. doi: 10.1053/j.sempedsurg.2016.02.004. PMID: 27301595.

20. Jones R, Santos JI, Overall JC Jr. Bacterial tracheitis. JAMA. 1979 Aug 24-31;242(8):721-726. PMID: 379379.

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Medical Disclaimer: MedVellum content is for educational purposes and clinical reference. Clinical decisions should account for individual patient circumstances. Always consult appropriate specialists and follow local protocols. In emergency situations, activate emergency services immediately.