Acute Epiglottitis
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. Historically caused by Haemophilus influenzae type b (Hib), its incidence has plummeted in children due to vaccination, but it still occurs in unimmunised children and adults. Management is defined by a standard safety rule: Secure the Airway First. [1,2]
Key Facts
- The "Silent Killer": Unlike the loud barking cough of Croup, children with Epiglottitis are often quiet. They do not cough. They sit still to conserve air.
- Microbiology:
- Pre-vaccine: Hib (>90%).
- Post-vaccine: Group A Strep (Strep pyogenes), Strep pneumoniae, Staph aureus, or Non-typeable Haemophilus.
- Adults: Now more common in adults than children. Presents as severe sore throat (odynophagia) with a normal looking oropharynx.
Clinical Pearls
The "Hands Off" Rule: Never attempt to examine the throat with a tongue depressor or torch in a child with stridor + drooling. This can precipitate laryngospasm and immediate arrest. Keep the child calm, on the parent's lap, and do not cannulate or upset them until the airway team is ready.
Tripod Position: The child sits leaning forward, neck extended ("sniffing the morning air"), mouth open, tongue protruding. This maximises airway diameter. If you force them to lie down (e.g. for CT or exam), the airway will close.
Croup vs Epiglottitis: Croup: Viral prodrome, Barking cough, Hoarse voice, Low grade fever. Epiglottitis: Acute onset (hours), NO cough, Muffled voice, High fever (>38.5), Toxic, Drooling.
Demographics
- Children: Rare. Median age 2-5 years.
- Adults: Incidence stable/rising. Median age 40-50.
- Vaccination: Hib vaccine (at 8, 12, 16 weeks + booster at 1 year) is highly effective.
Mechanism
From bacterial colonization to obstruction takes only hours.
- Infection: Bacteremia seeds the supraglottic tissues.
- Inflammation: The loose mucosa of the epiglottis swells rapidly (Cellulitis).
- Obstruction: The "Cherry Red" swollen epiglottis curls posteriorly and inferiorly, acting like a ball-valve over the laryngeal inlet during inspiration.
The 4 D's
- Drooling: 80% of children. Pain prevents swallowing saliva.
- Dysphagia: Severe sore throat.
- Dysphonia: "Hot Potato" voice (muffled/soft), not hoarse.
- Distress: Anxiety, air hunger, inspiratory stridor.
Systemic
- General: Toxic child in tripod position.
- Oropharynx: DO NOT EXAMINE.
- Neck: May have tender lymphadenopathy.
- Lungs: Reduced air entry. Stridor.
First Line (ONLY if diagnosis unclear and patient stable)
- Lateral Soft Tissue Neck X-ray:
- Thumb Sign: Swollen epiglottis looks like a thumb (normal is a little finger).
- Vallecula Sign: Obliteration of the air pocket in the vallecula.
- Warning: Do not send an unstable child to X-ray. A doctor must accompany.
Gold Standard
- Direct Laryngoscopy: (In Theatre). Visualisation of the "Cherry Red" epiglottis confirm diagnosis and facilitates intubation.
- Blood Cultures: Positive in 50-90% (Hib).
- Epiglottic Swab: Take after intubation.
Management Algorithm
CHILD WITH STRIDOR + DROOLING
↓
DO NOT UPSET / DO NOT EXAMINE
(Keep on parent's lap, give oxygen
by wafting if tolerated)
↓
EMERGENCY CALL (2222)
(Anaesthetist + ENT Surgeon + Paediatrician)
↓
TRANSFER TO THEATRE
(Do not delay for X-ray or Bloods)
↓
INHALATIONAL INDUCTION (Gas)
(Sevoflurane while sitting up)
↓
INTUBATION (Video Laryngoscopy)
(ENT ready for Surgical Trachy/Cric)
↓
SECURE TUBE & ADMIT ICU
(IV Antibiotics + Steroids)
1. Airway (The Priority)
- Gas Induction: Spontaneous ventilation with Sevoflurane is safest. Muscle relaxants are dangerous (loss of airway tone).
- Tube: Use a tube 0.5-1.0mm smaller than usual (due to swelling).
- Plan B: If intubation fails, rigid bronchoscopy.
- Plan C: Emergency surgical airway (Front of Neck Access).
2. Medical
- Antibiotics: IV Ceftriaxone or Cefotaxime (High dose). Must cover Hib and Strep. Continue for 7-10 days.
- Steroids: IV Dexamethasone (0.15 - 0.6 mg/kg) to reduce oedema.
- Fluids: Correct dehydration (patient hasn't swallowed for hours).
3. Public Health
- Notification: Hib is a notifiable disease.
- Prophylaxis: Rifampicin for household contacts (if unvaccinated children present).
- Sudden Airway Death.
- Meningitis: Occurs in concurrent Hib infection.
- Pneumonia.
- Accidental Extubation: Re-intubation is extremely difficult.
- Survival: >99% if airway secured promptly.
- Resolution: Swelling subsides rapidly (24-48 hours). Extubation usually possible within 2-3 days (check for "cuff leak" first).
Key Guidelines
| Guideline | Organisation | Key Recommendations |
|---|---|---|
| The Child with Stridor | APLS / BTS | Difficult Airway algorithm. "Heliox" generally not useful here. |
| Airway Management | DAS (Difficult Airway Society) | Paediatric difficult airway guidelines. FONA drill. |
Landmark Trials
1. Hib Vaccine Efficacy
- Introduction of the conjugate vaccine reduced incidence by >90% worldwide. Most cases now are vaccine failures or unimmunised immigrants.
What is Epiglottitis?
The epiglottis is a small flap of tissue at the back of the throat that prevents food from going down the windpipe when we swallow. In this condition, a germ infects this flap, making it swell up massively - like a stepped-on grape.
Why is it an emergency?
Because the flap sits right on top of the windpipe, if it swells too much, it can completely block the air from getting into the lungs.
Why are you not checking his throat?
If we put a stick or light in his mouth, he might gag or cry. This triggers a reflex that can snap the swollen flap shut, blocking his breathing instantly. We must wait until he is safely asleep in the operating room.
Will he be okay?
Yes, once the breathing tube is in, he is safe. The antibiotics work very fast, and usually, the tube can come out in a couple of days.
Primary Sources
- Advanced Paediatric Life Support (APLS). The Practical Approach. 6th Edition. 2016.
- Glynn F, et al. Acute epiglottitis: management in the current era. J Laryngol Otol. 2008.
- Difficult Airway Society (DAS). Paediatric Difficult Airway Guidelines. 2012.
Common Exam Questions
- Imaging: "Sign on lateral neck X-ray?"
- Answer: Thumb Sign.
- Management: "First step in unstable child?"
- Answer: Call Anaesthetist/ENT. (Do not cannulate/examine).
- Prophylaxis: "Drug for household contacts of Hib?"
- Answer: Rifampicin.
- Differential: "Barking cough vs Silent drooling?"
- Answer: Croup vs Epiglottitis.
Viva Points
- Adult Epiglottitis: Often missed because we think it's a "child's disease". Suspect it in any adult with "The worst sore throat of my life" but a normal looking throat. They often do not need intubation (larger airway) but need close observation in HDU/ICU.
- The "Cuff Leak" Test: Before extubating, deflate the cuff. If you can hear air leaking around the tube, the swelling has gone down. If no leak, the airway is still tight; keep them intubated.
Medical Disclaimer: MedVellum content is for educational purposes and clinical reference. Clinical decisions should account for individual patient circumstances. Always consult appropriate specialists.