Acute Epiglottitis
Definition And Epidemiology
- Inflammation involves epiglottis and adjacent supraglottic structures.
- Progresses rapidly to life-threatening airway obstruction without prompt treatment.
- Annual incidence decreased significantly post-vaccine implementation.
- Current incidence rests at two cases per 10 million populations.
- Prevalence shifted from preschool demographic to school-age children and adolescents.
Etiology
- Primarily infectious origin.
- Accidental ingestion of hot liquid can also cause supraglottic injury mimicking epiglottitis.
| Status | Bacterial Pathogens | Other Pathogens |
|---|---|---|
| Immunocompetent | Haemophilus influenzae type b (unvaccinated/incompletely immunized) | Influenza Type A And B |
| Staphylococcus aureus | Parainfluenza Virus | |
| Streptococcus pneumoniae | Herpes Simplex Virus | |
| Streptococcus pyogenes | Epstein-Barr Virus | |
| Neisseria meningitidis | Human Immunodeficiency Virus | |
| Pasteurella multocida | Severe Acute Respiratory Syndrome Coronavirus 2 | |
| Immunocompromised | Pseudomonas aeruginosa | Fungal Agents |
Pathogenesis And Pathophysiology
- Inflammatory edema accumulates in potential space between loosely attached squamous epithelial layer and epiglottal cartilage.
- Swelling progresses with extreme rapidity.
- Reduced upper airway caliber causes turbulent airflow.
- Posterior and inferior curling of epiglottis creates ball-valve obstruction mechanism.
Clinical Features
Young Children
- Acute, rapidly progressive, potentially fulminating course.
- High fever, sore throat, severe dyspnea.
- Toxic appearance within hours.
- Marked dysphagia, labored breathing.
- Drooling heavily present.
- Stridor indicates near-complete airway obstruction.
- Barking cough characteristically absent.
- Classic tripod or sniffing posture adopted.
- Patient sits upright, leans forward, chin thrust forward, neck hyperextended, mouth open.
- Extreme reluctance to lie flat.
- Brief air hunger and restlessness precede rapidly increasing cyanosis and coma.
Older Children And Adolescents
- Low-grade fever accompanies progressively painful sore throat.
- Severe sore throat out of proportion to oropharyngeal examination findings.
- Severe dysphagia and drooling manifest.
- Minimal respiratory distress initially.
Differential Diagnosis
- Distinguishing acute upper airway obstruction etiologies remains critical.
| Feature | Acute Epiglottitis | Viral Croup | Bacterial Tracheitis | Retropharyngeal Abscess |
|---|---|---|---|---|
| Age | 3β14 Years | 6 Months To 3 Years | 6 Months To 14 Years | 2β4 Years |
| Onset Speed | Very Rapid (Hours) | Gradual | Rapid | Gradual |
| Appearance | Toxic | Non-Toxic | Toxic | Toxic |
| Fever | High Grade | Low Grade | High Grade | High Grade |
| Cough | Absent | Barking | Barking, Painful, Productive | Absent |
| Sore Throat | Present | Absent | Absent | Present |
| Dysphagia/Drooling | Present | Absent | Absent | Present |
| Voice Quality | Muffled | Hoarse | Very Hoarse | Muffled |
| Neck Pain/Stiffness | Absent | Absent | Absent | Present |
| Tracheal Tenderness | Absent | Absent | Present | Absent |
| Preferred Position | Tripod, Extended Neck | No Preference | Supine | No Preference |
| Lateral Neck Radiograph | Thumb Sign | Normal | Subglottic Haziness | Enlarged Prevertebral Space |
| Adrenaline Response | None | Very Good | Minimal/None | None |
Diagnostic Evaluation
Airway Precautions
- Avoid invasive procedures prior to securing airway.
- Withhold phlebotomy, intravenous line placement, or frightening interventions.
- Forbid direct examination of oral cavity, pharynx, or larynx.
- Agitation induced by pain worsens respiratory distress, precipitating sudden respiratory arrest.
Direct Visualization
- Confirms diagnosis via direct laryngoscopy.
- Reveals large, cherry red, swollen epiglottis.
- Perform exclusively in controlled settings (Operating Room, Intensive Care Unit).
- Require presence of airway experts (Anesthesiologist, Otolaryngologist).
Imaging
- Soft-tissue lateral neck radiograph supports diagnosis if presentation remains atypical.
- Reveals "Thumb Sign" representing enlarged epiglottis protruding from anterior hypopharyngeal wall.
- Shows thickened aryepiglottic folds.
- Demonstrates loss of vallecular air space.
- Displays distended hypopharynx.
- Ensure proper patient positioning with adequate hyperextension.
- Never delay definitive airway management for imaging.
Laboratory Studies
- Perform solely after airway stabilization.
- Complete Blood Count shows elevated white blood cell count (non-specific finding).
- Blood and epiglottic surface cultures yield variable results.
- Concomitant bacteremia frequently present.
Management
Airway Control
- Constitutes absolute mainstay of treatment.
- Immediate endotracheal intubation, nasotracheal intubation, or tracheostomy indicated regardless of apparent distress level.
- Select tube size 0.5 To 1.0 Millimeters smaller than standard age/height estimation.
- Provide supplemental oxygen continuously in non-threatening manner.
- Keep emergency surgical airway equipment readily available.
- Extubation planned after 2 To 3 days following antimicrobial therapy initiation.
- Confirm resolution of epiglottic swelling via fiberoptic laryngoscopy prior to extubation.
Pharmacotherapy
- Administer appropriate antimicrobials immediately post-airway stabilization.
- Ceftriaxone 50-100 mg/kg/day Intravenous or Intramuscular once/twice daily.
- Alternatively, Cefotaxime 50 mg/kg/dose q8H.
- Add Vancomycin 15 mg/kg/day q8H if Staphylococcus aureus suspected.
- Continue antibiotics for 7 To 10 days.
- Avoid Corticosteroids; unproven benefit.
- Avoid Bronchodilators and Racemic Epinephrine; strictly ineffective.
Complications And Prognosis
- Mortality rate reaches 6 Percent without artificial airway.
- Mortality falls below 1 Percent following successful airway securement.
- Fatal outcomes stem directly from complete laryngeal obstruction.
- Concomitant infections include pneumonia, cervical adenopathy, and otitis media.
- Meningitis and septic arthritis rarely occur alongside Haemophilus influenzae type b infections.
- Pulmonary edema may associate with acute airway obstruction.
Prevention And Chemoprophylaxis
- Maintain strict adherence to Haemophilus influenzae type b immunization schedules.
- Initiate chemoprophylaxis swiftly for close contacts if vulnerable individuals reside in household.
- Vulnerable contacts include infants below 12 months, incompletely vaccinated children below 4 years, and immunocompromised patients.
- First-line prophylaxis: Rifampicin 20 Milligrams/Kilogram (Maximum 600 Milligrams) once daily for 4 days.
- Rifampicin for infants below 3 months: 10 Milligrams/Kilogram once daily for 4 days.
- Alternative options include Ceftriaxone Intravenous/Intramuscular for 2 days or Azithromycin once daily for 3 days.