emDOCs Podcast – Episode 64: Epiglottitis

Today on the emDOCs cast with Brit Long, MD (@long_brit), we cover epiglottitis.


Episode 64: Epiglottitis

 

Epidemiology:

  • Steadily increasing with an incidence of 1/100,000 to 4/100,000 in the U.S. in adults
  • Pediatric incidence has decreased to 0.5/100,000
    • Previously more common in unvaccinated children, but now more common in adults
  • Life-threatening infection of epiglottis
    • Occurs via direct invasion of the epithelial layer by the organism or by bacteremia
      • Bacteremia more commonly associated with pediatric epiglottitis, though does not correlate to the severity of infection
    • Edema and inflammatory cell accumulation in the potential space between the epiglottic cartilage and epithelial layer, resulting in swelling of the epiglottis and supraglottic structures
  • Often bacterial though can occur via viral or fungal infection, foreign body ingestion, thermal injury, lymphoproliferative disease or graft-versus-host disease, chronic granulomatous diseases, and caustic ingestions.

 

Microbiology:

  • Often polymicrobial, and predominant bacteria include:
    • Streptococcus pyogenes (group A strep), Staphylococcus aureus (MSSA, MRSA)
    • Pseudomonas aeruginosa should be considered in immunocompromised patients

 

Evaluation:

  • Adult and pediatric patients often differ in presentation.
  • Pediatric patients present more common with a sudden decompensation, evidence of respiratory distress/tripod position
  • Adult patients present with:
    • 90-100% with odynophagia
    • 85% with dysphagia
    • 74% with voice changes
    • Tripod positioning less common in adults due to larger airway caliber, occurring in less than 50% of adult patients
    • Voice change
    • Retractions
  • Rapid onset of symptoms within 12-24 hours is a harbinger of severe disease, though adults usually present in subacute fashion

 

Examination:

  • 90% of patients with epiglottitis with have a normal oropharyngeal exam
  • Fever in 26-90%
  • Muffled voiced in 50-65%
  • Difficulty handling secretions 50-80%
  • Cervical lymphadenopathy
  • Severe pain with palpation of the external larynx or hyoid bone
  • Direct visualization of the epiglottis with nebulized lidocaine
    • Clinician should face the patient and places the Macintosh blade onto patient’s tongue.
    • Ask patient to speak in a high-pitched tone, raising the supraglottic structures several centimeters for potential visualization

 

Laboratory analysis:

  • Limited utility since clinical diagnosis:
    • Cultures
      • Blood: 0-17% yield
      • Throat: 10-33% yield
      • Epiglottis: 75% yield
    • Dehydration due to odynophagia may be present, resulting in renal injury, electrolyte abnormalities

 

Imaging:

  • Upright lateral neck radiograph
    • Thumbprint sign: epiglottic swelling with a sensitivity of 89.2% and specificity of 92.2%
    • Vallecula sign: normal deep linear air space from the base of the tongue to the epiglottis is shallow or absent
    • Epiglottic width greater than 6.3 mm demonstrates has a sensitivity of 75.8% and a specificity of 97.8%.
    • False negative rate of 31.9% so negative radiograph does not rule out diagnosis
  • Computed Tomography (CT) with contrast of the neck
    • Requires patient to lay supine
      • May aggravate impending airway occlusion
    • Sensitivity of 88-100% and specificity of 97-96%
    • Can show:
      • Effusion
      • Obliteration of surrounding fat planes
      • Thickening of false vocal cords
      • Retropharyngeal enhancement and edema
      • Epiglottic abscess: Associated with a high likelihood of requiring airway
  •  Point of care ultrasound
    • Allows for evaluation in position of comfort
    • Increased anteroposterior diameter of the midpoint and lateral epiglottis associated with epiglottitis
    • Alphabet P sign is also suggestive of epiglottitis
      • hypoechogenicity on a longitudinal view at the thyrohyoid membrane level
    • Direct visualization of epiglottis confirms diagnosis—set up for therapeutic intervention simultaneously

 

Management:

  • Position of optimal patient comfort is key
  • Airway management
    • Intubation with flexible intubating endoscopy is the method of choice
    • Intubation occurs in epiglottitis patients in 13.2% of cases
    • Video laryngoscopy is used less commonly but is also an option
    • Do not use supraglottic devices; may not seat well and may cause airway occlusion
    • Factors associated with increased likelihood of intubation:
      • Historical factors: Diabetes mellitus, subjective dyspnea, rapid symptom progression over 12-24 hours, stridor,
      • Objective measures: 20 breaths per minute with subjective complaint of dyspnea required visualization of the airway, while a respiratory rate greater than 30 breaths per minute, hypercarbia (PCO2 greater than 45 mm Hg)
  •   Antibiotics:
    • Ceftriaxone 2g intravenous (IV) or ampicillin-sulbactam 3g IV with vancomycin 20 mg/kg IV for methicillin resistant Staphylococcus aureus (MRSA) coverage
    • Severe penicillin allergy: levofloxacin 750 mg IV
    • Immunocompromised: cefepime 2g IV is recommended for P. aeruginosa coverage
  • Corticosteroids are controversial though between 20-83% will receive corticosteroids
    • Have not demonstrated any improvement in ICU length of stay, hospital length of stay, or duration of intubation
  • Nebulized epinephrine may help temporize airway by assisting with bronchodilation
    • Do not use in children
      • Generates additional agitation, laryngospasm, and rapid deterioration with no benefit in the literature

 

Pearls:

  • More common in adults who present with odynophagia, dysphagia, and over a more subacute time frame
  • Normal oropharynx occurs in 90% of adults with epiglottitis
  • Lateral neck radiographs are a screening tool which may show the thumbprint or vallecula sign though have a high false positive rate
  • Factors associated with increased rates of intubation are diabetes mellitus, symptoms over 12-24 hours, stridor, drooling, tachypnea, hypercarbia, epiglottic abscess, and subglottic extension
  • Airway management has shifted from intubation/surgical airway in the operating room to awake fiberoptic intubation
  • Corticosteroids and nebulized epinephrine may assist in decompensating patients, but the literature is controversial

 

References:

  • Bridwell RE, Koyfman A, Long B. High risk and low prevalence diseases: Adult epiglottitis. Am J Emerg Med. 2022 Jul;57:14-20.

One thought on “emDOCs Podcast – Episode 64: Epiglottitis”

  1. Assuming this was just an oversight: For diagnosis/ visualization when direct viz is not successful an ED should invest in a diagnostic (as opposed to intubating) fiberoptic NPL scope. These are easy to use and generally well tolerated.
    It’s old school but I keep a dental mirror handy for diagnostic purposes, easy to use and sometimes your NPL is out of service for cleaning or repairs. (Used it last week, saved on imaging!)

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