The difficult airway

Predicting the difficult airway

ASA Difficult Airway Algorithm

• Does not necessary apply to the ED since the patient can always be awakened and case cancelled
  • Cricothyrotomy should always be the last step in patients with failure to oxygen and ventilate with BVM and inability to intubate
  • Straight blade- Miller- may offer better manipulation of a large epiglottis in children or for micrognathia or "buck teeth"

Improving Passive Oxygenation

See Apneic oxygenation

Intubation Options

Intubation Type	Pros	Cons
Traditional
Awake intubation
Nasal intubation		Lower success rate *Higher complication rate (e.g. bleeding, emesis, and airway trauma) Do not attempt in patients with posterior pharyngeal swelling such as in Angioedema (Upper Airway)
Retrograde intubation		Need time to set up *Risk hematoma, pneumothorax
Fiberoptic bronchoscopic intubation		Takes time to set up *Limited by secretions, bleeding, poor suction,

Surgical Airways

• Surgical cricothyrotomy
• Needle cricothyrotomy
• Pediatric jet ventilation

Special Situations

Severe Metabolic Acidosis

Further drop in pH during intubation can be catastrophic

• NIV (SIMV Vt 550, FiO2 100%, Flow Rate 30 LPM, PSV 5-10, PEEP 5, RR 0)
  • SIMV on ventilator, not NIV machine
  • "Pseudo-SIMV" mode
• Attach end-tidal CO2 and observe value
• Push RSI medications
• Turn the respiratory rate to 12
• Perform jaw thrust
• Wait 45sec
• Intubate
• Re-attach the ventilator
• Immediately increase rate to 30
• Change Vt to 8cc/kg
• Change flow rate to 60 LPM (normal setting)
• Make sure end-tidal CO2 is at least as low as before

Active GI Bleed

1. Empty the stomach
   • Place an NG and suction out blood
     • Varices are not a contraindication
   • Metoclopramide 10mg IV
     • Increases LES tone
2. Intubate with HOB at 45°
3. Preoxygenate!
   • Want to avoid bagging if possible
4. Intubation meds
   • Use sedative that is BP stable (etomidate, ketamine)
   • Use paralytics (actually increases LES tone)
5. If need to bag:
   • Bag gently and slowly (10BPM)
   • Consider placing LMA
6. If patient vomits
   • Place in Trendelenberg
   • Place LMA
   • Use meconium aspirator
7. If patient aspirates anticipate a sepsis-like syndrome
   • May need pressors, additional fluid (not antibiotic!)

See Also

Airway Pages

• Pre-intubation
  • Predicting the difficult airway
  • Bag valve mask ventilation
    • Oropharyngeal airway
    • Supraglottic airway
  • Apneic oxygenation
    • EBQ:ED Preoxygenation
• Induction
  • Critical care quick reference
  • Rapid sequence intubation
  • Delayed sequence intubation
• Intubation
  • Intubation (peds)
  • Direct laryngoscopy
  • Video Laryngoscopy
  • Bougie
  • The difficult airway
  • Advanced airway adjuncts
    • Supraglottic airway
  • Non-traditional intubation
    • Awake intubation
    • Nasal intubation
    • Blind digital intubation
• Surgical airways
  • Surgical cricothyrotomy
  • Needle cricothyrotomy
  • Pediatric jet ventilation
• Post-intubation
  • Mechanical ventilation (main)
  • Deterioration after intubation (DOPE)

Mechanical Ventilation Pages

• Noninvasive ventilation
• Intubation
  • Intubation (peds)
• Mechanical ventilation (main)
  • Ventilation modes
  • Initial mechanical ventilation settings
    • Initial mechanical ventilation settings (peds)
  • Adjusting mechanical ventilation settings
    • Deterioration after intubation
    • Lung recruitment maneuver
    • Ventilator high pressures
    • Ventilator associated lung injury
  • Weaning mechanical ventilation
    • Extubation
• Miscellaneous
  • ARDS and EBQ:ARDSnet
  • Airway pressure release ventilation
  • Ideal Body Weight Estimation

Video

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