Direct laryngoscopy

Overview

  • Used to facilitate intubation
  • Provides direct line of sight of vocal cords (as opposed to video laryngoscopy)
  • Most often utilizes Mac or Miller Blade
  • Miller blade more popular in pediatric intubation because of floppy epiglottis (most common in those <2 years of age)

Indications

Contraindications

Equipment Needed

  • Handle with light source
  • Macintosh or Miller Blade
  • A Macintosh 3 blade or Miller 2 blade are appropriate for most adults
Macintosh Blades 1-5, from bottom to top

Procedure (Macintosh Blade)

  1. Place patient into sniffing position
  2. Use "scissor" technique with right hand to open mouth
  3. Insert laryngoscope blade into right side of mouth
  4. Slowly advance blade into mouth while performing "tongue sweep"
  5. Identify epiglottis
  6. Advance tip of blade into vallecula
  7. Lift upward and away from operator to expose glottis

Procedure (Miller Blade)

  1. Place patient into sniffing position
  2. Use "scissor" technique with right hand to open mouth
  3. Insert laryngoscope blade into right side of mouth
  4. Slowly advance blade into mouth while performing "tongue sweep"
  5. Identify epiglottis and gently lift with tip of blade
  6. Lift upward and away from operator to expose glottis


  • An alternative technique if initially unsuccessful is to purposefully insert the blade into the esophagus and withdrawal until the glottis is visualized

Optimizing Laryngoscopy

  • Ensure patient is in sniffing position
    • Extension of cervical spine
    • Flexion of atlanto-occipital joint
  • Bimanual laryngoscopy
    • Have assistant place hand over trachea
    • Use right hand to apply pressure over assistants hand and manipulate trachea until cords are visualized
    • Have assistant maintain position as you deliver tube
  • If epiglottis is "floppy" (common in peds), retract blade slightly and lift epiglottis with blade (similar to how Miller blade is used)
  • Can use right hand to lift patients head off bed, when view obtained, have assistant place fist under patient head and use right hand to deliver tube

Complications

  • Dental Trauma (minimize risk while lifting blade upward and away from operator)
  • Laryngeal Trauma (risk increased with multiple attempts)
  • Sympathetic nervous system stimulation leading to tachycardia and hypertension

See Also

Airway Pages

External Links

References

  1. Peterson K, Ginglen JG, Valenzuela FI, et al. Direct Laryngoscopy. [Updated 2020 Mar 31]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK513224/[Category:Procedures]]