Surgical Principles: Endotracheal Intubation

Direct Laryngoscopy

• Use of a Laryngoscope to Directly Visualize the Vocal Cords for Endotracheal Intubation
• Levitan Approach:
  • Position & Preparation
  • Visualize the Epiglottis
  • Laryngeal Exposure
  • Place the Tube
• Average Endotracheal Tube (ETT) Size
  • Adult Females: 7.5 mm
  • Adult Males: 8.5 mm
• Best Determinant of Esophageal vs Tracheal Intubation: End Tidal CO2
  • Better Than Direct Visualization
  • Transtracheal US Can Supplement Patients in Cardiopulmonary Arrest – May Have Decreased Flow & Falsely Low ETCO2
• Goal Distance: Tip 2-3 cm Above Carina

Laryngoscope Blades

• Macintosh (Most Common)
  • Curved Blade with 90-Degree Handle
  • Tip is Placed in Vallecula (Between Tongue & Epiglottis)
• Miller
  • Straight Blade with Curved Tip
  • Tip is Placed Under Epiglottis
• Other Less Commonly Used:
  • Kessel – Curved with 110-Degree Handle
  • McCoy – Curved with a Flexible Distal Tip

Rapid Sequence Intubation (RSI)

• *See Surgical Principles: Rapid Sequence Intubation (RSI)

Rescue Techniques

• Cricoid Pressure (Sellick Maneuver)
  • External Digital Pressure Applied to the Cricoid Cartilage
  • Prevents Passive Regurgitation of Gastric Contents (No Real Evidence)
  • Generally Does Not Assist is Visualization
    • May Actually Inhibit View & Compress the Airway Blocking Tube Passage
• Video Laryngoscopy
  • Fiberoptic Videoscopic Guidance to Allow Better Visualization
  • Some Consider it to be “Standard of Care” – Heatedly Debated
  • Examples: GlideScope, Storz C-Mac, etc.
• Flexible Bougies
  • Bent Thin Semi-Rigid Stylette that is Easier to Place than the Larger Tubes
  • Placement:
    • Bougie is First Placed Through Cords into Trachea
    • Produces “Washboard Effect” as it Rubs Against Tracheal Rings to Confirm Placement
    • Endotracheal Tube Then Advanced Over the Bougie into Place
• Laryngeal Mask Airway (LMA)
  • Elliptical Cuff, Tip Occludes Esophagus
  • Creates Low Pressure Seal Around Larynx
  • Not a Definitive Airway Protection & Does Not Ensure Patency
• Combitube
  • Dual Lumen Esophagotracheal Tube
    • One Tube in Esophagus
    • One Tube in Trachea
• Emergency Cricothyroidotomy

Pediatric Considerations

• Use Uncuffed Tubes in Neonates < 1 Year Old
  • OK to Use Cuffed Tubes in Older Peds
  • *Old Dogma: Do Not to Use Cuffed Tubes in Peds, Now OK Given Newer Tubes with Lower Pressure
• Tube Size Approximation:
  • Size = Age/4 + 4
  • Can Use Patient Pinky to Estimate Tube Diameter
• Cricothyroidotomy Contraindicated Under Age 10-12
  • *See Trauma: Emergency Surgical Airway
• Short Trachea Makes it Easier to Mainstem

Ventilator Management

• *See Surgical Critical Care