Complications of
Endotracheal Tubes

 

• Radiographs are obtained routinely after intubation
  • Endotracheal tube (ETT) is recognized by thin white opaque line usually running the length of the tube
• Position of carina
  • Follow right or left main stem bronchus backwards until it meets opposite main stem bronchus
  • Projects over T5, T6 or T7 in 95% of cases
• Movement of tip with flexion and extension
  • Neck flexion may cause 2 cm of descent of tip of tube
  • Neck extension from neutral may cause 2 cm of ascent of tip
• With head in neutral position (i.e., bottom of mandible is over C5-C6), tip of ETT should be 5-7 cm from carina
  • About half the distance between the medical ends of clavicles and carina
• Ideally tube should be ½ to 2/3 width of trachea
  • Cuff should fill, but not bulge, the lumen of the trachea
• Malpositions of the tube
  • Occurs about 15% of all intubations with emergency intubation having highest rate
  • Intubation of the esophagus can be recognized by marked gastric distension
  • Tip of tube too deep
    • About 10% of ETT are initially placed in the right main stem bronchus
    • With time, the left lung becomes atelectatic
      • If on ventilator, the right lung may be hyperinflated
        • May lead to pneumothorax or tension pneumothorax
    • If tip is in bronchus intermedius, RUL will also become atelectatic along with all of left lung

Tip of endotracheal tube (red arrow) projects below the carina
(blue arrow) into the bronchus intermedius on the right.
Click here to same image without arrows

• Tip of tube too shallow
  • Tip should be at least 3 cm distal to cords
  • Edema of the nasal mucosa by an ETT may cause sinusitis
  • Tube in pharynx may cause gastric dilatation
  • Aspiration of gastric contents
  • Cuff inflated between the vocal cords may produce glottic edema which may progress to scarring

• Perforation of the pharynx or trachea by an ETT are uncommon
  • Think of it if pneumomediastinum or subcutaneous emphysema develop after a difficult intubation
  • Usually perforation occurs in the posterior pharyngeal wall or piriform sinuses
  • Inflation of cuff greater than 2.8cm should make one think of tracheal laceration
• Teeth, fillings or dentures may be dislodged at the time of intubation
• Atelectasis is the single most frequent cause of airspace disease in an intubated patient
• Long-term complications
  • Tracheal stenosis at tube tip or site of inflated cuff

  

Goodman, L and Putman, C:  Intensive Care Radiology: Imaging of the Critically Ill W.B. Saunders, 1983

 McCloud T: Thoracic Radiology: The Requisites Mosby, 1998.