Tracheal suction catheter

This device has never appeared in the CICM Fellowship exam as a written paper question (at least not since the year 2000). However, it is ubiquitous enought to merit some attention. Certainly, the NSW Health policy authors think so; they have dedicated a 43 page document to the art and science of tracheal suctioning.

Complications of tracheal suctioning

  • Tracheal ulceration
  • Haemoptysis
  • Hypoxia due to loss of PEEP
  • Sympathetic overactivity
  • Hypertension and increased intracranial pressure.
  • Vasovagal reflex
  • Laryngospasm (if suctioning from the nasopharyngeal airway)

Contraindications of tracheal suctioning

  •  unexplained haemoptysis
  • severe coagulopathies
  • severe bronchospasm
  • laryngeal stridor (if suctioning via the nasopharynx)
  • base-of-skull fracture (if suctioning via the nasopharynx)
  • haemodynamic instability (cough may cause worsening of venous return)

Specific recommendations made by the NSW Health policymakers:

  • Only suction when clinically indicated
  • Try to suction at least every 4 hours
  • Suction should only be applied for a maximum duration of 15 seconds
  • Suction should only be applied as the catheter is being withdrawn
  • The catheter itself should only occupy half of the internal diameter of the ETT, at maximum
  • Post-suctioning hypoxia should be minimised by preemptively irrigating the respiratory tract with several breaths of 100% FiO2
  • The old practice of "washing" the trachea with boluses of normal saline is actually harmful, and should not continue
  • Closed suction systems are preferred, and should be changed every 48 hours (i.e. systems which do not allow the escape of endotracheal gas or secretions during suctioning)


NSW Health Statewide Guidelines for Intensive Care. "Suctioning an Adult with a Tracheal Tube"