Mechanical Ventilation
Date last updated: Dec 04, 2022
This article is coming soon and will provide an overview of mechanical ventilation including a discussion of devices types, modes, indications for use, as well as strategies and tools for ventilator management.
Ventilator terminology
Ventilator equipment & accessories
Indications for mechanical ventilation
Ventilator Modes
Lung protective ventilation
Liberation from invasive mechanical ventilation
Ventilator Liberation
- Protocolized ventilator weaning and timely liberation from mechanical ventilation can help improve outcomes for patients and conserve intensive care resources
- Intubated patients should be assessed daily for readiness for extubation
- There are multiple strategies for readiness testing and weaning prior to extubation
- Patients who are requiring <50% FiO2, <10 PEEP, are improving, and are hemodynamically stable likely qualify for a spontaneous breathing trial (SBT)
Spontaneous breathing trials
The use of a daily spontaneous awakening trial (SAT) coordinated with a spontaneous breathing trial (SBT) protocol can help extubate patients faster and improve patient outcomes (See figures below). If a patients fails an SBT, the cause should be identified, addressed and the SBT should be attempted again once deemed appropriate. If a patient passes the SBT, then extubation should be considered if other criteria for extubation are met, including ability to protect the airway and clear secretions.
Job aid for ventilator weaning, cuff leak and respiratory care by OCC. As featured in the WHO SARI Toolkit 2022. CC SA BY NC
Cuff leak test
All patients must be monitored for signs of respiratory failure after extubations. There are multiple potential reasons for post extubation failure, including post extubation stridor. Post extubation stridor has been associated with multiple risk factors including:
- Prolonged intubation
- Prone positioning
- Airway or neck trauma
- Volume overload
For patients with these risk factors or other concerns, a cuff leak test should be considered (See figure below). A cuff leak test may help to determine that the airway is likely to be patent after extubation, i.e. without swelling. When an adequate cuff leak is present, it signifies that the patient’s airway is unlikely to be profoundly edematous, and the patient is less likely to have post-extubation stridor (PES).
Data on the predictive value of cuff leak tests vary, and generally the cuff leak test has higher specificity than sensitivity. The presence of a cuff leak does not ensure a patient’s airway will remain open after extubation. When an adequate cuff leak is not present, consider steroids, elevating the head of the bed to reduce swelling, or direct laryngoscopy to further evaluate; consider repeating the test again in 12–24 hours.