Ventilation and Weaning

Original Editor - The Open Physio Project

Top Contributors - Evan Thomas, Fasuba Ayobami, Rachael Lowe and Karen Wilson


Ventilation can be defined as the process of exchange of air between the lungs and the ambient air[1]. In the clinical setting, a machine known as a mechanical ventilator is used to perform this function on patients faced with serious respiratory illness. Weaning is the gradual withdrawal of a patient from dependency on a life-support system or other form of therapy[2]. Weaning a patient from a ventilator occurs when the condition of the patient improves and a decision is made to remove them from the ventilator through a trial of spontaneous breathing through the endotracheal tube and eventually extubation (removal of the tube).


The procedure is as follows:

  • Explanation of the procedure to the patient, assuring them it is only for a trial period
  • The ventilator support is gradually reduced (e.g. reducing pressure during pressure support)
  • The patient is placed into a better postural position (e.g. sitting upright or half-sitting)
  • The airway is suctioned
  • The patient is disconnected from the ventilator and given oxygen or mechanical assistance (CPAP)
  • The patient is encouraged to breathe spontaneously
  • The patient is monitored for signs of laboured breathing, anxiety or an increase in PaCO2
  • Extubation should occur as soon as possible because breathing through an endotracheal tube increases the work of breathing
  • Encourage the patient to cough after being extubated

Patients may be extubated when they are alert, show a stable breathing pattern and control their airway. Difficulties in weaning patients from a ventilator can occur due to:

  • Inspiratory muscle atrophy
  • Fatigue
  • Paralysis of the diaphragm
  • A fear of suffocating


The following are links to documents that serves as clinical guidelines to the use of mechanical ventilator and when to commence weaning process;



  1. Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. (2003). Retrieved September 26 2017 from
  2. Farlex Partner Medical Dictionary. (2012). Retrieved September 26 2017 from