Mechanical Ventilation- Why do we do it? Goals and Indications

Mechanical ventilation is a supportive process in that we are aiming to treat the underlying cause of the patients problem whilst we support their lung function. Hopefully once the underlying problem is solved we can then take the patient off the ventilator.

Very basically then;


Normalise arterial blood gas:

  • Normalise acid base balance
  • Normalise ventilation
  • Normalise oxygenation.

Remove or reduce the patients work of breathing by unloading the respiratory muscles. We need to aim to do this in a synchronised manner.


Type I Respiratory failure- Hypoxeamic failure.

  • Low oxygen status for example caused by:
    • Congestive heart failure
    • ARDS
    • Pulmonary embolism

Type II Respiratory failure- Hypercapnic failure.

  • High carbon dioxide for example caused by:
    • Chronic obstructive airways disease
    • Drugs
    • Neuromuscular disease.

Airway Protection

  • Airway swelling
  • Surgery
  • Trauma

Please go to Ollie Pooles fabulous YouTube resource for the learning this post was based on….

Guidelines for the management of tracheal intubation in critically ill adults

Having read the guidelines I made these infographics. They are FREE. Just let me know your email address and they will be sent to you.