Respiratory Failure

Respiratory failure occurs when the breathing system fails to keep adequate blood oxygen levels. There may also be difficulties in removing waste gases, mainly blood carbon dioxide.

What causes it?

Every time we take a breath in we are taking oxygen from the air down to the lungs which then crosses over into the blood and is then transported to the various organs. At the same time carbon dioxide, which is the waste gas produced by organs, crosses from the blood and into the lungs - we then breathe this out. This whole process requires an interplay of various systems such as the lungs, the heart, the chest muscles and the brain. When any of these are impaired we are at risk of respiratory failure. Respiratory failure is defined by low blood oxygen levels and there may also be raised blood carbon dioxide levels.

There are various causes of respiratory failure, the most common being due to the lungs or heart. The lung disorders that lead to respiratory failure include chronic obstructive pulmonary disease (COPD), asthma and pneumonia. Heart disease that can lead to respiratory failure can be heart failure which may or may not be accompanied by a heart attack.

Read more about the causes of respiratory failure.

What do I feel when it happens?

Very early on there may not be any symptoms or just tiredness after exertion. Gradually, as the respiratory failure worsens, there is an inability to get oxygen to the body's organs. The most common features are shortness of breath (which may be at rest or on exertion) and becoming tired easily. There may also be symptoms of the underlying causes, such as a raised temperature in pneumonia or leg swelling in heart failure.

Learn about the symptoms of respiratory failure.

Do I need any further tests?

People with sudden respiratory failure or new respiratory failure are likely to need urgent hospital admission. Further tests will be required to make the diagnosis and to find the underlying cause. These tests are likely to include blood tests, a chest X-ray, a heart ultrasound scan (echocardiography) and a computerised tomography (CT) scan of the lungs.

Discover more about the diagnosis of respiratory failure.

How is it treated?

Treatment of sudden or new respiratory failure often requires emergency measures to make the patient more stable medically. This may require resuscitation and artificial ventilation. Patients may need to be admitted to the intensive care unit or the high dependency unit (based on how unwell the patient is).

Treatment will aim to improve the blood oxygen levels and remove the waste gas carbon dioxide if it is raised. This will usually require artificial ventilation. Further treatment will be aimed towards the underlying cause, such as antibiotics in pneumonia or diuretics in heart failure.

Some patients may become worse despite treatment and they may not survive. If someone can no longer be treated with a view to cure, but still needs symptom control, they may be referred to the palliative care team in hospital or to the Macmillan nurses in the community.

Read more about the treatment of respiratory failure.

Does it lead to any complications?

Respiratory failure is a serious illness and it may take many days to weeks for the patient to get better. Complications can occur at any stage of the illness and can affect a number of the body's organs. For example, severe lung illness can make a blood clot in the lung more likely. Artificial ventilation can lead to irreversible scarring of the lungs which can make respiratory function worse.

Not smoking and stopping smoking are important to preserve healthy lungs.

Learn about the complications of respiratory failure.

Did you find this information useful?

Thanks for your feedback!

Why not subcribe to the newsletter?

We would love to hear your feedback!

Dr Gurvinder Rull
Peer Reviewer:
Prof Cathy Jackson
Document ID:
29398 (v1)
Last Checked:
06 July 2017
Next Review:
05 July 2020

Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. Patient Platform Limited has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.