Intracranial Pressure Monitoring

Intracranial pressure (ICP) monitoring is used to check the pressure inside the skull of a person who has had brain injury. Injuries such as bleeding, trauma or surgery can cause the brain to swell. If the swelling develops, the pressure inside the rigid skull rises, which may harm the brain. To measure the pressure inside the skull, a special probe may be inserted into a ventricle (space) of the brain or into brain tissue.

How does ICP work?

The specialised probe is inserted into the brain using a small hole drilled through the skull. This is usually done during scheduled surgery. If the probe is only measuring the pressure within the skull, it will be attached to the ‘intracranial pressure monitor’. This monitor may be a separate monitor or be a part of the bedside monitor.

If the probe is inserted into a ventricle of the brain, there will also be a drainage system to remove some cerebrospinal fluid (CSF) if needed. CSF is a clear fluid surrounding the brain to cushion it from the hard skull. This drainage system is called the external ventricular drain (EVD).

When the EVD is first inserted, it is normal for the CSF drained to be slightly pink. If the pressure in the brain increases, the removal of small amounts of CSF will make more room in the skull for the brain and help to reduce the pressure inside the skull.

There is little pain when the ICP probe/drain is in position, but it may be uncomfortable as the tubing needs to be attached to the person’s head to help secure it.

How long will ICP be used for?

The ICP probe and/or drain usually stays in place until the pressure in the brain has reduced.

Are there any complications?

All treatments and procedures done in the intensive care unit (ICU) of a hospital carry a potential risk of complications, even when performed by skilled and experienced staff. Please discuss any concerns with the medical and nursing staff who are caring for the person.

Any questions?

Of course, if you have any questions or concerns, please discuss them with the ICU nurses and doctors.

Click on the buttons for translated fact sheets on ICP monitoring.


Publication details

Intracranial pressure monitoring, version 3. Linda Williams, NUM Liverpool ICU 2016.


The information on this page is general in nature and cannot reflect individual patient variation. It reflects Australian intensive care practice, which may differ from that in other countries. It is intended as a supplement to the more specific information provided by the doctors and nurses caring for your loved one. ICNSW attests to the accuracy of the information contained here but takes no responsibility for how it may apply to an individual patient. Please refer to the full disclaimer.