New South Wales Government
Agency for Clinical Innovation
About ICCMU | contact us
Home > Community > Patient Treatment > Arterial line insertion

Arterial line insertion


An arterial line is a fine plastic tube, called a cannula, which is inserted into the patients’ artery. The cannula is attached to a transducer and infusion line (drip). Arterial lines can also be referred as ‘arterial catheter’, ‘arterial cannulae’ or ‘art lines’.

What is it?

An arterial line is a fine plastic tube, called a cannula, which is inserted into the patients’ artery. The cannula is attached to a transducer and infusion line (drip).

Why is it done?

There are two main purposes of an arterial line. Firstly when patients are very sick an arterial line is inserted to provide constant monitoring and recording of the patient’s blood pressure. Secondly some patients require frequent blood tests and the arterial line provides easy access to a patient’s blood. Thus reducing the number of times a blood vessel will be accessed with a needle and reducing patient pain. Arterial blood gases (ABG) are important blood tests that assist in monitoring the patient’s oxygen status. An ABG can only be taken from an artery.

What is done?

The doctor inserts the arterial cannula into an artery usually in the wrist, (radial) or in the patients’ groin, (femoral). The insertion site is cleaned with antiseptic to prevent infection. The doctor may give you a small amount of local anaesthetic which can “sting’ and this will numb the area when the doctor inserts the cannula into the artery. Once the arterial line is inserted it will be connected to an infusion line (drip), which continuously infuses fluid into the artery to prevent the cannula from blocking. The transducer allows for an arterial waveform to be displayed on a monitor that provides continuous monitoring of the patient’s blood pressure.

The arterial line is secured, covered with a plastic dressing and can be held in position by an armboard and a bandage.

What are the risks?

All Intensive Care interventions and procedures carry a degree of potential risk even when performed by skilled and experienced staff. Any possible complications will be discussed with you by the Intensive Care staff caring for the patient.

This picture shows the insertion of an arterial line into a patient's radial artery (in the wrist).

This picture was found at

Go to top

How is the arterial line removed?

A nurse removes the arterial line. The nurse pulls the catheter out of the artery and will apply firm pressure, for about 3-5 minutes, to your artery to prevent bleeding. A small dressing will be placed over the site, which can be removed the next day.

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

The information contained on this page is general in nature and therefore cannot reflect individual patient variation. In addition it reflects Australian intensive care practice which may differ from other countries. It is meant as a back up to specific information which will be discussed with you by the Doctors and Nurses caring for your loved one. ICCMU 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.

Arterial Line Insertion Version 1 (Author: Helena Sanderson CNE Tamworth ICU, NSW, Australia)

First published July 2007

Correspondence: ICCMU CNC

Go to top

Last Updated on Wednesday, 18 December 2013 23:49