Extravasation guidance

This leaflet has advice for what to do if the dye that has been injected into your veins escapes into your surrounding soft tissue. 

What is extravasation? 

For certain MRI and CT scans we may need to inject you with a dye, to help with the diagnosis. We usually inject it into a vein in your arm or hand. Sometimes this dye can escape from your vein at the place where we inject you. This is known as ‘extravasation’ and can result in a swelling. It can also cause temporary pain but this should not last more than half an hour. 

Immediate help from staff 

If you do experience extravasation we will apply pressure to the place where you have been injected, and lift your affected arm. We will sometimes apply a cold compress and, if possible, we will complete the scan. We may need to give you another injection but we will discuss this will you. 

For severe incidents a doctor will review your arm before you leave the department. 

What you can do at home 

This is usually a minor injury that doesn’t require treatment but to reduce any pain you can:

• Massage the affected area.
• Lift your arm if it is swollen. At night you can use pillows to elevate it.
• Apply an ice pack or a bag of frozen vegetable for no longer than 15 minutes at a time. Do not apply the ice pack or frozen vegetables to the skin directly - a clean cloth must be used to prevent you getting frostbite on your skin.
• You can take over the counter painkillers to help with any pain.

Things to be aware of

Seek medical attention from your GP or an emergency department if you experience any of the following:

• Increased pain, which is not eased by painkillers.
• Increased swelling of your arm or hand.
• Change in colour of your arm or hand.
• Pins and needles or altered sensation in your arm or hand.
• Blistering or an ulcer developing close to the injection site.

Important information 

The radiographer will write down the following information and give it to you. You should take this with you to any future appointments you have related to the extravasation: 

• The date.
• The type of contrast.
• The amount of contrast extravasated.
• The amount of saline extravasated.
• The site of the extravasation. 

© North Bristol NHS Trust. This edition published March 2024. Review due March 2027. NBT003212.