Abscess drainage using image guidance

What is an abscess?

An abscess is a collection of infected fluid and dead cells (pus) somewhere in the body. It is often swollen and painful. Abscesses usually do not heal by themselves, and they may keep getting worse unless they are treated. Treatment starts with antibiotics. However, in some cases, an abscess cannot be cured with antibiotics alone. Instead, it may need to be opened so the pus can drain, allowing it to start healing.

Abscess drainage

An abscess can form in any part of the body. Using image guidance, a tube is placed into the abscess to drain it. This helps control the infection, prevents it from spreading and promotes healing.

Abscess drainage

An abscess drainage procedure is a way to remove pus from the abscess.

If the abscess is just under your child's skin, a doctor can usually open and drain it using a scalpel (surgical knife). However, if it is deep in your child's body, it will be drained by an interventional radiologist using image guidance.

Draining the pus will usually help the abscess heal and make your child feel better sooner. A sample of the pus is often sent to the laboratory to help find out what is causing the infection.

How an abscess is drained

The interventional radiologist uses ultrasound or computed tomography (CT) to see where the abscess is. These pictures guide the interventional radiologist in directing a small needle through the best route into the abscess (usually through the skin).

Most often, a small soft tube (drain) is placed in the abscess using ultrasound and X-ray guidance. This drain is then attached to a drainage bag to allow the pus to drain away from the abscess. The drain will stay in your child's body until most of the pus has drained.

For most abscess drainages, your child will not need any stitches.

The procedure will usually take one hour.

Risks of abscess drainage

Abscess drainages are usually low-risk procedures. The risk may increase depending on your child’s condition, age and health.

The risks of any abscess drainage can include:

  • bleeding in or around the abscess
  • abscess breakage, which can cause spread of the infection or a systemic infection (sepsis)
  • injury to a nearby organ
  • creation of a connection between the bowel and skin (fistula) if the abscess is located in the abdomen

Giving consent before the procedure

Before the procedure, the interventional radiologist will go over how and why the procedure is done, as well as the potential benefits and risks. They will also discuss what will be done to reduce these risks, and will help you weigh any benefits against the risks. It is important that you understand all of these potential risks and benefits of the abscess drainage and that all of your questions are answered. If you agree to the procedure, you can give consent for treatment by signing the consent form. A parent or legal guardian must sign the consent form for young children. The procedure will not be done unless you give your consent.

How to prepare your child for the procedure

Before any treatment, it is important to talk to your child about what will happen. When talking to your child, use words they can understand. Let your child know that medicines will be given to make them feel comfortable during the procedure.

Children feel less anxious and scared when they know what to expect. Children also feel less worried when they see their parents are calm and supportive.

Food, drink and medicines before the procedure

  • Your child’s stomach must be empty before sedation or general anaesthetic.
  • If your child has special needs during fasting, talk to your doctor to make a plan.
  • Your child can take their regular morning medicine with a sip of water two hours before the procedure.
  • Medicines such as acetylsalicylic acid (ASA), naproxen or ibuprofen, warfarin, or enoxaparin may increase the risk of bleeding. Do not give these to your child before the procedure unless they have been cleared first by their doctor and the interventional radiologist.

Your child will have medicine for pain

Children are given medicine for treatments that may be frightening, uncomfortable or painful. This includes local anaesthesia, sedation and/or general anaesthesia. The type of medicine that your child will have for the procedure will depend on your child’s condition.

On the day of the abscess drainage

When your child arrives at the department they will be dressed in a hospital gown and assessed by a nurse. Your child may have an intravenous started and may have some freezing cream put on the skin near the abscess. You will also be able to speak to the interventional radiologist who will be draining the abscess and the anaesthetist or nurse who will be giving your child medication to make them comfortable during the procedure.

During the abscess drainage, you will be asked to wait in the surgical waiting area.

After the abscess drainage

Once the abscess drainage is complete, your child will be moved to the recovery area. The interventional radiologist will come and talk to you about the details of the procedure. As soon as your child starts to wake up a nurse will come and get you.

The interventional radiologist will come to see your child later on to ensure the drain is working properly. The drain usually stays in until most of the pus has drained out of the abscess. Most children stay in the hospital while the drain is in.


Your child may require antibiotics following the drainage.

Taking out the drain

When the tube is no longer needed, it is removed at your child’s bedside. A small bandage is placed over the drain site.

Going home

In most cases, children go home only after the drain is removed. Your doctor will let you know when they are well enough to go home. For more details on how to care for your child after an abscess drainage, please see Abscess drainage: Caring for your child at home after the procedure.

Key points

  • An abscess is a collection of pus somewhere in the body. Sometimes it needs to be drained. When the collection is deep, an interventional radiologist uses image guidance to drain the abscess.
  • Draining an abscess is usually a low-risk procedure.
  • You will be asked to sign a consent form before the procedure.
  • Your child will likely have a drain inserted in the abscess.
  • The procedure is done using local anaesthetic, and your child will receive a general anaesthetic or sedation.
  • Be calm, honest and tell your child what to expect. Children feel less nervous and scared when they are given information about what will happen to them.

Michelle Cote, BScN, RN

Joao Amaral, MD


At SickKids

At SickKids, the interventional radiologists work in the Department of Diagnostic Imaging – Division of Image Guided Therapy (IGT). You can call the IGT clinic at (416) 813-6054 and speak to the clinic nurse during working hours (8:00 to 15:00) or leave a message with the IGT clinic nurse.

For more information on fasting see Eating and drinking before surgery.

For more information on preparing your child for their procedure see Coming for surgery.