Port-a-Cath insertion

A Port-a-Cath is small medical device that is put under the skin. It is used to give medicines to patients whose veins are weak or very narrow, or for those on long-term treatment or therapy.

A Port-a-Cath is made up of 2 parts:

  1. A soft, thin hollow plastic tube (catheter) which is tunnelled under the skin. The tip of the catheter is positioned just outside the heart.
  2. A port or disc (2.5 to 4cm in diameter), which is placed in the chest and attached to the tube.

A Port-a-Cath is the main type of central venous access device. Central venous access devices are small, flexible tubes placed in large veins for people who need frequent access to the bloodstream.

The catheter tip will lie in a vein, just above your heart, and the other end connects to the port or disk, in the chest. The Port-a-Cath looks like a small bump underneath the skin. This helps the nurse to know where to insert the needle because it can be felt under the skin.

Benefits of having a Port-a-Cath

A Port-a-Cath is usually recommended for patients who regularly have chemotherapy, long-term antibiotics and infusions. A Port-a-Cath can be left in for a long time, so it can be used throughout your treatment.

Blood samples can be taken many times using the Port-a-Cath, without having needles repeatedly inserted into your veins every time you need treatment. This means blood can be taken with less discomfort.

Risks of having a Port-a-Cath

Serious risks and complications of having a Port-a-Cath inserted are very rare. However, as with any procedure, there are some risks and it is important you understand them. The radiologist will explain these to you.

Radiation risks

During the procedure, you are exposed to X-rays. They are a type of radiation called ionising radiation. This may cause cancer many years or decades after you are exposed to it.

You might have some skin redness after the procedure that feels like sunburn. The redness might be harder to notice on brown and black skin. This is not usually permanent.

Interventional radiology (IR) is when we use medical imaging guidance to do minimally invasive procedures. The dose (amount) of radiation from these procedures is generally low. More complex procedures might involve a medium (moderate) dose of radiation.

The IR doctor and radiographer make sure that:

  • your radiation dose is kept as low as possible
  • the benefits of having X-rays during your procedure are greater than the radiation risks


There is a chance of getting a skin infection, or an infection within your bloodstream. We can treat these with antibiotics. In extreme cases, we might need to remove your Port-a-Cath.


You will have 2 permanent, small scars on your skin, where the Port-a-Cath was inserted:

  • a 2cm to 3cm scar in the chest wall
  • a scar at the base of the neck, which is usually less than 5mm


You might have some bruising on your skin in the area the Port-a-Cath was inserted. This is quite common and normally settles a few days after the procedure.

Thrombosis or clot

Sometimes a clot of blood can form at the tip of the Port-a-Cath. To prevent this, a blood thinning solution can be locked inside the port and the catheter when it is not in use.

Lung puncture

This happens when the lung is accidentally punctured during the procedure. It is very rare and happens to 1 in 1,000 patients. If this happens, we might keep you in hospital for a few days until the lung has healed.

Radiation and pregnancy

Radiation can be harmful for an unborn baby. If you are or think that you might be pregnant, it is important to tell a member of your medical team before the procedure. We cannot do any procedure that involves radiation if you are pregnant.

If you can become pregnant from sex, you need to use protection (contraception) from the first day of your period until your appointment. This means that you will not be pregnant when you have the procedure.

If the first day of your period has already passed, please contact the interventional radiology (IR) department. We can then give you another appointment within the first 10 days of your period.

We ask you to sign a pregnancy declaration form before the procedure.

Other treatment options

The other treatment option would be repeatedly inserting needles to the vein every time you have treatment.

Some treatments need access to larger veins, so for these treatments there is no alternative to a Port-a-Cath.

We want to involve you in decisions about your care and treatment. If you decide to have the procedure or treatment, we will ask you to sign a consent form. This says that you understand what is involved and agree to have the treatment.

Read more about our consent process.

Resource number: 2994/VER5
Last reviewed: February 2024
Next review due: February 2027

Contact us

If you have any questions or concerns about having a Port-a-Cath inserted, please contact the interventional radiology department.

At Guy’s Hospital, phone: 020 7188 5576, Monday to Friday, 9am to 5pm

At St Thomas’ Hospital, phone: 020 7188 5479 Monday to Friday, 9am to 5pm

Do you have any comments or concerns about your care?

Contact our Patient Advice and Liaison Service (PALS)

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