What is a central line?

A central line is a long, thin, hollow tube made from silicone rubber. They are also called skin-tunnelled central venous catheters. But you may hear them called by brand names such as Hickman® or Groshong® lines. They are used to give chemotherapy treatment or other medicines.

The central line is put in (tunnelled) under the skin of the chest and into a vein close by. One end of the line goes into a large vein just above the heart. The other end comes out of the chest.

The line is usually sealed with a special cap or bung. This can be attached to a drip or syringe containing your medication. There may be a clamp to keep the line closed when it is not being used.

Sometimes, the central line divides into a further 2 or 3 lines. This allows you to have different treatments at the same time.

What is a central line used for?

A central line can be used to give you treatments such as:

  • chemotherapy
  • blood transfusions
  • antibiotics
  • intravenous (IV) fluids
  • liquid food if you are not able to eat.

It can also be used to take samples of your blood for testing. This means that you will not need to have needles put in every time you have treatment.

You can go home with the central line in and it can be left in for weeks or months.

A central line may be helpful if doctors and nurses find it difficult to get needles into your veins. It is also helpful if you do not like needles.

How is a central line put in?

A specialist nurse or doctor will put your central line in at the hospital. They usually do this under a local anaesthetic, but sometimes they use a general anaesthetic. If you have a local anaesthetic, you may also be given sedation to help you relax.

Your doctor or nurse may use a small ultrasound machine to help them find a suitable vein in your neck. Then they clean the skin in the area where the line will be put in with an antiseptic solution.

They numb this area with a local anaesthetic. You should not feel any pain when they are putting the tube in, but you may feel a bit sore for a few days afterwards.

When the area is completely numb, a small cut is made in the skin near your collarbone. This is called the insertion site. The tip of the line is gently threaded into a large vein, towards the heart. The other end of the line is then tunnelled under the skin to where it comes out of the body (exit site). You will have a chest x-ray to make sure the line is in the right place. The diagram below shows these positions of the central line.

The position of the exit site will vary. You can ask your specialist doctor or nurse to show you where on your chest the exit site is likely to be.

When the line has been put in, you will have dressings covering the insertion and exit sites. For a few days after, you may have some pain or discomfort where it has been tunnelled under the skin. You can ask your doctor or nurse which painkillers you should take to help with this.

A central line

What stops a central line from falling out?

There is a small cuff around the central line. It can be felt under the skin, just above the exit site. The tissue under the skin grows around this cuff in about 3 weeks and holds the line safely in place.

Until this happens, you will have a stitch holding the line in place. This stitch usually stays in place for about 3 weeks.

Looking after your central line

When the central line is not being used, there is a small risk of it becoming blocked. To stop this from happening, a small amount of fluid is flushed into the line using a syringe. This is usually done once a week. The caps or bungs at the end of each line should also be changed every week to reduce the risk of infection.

The exit site needs to be cleaned once a week to reduce the risk of infection. If you have a dressing on the site, it will also need to be changed once a week.

Sometimes, a special dressing, such as an antibiotic disc, may be put over the exit site. The dressing helps to reduce the risk of infection.

If you feel able, the nurses at the hospital will teach you how to flush the line and change the dressings. They can also show a family member, partner or friend how to do this. If you prefer, a district nurse can do it for you at home.

Showers, baths and swimming

When you are at home, it is safe for you to have a shower or bath with your central line in. You can place your line in a plastic bag and tape it to your skin so that the line does not get wet. Or your nurse can give you waterproof dressings to stop the line getting wet. You should keep the exit site out of the water in a bath.

Swimming should usually be avoided because there is a risk of infection. It is best to avoid other sports such as golf, tennis or strenuous gym exercises. This is because there is a risk that your central line could become dislodged. Your doctor or nurse can give you information about the exercises you can do.

Possible problems with a central line


It is possible for an infection to develop inside the central line or around the exit site. Contact your hospital doctor or nurse if you have:

  • swelling, redness or pain at the exit site
  • discoloured fluid coming from the exit site
  • a high temperature (fever).

If you get an infection, your doctor will prescribe you antibiotics. If the infection does not get better, the line may be removed.

Blood clots

It is possible for a blood clot (thrombosis) to form in your vein at the end of the line. You may be given medication to help prevent this. Contact your hospital doctor or nurse if you have:

  • swelling, redness or tenderness in the arm, chest area or up into the neck (on the same side as the central line)
  • shortness of breath
  • tightness in your chest.

If a clot does form, you will be given some medication to dissolve it. Your line may have to be removed.

Blocked central line

The inside of the line can sometimes become partly or completely blocked. If this happens, it can be difficult to give treatment or to take blood tests through it. The line may be flushed with a solution to try to clear the blockage, or it may need to be removed.

Air in the central line

It is important not to let any air get into your central line. This is an uncommon problem but could be very serious. The clamps should always be closed when the line is not being used. The line must not be left unclamped when the caps or bungs are not in place.

Groshong® lines do not have clamps. They have a special valve inside the line that stops air getting into it.

Break or cut in the central line

It is important that the central line is not broken or cut. Do not use scissors near the line. Only use the clamp on the thicker, strengthened part of the line.

It is not very common to get a cut or split in the line. If this happens, try to clamp or tie your line just above the break. This is to seal it between the split and where the line comes out of your body. Contact your hospital straight away. The nurses may be able to repair the line. If this cannot be done, it will be removed.

How the central line is removed

When you do not need the central line anymore, it will be taken out. A doctor or specialist nurse will do this for you. It is usually done in the outpatient department and takes about 30 minutes. You will not usually need a general anaesthetic.

Once you are lying down comfortably, the skin over your chest will be cleaned with antiseptic. The doctor or nurse will then numb the area around the cuff with local anaesthetic. They will make a small cut to release the cuff, then slowly remove the line. You might find this uncomfortable, but it should not be painful.

Once the line is out, your nurse or doctor will put a dressing over the exit site. You will be asked to stay lying down for about 10 minutes until they are sure there is no bleeding.