Usually central lines are trouble-free but problems do sometimes occur. The three commonest difficulties are infection, thrombosis and change of position.

Three types of infection may occur. Firstly, an infection may affect the skin and soft tissues around the exit of the line, on the chest. This will show up as inflammation, with redness, soreness and swelling around the exit site of the line. A second site for infection is in the soft tissues under the skin, where the line tracks up the chest to enter the vein. Once again redness, soreness and swelling are the signs suggesting that this has developed. The third type of infection is known as a line infection and this leads to infection of the blood known as septicaemia, which makes you feel very unwell, with a high temperature, sweating and weakness. All these infections are treated by giving the appropriate antibiotics. It is important to start treatment quickly so if you suspect you might have developed an infection then you should contact your chemotherapy team immediately.

Thrombosis, or the formation of blood clots, most often occurs in the entry vein in the shoulder (the subclavian vein). It is possible to take a small dose of an anticoagulant (anti-clotting medication) every day to reduce the likelihood of clots forming. Some doctors believe this should be routine but others feel it is only necessary if someone is at an increased risk of clotting. Subclavian vein thrombosis leads to pain in the shoulder area and often there is some swelling of the arm on that side. A temperature is also quite common. Once doctors have confirmed that there is a thrombosis then anticoagulant drugs will be given to relieve the problem.

If an infection or a thrombosis occurs it is often necessary to remove the line. But once the problem has been treated then it is usually possible to put in another line.

However carefully a line is positioned and fixed, occasionally they will move. Sometimes the line slips further into the tissues so that the internal end of the line moves out of the large vein called the vena cava or becomes kinked or twisted. On other occasions the lines can partially or even completely slip out. Usually it is possible to simply reposition the line if the movement has been small, but sometimes it will be necessary to replace it completely.

Changes in position of a line, or thrombosis in the subclavian vein can cause the line to become blocked but this can also happen if small amounts of blood leak back into the line, from the veins, and form small clots. Regular flushing of the line will help prevent this and your nursing team will give you detailed instructions about this.

Before you have a line inserted the nursing and medical team will fully explain the possible problems and check that you are still happy to go ahead. Once the line is in place they will keep a careful check on it and also make sure you have a 'phone number to reach them if you have any problems between visits.