The effects of flickering screens on our eyesight, RSI and Carpal Tunnel Syndrome are a constant fear for many keyboard operators.

But now doctors in New Zealand have released the most frightening story of all: Using a PC could kill you.

Apparently, the trouble lies in the way we use our PCs.

We sit for hours at a time without moving and, according to Dr Richard Beasley, of the Medical Research Institute of New Zealand, this could put people at risk of developing deep vein thrombosis (DVT).

It is normally associated with long-haul air travel but people who work or play for excessively long periods at their PCs are also at risk from blood clots, according to the new report published in The European Respiratory Journal.

It tells how a young man in New Zealand almost died after developing DVT following extended periods of PC use.

This first recorded case of e-thrombi occurred after he spent as much as 18 hours a day sitting at a computer.

He developed a large blood clot that formed in his leg vein, broke off and moved to his lungs.

The extent of the problem is not yet known but initial findings suggest this is not an isolated incident.

This case is likely to be the start of a new spate of DVT-related concern about long periods of time spent immobile while at work.

Employers could even face new legislation insisting workers be allowed to take more frequent breaks.

Dr Beasley said: It could be similar to the situation with the risk of blood clots and air travel. It was not until there was publicity with individual cases that the real extent of the problem was recognised.

Dr Beasleys team is now about to review the records of other patients who had pulmonary embolisms to see if they can find other e-thrombosis cases.

Dr Dan Rutherford, of NetDoctor, who has written about DVT, says personal responsibility is needed.

He said: People need to check their chairs do not compress the upper and sides of their legs and that there are no sharp edges to the front of the chair.

They should take regular breaks. Five to ten minutes an hour to walk around is sufficient.

DVT occurs when a persons circulation slows down due to illness, injury, or inactivity. There is then a tendency for blood to accumulate or pool.

The major risk associated with DVT is development of pulmonary embolism.

This is where a fragment of a blood clot breaks loose from the wall of the vein and migrates to the lungs, where it blocks a pulmonary artery or one of its branches.

Symptoms of DVT may include pain, swelling, discoloration of the affected area and skin that is warm to the touch. But up to 50 per cent of deep vein thromboses produce minimal symptoms or are completely invisible.

Advice on DVT is available from BUPA and the Department of Health.

If you have any suspicion you may be at risk, get advice from your doctor immediately.

For more information, visit:

www.doh.gov.uk/dvt/hcd2.bupa.co.uk
www.veinguard.com
www.thrombosisonline.com