The blood transfusion is a standard procedure in our hospitals, and many of us regard it as our social duty to give blood.
Around 2.5 million units of blood are collected in the UK every year, and around half is used during elective and emergency surgery, and 5 per cent in intensive care.
The transfusion saves lives when a patient is hemorrhaging, when the marrow is suppressed, and when haemoglobin levels are dangerously low. Other than that, there is no evidence that a transfusion will do any good. One large study, carried out in 1999, discovered that critically ill patients fared better without a transfusion, while another study at an intensive care unit found that transfusions failed to oxygenate the blood.
Worse, there's quite a lot of evidence to suggest that a transfusion can make the patient worse, and in rare cases even cause the patient's death. The UK SHOT (Serious Hazards of Transfusion) survey has found that 46 people died as a direct result of a transfusion between 1996 and 2003, while 253 suffered a serious reaction, including acute lung injury and infection.
Then there is the problem of blood that is contaminated with HIV and hepatitis. It costs the UK health authorities around £500m a year just to 'clean' the blood, so almost eliminating any infections - although there's no such thing as blood that's guaranteed to be infection-free. It's known, for example, that 17 blood donors later went on to develop variant Creutzfeldt-Jakob disease. Fifty recipients of their blood have been traced, and at least two have been infected, and one of these has since died.
All of this seems like a lot of money, and unnecessary risk, for a procedure that isn't even warranted in so many cases.
(Source: British Medical Journal, 2005; 330: 104-5).