Therapy to stimulate red blood cells already in use

IT'S a procedure which has been used for hundreds of years - but new techniques in medicine mean blood transfusions could no longer be used in 30 years' time.

That's the prediction from leading expert Dr Ivor Cavill, who argued that a "blind faith" in the effectiveness of blood transfusion still exists despite growing evidence that it can do patients harm.

A drive to reduce the number of blood transfusions is already under way across the UK, to help address the chronic blood shortage and reduce the risks to patients associated with transfusions.

The Scottish National Blood Transfusion Service (SNBTS) - which will this week launch a campaign to encourage donors to come forward over Christmas - has reduced blood usage by 10% in the past four years.

Cavill, a senior fellow in haematology at Cardiff University, said that treatments such as erythropoietin (EPO) - which uses hormones to stimulate the formation of red blood cells - were now being used more widely.

"Fifteen years ago it was found that EPO could be used to stimulate the patient's marrow to make more of their own red cells," he said. "In the following five years or so, that virtually abolished the use of blood transfusion in kidney patients.

"Over the past decade, people have begun to realise that we can use various EPOs to stimulate the patient's marrow to make more of their own red cells."

While careful screening of blood and donors is carried out, receiving a transfusion is not without risk: in 2005, five patients' deaths were linked to problems during blood transfusions, such as a severe allergic reaction or being given too much blood. One case of a patient developing variant CJD after a blood transfusion was also reported - as yet, there is no test to detect the presence of this disease in blood.

Research by scientists in Bristol, published last month, found that transfusions of red blood cells given to people having heart surgery could increase the risk of a heart attack or stroke. Professor Peter Weissberg, medical director of the British Heart Foundation which funded the study, said it suggested that these "top-up" transfusions "may cause more problems than they solve".

Cavill argued that it was likely that the demise of the blood transfusion as a therapy would take place in the next three decades. "I think we are on the point of seeing quite a radical change in people's attitudes to blood transfusion," he said. "All the evidence is that blood transfusion can do you harm, yet people believe in it blindly."

Among the other new techniques which are helping to reduce the need for blood is a test known as thrombo-elastography/thromboelastometry (TE), which measures the ability of the blood to clot. Already used in cardiac and lung transplant surgery, a report for health watchdog body NHS Quality Improvement Scotland has recently recommended that it should also be used for major surgery where patients have a high blood loss, such as trauma cases.

Dr Alastair Nimmo, consultant anaesthetist at Edinburgh Royal Infirmary, said that the test - which is carried out in operating theatres or intensive care units - was a quicker process than conventional techniques.

"One of the big problems with sending bloods to the laboratory is that if a patient is losing a lot of blood, the coagulation abnormalities can change very quickly," he said. "So by the time the results come back, they may no longer be relevant and will not be reflective of the current situation.

"By rapidly diagnosing what the problem is and permitting targeted appropriate treatment to be given, it is possible to correct coagulation more quickly and reduce or prevent further blood loss."

Other procedures which are becoming more widely used include blood cell salvage, where the patient's own blood is "washed" by a machine before being reinfused back into the body.

However, scientists are still working on the development of the medical "holy grail" - artificial blood, which could be given to any patient regardless of their blood group and stored easily.

Earlier this year, experts at Sheffield University announced they had developed plastic blood, which could be available in a decade. Although it is not expected to be a long-term substitute for real blood, it is hoped it could keep patients alive until a real transfusion could be carried out.

A spokeswoman for the SNBTS said that training and education programmes were among the initiatives being used to reduce blood usage where it is "safe and appropriate to do so". The latest assessment found that blood usage in Scotland has dropped by 10% since the introduction of the NHS Scotland Better Blood Transfusion Programme in 2003.

"This represents transfusion rates of just over 41 units per 1000 population, which compares well with the best in Europe," she said. "Our aim is to achieve blood usage of 38 per 1000 by 2010."