Stephen Cauchi
The Age
"IT TAKES someone special to give blood" says the Australian Red Cross Blood Service's slogan — which makes 500,000 Australians every year quite special. But could their altruism be misplaced?
The answer, according to American cardiothoracic specialist Bruce Spiess, may well be yes. During last week's annual scientific meeting of the Australian and New Zealand College of Anaesthetists, Professor Spiess, from the Virginia Commonwealth University, poured scorn on the belief that blood, or at least the transfusion of it, was the elixir of life.
"Blood transfusions are a religion. They have never been safety or efficacy tested," he said. "Drug options are carefully tested and regulated through prospective, randomised double-blind testing, but blood transfusion stands apart in that it has predominantly been believed to be helpful and evolved as a pillar of modern medicine."
Professor Spiess cited a Swedish study involving Jehovah's Witnesses, whose religion forbids them to accept transfusions. It showed that 499 Witnesses who had open-heart surgery had better survival rates than other open-heart patients.
The problem with transfusions is not transmission of diseases such as HIV or hepatitis, which are screened for by blood banks, but post-operative complications such as pneumonia, wound infection and organ failure, some of which can be fatal.
Blood transfusions could indeed cause "major morbidity or even mortality", said Professor James Isbister, of the University of Sydney. "Increasingly, evidence and experience is suggesting that blood banking and transfusions medicine have excessively focused on supply rather than the demand/patient perspective."
Because blood is given free, it is a cheap alternative to treatments such as drugs. A statement from the Australian and New Zealand College of Anaesthetists said: "In Australia, the economics of blood discourages the use of alternatives because Australians donate blood and the Red Cross gives it to hospitals free … alternatives to transfusion include minimising blood loss and maximising oxygenation."
Professor Spiess told the conference of anaesthetists — the profession responsible for half the transfusions associated with surgery — that campaigns to encourage blood donation had helped shape the notion that all transfusions were good. Women received more transfusions than men, with worse outcomes from heart surgery a particular problem.
The Australian Red Cross Blood Service, which administers the nation's blood banks, referred The Sunday Age to Larry McNichol, head of anaesthesia at the Austin Hospital. Dr McNichol, who is also chairman of a Department of Human Services committee on transfusions, said his friends were "gobsmacked" when he told them about the problems with blood.
"They were saying, 'How can you say blood isn't fantastic, it saves people's lives'," he said.
"It is fantastic, it's a gift and it's saved lots of lives. But it's also important to realise that for everything there is a side-effect. It's just that it's taken us a long time to start building up the evidence for the potential adverse effects of having a transfusion."
Transfusion is needed when hemoglobin — the oxygen-containing protein in red blood cells — falls below a certain level, endangering the body's ability to transport oxygen. But the level at which transfusion is required, said Dr McNichol, is debatable.
"We were always taught that if (hemoglobin) drops below 10 (grams per deci-litre) you should perhaps give (the patient) some blood. What we're really saying, and Bruce Spiess articulated it really well, is that there is no scientific basis for the figure of 10. Somebody just said, it sounds around about the right figure."
There is evidence, said Dr McNichol, that some anaesthetists were giving blood when the count fell as low as seven. In general, the right level depended on the patient's condition.
For Jehovah's Witnesses in surgery, there is a range of strategies. Drugs can be taken that boost hemoglobin, reducing the need for transfusion or reducing surgical bleeding. During some forms of surgery, the patient's blood can be collected, washed, and pumped back into the body.
There are also ways to treat blood so it becomes less likely to cause side-effects. One is the removal of white blood cells. The other is bacterial testing of platelet bags. Both measures have received federal funding, bringing Australia into line with Britain, Europe, Canada and most of the US. Despite such measures, the growing consensus is: transfuse only when necessary.
"It's not an insignificant thing to have to give a patient a unit or two of blood because these things can be bad for you," Dr McNichol said. "What the emphasis is on now is saying what can we at the clinical coalface do to minimise the chances of patients having to have blood."
"They were saying, 'How can you say blood isn't fantastic, it saves people's lives'," he said.
"It is fantastic, it's a gift and it's saved lots of lives. But it's also important to realise that for everything there is a side-effect. It's just that it's taken us a long time to start building up the evidence for the potential adverse effects of having a transfusion."
Transfusion is needed when hemoglobin — the oxygen-containing protein in red blood cells — falls below a certain level, endangering the body's ability to transport oxygen. But the level at which transfusion is required, said Dr McNichol, is debatable.
"We were always taught that if (hemoglobin) drops below 10 (grams per deci-litre) you should perhaps give (the patient) some blood. What we're really saying, and Bruce Spiess articulated it really well, is that there is no scientific basis for the figure of 10. Somebody just said, it sounds around about the right figure."
There is evidence, said Dr McNichol, that some anaesthetists were giving blood when the count fell as low as seven. In general, the right level depended on the patient's condition.
For Jehovah's Witnesses in surgery, there is a range of strategies. Drugs can be taken that boost hemoglobin, reducing the need for transfusion or reducing surgical bleeding. During some forms of surgery, the patient's blood can be collected, washed, and pumped back into the body.
There are also ways to treat blood so it becomes less likely to cause side-effects. One is the removal of white blood cells. The other is bacterial testing of platelet bags. Both measures have received federal funding, bringing Australia into line with Britain, Europe, Canada and most of the US. Despite such measures, the growing consensus is: transfuse only when necessary.
"It's not an insignificant thing to have to give a patient a unit or two of blood because these things can be bad for you," Dr McNichol said. "What the emphasis is on now is saying what can we at the clinical coalface do to minimise the chances of patients having to have blood."
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