Arguments about whether organ donor systems should be based on presumed consent are missing the point when it comes to increasing donation rates, says a leading UK clinical scientist.

In a paper published today in the British Medical Journal, Professor John Fabre of the School of Medicine in Kings College, London, examines Spain's organ donor system against that in the United Kingdom.

Spain has the world's highest rate of deceased organ donation, two and a half times higher than in the UK.

Professor Fabre says that Spain's excellent record on organ donation does not depend on its 'presumed consent', or 'opt-out', legislation, which was introduced in 1979.

He argues that a donor's family is always asked for consent, and that the family's wishes are final.

In the United Kingdom, which has an 'opt-in' organ donor policy, there is a refusal rate of about 40 per cent. Refusal rate is a measure of the percentage of families of eligible potential donors who refuse to make the organs available.

Spain's refusal rate is about 15 per cent, while in Australia the rate is similar to the UK.

Gerry O'Callaghan, national medical director of the Australian Organ and Tissue Authority, known as Donate Life, says Spain has achieved that not because of presumed consent, but because they concentrated on society's attitudes.

"Organ donation has become a routine part of the conversation around end-of-life care in Spanish hospitals," he said.

"Over the course of the last 20 years, they have trained thousands of doctors and nurses about the benefits in a medical sense, improved quality of life, the improved mortality rates in transplant recipients."

The paper in the British Medical Journal says in 1989, donation rates in Spain and the UK were both about 14 per million population. That represents a refusal rate between 30 and 40 per cent.

In Spain, that figure changed dramatically after the country introduced a comprehensive, national organ donation campaign.

In the 12 years since, Spain's refusal rate fell by more than half, while Britain's has remained high.

Intensive care rethink

Professor Fabre also puts the difference down to Britain's low provision of intensive care beds, about 27 per million population, compared to more than 87 in Spain.

He argues doctors in the UK are less likely to allocate an intensive care bed to a patient with a poor prognosis. They are also more likely to stop life support before brain stem death.

Mr O'Callaghan says the Australian transplant rate is improving, but agrees that the number of available intensive care positions makes a crucial difference.

"That is an important point about whether or not the clinical resources are available in order to provide life support to individuals in these situations," he said.

"I think that's a much more insightful point about why donation rates are different in England and Australia or Spain."

Transplant Australia's Chris Thomas says the issue of intensive care beds needs to addressed.

"That's something that I don't think Australian regulators have fully examined," he said.

"There's huge pressure on intensive care beds and when a doctor is left with the crucial decision of whether to keep an intensive care bed occupied by a potential donor while the family makes a decision, or vacate that bed for the next injured person coming in, that decision is crystal clear.

"It would be worthy of a study of whether or not that's putting an artificial ceiling on donation rates."