Jeremy Laurance: It's such an obvious route to take – so why the wait?

Why has it taken so long? That is the first question readers are likely to ask about the Government's decision to extend the retrieval of organs for transplants from intensive care units – the traditional source – to accident and emergency departments.

Most people will be astonished to learn that it doesn't happen already. We have had decades of debate over how to increase organ donation – from opt-in versus opt-out donor registers, to a legalised market – only to discover that there is an ethically simpler, technical solution to the shortage: retrieving them from patients who die in Accident and Emergency.

The reason why this has only become possible now is a mix of changing attitudes and changing fortunes.

The vast sums poured into the NHS over the past decade have made CT scanners widely available for the first time. So patients brought in unconscious to A&E with a brain haemorrhage after suffering a stroke can now be rapidly assessed to determine the extent of the damage. Hopeless cases can for the first time be swiftly and accurately identified.

At the same time, attitudes have shifted over donors. Traditionally organs have been taken from patients certified brain dead – where there is no electrical activity in the brain. In the last few years, this has been extended to include patients whose hearts have stopped, but where brain death has not been established.

"Non-heart-beating" donors expand the pool and make it practical to retrieve organs from patients who die in A&E. However medical staff in most A&E departments are not attuned to the needs of organ donation and need training in how to broach the subject with grieving relatives and carry out the retrieval.

But transplant surgeons are also focused on another prize: retrieving organs from people who die of a heart attack. There are many more of those than who die of a brain haemorrhage and have treatment withdrawn. A pilot study is underway in Newcastle.