Spain's first face transplant patient is doing well after undergoing a 15-hour operation led by surgeon Pedro Cavadas at Valencia's Hospital La Fé, only the eighth operation of its type in the world.

The donor was a 35-year-old man who had died in a traffic accident.

It took Dr Cavadas, one of the most eminent surgeons in Spain, and his team of almost thirty medical staff three hours to remove the donor's face ready to transplant it onto the face of a 43-year-old man, whose identity has not been released.

The patient who has received the transplanted face had to fulfil a series of requirements: he had to suffer from a serious facial injury or burn, be aged between 18 and 50, be resident in Spain and covered by the Social Security system, be a non-smoker, not overweight, not diabetic or suffer from heart problems.

In addition, the patient had to be 'prepared to undergo a surgical procedure with at least two years of post-operative rehabilitation' and live in Valencia for at least 'eight months after the surgery and after that in Spain for as long as he conserves the transplanted face'.

In a press release posted on the Generalitat's website, the patient is reported to be progressing well, although doctors have said that they need to wait for at least 24-48 hours to see how the transplant has taken.

The operation has caught the media's attetion and the national coordinator for the National Organisation of Transplants, Rafael Matesanz, has today expressed his concern about details being released about the donor.

'Privacy is a fundamental part of any transplant operation,' he said, 'but even more so in the case of a face transplant.'

There are two other patients in Spain waiting for face transplants, but there is no competition between them as they do not share the same blood group.

The donor has to be the same sex as the recipient, roughly the same age, have a similar sized face and skin of a similar colour, the same blood group and compatible tissue.  The surgery is highly complex as many different types of tissue have to be connected: muscles, skin, nerves and veins.

Only seven previous face transplants have been performed in the whole world - four in France, two in the UK and one in China.