Patients left in a “vegetative” state after suffering devastating brain damage are able to understand and communicate, groundbreaking research suggests.
'Vegetative state' brain scan images:: the fMRI images which were used as part of the study by Dr Adrian Owen.
They were able to give yes or no responses to simple biographical questions.
The unlocking of this “inner voice” has astounded doctors and has dramatic implications for thousands of life and death decisions over patients trapped in what is known as a persistent vegetative state (PVS).
It means around one in five PVS patients may be able to communicate.
It will raise questions about when doctors should switch off life support machines. It is likely to add to the debate on assisted suicide as the patient could potentially decide and communicate if they wish to carry on living. It comes just weeks after Kay Gilderdale was acquitted of assisting the suicide of her daughter Lynn who the jury accepted had lived a “twilight life” for more than 17 years.
Up to a thousand PVS patients in Britain are kept alive by doctors in the hope they may one day regain consciousness.
But in some cases, like Hillsborough victim Tony Bland, relatives have won the right to withdraw treatment to allow them to die.
Dr Adrian Owen, co-author at the Brain Sciences Unit in Cambridge who carried out the latest research on one patient, said the findings have enormous philosophical and ethical implications.
He said: “We were astonished when we saw the results of the patient’s scan and that he was able to correctly answer the questions that were asked by simply changing his thoughts.
“Not only did these scans tell us that the patient was not in a vegetative state but, more importantly, for the first time in five years it provided the patient with a way of communicating his thoughts to the outside world.
“We can be pretty confident that he is entirely conscious. He has to understand the instructions, comprehend speech, and then make a decision.”
He added: “Obviously this fits into the issue of when patients should be allowed to die.”
While pointing out that it could help doctors discover if a patient is in pain, he admitted it was quite a leap to say 'let this patient decide whether he lives or dies’.”
The British and Belgian researchers made their discovery, published in the New England Journal of Medicine, after studying a 29-year-old man brain damaged in a car crash in 2003.
The man was in a coma for two years before slipping into a persistent vegetative state. He was seemingly awake, occasionally blinked, but showed no other sign of being aware of the outside world.
But the team, led by Dr Owen, whose work was funded by the Medical Research Council, and Steven Laureys of the University of Liege, discovered it was possible to talk to him by tapping into his brain activity.
They used a hi-tech functional magnetic resonance scanner (fMRI) to measure brain response while the patient was asked questions.
The scan uses magnetic fields and radio waves to detect electrical pulses.
Because the actual brain signals associated with “yes” and “no” are complicated and too similar to distinguish, they came up with a code they could understand.
The team asked the patient to think of playing tennis for “yes” and moving around their home for “no”.
While the movement in tennis sparks 'spacial’ areas at the top of the brain, the “navigational task” of moving around your home sparks the 'motion’ areas at the base of the brain.
The patient was then asked six simple biographical questions including what was the name of his father and whether he had any sisters. In each case, his thoughts were picked up by the scans within five minutes. In each case he was 100 per cent accurate.
The team then tested 22 PVS patients for similar brain activity and, while they did not ask them the questions, believe 17 per cent will be able to communicate with doctors.
It comes just two months after Rom Houben, a Belgian man, presumed to be in PVS for 23 years after a car crash “woke up” and told how he was conscious throughout his ordeal.
Researchers using new diagnostic techniques discovered that his brain was still active and trained him to use his right forefinger to express himself on an adapted keyboard.
Jacob Appel, an expert in medical ethics at the Mount Sinai Hospital in New York, said that doctors should help end the lives of people trapped in their bodies, if they think that is what they want.
“This will indeed be a clear-cut case where a patient can express a desire to end his or her life, but has no physical means of doing so. I see no reason why, if we are truly convinced such patients are communicating, society should not honour their wishes. In fact, as a physician, I think a compelling case can be made that doctors have an ethical obligation to assist such patients by removing treatment. I suspect that, if such individuals are indeed trapped in their bodies, they may be living in great torment and will request to have their care terminated or even active euthanasia.”
But sources at the British Medical Association, the doctors’ union, said it is unlikely that many medics would consider the results of a brain scan experiment as sufficient evidence of mental capacity.
Professor Geraint Rees, Director of the Institute of Cognitive Neuroscience at University College London, said: “As a clinician, it would be important to satisfy oneself that the individual that you are communicating with is competent to make those decisions.
“At the moment it is premature to conclude that the individual able to answer 5 out of 6 yes/no questions is fully conscious like you or I.”
Dr Peter Saunders, Director of the Care Not Killing Alliance which opposes euthanasia, claimed the breakthrough would be unlikely to alter contentious guidelines on assisted suicide, as patients in vegetative states are not likely to be considered to have sufficient mental capacity to make life-or-death decisions.
It comes a day after the Roman Catholic Church in England and Wales published guidance on the spiritual care of the dying, which said that food or nutrition should never be removed in order to shorten a person’s life.
Its document quotes the late Pope, John Paul II, who said it is “morally obligatory” to provide nutrition and hydration to patients in a vegetative state.
It is doubtful that the so-called “mercy killing” of Mr Bland in 1993 could have been affected by the new breakthrough as he was thought to be in an extreme form of the “persistent vegetative state”.
No comments:
Post a Comment