When Hassan Rasouli, a patient at Sunnybrook Hospital in Toronto, Canada, raised a finger in response to a question, his family was thrilled. Since 2011, they had been fighting a court battle in Ontario against doctors who wanted to let him die because he had previously remained unresponsive for a year after contracting an infection in hospital.
Rasouli's finger movement convinced physicians to upgrade his status from "persistent vegetative state" (PVS), in which a person has signs of partial arousal ? such as involuntary movement ? but no conscious awareness, to "minimally conscious" (MCS), defined by partial conscious awareness ? the ability to respond to instructions, for example. However, his doctors still believe that treatment is futile and that he should be allowed to die.
In Ontario, when someone is incapable of agreeing to a treatment and that person's surrogates cannot agree with doctors, they can go to the Consent and Capacity Board as an arbitrator. In this case, however, the doctors argue that withdrawing a futile treatment is not a treatment in itself, and thus does not require anyone's consent.
The decision is now in the hands of the supreme court of Canada. Its ruling could set a precedent for similar cases in the future.
At the heart of the battle is the legal and ethical question of whether doctors can overrule a family's wishes in determining when to end treatment. As devout Muslims, Rasouli's family opposes treatment that would hasten death. Rasouli left no living will, and that complicates matters, says Mark Handelman, a lawyer in Toronto: "The first law is the previously expressed wish of the patient."
Consciousness test
What role can science play in determining whether Rasouli is in fact aware of his surroundings? The problem is that telling the difference between MCS and PVS is "an enormously difficult thing", says Adrian Owen of the University of Western Ontario in London.
Behavioural tests used by hospitals can be unreliable because someone who appears vegetative most of the time may in fact be minimally conscious, albeit showing signs of awareness only intermittently. A study in 2009 using a revised version of standard behavioural tests found that 40 per cent of patients diagnosed as in a vegetative state were actually minimally conscious.
A study by Owen's group in 2006 also highlighted the issue. The team developed a test in which apparently unconscious patients were told to imagine themselves either playing tennis or navigating their house, while doctors scanned their brain using fMRI. About 20 per cent of the supposedly vegetative cases that the group scanned were able to answer questions by imagining moving either their fingers or their toes for "yes" or "no". That does not mean the other 80 per cent are unconscious, he says: it is possible that the scans were just not refined enough to detect consciousness in some cases.
The problem goes the other way as well, he says. Some people who show signs of behavioural consciousness ? such as responding in some way to their family ? show no conscious brain activity in the scanner.
Costly scans
Since these studies, the use of fMRI to determine consciousness has started to take off, Owen says, with increasing numbers of doctors and families requesting him to test patients. The goal now is to bring down the cost so that the test can become routine. "We're giving these patients a voice, but it's a six-million-dollar voice," Owen says. In November, his group successfully detected consciousness using an EEG cap with only four electrodes; this equipment is closer to what most hospitals could afford, he says.
After Rasouli raised his finger, Owen was brought in to run the fMRI test on him. The results suggested a very low level of conscious brain activity, but were ultimately inconclusive.
As for whether consciousness improves the likelihood of recovery, that is still unclear, Owen says. One study has found a correlation between the ability to perform complex mental tasks and the chances of improvement (Brain, doi.org/cfch2d). However, the researchers could have just been detecting the early signs of recovery, he says.
Having a better way to detect consciousness would probably affect medical decisions "at the gut level", says Jennifer Chandler, a bioethicist at the University of Ottawa in Canada. But the basic problem ultimately remains: if a person has some awareness of their surroundings but little chance of improving, is it better to keep them alive, or kinder to let them die?
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