Recent studies using functional magnetic resonance imaging of patients in a vegetative state have raised the possibility that such patients retain some degree of consciousness. In this paper, the ethical implications of such findings are outlined, in particular in relation to decisions about withdrawing life-sustaining treatment. It is sometimes assumed that if there is evidence of consciousness, treatment should not be withdrawn. But, paradoxically, the discovery of consciousness in very severely brain-damaged patients may provide more reason to let them die. Although functional neuroimaging is likely to play an increasing role in the assessment of patients in a vegetative state, caution is needed in the interpretation of neuroimaging findings.
This paper assesses the possible effects on decision making about the withdrawal of life-sustaining treatment if fMRI suggests that a patient in VS has some level of consciousness. It focuses on the principles set out in the Mental Capacity Act 2005 (UK) (which has come into force since the case mentioned above),5 the Mental Capacity Act Code of Practice (CoP)6 and the common law.
Brain imaging has allowed a man who was previously considered unconscious to answer a series of yes-or-no questions. The study, published this week in the New England Journal of Medicine1, challenges clinicians' definition of consciousness and provides an unprecedented opportunity to communicate with those who show no outward signs of awareness.
Background The differential diagnosis of disorders of consciousness is challenging. The rate of misdiagnosis is approximately 40%, and new methods are required to complement bedside testing, particularly if the patient's capacity to show behavioral signs of awareness is diminished. Conclusions These results show that a small proportion of patients in a vegetative or minimally conscious state have brain activation reflecting some awareness and cognition. Careful clinical examination will result in reclassification of the state of consciousness in some of these patients. This technique may be useful in establishing basic communication with patients who appear to be unresponsive.