Has the RCP’s reluctance to issue guidance on fMRI scans for coma patients become indefensible?
In March 2020, the Royal College of Physicians (RCP) in the UK published national guidelines on the management of patients with prolonged disorders of consciousness (PDOC). Those guidelines updated their 2013 guidance, ‘particularly in relation to recent developments in assessment and management, and … changes in the law governing … the withdrawal of clinically assisted nutrition and hydration.’ The 2020 document’s primary focus is on patients who are not dying but who could live for many years with treatment and care.
Recently, a paper published in the journal Brain suggested that there may be as many as 25,000 people in the UK with PDOC, (though no national register currently exists[1]), and that 20 per cent of them have sufficient awareness to respond to commands in neuroimaging contexts even though there may be no visible evidence that they can. Detecting ‘covert consciousness’ in such patients could imply that they have the mental capacity to consent, or at least contribute to decisions about their own care, particularly their wishes relating to life-sustaining treatment such as clinically assisted nutrition and hydration (CANH). So, given the ethical and legal implications, it is clearly important to determine whether patients with PDOC are legally competent or at least able to express their views and feelings.
The paper’s authors – a neurologist, an imaging neuroscientist, and a lawyer-ethicist – review the 2020 RCP guidance in the light of research studies using functional MRI (fMRI) neuroimaging and/or bedside electrophysiology (EEG) techniques. The RCP guidance says that ‘while more advanced brain imaging and electrophysiology techniques have provided valuable insights into this patient group and will continue to provide an important focus for research…the evidence base has not yet reached a stage of development where these could be considered a part of routine clinical practice.’ The paper’s authors claim that significant advances made in the use of this technology in recent years mean that a sufficient evidence base does now exist, and they call for an urgent review of the guidance.
That 2020 RCP guidance drew substantially on the 2018 joint RCP and British Medical Association guidance concerning the use of CANH in adults who lack the capacity to consent, that requires doctors in such situations to make decisions based on the perceived ‘best interests’ of the patient. In doing so, they must take account of any previously expressed wishes of the patient, as well as the testimony of friends and family members. Evidence that a patient, who apparently lacks capacity but who can be shown to understand and respond to questions about their ongoing treatment using sophisticated fMRI or EEG techniques, would be ‘game-changing.’
The 2005 Mental Capacity Act (MCA) requires that ‘all practicable steps’ to support a person’s capacity to make, or contribute to making, relevant decisions be taken. The question is: are fMRI studies ‘practicable’? The RCP guidance argues that they are expensive, time-consuming, and difficult to interpret. The prognostic significance of covert responses may be unclear, and unlikely to influence clinical management in most cases, it claims.
However, the American Academy of Neurology (AAN) guidance, though it concurs in many respects with the RCP guidance, differs in one important aspect. It formally recommends fMRI or advanced electrophysiological testing in certain circumstances ‘where there is continued ambiguity regarding evidence of conscious awareness despite serial neuro-behavioural assessments, or where confounders to a valid clinical diagnostic assessment are identified.’ Here, specialised fMRI or electrophysiological studies may be used to seek ‘awareness not identified on neuro-behavioural assessment that might prompt consideration of an alternative diagnosis.’
The AAN guidance also recommends that in cases where a discrepancy emerges – clinical examination showing no evidence of consciousness but fMRI or electrophysiological testing implying preserved conscious awareness – patient management be altered (Recommendation 2f). Here, frequent neuro-behavioural re-evaluations may be conducted, and decisions to reduce rehabilitation treatment (for example, by discontinuing CANH or other life-sustaining treatment) may be delayed.
The point is this: patients without clinical evidence of awareness may have positive findings using other modalities (such as fMRI or electrophysiological studies), and these findings may prompt a change in diagnosis and/or clinical management. In one study, 32 per cent of patients diagnosed as unresponsive on clinical grounds showed brain activity compatible with (minimal) consciousness on at least one functional neuroimaging test, and 69 per cent of these subsequently recovered consciousness. A 2016 meta-analysis of 37 studies involving more than a thousand patients revealed 20 per cent to be covertly aware, implying that ‘some tens of thousands of patients worldwide have been erroneously assumed to be ‘awake but unaware’, sometimes for decades at a time.’ These results are hardly insignificant and suggest that the RCP guidance is both unduly pessimistic and ripe for review. As to expense, another of the RCP’s objections, in most cases, the benefit of assessing PDOC patients with investigational neuroimaging would outweigh the costs. In any case, as the paper points out, costs would normally be the concern of NICE, not the RCP.
To withhold fMRI scanning from covertly conscious patients presumes their lack of capacity and rejects any possibility that some level of residual capacity might be found – the position taken by the RCP in their 2020 guidance. If life-preserving treatment in the form of CANH is then withdrawn, it is possible the patient may be aware whilst being dehydrated and sedated to death.
This is not only unethical but also illegal. In determining what is in an (incompetent) patient’s best interests, the 2005 MCA requires the decision-maker to consider ‘so far as is reasonably ascertainable’ the person’s past and present wishes and feelings. Even if a patient is conscious but not competent, their wishes and feelings are nevertheless relevant. To withhold fMRI scanning is to deprive a covertly aware patient of the means whereby they might participate in ‘best interests’ decisions being made about them. Functional MRI scanning potentially brings that patient’s present wishes and feelings within the realm of the ‘reasonably ascertainable.’
Moreover, the withdrawal of life-sustaining treatment and care from patients who, if scanned and found conscious, would have wanted to have their treatment and care continued, may breach their right to life under legislation related to human rights and discrimination on the grounds of disability.
The paper concludes: ‘[The RCP’s] views on the value of neuroimaging and EEG in PDOC merit urgent reconsideration. Whilst research into this area is continuing apace, we believe there is already sufficient evidence to warrant a revision of the UK guidance so as to bring it into closer alignment with the US guidance.’
We would add that the clinical, ethical, and legal reasons to do so are compelling.
[1] A UK register of patients in PDOC was first recommended in RCPs PDOC National Clinical Guidelines (p25) in 2013 and is still awaited.
Leave a Reply
Want to join the discussion?Feel free to contribute!