speak kindly to your comatose patient

At least ‘one quarter of people with brain injuries who seem unresponsive can hear things going on around them and might even be able to use brain-computer interfaces to communicate‘, according to a recent article in Nature. 1

It is not known how many patients there are in the UK with Prolonged (more than six months) Disorders of Consciousness (PDOC) following an acute brain injury, but it runs into the thousands.

In 2020, the Royal College of Physicians (RCP) published its updated national guidelines on the management of patients with PDOC. 2 The focus was on developments in assessment since their 2013 guidance. They concluded that, while there may be a place for functional magnetic resonance imaging (fMRI), Positron Emission Tomography (PET) scans, and sophisticated electroencephalograms (EEGs) in research, ‘they do not form part of the standard assessment battery’ and that diagnosis ‘rests on clinical observation of behaviours that may suggest awareness of self and the environment’. 3

Response to the guidance was swift. Scolding et al. took issue with the RCP’s rejection of the routine use of advanced imaging technology. They pointed to a 2016 systematic review and meta-analysis of studies involving over a thousand patients showing that about 20 per cent exhibited signs of awareness, implying that ‘some tens of thousands of patients worldwide have been erroneously assumed to be “awake but unaware”’. They concluded that, ‘given the clinical, ethical and legal importance of determining whether patients with prolonged disorders of consciousness are legally competent or at least able to express their views and feelings, the Royal College of Physicians’ guidelines requires urgent review’. 4

In August 2024, an article in the New England Journal of Medicine found that some patients ‘may perform cognitive tasks that are detected by fMRI and EEG’ – a phenomenon known as Cognitive Motor Dissociation (CMD). 5

Two hundred and forty-one of the participants had no observable response to spoken commands, but 112 did. Using one or both of fMRI and EEG techniques, CMD was discovered in 60 of the 241 (25 per cent) and in 43 of the 112 (38 per cent). That is, approximately one in four participants without an observable response to verbal commands performed a cognitive task on fMRI and/or EEG, and one in three participants with an observable response to commands.

As reported in Nature, the 25 per cent of outwardly unresponsive people who showed brain activity tended to be younger than those who did not, to have suffered brain injuries that were from physical trauma, and to have been living with their injuries for longer than the others.

Further research is clearly needed, but this is the first large, multi-centred, multi-national investigation of its kind. It supports Scolding’s call for a review of RCP guidance.

Nevertheless, it is clear that some brain-injured patients, previously thought to be unconscious, may be conscious and able to communicate their feelings about what is in their own ‘best interests,’ which in turn will affect decisions made by their family and medical teams caring for them. If it can be shown that they have capacity, the decision-making process around ongoing care will radically change. As a result, it is likely that fewer PDOC patients will have clinically assisted nutrition and hydration withdrawn and die by dehydration and sedation.

Showing that some patients considered cortically dead can communicate meaningfully should drive investment and increase access to functional imaging and electrophysiology techniques, currently only available in specialised units.

This evidence calls for a review of the RCP’s guidance lest we inadvertently dehydrate to death those who can hear us make that bedside decision. And speak kindly; there is a higher chance than previously recognised that your comatose patient is listening