In their review, Kondziella et al. have described the neuroscientific basis of coma, the spectrum of disorders of consciousness which may occur following severe brain injury (SBI) and ways to detect and stimulate the recovery of consciousness [11]. These disorders of consciousness may form a continuum and fluctuate over time. Coma and disorders of consciousness are intimately related to queries of value of life. One of the greatest challenges clinicians face in the intensive care unit (ICU) is to decide if it is appropriate to initiate ‘end-of-life’ care with withdrawal of active measures in patients following severe brain injury.

Kondziella et al. argue that premature end-of-life care should be avoided. If a meaningful physical and cognitive recovery is very likely to occur, a strong case can be made for this decision [11]. However, if the patient will remain severely disabled with unresponsive wakefulness syndrome (UWS; formerly known as the vegetative state), minimally conscious state (MCS) or cognitive motor dissociation (CMD) or covert consciousness, we submit that the ethical decision would be to provide ‘end-of-life’ or palliative care at an early stage, before these states become chronic.

This approach is anathema to individuals or societies who believe that life must be preserved in all circumstances. Physicians and families who decide to continue active treatment would also argue that there is also the possibility that patients with severe brain injury and ongoing coma may improve in the months following the injury, and not remain severely disabled or ‘vegetative’, and that techniques and drugs to stimulate consciousness may also improve the outcome. This is the crux of the problem. Which patient will improve and by how much? How certain are prognoses?

The patient’s age, general health, co-morbidities and their level of frailty should all be considered for prognostication. Reversible factors such as sedatives, muscle relaxants, electrolyte disturbances, fever, sepsis, anaemia, seizures and multi-organ failure may complicate or delay this decision-making. Prediction of outcome is an inexact science but becomes increasingly accurate the more time has elapsed from the acute brain injury.

For the patient in a prolonged coma following a severe brain injury, there is often instability in the first 7 to 10 days of ICU care. If the brain injury is severe clinically and on investigations such as computed tomography (CT), magnetic resonance imaging (MRI), somatosensory evoked potentials (SSEP), and electroencephalography (EEG), and the patient is showing no sign of neurological recovery, when reversible factors have been corrected, a decision may be made that further active treatment is futile and ‘end-of-life’ or palliative care is initiated. This decision becomes clearer when the pupils are dilated and unreactive bilaterally.

If the patient survives the first week to 10 days of instability, they frequently become clinically more stable but remain in a coma. They may require a tracheostomy to wean off the ventilator. The patient may then transition to a ward setting depending on the level of staffing and facilities. Improved diagnostic accuracy of coma becomes more achievable during this period. In some settings, the patient may stay in an ICU environment much longer because there is lack of a stepdown ward environment. The decision for tracheostomy is an important inflexion point toward ongoing active care versus palliation versus end-of-life care.

The detection of cognitive motor dissociation (CMD) has heightened the ethical dilemmas of decision-making. Claassen et al. describe the clinically unresponsive patients who may have brain activation on a quantitative EEG in response to spoken commands [2]. It should also be noted that these EEG changes may not represent comprehension or awareness. This was a relatively small series of 104 patients and only 15% of patients were responsive to verbal command as seen on EEG monitoring. Of these, 44% recovered to a Glasgow Outcome Score-Extended (GOSE) of 4 and above at 12 months. Level 4 on GOSE indicates that the patient needs partial assistance in activities of daily living and that there is some degree of independence [16]. Multi-centre studies with greater patient numbers are necessary to validate these preliminary findings [2]. Egbebike et al. have recently published a larger study of 193 patients [3]. At 12 months, 28 (15%) had a GOSE of 4 or above. CMD was seen in 27 (14%) of patients and was an independent predictor of shorter time to good recovery. Although this quantitative EEG test has yet to become a routine bedside test in ICU practice, it is worth considering when a decision is whether to withdraw care or palliate the patient. Functional MRI (fMRI) may also be used to detect CMD, but this is not usually practicable in an acute ICU setting.

Judging what might be perceived as acceptable levels of disability is also vexed [6]. A measure such as the GOSE may not accord with the patient’s own perception and acceptance of their level of disability. Retel Helmrich et al. have described patients following severe TBI who are severely disabled on GOSE but rate their well-being higher than the GOSE would suggest [9].

Whilst the detection of CMD, where it is available, will affect decision making, it is tragic when the end result of the brain injury is a severely disabled patient with persisting UWS, MCS or who is in a perpetual state of CMD. For those who do survive in a coma beyond the acute ICU phase, it is important to determine which patients have signs of CMD using the various techniques outlined by Kondziella et al. [11]. These patients may benefit from more active therapy than those without any sign of consciousness.

The ethics and moral dilemmas of disorders of consciousness have been extensively explored in the medical literature [5,6,7,8, 17,18,19,20]. Young and Edlow advocate for an ethical framework for the responsible use of emerging neurotechnologies for the diagnosis of covert consciousness and present four guiding ethical principles for the use of these neurotechnologies [19]. Fins argues patients have a right to die if there is no hope but that they have a right to care if they might benefit from coming advances in neuroscience [5]. Kondziella et al. have also provided an extensive list of pharmaceutical, electrical and other methods to stimulate levels of consciousness [11]. These are generally underutilised but have the potential to improve the patient’s level of functionality and quality of life.

Improved tools for prognostication in the acute phase of care are sorely needed. Prognostication of medical outcomes may improve in the future by using machine learning programmes [12], whilst the independent value of respective outcomes must be assigned by humans [13]. After any medical prognostication, the decision to continue with active management requires value assessments. The goal of the treatment of patients with severe brain injury is to achieve recovery with a good quality of life, which is a value-laden term. The decision of what constitutes a ‘favourable outcome’ is problematic [21] and even if this is decided, a remaining problem is to evaluate whether some outcomes might be worse than death. Hidden values can affect assessment and any ethical decision must reveal value-judgements transparently [4]. Important factors to consider are primarily first-person perspectives but also societal, legal, ethical, religious and family expectations. Deciding what degree of disability the patient is prepared to live with is made somewhat easier if the patient has made their goals and wishes clear prior to the brain injury, preferably in the form of an Advanced Care Directive. ‘Quality of life’ is ultimately a subjective and volatile experience. Even an advanced directive may be misleading if formulated before the patient entered the condition at hand; altered priorities are common when existential conditions change [4, 10, 15].

We argue that persisting UWS, MCS or a perpetual state of CMD are unlikely to be associated with value for individuals who do not have conscious sensations. Continued treatment could then not possibly increase value and would be futile from a value perspective. Moreover, acute and prolonged treatment of patients with severe TBI requires extensive resources for intensive care, rehabilitation and long-term care, which, amongst four bioethical principles, raises issues of justice [1]. A degree of rationing of care may be required depending on available resources in the health system [14]. Importantly, it is unlikely that the cost–benefit of extensive treatment without a perspective of regaining consciousness would be acceptable from any perspective of equality or justice. Our underlying belief is that consciousness is fundamental for value of life. This belief disagrees with a sanctity of life doctrine; thus, we also argue that the principle of justice mandates timely limitation of treatment in certain cases of severe TBI since not all possible patients could possibly be offered extensive care in the face of a grim prognosis after TBI.

We must act responsibly and pragmatically despite uncertainty of prognoses, uncertainty of the nature of consciousness and uncertainty of its moral connotations. Decisions should be transparent and equitable. Whilst clinicians should avoid nihilism, they should present realistic prognostic information to families and strive for evidence-based humane decision-making. This decision is best achieved when a team of intensivists, medical and surgical specialists and nurses all confer to reach a consensus view to discuss with the family or the lawful surrogate decision maker.