‘When I use a word,’ Humpty Dumpty said, ‘it means just what I choose it to mean—neither more nor less’. ‘The question is,’ said Alice, ‘whether you can make words mean so many different things’. (Carroll L 1872. Alice through the looking glass)

Palliative sedation is a term used to describe the use of sedative drugs in dying patients to induce a state of decreased or absent awareness (unconsciousness) in order to relieve intolerable suffering from refractory symptoms.1 ,2 Perhaps, for many of us, this conjures up an image of an agitated patient who is rendered unconscious in the last hours of life as a result of the need for repeated doses of sedative drugs.

However, in the literature, ‘palliative sedation’ is used more broadly, sometimes as an umbrella term for all levels and patterns of sedation in those close to death.3 ,4 For example, a systematic review about palliative sedation includes a report of sedatives prescribed to 68/102 patients at some point in the last week of life,5 for whom ‘sublingual lorazepam tablets and clonazepam drops were commonly used and efficacious’. (This is the source of the figure quoted elsewhere that up to 67% of dying patients may need palliative sedation.)

Perhaps the ultimate absurdity in relation to the use of the term is an article about night sedation with intravenous midazolam in two patients with cancer for 4 weeks and 4 months, respectively, but describing it as ‘long-term intermittent palliative sedation’.6 The refractory insomnia (±delirium) was relieved by the night sedation and daytime pain scores reduced from 8–10/10 to 2–3/10.

It is surely the time to abandon the term ‘palliative sedation’ as essentially meaningless and potentially misleading. Better to speak simply of ‘sedation’, qualified by brief, intermittent or continuous, and light, moderate or deep. It is thus heartening to see a shift in the research literature towards the use of the unambiguous term ‘continuous deep sedation at the end of life (CDS)’.3

Unlike other forms of sedation, CDS is ethically contentious because it permanently ends ‘biographical’ life. Accordingly, guidelines typically limit CDS to ‘the last few hours or days of life’ or ‘a prognosis of less than 1–2 weeks’.7 Further, despite claims to the contrary,8 unless of short duration, CDS will also inevitably shorten ‘biological’ life because it suppresses brainstem vital centres.9 In addition, guidelines tend to encourage a ‘one size fits all’ mentality. This is of particular concern because delirium (acute confusional state) is the commonest indication for sedation in the dying, and midazolam (which tends to exacerbate delirium) is generally stated to be the drug of first choice.10

As in medical practice generally, interventions must be justified by necessity (distress/suffering) and must be proportionate (only use a sledge-hammer if nothing else works). Ethically, given that it ends ‘biographical life’, CDS must be regarded as an exceptional ‘last resort’ measure, and not ‘normal’ or ‘routine’ practice. At one Belgium palliative care unit, the incidence of CDS fell from 7% to 3% over 6 years as a result of improved symptom management and a team approach to decision-making.11 In contrast, over the last 10–15 years, the nationwide incidence of CDS in non-sudden deaths has increased from 8% to 12%.12 This too is cause for concern.

Further, in Belgium and the Netherlands (where euthanasia is legal), rapid inducement of deep unconsciousness is typical, partly because of pressure from relatives to hasten death.13 Indeed, CDS is sometimes organised like euthanasia, with a family farewell before the patient is rendered permanently unconscious.13

In contrast, in the UK, clinical practice tends to reflect the guidelines of the European Association for Palliative Care,2 with the emphasis on titrating doses proportionately against symptoms, maintaining consciousness if at all possible.13 The comment of a UK palliative care doctor reflects this:I haven't given anyone continuous sedation: there have been lots of patients who have become agitated at the end of their lives and in those cases it's appropriate to give medications to relieve that agitation and that restlessness. So we are giving drugs that do have sedative effects but the aim is not necessarily to sedate, the aim is to relieve that agitation and restlessness and make them more comfortable.14

Although CDS for more than a few hours will have a progressively increasing life-shortening effect, it is theoretically possible to distinguish between CDS and euthanasia (table 1). However, if not imminently dying, CDS is indistinguishable from ‘slow euthanasia’ even if clinically assisted hydration is provided.

It should be noted that in the Netherlands some doctors actively encourage patients to opt for CDS rather than euthanasia because it is associated with less bureaucracy.13–15 This raises the question: can the practice of CDS lead to ‘mission creep’? The answer is yes:

• There are reports of CDS which can be described only as non-voluntary (unrequested) euthanasia.16

• The Norwegian Medical Association recently widened its guidelines from ‘palliative sedation for the dying’ (prognosis of <2 weeks) to ‘palliative sedation at the end of life’ (prognosis unstated).17

• In the USA, it has been proposed that the ‘last resort’ criterion should be dropped, and CDS allowed for any patient with a prognosis of <6 months.18

• France has legalised CDS such that, in practice, it is likely to become a specific substitute for euthanasia.19

Taking all these into account, I suggest that the key ‘take-home’ messages are:

• Because of Humpty-Dumpty usage, the term ‘palliative sedation’ should be abandoned.

• Given quality palliative care, CDS as the primary aim of treatment should only rarely be necessary.

• Abuse of CDS occurs and seems likely to increase.