The use of assisted hydration (AH) at the end of life has long been the subject of controversy. Practice is highly varied between countries and cultures (Raijmakers et al, 2011a), and it may be that social and religious factors play a pivotal role. For example, beliefs about the sanctity of life in Orthodox Jewish or Catholic-majority countries, or about the importance of food and drink in some East Asian cultures, may increase the use of AH at the end of life (Musgrave et al, 1996; Chiu et al, 2004; Morita et al, 2006).
The frequency of provision of fluids for dying patients in a community setting is not known. A Dutch study (Lokker et al, 2019) demonstrated large differences in rates of administration of AH for patients in hospital and hospice (74% and 4%, respectively). What might explain these differences? AH may be considered conventional practice in hospital, or it may be provided because dying is not recognised promptly, or because conversations about stopping parenteral fluids are considered to be too difficult. In hospice settings, AH may be indicated on occasion, but may not be prescribed due to it not being perceived as standard practice.
Inconclusive evidence about impact
Another factor contributing to the widespread variability in practice is the uncertainty about its impact. A recent systematic review of 15 studies found insufficient evidence to draw conclusions about the effect of AH on survival or symptoms for people in the last week of life (Kingdon et al, 2021). One study had intriguing results, suggesting a possible link between the provision of AH and a small survival benefit. However, this feasibility study was too small to generate definitive findings (Davies et al, 2018).
Qualitative studies provide inconsistent insights. In one, patient and family participants attached universally positive meanings to AH, feeling that it brought ‘hope’ and ‘comfort’ (Cohen et al, 2012); in another, most participants (bereaved relatives) recognised that reduction in oral intake towards the end of life is normal, and many had concerns about the continuation of AH (Raijmakers et al, 2013). Intravenous and subcutaneous fluids have been compared only in two very small studies (O'Keeffe and Lavan, 1996; Dasgupta et al, 2000), representing yet another uncertainty regarding this area of practice.
Importantly, lack of evidence does not equate to lack of benefit. A definitive, well-powered study is urgently needed. In the meantime, and in the absence of evidence, the resulting void is filled by our beliefs, biases and personal experiences.
Challenging clinical dogma
The palliative care approach often entails considering reducing or stopping unnecessary or burdensome treatments (National Institute for Health and Care Excellence (NICE), 2013). However, it is important to avoid developing a rigid view that AH is never helpful in last days of life care. If we ignore the nuances of each patient's unique situation, or if we are already formulating counter-arguments when families express concern about reduced drinking, then we miss the chance to truly listen. Provision of person-centred care necessitates avoidance of blanket policies and dogmatic thinking.
Most people dying with or without fluids appear to die comfortably. For those with progressive disease, the reduction of interest in food and fluid is typically gradual, reflecting the body's reducing needs. However, in contexts with sudden changes of condition, profound dehydration and thirst may develop, and these are unlikely to be alleviated by mouth care alone. For example, a person who has suffered a major stroke may not be able to communicate their sense of thirst; rapid-onset hypercalcaemia may present similar challenges. In such cases, it is risky to assume AH will be unhelpful and unwise to dismiss family concerns about dehydration.
The situation is no different for people dying at home. However, despite studies demonstrating that it is a safe and feasible treatment in a community setting (Vidal et al, 2016; Coelho et al, 2020), dying outside an inpatient environment tends to preclude access to AH. The District Nursing Manual of Clinical Procedures, for example, does not mention the possibility of considering subcutaneous hydration in the home (O'Brien, 2012). At present, inpatients apparently benefitting from AH as they approach the end of life tend to be faced with a stark choice: either continue to receive AH in an inpatient setting or be discharged without AH.
For services willing to consider provision of AH at home, several questions arise. Who will be clinically responsible for the prescription and the decision-making process? Who will review the continued clinical appropriateness and effectiveness of care? What equipment, supplies and nursing resources would be needed if this practice were to become more commonplace? And, importantly, what are the views of patients and their families in relation to receiving AH at home? The few community teams that do provide a home AH service should share their experiences, both to disseminate learning and to stimulate discussion about how these questions might best be answered.
Conversations with patients and families
The lack of evidence about the impact of AH creates uncertainty in clinical decision-making. In turn, this leads to wide variability in practice, without consistent models of how best to provide AH at home. Furthermore, there is little evidence evaluating patient or carer perspectives on AH provision (Raijmakers et al, 2011b; Pettifer et al, 2020), and even less evidence about their views on AH provision at home (Mercadante et al, 2005). How, then, can we discuss this thorny topic with dying patients and their families? NICE guidance (NICE, 2013) suggests that clinicians should routinely discuss the benefits and risks of AH with dying people and those close to them, without providing suggestions about what these might be. However, national audit data show that such conversations happen with fewer than one-in-three families of dying people in hospital (NHS Benchmarking Network, 2019). The frequency of such communication is unknown in community settings; does it, indeed, make sense to begin discussion about a treatment that may be logistically difficult to facilitate?
Further research is much needed. As we are discovering in an ongoing study evaluating health professionals' perspectives on AH, clinicians mostly default to delivering a gentle and sensitive explanation of the ‘accepted wisdom’ that AH is unlikely to help people who are dying and might cause harm. While this approach is valid in most circumstances, the first task is to explore concerns and actively listen, in order to really understand the perspectives and priorities of the patient and their family. In the absence of evidence-both relating to the impact of AH and to patients' views-shared decision-making is vital. Only once a mutual understanding is reached can we effectively navigate this emotive topic.