Use of Artificial Hydration at the End of Life: A Survey of Australian and New Zealand Palliative Medicine Doctors

Abstract

Background:

Dying is ubiquitous, yet the optimal management of hydration in the terminal phase is undetermined. Palliative care (PC) doctors' practices may act as a de facto measure of the benefits and burdens of artificial hydration (AH) use.

Objective:

To identify PC doctors' AH prescribing practices for imminently dying patients and possible influencing factors.

Methods:

An online survey of doctors belonging to the Australian and New Zealand Society of Palliative Medicine.

Results:

One hundred and thirty-six surveys were completed (30% response rate). AH use for patients in the prognosticated last week of life was low: 77% of respondents prescribed AH to 0–10% of patients and 3% of respondents prescribed to more than 20%. The most common reason for prescribing AH was palliation of family/patient concern rather than a physical symptom. The majority thought there was no effect of AH on survival, or on symptoms of fatigue (90%), reduced level of consciousness (88%), agitation (75%), nausea (69%), vomiting (68%), myoclonus (66%), thirst (65%), delirium (62%), cough (57%), or bowel obstruction (50%). AH was thought to worsen subcutaneous edema (94%), upper respiratory tract secretions (85%), ascites (73%), physical discomfort (72%), dyspnea (62%), and urinary symptoms (57%).

Conclusion:

PC doctors from Australia and New Zealand reported lower use of AH for dying patients compared to international counterparts. The study showed high concordance in respondents' opinions: most thought AH was unlikely to provide clinical benefit and might cause harm. Further studies are needed to determine best practice of AH use at the end of life.

Introduction

For more than 25 years, the issue of whether to use artificial hydration (AH) in patients receiving palliative care (PC) has generated worldwide debate regarding its ethics, legalities, and benefits versus burdens.^1,2

Publications quantifying AH use in PC patients are few in number; however, it is evident that it is a frequent practice worldwide, including in the imminently dying, particularly in acute care settings.^3–5 Arguments used on both sides of the PC hydration debate have been well documented in the literature^2,6–8; however, actual best practice is not defined because of a lack of rigorous scientific evidence.^9–11 Two published literature reviews on this topic have concluded that there is insufficient good quality evidence to inform definitive practice recommendations⁹; and that the effects of AH on comfort, symptoms, and length of survival seem limited in the last week of life and do not clearly outweigh the burdens.⁴ More recently, the effect of AH use in the last week of life was examined in a Swedish historical cohort study; it showed a significant association between AH administration and increased frequency of documented dyspnea.⁵

As a result of the equivocal evidence base, there is a wide variation by doctors in the hydration management of PC patients, influenced by factors such as the country's culture, the doctor's specialty, and the patient's care setting.^3,12,13 Because robust clinical studies involving PC patients are difficult to perform for a variety of ethical and methodological reasons,^14,15 it has been postulated that the opinions and practices of health professionals who care for greater numbers of terminally ill patients may act as a de facto measure of the benefits and burdens of AH use.^16–18 However, worldwide, there are very few studies that examine PC doctors' AH prescribing practices and possible influencing factors: two small-scale surveys from Canada and Australia (11 and 4 participants, respectively)^19,20; a survey from Japan that included 90 PC doctors, analyzed in three separate publications^3,17,18; and a survey of 238 PC doctors from Latin America (LA).¹⁶

The aim of this study was to identify Australian and New Zealand (ANZ) PC doctors' AH prescribing practices for patients specifically in their prognosticated last week of life, and factors that may influence these practices.

Methods

The cross-sectional study used an online, self-administered, anonymous survey targeting all members of the Australian and New Zealand Society of Palliative Medicine (ANZSPM). The Human Ethics Research Committee of the South Eastern Sydney Local Health District gave ethics approval for the study (HREC 15/158; 18/8/2015).

ANZSPM members are physicians who either practice or have an interest in palliative medicine. An e-mail invitation to participate was distributed in September 2015 and it included a link to the survey host site, Survey Monkey. The survey was open for five weeks and one e-mail reminder was sent.

The ad hoc survey comprised 17 questions, all, except one, were multiple choice or Likert item (5- or 6-point scale). Question design was influenced by relevant surveys of health professionals,^3,16–21 and from studies examining the benefits and burdens of AH and attitudes to the use of AH in PC patients.^{2,4,6,9–13,22–31} The survey was tested for face validity. The survey questions referred to patients in “the prognosticated last week of life.”

Data management and statistical analysis were performed using Survey Monkey and SPSS (Statistical Package for the Social Sciences) software. Unpaired chi-square tests were chosen to calculate the statistical significance of comparisons between data variables. A p value <0.05 was considered statistically significant.

Results

Response rate and participant characteristics

Of the 457 PC doctors invited to participate, 136 completed the survey (30% response rate). Completion was regarded to have occurred if the respondent answered the demographic questions, and the primary research question on the prescription of AH to patients in their prognosticated last week of life. The response rate for Australian members and New Zealand members was similar (29.3% vs. 31.4%); however, most respondents were Australian (75.7%, n = 103). The majority of respondents were female, had substantial PC experience, worked in a specialized PC service, and were located in a metropolitan region (Table 1).

Table 1.

Demographic Characteristics (n = 136)

Characteristic	% (n)
Gender
Female	62.5(85)
Years of palliative care experience
1–3	15.4 (21)
4–9	30.2 (41)
10–20	33.1 (45)
20+	21.3 (29)
Palliative care as a percentage of usual practice
0–20	5.2 (7)
21–50	5.9 (8)
51–75	8.8 (12)
76–100	79.4 (108)
Retired/nonclinical	0.7 (1)
Principal type of palliative care practice in past year
Palliative care unit	38.2 (52)
Consult service	36.8 (50)
Community service	11.7 (16)
Mixed types of PC practice	5.9 (8)
General practice	3.7 (5)
Other	3.0 (4)
Retired	0.7 (1)
Location
Australia	75.9 (103)
New Zealand	24.1 (33)
Region
Metropolitan	72.8 (99)
Regional	24.3 (33)
Rural	2.9 (4)

PC, palliative care.

Prescribing practices

The survey's responses showed that in the past year, the prescription of AH to patients in their prognosticated last week of life was low (Fig. 1). There was no statistical difference between prescribing AH based on gender, country, percentage of PC work, type of PC work, or region (data not shown).

FIG. 1.

Percentage use of AH in patients in their prognosticated last week of life. AH, artificial hydration.

In total, 125 respondents indicated a volume range they would most often use if prescribing AH during the last week of life: 66.4% (n = 83) chose 501–1000 mL per 24 hours, 32.8% (n = 41) chose ≤500 mL, and 0.8% (n = 1) chose 1001–1500 mL. Of those who indicated their preferred route for AH, 97.6% (n = 122) chose the subcutaneous route, 2.4% (n = 4) preferred the IV route, and none chose nasogastric tube or rectal routes. There were no statistical differences between the ANZ doctors for prescribed volumes (p = 0.26) or routes of administration (p = 0.24).

Institutional guidelines

Seventy percent (n = 95) of respondents indicated that there was no institutional guideline regarding AH use, 14% (n = 19) reported a guideline, and 16% (n = 22) were unsure. Use of institutional guidelines for AH appeared to be more prevalent in New Zealand than in Australia (respectively, 51.5% vs. 75.7% of respondents indicated there was no guideline, p = 0.005).

Reasons for prescribing AH

Respondents were asked to rank their three most common reasons for prescribing AH to imminently dying patients from a list of 20 options. A total of 307 responses were received. The most common primary reason was a family member's concern (45.1%, n = 50). Other reasons cited included patient's concern (15.6%, n = 48), possibility of physical symptom alleviation (11.7%, n = 36), hypercalcemia (10.4%, n = 32), sensation of thirst (9.8%, n = 30), opioid toxicity (5.9%, n = 18), delirium (5.2%, n = 16) and dehydration (4.2%, n = 13).

Opinions of AH

There was strong concordance in opinions regarding AH use in end-of-life care (EoLC) (Table 2).

Table 2.

Opinions Regarding Artificial Hydration During End-of-Life Care (n = 135)

Statement	% (n)
AH is a minimum standard of care in EoLC Agreed or strongly agreed	3.0 (4)
Neutral	7.0 (9)
Disagreed or strongly disagreed	90.0 (122)
Withholding AH often shortens patient survival in EoLC
Agreed or strongly agreed	4.4 (6)
Neutral	10.4 (14)
Disagreed or strongly disagreed	85.2 (115)
Withholding AH during EoLC may lead to criticism from colleagues
Agreed or strongly agreed	22.2 (30)
Neutral	22.2 (30)
Disagreed or strongly disagreed	55.6 (75)
Withholding AH during EoLC may lead to loss of patient/family trust
Agreed or strongly agreed	27.7 (37)
Neutral	18.5 (25)
Disagreed or strongly disagreed	54.1 (73)
AH is effective for symptom palliation during EoLC
Agreed or strongly agreed	7.4 (10)
Neutral	26.0 (35)
Disagreed or strongly disagreed	66.6 (90)
Patients have the right to refuse AH during EoLC
Agreed or strongly agreed	97.1 (131)
Neutral	0.7 (1)
Disagreed or strongly disagreed	2.2 (3)
Administering AH can improve the nonphysical (psychological/emotional) quality of life of an end-of-life patient/family
Agreed or strongly agreed	46.7 (63)
Neutral	28.2 (38)
Disagreed or strongly disagreed	25.2 (34)
Reduced oral intake in the terminal stages of life is a natural process
Agreed or strongly agreed	97.6 (132)
Neutral	0.7 (1)
Disagreed or strongly disagreed	1.5 (2)

Totals add to n = 135 because of incomplete data.

AH, artificial hydration; EoLC, end-of-life care.

There were three questions in our survey that explored opinions on the effect of AH on survival. The first question, “Withholding AH often shortens patient survival during EoLC,” was disagreed with by 85.2% (n = 115) of respondents. For the second question, “In the prognosticated last week of a patient's, life do you think giving AH to a patient usually prolongs their life?,” nearly 75% (74.8%, n = 101) of respondents thought AH could not prolong life, 12.6% (n = 17) said it could, and 12.6% (n = 17) were undecided. Of the 17 respondents who thought life was usually prolonged, 18% (n = 3) believed it might be by hours, 82% (n = 14) by days, and none by weeks. No New Zealand doctor agreed with either of the above questions, which produced a statistical difference between the two countries' responses (p < 0.001 and p = 0.006). For the third question, “In the prognosticated last week of life, do you think giving AH can shorten the life of a patient?,” 51.1% (n = 69) of respondents thought AH could not shorten life, 30.4% (n = 41) thought it could, and 18.5% (n = 25) were undecided; there were no statistical differences between the two countries' responses for this question.

One question was designed to indirectly assess overall perceived benefit or burden of AH, “How likely are you to refuse AH in your own EoLC (last 1–2 weeks)?” Eighty three percent (82.9%, n = 112) of respondents indicated they were “most likely” or “likely” to refuse, 12% (11.9%, n = 16) were neutral, and 5.2% (n = 7) were unlikely or most unlikely to refuse; and there was no statistical difference between the two countries' responses.

Perceived effects of AH

Respondents were asked their opinions on the effect, in the last week of life, of giving AH on 21 different symptoms or signs (Fig. 2). Not all respondents completed an answer for each variable (range = 127–132). Only three symptoms were thought by the majority to be improved by AH: patient or family concern at patient's lack of oral intake (78%, n = 103), symptoms of hypercalcemia (71.6%, n = 93), and symptoms of dehydration (60.2%, n = 77).

FIG. 2.

Opinions on the effect of AH on symptoms in the last week of life (n = 127–132).

The majority of respondents thought that there was no effect of AH on fatigue (90.1%, n = 118), reduced level of consciousness (87.7%, n = 114), agitation (75.2%, n = 97), nausea (68.5%, n = 87), vomiting (68.5%, n = 87), myoclonus (66.2%, n = 86), thirst (65.4%, n = 85), delirium (61.5%, n = 80), cough (56.9%, n = 74), or symptoms of bowel obstruction (50.4%, n = 66). Approximately equal numbers responded that AH had no effect or would worsen a pleural effusion (47.3% [n = 62] vs. 45% [n = 59], respectively).

AH was thought to worsen or markedly worsen subcutaneous edema (93.9%, n = 124), upper respiratory tract secretions (84.7%, n = 111), family concern due to signs of fluid overload in the patient (74.6%, n = 97), ascites (73.1%, n = 95), physical discomfort secondary to attachment to AH apparatus (71.5%, n = 93), dyspnea (62.3%, n = 81), and urinary symptoms such as incontinence or need for a catheter (57.3%, n = 75).

Discussion

To our knowledge, this is the first quantitative study to investigate the AH prescribing practices of PC doctors from Australia or New Zealand.

The low levels of AH use found in this study are in keeping with previous studies that show a reluctant attitude to AH prescribing by PC doctors.¹² In fact, our study shows that surveyed ANZ PC doctors had lower rates of AH use in the imminently dying than most documented international counterparts. In Taiwan, PC doctors believed that ongoing use of AH two days before death was morally appropriate in 85% of their patients.²¹ In Japan, doctors in a PC unit prescribed AH to 44% of cancer patients in their final week.³² Studies of Canadian PC units showed that the majority of their terminally ill cancer patients received AH, often until death.^24,33–35 A survey of PC doctors from 18 LA countries found high rates of AH prescription: 60% of respondents prescribed AH to 40–100% of patients during the last weeks of life, and in this group of countries, only 1.3% responded that they never prescribe AH¹⁶ compared with 8% of PC doctors in our ANZ survey. ANZ PC doctors' AH prescribing rates appear to be more consistent with the conventional/traditional hospice philosophy, which is still followed in the United States, where hospice patients do not commonly receive AH.²⁵ However, it should be noted that our respondents' low prescribing rates were independent of care location.

Why surveyed ANZ PC doctors have such low rates of AH prescription in dying patients is difficult to postulate. Other authors have explored possible sociocultural and religious factors to account for a country's positive or negative characterization of AH use in the terminally ill.^21,26 We did not investigate these factors in our study; however it is possible to infer from the high concordance of responses that a contribution to the low rates of AH prescription by the surveyed doctors is their opinion that there is either nil effect or a negative effect on most physical symptoms with the use of AH.

Comparison to surveys of PC doctors from LA and Japan shows that there is a diversity of opinions as to the perceived effects of AH.^16,17 Our study found that a very low number of ANZ respondents thought fatigue could be improved by AH use compared to the LA and Japanese respondents (1.5% vs. 33% vs. 13%, respectively). Higher percentages of LA PC doctors, compared to Japanese and ANZ doctors, thought delirium and thirst could be improved (respectively, 59% vs. 18% vs. 28%; and 52% vs. 21% vs. 29%). Twenty-five percent of LA PC doctors versus 82% of Japanese agreed that withholding AH alleviated the burden of urination. When surveyed on the effect of AH on nausea and vomiting, 12% of LA PC doctors agreed that withholding AH prevented these symptoms, versus 89% from Japan who agreed that withholding AH alleviated them. Japanese PC doctors also had strong beliefs that withholding AH alleviated cough/sputum/dyspnea (91% agreement). In comparison, the majority of ANZ respondents thought that giving AH had no effect on nausea, vomiting, and cough, and worsened sputum, dyspnea, and urinary symptoms.

Although 60% of ANZ respondents thought AH could improve “symptoms of dehydration” during the last week of life, it is of note that only 4.2% chose dehydration as a reason for prescribing AH. One could postulate this indicates that the respondents did not consider dehydration to be burdensome to the imminently dying. Also noteworthy, in order to compare to international results, words or phrases that lacked definition and clinical clarity were included in this survey, for example, “dehydration” and “possibility of physical symptom alleviation.” There were higher responses for the less-specific conditions, such as 60% responded that AH could improve “symptoms of dehydration,” whereas minorities thought commonly accepted symptoms of dehydration such as fatigue, thirst, and delirium^10,36 were improved by AH. This may reflect an appreciation by respondents for the multifactorial causes of fatigue, thirst, and so on, and an understanding that these symptoms are not always related to syndromes, for example, dehydration or hypercalcemia, and therefore AH will not alleviate them.

Other factors influencing low prescribing rates may include strong beliefs by our respondents that reduced oral intake in the terminal stages is a natural process, and that giving or withholding AH does not affect survival. Surveys from Japan and LA have shown support for statements that indicate AH is a minimum standard of care, or AH is effective for symptom palliation, predicted higher prescribing rates of AH,^3,16 whereas in this survey, with overall decreased rates of prescribing AH, respondents showed a negative attitude to similar statements. There was a low prevalence of institutional guidelines reported; therefore, it is unlikely that these influenced practice.

AH can be given through different routes, for which various advantages and disadvantages have been postulated.^6,27 Our survey found that those prescribing AH had a very strong preference for the subcutaneous route. This compares to PC doctors from Taiwan, Latin America, or Japan who had a strong preference for the IV route.^16,21,37 There is evidence that patients and family members feel AH hydration is more beneficial through the IV route,²⁸ and this may influence its preference in countries that have higher rates of AH use.

AH volumes prescribed by the ANZ respondents were generally less than those reported internationally. When AH was chosen to be given to a dying patient, 99% of our respondents elected to give ≤1000 mL per 24 hours, as opposed to LA respondents where 27% would prescribe >1 L daily.¹⁶ In Canada, the reported range was 200–2400 mL/day,¹⁹ and in Japanese PC units, the range of AH volumes given to patients with advanced cancer was 200–1400 mL/day.^32,37 Although there may be disagreement on optimal AH volumes, there was high concordance by PC doctors surveyed in Australia, New Zealand, Japan, and LA that patients have the right to refuse AH.^16,17

The influence of patient and family concern on prescribing AH was a recurrent finding in our results. These concerns have been postulated by other authors to be a function of multiple factors,²⁶ including that most PC patients and their relatives perceive benefits from AH.^11,12,22 Eating and drinking have a meaning that goes beyond providing physical nutrition and feelings of satiety and well-being; it can have great symbolism in terms of hope²² and a person's sense of self within their family, society, and culture. A large quantitative study of bereaved family members showed >70% had been distressed when faced with the situation of a terminally ill loved one being unable to eat or drink.³⁸ Studies have also shown that health professionals can be distressed by decisions regarding hydration therapy.^13,39 Thus the nonprovision or provision of AH may be a deeply emotive issue to family, patient, and staff, requiring sensitive and empathetic communication.

Several authors have found a patient and family's agreement to the provision or nonprovision of AH to be significantly influenced by a health professional's recommendation.^23,40 In contrast to other countries,¹⁶ there are no financial incentives to provide or not provide AH in Australia or New Zealand, and thus based on their highly concordant responses, the surveyed doctors' infrequent recommendation of AH use in the last week of life is presumably influenced by their perceptions of lack of benefit and possibility of harm. Most current evidence does support the view that AH is unlikely to be beneficial for the imminently dying PC patient.^13,31 However, our study also supports the international consensus that an individual patient's needs should always be holistically assessed, taking into account their current clinical and performance status, potential benefits, and burdens of treatment, their goals of care, and the patient's and family's wishes.^{10,11,16,26,36,41} Fulfilling this charter may require the judicious use of AH in the dying patient, with appropriate communication and education of the family and careful monitoring for adverse effects that may necessitate AH cessation.

Implications for research

The above discussion shows international diversity in practices and opinions of AH use by doctors frequently providing EoLC; recognition of this will hopefully stimulate further research into this area, particularly whether the accepted patterns of AH use in any given setting/country are really achieving the desired palliative benefit for an imminently dying patient. We suggest that future studies should be careful to use defined terms, which are clinically relevant and able to be appropriately interpreted.

Limitations

This study has several limitations; these include selection bias with no ability to describe nonresponders, and it is a nonvalidated survey and, in part, used proxy evaluation. Although the response rate is low, it is in keeping with other web-based surveys of physicians.^42,43 Another limitation is that if using AH in the dying is uncommon, then there may be a paucity of direct clinical experience as to its effects, and opinions are based on self-perpetuating unsubstantiated teaching.

Conclusion

In comparison to international studies, the ANZ PC doctors surveyed reported low usage of AH in the last week of life The doctors also had high concordance in opinions as to the effects of AH: the majority of respondents thought it was unlikely to provide benefit and might cause harm to imminently dying patients, but would prescribe if needed to alleviate the concerns of the family or patient. Our study adds new empirical evidence of AH prescribing practices to the scant worldwide body of knowledge in this highly debated area, and it is hoped that further research will ultimately bring clearer guidance to all health professionals managing this controversial and emotive issue.

Footnotes

Acknowledgments

The authors thank the ANZSPM members who completed the survey.

Author Disclosure Statement

No competing financial interests exist.

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