Alternative forms of hydration in patients with cancer in the last days of life: study protocol for a randomised controlled trial

Medically assisted hydration for adults receiving palliative care

BACKGROUND

Many people receiving palliative care have reduced oral intake during their illness, and particularly at the end of their life. Management of this can include the provision of medically assisted hydration (MAH) with the aim of improving their quality of life (QoL), prolonging their life, or both. This is an updated version of the original Cochrane Review published in Issue 2, 2008, and updated in February 2011 and March 2014.

OBJECTIVES

To determine the effectiveness of MAH compared with placebo and standard care, in adults receiving palliative care on their QoL and survival, and to assess for potential adverse events.

SEARCH METHODS

We searched for studies in the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, CANCERLIT, CareSearch, Dissertation Abstracts, Science Citation Index and the reference lists of all eligible studies, key textbooks, and previous systematic reviews. The date of the latest search conducted on CENTRAL, MEDLINE, and Embase was 17 November 2022.

SELECTION CRITERIA

We included all relevant randomised controlled trials (RCTs) of studies of MAH in adults receiving palliative care aged 18 and above. The criteria for inclusion was the comparison of MAH to placebo or standard care.

DATA COLLECTION AND ANALYSIS

Three review authors independently reviewed titles and abstracts for relevance, and two review authors extracted data and performed risk of bias assessment. The primary outcome was QoL using validated scales; secondary outcomes were survival and adverse events. For continuous outcomes, we measured the arithmetic mean and standard deviation (SD), and reported the mean difference (MD) with 95% confidence interval (CI) between groups. For dichotomous outcomes, we estimated and compared the risk ratio (RR) with 95% CIs between groups. For time-to-event data, we planned to calculate the survival time from the date of randomisation and to estimate and express the intervention effect as the hazard ratio (HR). We assessed the certainty of evidence using GRADE and created two summary of findings tables.  MAIN RESULTS: We identified one new study (200 participants), for a total of four studies included in this update (422 participants). All participants had a diagnosis of advanced cancer. With the exception of 29 participants who had a haematological malignancy, all others were solid organ cancers. Two studies each compared MAH to placebo and standard care. There were too few included studies to evaluate different subgroups, such as type of participant, intervention, timing of intervention, and study site. We considered one study to be at high risk of performance and detection bias due to lack of blinding; otherwise, risk of bias was assessed as low or unclear. MAH compared with placebo Quality of life One study measured change in QoL at one week using Functional Assessment of Cancer Therapy - General (FACT-G) (scale from 0 to 108; higher score = better QoL). No data were available from the other study. We are uncertain whether MAH improves QoL (MD 4.10, 95% CI -1.63 to 9.83; 1 study, 93 participants, very low-certainty evidence). Survival One study reported on survival from study enrolment to last date of follow-up or death. We were unable to estimate HR. No data were available from the other study. We are uncertain whether MAH improves survival (1 study, 93 participants, very low-certainty evidence).  Adverse events One study reported on intensity of adverse events at two days using a numeric rating scale (scale from 0 to 10; lower score = less toxicity). No data were available from the other study. We are uncertain whether MAH leads to adverse events (injection site pain: MD 0.35, 95% CI -1.19 to 1.89; injection site swelling MD -0.59, 95% CI -1.40 to 0.22; 1 study, 49 participants, very low-certainty evidence).  MAH compared with standard care Quality of life No data were available for QoL. Survival One study measured survival from randomisation to last date of follow-up at 14 days or death. No data were available from the other study. We are uncertain whether MAH improves survival (HR 0.36, 95% CI 0.22 to 0.59; 1 study, 200 participants, very low-certainty evidence).  Adverse events Two studies measured adverse events at follow-up (range 2 to 14 days). We are uncertain whether MAH leads to adverse events (RR 11.62, 95% CI 1.62 to 83.41; 2 studies, 242 participants, very low-certainty evidence).  AUTHORS' CONCLUSIONS: Since the previous update of this review, we have found one new study. In adults receiving palliative care in the end stage of their illness, there remains insufficient evidence to determine whether MAH improves QoL or prolongs survival, compared with placebo or standard care. Given that all participants were inpatients with advanced cancer at end of life, our findings are not transferable to adults receiving palliative care in other settings, for non-cancer, dementia or neurodegenerative diseases, or for those with an extended prognosis. Clinicians will need to make decisions based on the perceived benefits and harms of MAH for each individual's circumstances, without the benefit of high-quality evidence to guide them.

Clinically assisted hydration in patients in the last days of life ('CHELsea II' trial): a cluster randomised trial

INTRODUCTION

Provision of clinically assisted hydration (CAH) at the end of life is one of the most contentious issues in medicine. The aim of the 'CHELsea II' trial is to evaluate CAH in patients in the last days of life. The objectives are to assess the effect of CAH on delirium, audible upper airway secretions, pain and other symptoms, and overall survival, as well as the tolerability of CAH, and the health economic impact.

METHODS AND ANALYSIS

The study is a cluster randomised trial, involving 80 sites/clusters (mainly hospices) and 1600 patients. Sites will be randomised to an intervention, and this will become the standard of care during the trial. Intervention 'A' involves continuance of drinking (if appropriate), mouth care and usual end-of-life care. Intervention 'B' involves continuance of drinking, mouth care, usual end-of-life care and CAH, that is, parenteral fluids. The fluid may be given intravenously or subcutaneously, the type will be dextrose saline (4% dextrose, 0.18% sodium chloride) and the volume will be dependent on weight.Participants will be assessed every 4 hours by the clinical team. The primary endpoint is the proportion of participants who develop delirium determined using the Nursing Delirium Screening Scale (using a cut-off score of ≥2). A mixed-effects logistic regression will be used to assess the difference in the odds of developing delirium between the interventions.

ETHICS AND DISSEMINATION

Ethical committee approval has been granted by the Brighton and Sussex Research Ethics Committee (REC) (main REC for the UK: reference-IRAS 313640), and by the Scotland A REC (REC for adults with incapacity in Scotland: reference-22/SS/0053-IRAS-317637). The consent process follows the Mental Capacity Act: if the patient has capacity, then consent will be sought in the normal way; if the patient does not have capacity, then a personal/nominated consultee will be approached for advice about the patient entering the study. The consent process is slightly different in Scotland.The results of the trial will be published in general medical/palliative care journals, and presented at general medical/palliative care conferences.

TRIAL REGISTRATION NUMBER

ISRCTN65858561.

Outcomes and measures of delirium interventional studies in palliative care to inform a core outcome set: A systematic review

BACKGROUND

Trials of interventions for delirium in various patient populations report disparate outcomes and measures but little is known about those used in palliative care trials. A core outcome set promotes consistency of outcome selection and measurement.

AIM

To inform core outcome set development by examining outcomes, their definitions, measures and time-points in published palliative care studies of delirium prevention or treatment delirium interventions.

DESIGN

Prospectively registered systematic review adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses.

DATA SOURCES

We searched six electronic databases (1980-November 2020) for original studies, three for relevant reviews and the International Clinical Trials Registry Platform for unpublished studies and ongoing trials. We included randomised, quasi-randomised and non-randomised intervention studies of pharmacological and non-pharmacological delirium prevention and/or treatment interventions.

RESULTS

From 13/3244 studies (2863 adult participants), we identified 9 delirium-specific and 13 non-delirium specific outcome domains within eight Core Outcome Measures in Effectiveness Trials (COMET) taxonomy categories. There were multiple and varied outcomes and time points in each domain. The commonest delirium specific outcome was delirium severity (n = 7), commonly using the Memorial Delirium Assessment Scale (6/8 studies, 75%). Four studies reported delirium incidence. Non-delirium specific outcomes included mortality, agitation, adverse events, other symptoms and quality of life.

CONCLUSION

The review identified few delirium interventions with heterogeneity in outcomes, their definition and measurement, highlighting the need for a uniform approach. Findings will inform the next stage to develop consensus for a core outcome set to inform delirium interventional palliative care research.

Non-pharmacological interventions for preventing delirium in hospitalised non-ICU patients

BACKGROUND

Delirium is an acute neuropsychological disorder that is common in hospitalised patients. It can be distressing to patients and carers and it is associated with serious adverse outcomes. Treatment options for established delirium are limited and so prevention of delirium is desirable. Non-pharmacological interventions are thought to be important in delirium prevention.  OBJECTIVES: To assess the effectiveness of non-pharmacological interventions designed to prevent delirium in hospitalised patients outside intensive care units (ICU).

SEARCH METHODS

We searched ALOIS, the specialised register of the Cochrane Dementia and Cognitive Improvement Group, with additional searches conducted in MEDLINE, Embase, PsycINFO, CINAHL, LILACS, Web of Science Core Collection, ClinicalTrials.gov and the World Health Organization Portal/ICTRP to 16 September 2020. There were no language or date restrictions applied to the electronic searches, and no methodological filters were used to restrict the search.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of single and multicomponent non-pharmacological interventions for preventing delirium in hospitalised adults cared for outside intensive care or high dependency settings. We only included non-pharmacological interventions which were designed and implemented to prevent delirium.  DATA COLLECTION AND ANALYSIS: Two review authors independently examined titles and abstracts identified by the search for eligibility and extracted data from full-text articles. Any disagreements on eligibility and inclusion were resolved by consensus. We used standard Cochrane methodological procedures. The primary outcomes were: incidence of delirium; inpatient and later mortality; and new diagnosis of dementia. We included secondary and adverse outcomes as pre-specified in the review protocol. We used risk ratios (RRs) as measures of treatment effect for dichotomous outcomes and between-group mean differences for continuous outcomes. The certainty of the evidence was assessed using GRADE. A complementary exploratory analysis was undertaker using a Bayesian component network meta-analysis fixed-effect model to evaluate the comparative effectiveness of the individual components of multicomponent interventions and describe which components were most strongly associated with reducing the incidence of delirium.

MAIN RESULTS

We included 22 RCTs that recruited a total of 5718 adult participants. Fourteen trials compared a multicomponent delirium prevention intervention with usual care. Two trials compared liberal and restrictive blood transfusion thresholds. The remaining six trials each investigated a different non-pharmacological intervention. Incidence of delirium was reported in all studies.  Using the Cochrane risk of bias tool, we identified risks of bias in all included trials. All were at high risk of performance bias as participants and personnel were not blinded to the interventions. Nine trials were at high risk of detection bias due to lack of blinding of outcome assessors and three more were at unclear risk in this domain.  Pooled data showed that multi-component non-pharmacological interventions probably reduce the incidence of delirium compared to usual care (10.5% incidence in the intervention group, compared to 18.4% in the control group, risk ratio (RR) 0.57, 95% confidence interval (CI) 0.46 to 0.71, I2 = 39%; 14 studies; 3693 participants; moderate-certainty evidence, downgraded due to risk of bias).  There may be little or no effect of multicomponent interventions on inpatient mortality compared to usual care (5.2% in the intervention group, compared to 4.5% in the control group, RR 1.17, 95% CI 0.79 to 1.74, I2 = 15%; 10 studies; 2640 participants; low-certainty evidence downgraded due to inconsistency and imprecision).  No studies of multicomponent interventions reported data on new diagnoses of dementia.  Multicomponent interventions may result in a small reduction of around a day in the duration of a delirium episode (mean difference (MD) -0.93, 95% CI -2.01 to 0.14 days, I2 = 65%; 351 participants; low-certainty evidence downgraded due to risk of bias and imprecision). The evidence is very uncertain about the effect of multicomponent interventions on delirium severity (standardised mean difference (SMD) -0.49, 95% CI -1.13 to 0.14, I2=64%; 147 participants; very low-certainty evidence downgraded due to risk of bias and serious imprecision). Multicomponent interventions may result in a reduction in hospital length of stay compared to usual care (MD -1.30 days, 95% CI -2.56 to -0.04 days, I2=91%; 3351 participants; low-certainty evidence downgraded due to risk of bias and inconsistency), but little to no difference in new care home admission at the time of hospital discharge (RR 0.77, 95% CI 0.55 to 1.07; 536 participants; low-certainty evidence downgraded due to risk of bias and imprecision). Reporting of other adverse outcomes was limited.  Our exploratory component network meta-analysis found that re-orientation (including use of familiar objects), cognitive stimulation and sleep hygiene were associated with reduced risk of incident delirium. Attention to nutrition and hydration, oxygenation, medication review, assessment of mood and bowel and bladder care were probably associated with a reduction in incident delirium but estimates included the possibility of no benefit or harm.  Reducing sensory deprivation, identification of infection, mobilisation and pain control all had summary estimates that suggested potential increases in delirium incidence, but the uncertainty in the estimates was substantial.  Evidence from two trials suggests that use of a liberal transfusion threshold over a restrictive transfusion threshold probably results in little to no difference in incident delirium (RR 0.92, 95% CI 0.62 to 1.36; I2 = 9%; 294 participants; moderate-certainty evidence downgraded due to risk of bias).  Six other interventions were examined, but evidence for each was limited to single studies and we identified no evidence of delirium prevention.  AUTHORS' CONCLUSIONS: There is moderate-certainty evidence regarding the benefit of multicomponent non-pharmacological interventions for the prevention of delirium in hospitalised adults, estimated to reduce incidence by 43% compared to usual care. We found no evidence of an effect on mortality. There is emerging evidence that these interventions may reduce hospital length of stay, with a trend towards reduced delirium duration, although the effect on delirium severity remains uncertain. Further research should focus on implementation and detailed analysis of the components of the interventions to support more effective, tailored practice recommendations.

Compromised end-of-life syndrome: Concept development from the condition of adults and older adults in palliative care

PURPOSE

This study aimed to develop the nursing diagnosis concept "compromised end-of-life syndrome" in palliative care.

METHODS

The authors used the integrative strategy by Meleis to develop the concept in this study and identifying clinical indicators from a literature review. For data organization, we applied the Preferred Reporting Items for Systematic Reviews and Metanalysis (PRISMA).

FINDINGS

Some clusters of unpleasant signs and symptoms in palliative care patients at the end of life, such as pain, dyspnea, depression, constipation, and anxiety, were identified. Through conceptualization, the authors propose a new nursing diagnosis, "compromised end-of-life syndrome." The manuscript includes a model case of a patient with nursing diagnosis syndrome as a clinical example.

CONCLUSIONS

Simultaneous patterns of signs and symptoms present in the literature reinforce the utility of the proposition of end-of-life syndrome as a nursing diagnostic construct.

IMPLICATIONS FOR NURSING PRACTICE

The concept development related to patients' unpleasant signs and symptoms critically ill at palliative care supports the proposition of a new nursing diagnosis relevant to selecting adequate nursing interventions and nursing outcomes. Some clusters of unpleasant signs and symptoms in palliative care patients at the end of life, such as pain, dyspnea, depression, constipation, and anxiety were identified. Conceptualization was used to propose a new nursing diagnosis, "compromised end-of-life syndrome." A model case of a patient with nursing diagnosis syndrome is described as a clinical example.

CONCLUSION

Simultaneous patterns of signs and symptoms present in the literature reinforce the utility of the proposition of end-of-life syndrome as nursing diagnostic construct.

IMPLICATIONS FOR NURSING PRACTICE

The concept development related to patients' unpleasant signs and symptoms critically ill at palliative care supports the proposition of a new nursing diagnosis relevant to selecting adequate nursing interventions and nursing outcomes.

Non-pharmacological interventions for preventing delirium in hospitalised non-ICU patients

BACKGROUND

Delirium is an acute neuropsychological disorder that is common in hospitalised patients. It can be distressing to patients and carers and it is associated with serious adverse outcomes. Treatment options for established delirium are limited and so prevention of delirium is desirable. Non-pharmacological interventions are thought to be important in delirium prevention.  OBJECTIVES: To assess the effectiveness of non-pharmacological interventions designed to prevent delirium in hospitalised patients outside intensive care units (ICU).

SEARCH METHODS

We searched ALOIS, the specialised register of the Cochrane Dementia and Cognitive Improvement Group, with additional searches conducted in MEDLINE, Embase, PsycINFO, CINAHL, LILACS, Web of Science Core Collection, ClinicalTrials.gov and the World Health Organization Portal/ICTRP to 16 September 2020. There were no language or date restrictions applied to the electronic searches, and no methodological filters were used to restrict the search.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of single and multicomponent non-pharmacological interventions for preventing delirium in hospitalised adults cared for outside intensive care or high dependency settings. We only included non-pharmacological interventions which were designed and implemented to prevent delirium.  DATA COLLECTION AND ANALYSIS: Two review authors independently examined titles and abstracts identified by the search for eligibility and extracted data from full-text articles. Any disagreements on eligibility and inclusion were resolved by consensus. We used standard Cochrane methodological procedures. The primary outcomes were: incidence of delirium; inpatient and later mortality; and new diagnosis of dementia. We included secondary and adverse outcomes as pre-specified in the review protocol. We used risk ratios (RRs) as measures of treatment effect for dichotomous outcomes and between-group mean differences for continuous outcomes. The certainty of the evidence was assessed using GRADE. A complementary exploratory analysis was undertaker using a Bayesian component network meta-analysis fixed-effect model to evaluate the comparative effectiveness of the individual components of multicomponent interventions and describe which components were most strongly associated with reducing the incidence of delirium.

MAIN RESULTS

We included 22 RCTs that recruited a total of 5718 adult participants. Fourteen trials compared a multicomponent delirium prevention intervention with usual care. Two trials compared liberal and restrictive blood transfusion thresholds. The remaining six trials each investigated a different non-pharmacological intervention. Incidence of delirium was reported in all studies.  Using the Cochrane risk of bias tool, we identified risks of bias in all included trials. All were at high risk of performance bias as participants and personnel were not blinded to the interventions. Nine trials were at high risk of detection bias due to lack of blinding of outcome assessors and three more were at unclear risk in this domain.  Pooled data showed that multi-component non-pharmacological interventions probably reduce the incidence of delirium compared to usual care (10.5% incidence in the intervention group, compared to 18.4% in the control group, risk ratio (RR) 0.57, 95% confidence interval (CI) 0.46 to 0.71, I2 = 39%; 14 studies; 3693 participants; moderate-certainty evidence, downgraded due to risk of bias).  There may be little or no effect of multicomponent interventions on inpatient mortality compared to usual care (5.2% in the intervention group, compared to 4.5% in the control group, RR 1.17, 95% CI 0.79 to 1.74, I2 = 15%; 10 studies; 2640 participants; low-certainty evidence downgraded due to inconsistency and imprecision).  No studies of multicomponent interventions reported data on new diagnoses of dementia.  Multicomponent interventions may result in a small reduction of around a day in the duration of a delirium episode (mean difference (MD) -0.93, 95% CI -2.01 to 0.14 days, I2 = 65%; 351 participants; low-certainty evidence downgraded due to risk of bias and imprecision). The evidence is very uncertain about the effect of multicomponent interventions on delirium severity (standardised mean difference (SMD) -0.49, 95% CI -1.13 to 0.14, I2=64%; 147 participants; very low-certainty evidence downgraded due to risk of bias and serious imprecision). Multicomponent interventions may result in a reduction in hospital length of stay compared to usual care (MD -1.30 days, 95% CI -2.56 to -0.04 days, I2=91%; 3351 participants; low-certainty evidence downgraded due to risk of bias and inconsistency), but little to no difference in new care home admission at the time of hospital discharge (RR 0.77, 95% CI 0.55 to 1.07; 536 participants; low-certainty evidence downgraded due to risk of bias and imprecision). Reporting of other adverse outcomes was limited.  Our exploratory component network meta-analysis found that re-orientation (including use of familiar objects), cognitive stimulation and sleep hygiene were associated with reduced risk of incident delirium. Attention to nutrition and hydration, oxygenation, medication review, assessment of mood and bowel and bladder care were probably associated with a reduction in incident delirium but estimates included the possibility of no benefit or harm.  Reducing sensory deprivation, identification of infection, mobilisation and pain control all had summary estimates that suggested potential increases in delirium incidence, but the uncertainty in the estimates was substantial.  Evidence from two trials suggests that use of a liberal transfusion threshold over a restrictive transfusion threshold probably results in little to no difference in incident delirium (RR 0.92, 95% CI 0.62 to 1.36; I2 = 9%; 294 participants; moderate-certainty evidence downgraded due to risk of bias).  Six other interventions were examined, but evidence for each was limited to single studies and we identified no evidence of delirium prevention.  AUTHORS' CONCLUSIONS: There is moderate-certainty evidence regarding the benefit of multicomponent non-pharmacological interventions for the prevention of delirium in hospitalised adults, estimated to reduce incidence by 43% compared to usual care. We found no evidence of an effect on mortality. There is emerging evidence that these interventions may reduce hospital length of stay, with a trend towards reduced delirium duration, although the effect on delirium severity remains uncertain. Further research should focus on implementation and detailed analysis of the components of the interventions to support more effective, tailored practice recommendations.

Artificial hydration at the end of life: balancing benefits and risks in the absence of conclusive evidence

There is a lack of clear evidence regarding the benefits and harm of artificial hydration at the end of life. Trial findings are conflicting and inconclusive, offering little basis for recommendations. As a result, the advantages and disadvantages of artificial hydration remain largely anecdotal, and decisions about its use, withholding or withdrawal are often based on opinion rather than evidence. In certain circumstances, some patients who are dying might derive benefit from artificial hydration in terms of reducing specific symptoms, such as delirium. This article explores the central questions pertaining to artificial hydration at the end of life by undertaking a critical exploration of the relevant literature.

Quality assurance for care of the dying: engaging with clinical services to facilitate a regional cross-sectional survey of bereaved relatives' views

BACKGROUND

Globally, having the 'patient and /or family voice' engaged when measuring quality of care for the dying is fundamentally important. This is particularly pertinent within the United Kingdom, where changes to national guidance about care provided to dying patients has heightened the importance of quality assurance and user-feedback. Our main aim was to engage with clinical services (hospice, hospital and community settings) within a specific English region and conduct a bereaved relatives' cross-sectional survey about quality of care. Our secondary aim was to explore levers and barriers to project participation as perceived by organisational representatives.

METHODS

Each organisation identified a consecutive sample of next-of-kin to adult patients who died between 1st September and 30th November 2014. Those who had an unexpected death or were involved in a formal complaint were excluded. The 'Care Of the Dying Evaluation' (CODE™) questionnaire was posted out three months following the bereavement. One-to-one interviews were undertaken with a purposive sample of organisational representatives to explore experiences about project participation.

RESULTS

Of the 30 invited organisations, 18 were able to participate comprising: 7 hospitals, 7 hospices and 4 community settings. There were 1774 deaths which met the inclusion criteria but 460 (26%) were excluded due to inaccurate next-of-kin details. Subsequently, 1283 CODE™ questionnaires were sent out, with 354 completed (27% response rate). Overall, most participants perceived good quality of care. A notable minority reported poor care for symptom control and communication especially within the hospital. Nine interviews were conducted - levers to project participation included the 'significance of user-feedback and the opportunity to use results in a meaningful way'; the main barrier was related to 'concern about causing distress to bereaved relatives'.

CONCLUSIONS

Overall, being able to engage with 18 (60%) organisations within the region and conduct the bereaved relatives' survey showed success of this initiative and was supported by interview findings. The potential to be able to benchmark user-feedback against other organisations was thought to help focus on areas to develop services. This type of quality assurance project could form a template model and be replicated on a national and international level.

A cluster randomised feasibility trial of clinically assisted hydration in cancer patients in the last days of life

BACKGROUND

The provision of clinically assisted hydration at the end-of-life is one of the most contentious issues in medicine.

AIM

The aim of this feasibility study was to answer the question 'can a definitive (adequately powered) study be done?'

DESIGN

The study was a cluster randomised trial, with sites randomised on a one-to-one basis to intervention 'A' (regular mouth care and usual other care) or intervention 'B' (clinically assisted hydration, mouth care and usual other care). Participants were assessed every 4 h, and data collected on clinical problems, therapeutic interventions and overall survival.

SETTING/PARTICIPANTS

The study was conducted at 12 sites/'clusters' with specialist palliative care teams (4 cancer centres and 8 hospices), and participants were cancer patients in the last week of life who were unable to maintain sufficient oral fluid intake.

RESULTS

The study achieved its pre-determined criteria for success. Two hundred patients were recruited to the study, and 199 participants completed the study, over a 1-year period. A total of 38.5% participants discontinued clinically assisted hydration due to adverse effects: none of these adverse events were rated as 'severe' or worse in intensity. The primary reasons for discontinuation were site problems ( n = 2), localised oedema ( n = 13), generalised oedema ( n = 5), respiratory secretions ( n = 6) and nausea and vomiting ( n = 1).

CONCLUSION

The results of this feasibility study suggest that a definitive study can be done, but that minor changes are needed to the protocol to standardise the administration of clinically assisted hydration (which may reduce the incidence of certain adverse effects).