Developing a quick and practical screen to improve the identification of poor hydration in geriatric and rehabilitative care

Evaluation of Delirium Among Elders in the Emergency Department: A Cross-Sectional Study

BACKGROUND

Health care professionals underestimate the recognition of delirium in emergency departments (EDs). In these settings, between 57% and 83% of cases of delirium go undetected. When delirium occurs, it causes an increase in the length of hospitalization, readmissions within 30 days, and mortality. No studies were carried out in Italy to assess the prevalence of delirium among elders in EDs.

OBJECTIVES

The primary goal of the study was to evaluate the prevalence of the risk of delirium in people 65 years and older hospitalized in the ED for a minimum of 8 hours. The study's secondary goal was to identify the variables that influenced the risk of delirium.

METHOD

A multicenter cross-sectional study was conducted in 2 EDs. The risk of delirium was assessed using the delirium screening tool 4 A's test. One hundred patients were enrolled. Data collection took place from June 28 to August 31, 2022.

RESULTS

The risk of delirium was detected in 29% of the sample, whereas the risk of cognitive impairment was 13%. The use of psychotropic drugs increased the risk of delirium by 11.8 times (odds ratio [OR], 11.80; P = .003). Bed confinement increased the risk by 4.3 times (OR, 4.31; P = .009). Being dehydrated increased the risk of onset by 4.6 times (OR, 4.62; P = .010). Having dementia increased the risk of delirium manifestation by 4.4 times (OR, 4.35; P = .021).

DISCUSSION

The risk of delirium was detected in a considerable portion of the sample. The results of this study can be used by health care professionals to implement preventive measures as well as support clinical judgment and establish priorities of care for patients at risk of developing delirium.

Effect of a Hydration Management Program on Older Adults' Fluid Consumption and Dehydration Parameters: A Quasi-Experimental Study

The purpose of the current study was to assess effects of a hydration management program on the fluid consumption and dehydration parameters (i.e., dehydration risk scores, urine specific gravity, and urine color) of older adults. The study was conducted as a pre-/post-test quasi-experimental study with a control group (intervention group: n = 42, control group: n = 37). The hydration management program applied to the intervention group was completed in 1 week. After the intervention, the knowledge and awareness of the intervention group regarding fluid consumption increased (p = 0.001). The dehydration risk score of the intervention group was significantly lower than that of the control group (p = 0.0001). There was a significant change in average 3-day water intake (p = 0.0001), urine specific gravity value (p = 0.01), and urine color scale score (p = 0.0001) in the intervention group between pre- and post-test. The hydration management program provided a significant improvement in daily water intake and dehydration risk score and increased knowledge and awareness among older adults concerning the importance of fluid intake. [Journal of Gerontological Nursing, 47(9), 40-48.].

Fluid Intake Monitoring Systems for the Elderly: A Review of the Literature

Fluid intake monitoring is an essential component in preventing dehydration and overhydration, especially for the senior population. Numerous critical health problems are associated with poor or excessive drinking such as swelling of the brain and heart failure. Real-time systems for monitoring fluid intake will not only measure the exact amount consumed by the users, but could also motivate people to maintain a healthy lifestyle by providing feedback to encourage them to hydrate regularly throughout the day. This paper reviews the most recent solutions to automatic fluid intake monitoring both commercially and in the literature. The available technologies are divided into four categories: wearables, surfaces with embedded sensors, vision- and environmental-based solutions, and smart containers. A detailed performance evaluation was carried out considering detection accuracy, usability and availability. It was observed that the most promising results came from studies that used data fusion from multiple technologies, compared to using an individual technology. The areas that need further research and the challenges for each category are discussed in detail.

Fluid Needs in the Older Adult Receiving Tube Feedings

Fluid imbalance can occur quickly in older adults and in others who cannot express thirst or are in a setting where fluid status is not closely monitored. In tube-fed individuals receiving inadequate calories, severe malnutrition may occur in weeks to months, but improper water intake may lead to critical fluid imbalances in a matter of days. Simplistic equations frequently used to determine fluid needs in adults include milliliters per kilogram of body weight and milliliters per energy (kilocalories) consumed or per energy (kilocalories) need and variations of the Holliday-Segar formula. None of these fluid-requirement equations have been validated through evidenced-based science, and research investigations have revealed that they can grossly overestimate or underestimate fluid needs in the older adult. Clinicians need guidance to better estimate initial fluid needs for the older adult receiving tube feedings and to provide proper close monitoring afterward to avert preventable fluid imbalance-related hospital readmissions, morbidities, and mortalities in this patient population.

Derivation of the first clinical diagnostic models for dehydration severity in patients over five years with acute diarrhea

Diarrheal diseases lead to an estimated 1.3 million deaths each year, with the majority of those deaths occurring in patients over five years of age. As the severity of diarrheal disease can vary widely, accurately assessing dehydration status remains the most critical step in acute diarrhea management. The objective of this study is to empirically derive clinical diagnostic models for assessing dehydration severity in patients over five years with acute diarrhea in low resource settings. We enrolled a random sample of patients over five years with acute diarrhea presenting to the icddr,b Dhaka Hospital. Two blinded nurses independently assessed patients for symptoms/signs of dehydration on arrival. Afterward, consecutive weights were obtained to determine the percent weight change with rehydration, our criterion standard for dehydration severity. Full and simplified ordinal logistic regression models were derived to predict the outcome of none (<3%), some (3-9%), or severe (>9%) dehydration. The reliability and accuracy of each model were assessed. Bootstrapping was used to correct for over-optimism and compare each model's performance to the current World Health Organization (WHO) algorithm. 2,172 patients were enrolled, of which 2,139 (98.5%) had complete data for analysis. The Inter-Class Correlation Coefficient (reliability) was 0.90 (95% CI = 0.87, 0.91) for the full model and 0.82 (95% CI = 0.77, 0.86) for the simplified model. The area under the Receiver-Operator Characteristic curve (accuracy) for severe dehydration was 0.79 (95% CI: 0.76-0.82) for the full model and 0.73 (95% CI: 0.70, 0.76) for the simplified model. The accuracy for both the full and simplified models were significantly better than the WHO algorithm (p<0.001). This is the first study to empirically derive clinical diagnostic models for dehydration severity in patients over five years. Once prospectively validated, the models may improve management of patients with acute diarrhea in low resource settings.

Bioelectrical Impedance Versus Biochemical Analysis of Hydration Status: Predictive Value for Prolonged Hospitalisation and Poor Discharge Destination for Older Patients

Dehydration is prevalent in hospitalised patients and is associated with increased morbidity and mortality, particularly among the elderly (≥65 years). We aimed at comparing the performance of intracellular water to extracellular water ratio (ICW/ECW), calculated through a bioelectrical impedance analysis (BIA) of blood urea nitrogen, with the creatinine ratio (BUN/Cr) to predict poor outcomes in a cohort of prospectively identified patients. Data were combined from a cohort of elderly patients (≥65 years) admitted to hospital with fragility fracture (n = 125) and older adults aged ≥50 years admitted to hospital with stroke (n = 40). The association between hydration status and study outcomes (unfavourable discharge destination (rehabilitation, another ward, or death) and prolonged hospitalisation (>10 days)) was examined using logistic regression. The overall diagnostic accuracy of each hydration status measurement was assessed using the area under the receiver operating characteristic (ROC) curve. In 165 participants (mean age (SD) of 76.7 (9.2) years), an ICW/ECW ratio below the 25th percentile was associated with increased odds of poor discharge destination (OR (95% CI) = 4.25 (1.59–11.34)). Neither the relationship between the BUN/Cr ratio and prolonged stay nor discharge destination was significant. A BIA could be used utilised in conjunction with biochemical measurements to inform patient prognosis.

Signs of Dehydration after Hip Fracture Surgery: An Observational Descriptive Study

Background and Objectives: Dehydration might be an issue after hip fracture surgery, but the optimal tools to identify the dehydrated condition have not been determined. The aim of the present study was to compare the characteristics of elderly postoperative patients who were classified as dehydrated according to the methods used in the clinic. Materials and Methods: Thirty-eight patients aged between 65 and 97 (mean, 82) years were studied after being admitted to a geriatric department for rehabilitation after hip fracture surgery. Each patient underwent blood analyses, urine sampling, and clinical examinations. Results: Patients ingested a mean of 1,008 mL (standard deviation, 309 mL) of fluid during their first day at the clinic. Serum osmolality increased significantly with the plasma concentrations of sodium, creatinine, and urea. Seven patients had high serum osmolality (≥300 mosmol/kg) that correlated with the presence of tongue furrows (p < 0.04), poor skin turgor (p < 0.03), and pronounced albuminuria (p < 0.03). Eight patients had concentrated urine (urine-specific gravity ≥ 1.025) that correlated with a low intake of liquid and with a decrease in body weight during the past month of −3.0 kg (25–75 th percentiles, −5.1 to −0.9) versus +0.2 (−1.9 to +2.7) kg (p < 0.04). Conclusions: Renal fluid conservation of water, either in the form of hyperosmolality or concentrated urine, was found in 40% of the patients after hip fracture surgery. Hyperosmolality might not indicate a more severe fluid deficit than is indicated by concentrated urine but suggests an impaired ability to concentrate the urine.

Diagnostic efficacy of bedside ultrasound to detect dehydration in older patients attending an emergency care unit

BACKGROUND

The diagnosis of dehydration in older patients remains a challenge because clinical and laboratory signs are unspecific. The use of B‑Mode ultrasound of the inferior vena cava is proposed to aid in the diagnosis but data concerning diagnostic efficacy of bedside ultrasound are lacking.

METHODS

In this study 78 patients ≥65 years old referred to the emergency unit of a university hospital and identified as being dehydrated by applying clinical signs were compared with a reference of 121 patients. The diameter of the inferior vena cava (IVC) was assessed by ultrasound while compressing the IVC during an inspiratory maneuver and the minimum and maximum diameter in M‑Mode.

RESULTS

Significant differences were found concerning compressibility, variability of the diameter assessed by M‑Mode and the diameter during an inspiratory maneuver of the IVC (<0.001); however, a receiver operator characteristics (ROC) showed only moderate values for diagnostic efficacy for all these parameters where the best result was found for the inspiratory maneuver (Area under the curve [AUC] = 0.73). To reach a specificity of 0.8 to diagnose dehydration, a cut-off value of ≤0.4 cm for IVC diameter was suitable.

CONCLUSION

Ultrasound of the IVC can easily be applied in a bedside setting and may be helpful in identifying dehydration in older patients; however, this remains challenging and a synopsis covering clinical and technical data is indispensable.

The association between hydration status and cognitive function among free-living elderly volunteers

Background

Ageing is inevitably associated with a progressive cognitive decline. With the rising percentage of the elderly in society, the number of people with dementia and cognitive impairment increases. Water is a vital ingredient that must be included in the diet. The impact of hydration status on cognitive performance has been studied only a little so far.

Aims

The objective of the study was to investigate the relation between the hydration status and the cognitive function.

Methods

The study was conducted among 60 free-living volunteers, aged 60–93 years. Data on water consumption were gathered based on 3-day records. The hydration status was assessed in morning urine samples by evaluating urine specific gravity. The cognitive function was tested using the Mini Mental State Examination (MMSE), the Babcock Story Recall Test and the Trail Making Test. Information about depression was gathered by the Geriatric Depression Scale.

Results

The mean daily total water intake was 2441 ± 622 ml, and 70% of respondents met the reference values for an adequate intake. The mean urine specific gravity (1.013 g/cm³, range of 1.004–1.025 g/cm³) indicated that most of the individuals were in a good hydration state. The average result of MMSE was 27.8, which is connected with mild cognitive impairment. There was no significant relationship between the hydration status and the results of the cognitive function test in the studied population.

Discussion/conclusion

As the elderly volunteers had a good hydration status, there was no significant relationship between cognitive performance and urine specific gravity. It is necessary to replicate the findings of this study with a larger and more diverse sample of older adults.

An Innovative Approach to Adequate Oral Hydration in an Inpatient Geriatric Psychiatry Unit

Suboptimal hydration status and dehydration are problems that often exacerbate comorbid conditions in geriatric patients. At a Veterans Administration Hospital, it was observed that suboptimal hydration status in Veterans hospitalized in the geriatric psychiatry unit was a contributing factor in the worsening of their psychiatric and medical conditions. A quality improvement project was chartered to improve hydration in this group of patients. Using a three-pronged intervention approach (i.e., providing flavored water, providing larger cups, and increasing the prompting by nurses for patients to drink more), the project was successful. The goal was to increase average daily fluid intake by 125 mL; the result was an increase of 700 mL. This project has been sustained and the interventions have also benefitted non-geriatric psychiatry in-patients. [Journal of Psychosocial Nursing and Mental Health Services, 57(4), 15-20.].

Hydration Status of Assisted Living Memory Care Residents

Water intake and hydration status of assisted living memory care (ALMC) residents were evaluated. Thirty-two residents (eight men; mean age 86.5 years; Global Deterioration Scale [GDS] 3 to 7) from four ALMC units participated. Ingested food and fluid amount, type, and time, and ingestion behaviors were observed from 7:00 a.m. to 7:00 p.m. Related factors were obtained from chart review/participant survey. Mean fluid intake was 1,160.16 mL; mean water intake from food and fluid was 56.55% (SD = 23.4%) of recommended water intake (RWI). Only one participant met 100% RWI. Using osmolality laboratory results (available for 21 participants), five participants were hydrated, whereas eight (38.1%) participants were in impending dehydration and dehydration categories, respectively. Fluid intake, GDS, and level of assistance during meals predicted RWI. Water intake of ALMC residents is inadequate, placing them at risk for dehydration, and justifies development and implementation of care standards for increasing water intake. [Journal of Gerontological Nursing, 45(4), 21-29.].

Signs of Dehydration in Nursing Home Residents

OBJECTIVES

Although dehydration can affect mental and physical health, there is no clear, consistent, and reproducible diagnostic tool for this condition in older people. We applied multiple methods to detect dehydration with the aim of assessing the value of using urine analysis for this purpose.

DESIGN

Nonrandomized cohort study.

SETTING AND PARTICIPANTS

Sixty nursing home residents, aged 64-103 (mean 84) years.

METHODS

Sampling of morning urine, blood analyses, and clinical examination. A previously validated algorithm summarized the urine specific gravity, osmolality, creatinine, and color to a Fluid Retention Index (FRI).

RESULTS

The cut-off for renal fluid conservation consistent with dehydration (FRI ≥ 4.0) was reached by 51% of the cohort. No statistically significant linear correlation was found between FRI and serum osmolality (mean 307.5 mOsmol/kg) or plasma sodium (mean 139 mmol/L), but the subjects reported less thirst with increasing FRI scores (linear correlation r = -0.35; P < .03). Clinical examinations of mucous membranes and tongue furrows did not correlate with other markers of dehydration. Subjects with sunken eyes had higher C-reactive protein (P < .02) and lower albumin (P < .002) concentrations in plasma than the others, while impaired skin turgor only correlated with age (P < .04).

CONCLUSIONS/IMPLICATIONS

Renal fluid conservation consistent with dehydration was found in half of the nursing home residents, which could partially be accounted for by decreased thirst. Clinical examinations probably reflected the physical status and age more than dehydration. The lack of correlation between the serum osmolality and the FRI, both of which are purported to be gold standards for dehydration, raises questions about whether a gold standard exists.

Risk factors associated with dehydration in older people living in nursing homes: Scoping review

BACKGROUND

Dehydration in the older people is a prevalent problem that is often associated with physiological changes, physical limitations and environmental conditions.

OBJECTIVES

The scoping review was carried out to identify risk factors associated with dehydration in older people living in nursing homes.

DESIGN

The revised scoping methodology framework of Arksey and O'Malley (2005) was applied. Study selection was carried out in accordance with Davis et al. (2009) and focused on the inclusion criteria (people over 65 years old and living in nursing homes). Risk factors were classified using the geriatric assessment.

DATA SOURCES

An electronic database search was performed in PubMed, Scopus and CINAHL. The literature search was carried out between October 2016 and January 2017.

REVIEW METHODS

Thematic reporting was performed and study findings were validated through interdisciplinary meetings of experts. The quality of the papers consulted was also evaluated using the Newcastle-Ottawa Scale adapted for cross-sectional, cohort and case-control studies.

RESULTS

In all, 16 papers were analysed, all of which were observational studies. The risk of bias ranged from very low (n = 1), to medium (n = 13) and high (n = 2). The risk factors were classified in line with the different components of the geriatric assessment. In the socio-demographic characteristics age and gender were identified. In the clinical component, infections, renal and cardiovascular diseases and end-of-life situations were the most common factors highlighted in the papers analysed. With reference to the functional component, its limitation was associated with dehydration, while for factors of mental origin, it was related to dementia and behavioural disorders. Finally, the factors relating to the social component were institutionalisation, requiring a skilled level of care and it being winter.

CONCLUSIONS

The most commonly repeated factors highlighted in the review were age, gender, infections, end of life and dementia, with it being important to highlight the large number of factors in the clinical component. Even so, the great majority of the factors were unmodifiable conditions associated typically associated with the physiology of ageing.

Methods of Assessment of Hydration Status and their Usefulness in Detecting Dehydration in the Elderly

Assessment of hydration status is complex and difficult to achieve. Few assessment methods have been validated to accurately measure the fluid compartments in the body, but they have little application in practice. Different techniques have been developed to determine hydration status for the use in clinical settings, but their diagnostic accuracy remains questionable. Since many experts argue that there is no 'gold-standard' technique and one can never be achieved, this paper describes both, the benefits and limitations of the available methods and their usability in assessing hydration status of the elderly.

Clinical assessments and care interventions to promote oral hydration amongst older patients: a narrative systematic review

BACKGROUND

Older patients in hospital may be unable to maintain hydration by drinking, leading to intravenous fluid replacement, complications and a longer length of stay. We undertook a systematic review to describe clinical assessment tools which identify patients at risk of insufficient oral fluid intake and the impact of simple interventions to promote drinking, in hospital and care home settings.

METHOD

MEDLINE, CINAHL, and EMBASE databases and two internet search engines (Google and Google Scholar) were examined. Articles were included when the main focus was use of a hydration/dehydration risk assessment in an adult population with/without a care intervention to promote oral hydration in hospitals or care homes. Reviews which used findings to develop new assessments were also included. Single case reports, laboratory results only, single technology assessments or non-oral fluid replacement in patients who were already dehydrated were excluded. Interventions where nutritional intake was the primary focus with a hydration component were also excluded. Identified articles were screened for relevance and quality before a narrative synthesis. No statistical analysis was planned.

RESULTS

From 3973 citations, 23 articles were included. Rather than prevention of poor oral intake, most focused upon identification of patients already in negative fluid balance using information from the history, patient inspection and urinalysis. Nine formal hydration assessments were identified, five of which had an accompanying intervention/ care protocol, and there were no RCT or large observational studies. Interventions to provide extra opportunities to drink such as prompts, preference elicitation and routine beverage carts appeared to support hydration maintenance, further research is required. Despite a lack of knowledge of fluid requirements and dehydration risk factors amongst staff, there was no strong evidence that increasing awareness alone would be beneficial for patients.

CONCLUSION

Despite descriptions of features associated with dehydration, there is insufficient evidence to recommend a specific clinical assessment which could identify older persons at risk of poor oral fluid intake; however there is evidence to support simple care interventions which promote drinking particularly for individuals with cognitive impairment.

TRIAL REGISTRATION

PROSPERO 2014:CRD42014015178.

Effects of Ramadan Gasting on Postural Balance and Attentional Capacities in Elderly People

OBJECTIVE

To evaluate the effects of Ramadan fasting on postural balance and attentional capacities in older adults.

SETTING

the Neurophysiology department of a University Hospital.

PARTICIPANTS

Fifteen males aged between 65 and 80 years were asked to perform a postural balance protocol and a simple reaction time (SRT) test in four testing phases: one week before Ramadan (BR), during the second (SWR) and the fourth week of Ramadan (FWR) and 3 weeks after Ramadan (AR).

MEASUREMENTS

Postural balance measurements were recorded in the bipedal stance in four different conditions: firm surface/eyes open (EO), firm surface/eyes closed (EC), foam surface/EO and foam surface/EC using a force platform.

RESULTS

Results of the present study demonstrated that center of pressure (CoP) mean velocity (CoPVm), medio-lateral length (CoPLX) and antero-posterior length (CoPLY) were significantly higher during the SWR than BR. Likewise, values of CoPVm and CoPLX increased significantly during the FWR compared to BR. The CoPLX decreased significantly in the FWR compared to the SWR. Values of CoPVm and CoPLX were significantly higher AR in comparison with BR. In addition, SRT values increased significantly during the SWR and the FWR than BR.

CONCLUSION

Ramadan fasting affects postural balance and attentional capacities in the elderly mainly in the SWR and it may, therefore, increase the risk of fall and fall-related injuries. More than three weeks are needed for older adults to recover postural balance impairment due to Ramadan fasting.

Clinical symptoms, signs and tests for identification of impending and current water-loss dehydration in older people

BACKGROUND

There is evidence that water-loss dehydration is common in older people and associated with many causes of morbidity and mortality. However, it is unclear what clinical symptoms, signs and tests may be used to identify early dehydration in older people, so that support can be mobilised to improve hydration before health and well-being are compromised.

OBJECTIVES

To determine the diagnostic accuracy of state (one time), minimally invasive clinical symptoms, signs and tests to be used as screening tests for detecting water-loss dehydration in older people by systematically reviewing studies that have measured a reference standard and at least one index test in people aged 65 years and over. Water-loss dehydration was defined primarily as including everyone with either impending or current water-loss dehydration (including all those with serum osmolality ≥ 295 mOsm/kg as being dehydrated).

SEARCH METHODS

Structured search strategies were developed for MEDLINE (OvidSP), EMBASE (OvidSP), CINAHL, LILACS, DARE and HTA databases (The Cochrane Library), and the International Clinical Trials Registry Platform (ICTRP). Reference lists of included studies and identified relevant reviews were checked. Authors of included studies were contacted for details of further studies.

SELECTION CRITERIA

Titles and abstracts were scanned and all potentially relevant studies obtained in full text. Inclusion of full text studies was assessed independently in duplicate, and disagreements resolved by a third author. We wrote to authors of all studies that appeared to have collected data on at least one reference standard and at least one index test, and in at least 10 people aged ≥ 65 years, even where no comparative analysis has been published, requesting original dataset so we could create 2 x 2 tables.

DATA COLLECTION AND ANALYSIS

Diagnostic accuracy of each test was assessed against the best available reference standard for water-loss dehydration (serum or plasma osmolality cut-off ≥ 295 mOsm/kg, serum osmolarity or weight change) within each study. For each index test study data were presented in forest plots of sensitivity and specificity. The primary target condition was water-loss dehydration (including either impending or current water-loss dehydration). Secondary target conditions were intended as current (> 300 mOsm/kg) and impending (295 to 300 mOsm/kg) water-loss dehydration, but restricted to current dehydration in the final review.We conducted bivariate random-effects meta-analyses (Stata/IC, StataCorp) for index tests where there were at least four studies and study datasets could be pooled to construct sensitivity and specificity summary estimates. We assigned the same approach for index tests with continuous outcome data for each of three pre-specified cut-off points investigated.Pre-set minimum sensitivity of a useful test was 60%, minimum specificity 75%. As pre-specifying three cut-offs for each continuous test may have led to missing a cut-off with useful sensitivity and specificity, we conducted post-hoc exploratory analyses to create receiver operating characteristic (ROC) curves where there appeared some possibility of a useful cut-off missed by the original three. These analyses enabled assessment of which tests may be worth assessing in further research. A further exploratory analysis assessed the value of combining the best two index tests where each had some individual predictive ability.

MAIN RESULTS

There were few published studies of the diagnostic accuracy of state (one time), minimally invasive clinical symptoms, signs or tests to be used as screening tests for detecting water-loss dehydration in older people. Therefore, to complete this review we sought, analysed and included raw datasets that included a reference standard and an index test in people aged ≥ 65 years.We included three studies with published diagnostic accuracy data and a further 21 studies provided datasets that we analysed. We assessed 67 tests (at three cut-offs for each continuous outcome) for diagnostic accuracy of water-loss dehydration (primary target condition) and of current dehydration (secondary target condition).Only three tests showed any ability to diagnose water-loss dehydration (including both impending and current water-loss dehydration) as stand-alone tests: expressing fatigue (sensitivity 0.71 (95% CI 0.29 to 0.96), specificity 0.75 (95% CI 0.63 to 0.85), in one study with 71 participants, but two additional studies had lower sensitivity); missing drinks between meals (sensitivity 1.00 (95% CI 0.59 to 1.00), specificity 0.77 (95% CI 0.64 to 0.86), in one study with 71 participants) and BIA resistance at 50 kHz (sensitivities 1.00 (95% CI 0.48 to 1.00) and 0.71 (95% CI 0.44 to 0.90) and specificities of 1.00 (95% CI 0.69 to 1.00) and 0.80 (95% CI 0.28 to 0.99) in 15 and 22 people respectively for two studies, but with sensitivities of 0.54 (95% CI 0.25 to 0.81) and 0.69 (95% CI 0.56 to 0.79) and specificities of 0.50 (95% CI 0.16 to 0.84) and 0.19 (95% CI 0.17 to 0.21) in 21 and 1947 people respectively in two other studies). In post-hoc ROC plots drinks intake, urine osmolality and axillial moisture also showed limited diagnostic accuracy. No test was consistently useful in more than one study.Combining two tests so that an individual both missed some drinks between meals and expressed fatigue was sensitive at 0.71 (95% CI 0.29 to 0.96) and specific at 0.92 (95% CI 0.83 to 0.97).There was sufficient evidence to suggest that several stand-alone tests often used to assess dehydration in older people (including fluid intake, urine specific gravity, urine colour, urine volume, heart rate, dry mouth, feeling thirsty and BIA assessment of intracellular water or extracellular water) are not useful, and should not be relied on individually as ways of assessing presence or absence of dehydration in older people.No tests were found consistently useful in diagnosing current water-loss dehydration.

AUTHORS' CONCLUSIONS

There is limited evidence of the diagnostic utility of any individual clinical symptom, sign or test or combination of tests to indicate water-loss dehydration in older people. Individual tests should not be used in this population to indicate dehydration; they miss a high proportion of people with dehydration, and wrongly label those who are adequately hydrated.Promising tests identified by this review need to be further assessed, as do new methods in development. Combining several tests may improve diagnostic accuracy.

Validation analysis of a geriatric dehydration screening tool in community-dwelling and institutionalized elderly people

Dehydration is common among elderly people. The aim of this study was to perform validation analysis of a geriatric dehydration-screening tool (DST) in the assessment of hydration status in elderly people. This tool was based on the DST proposed by Vivanti et al., which is composed by 11 items (four physical signs of dehydration and seven questions about thirst sensation, pain and mobility), with four questions extra about drinking habits. The resulting questionnaire was evaluated in a convenience sample comprising institutionalized (n = 29) and community-dwelling (n = 74) elderly people. Urinary parameters were assessed (24-h urine osmolality and volume) and free water reserve (FWR) was calculated. Exploratory factor analysis was used to evaluate the scale’s dimensionality and Cronbach’s alpha was used to measure the reliability of each subscale. Construct’s validity was tested using linear regression to estimate the association between scores in each dimension and urinary parameters. Two factors emerged from factor analysis, which were named “Hydration Score” and “Pain Score”, and both subscales showed acceptable reliabilities. The “Hydration Score” was negatively associated with 24-h urine osmolality in community-dwelling; and the “Pain Score” was negatively associated with 24-h urine osmolality, and positively associated with 24-h urine volume and FWR in institutionalized elderly people.

Is this elderly patient dehydrated? Diagnostic accuracy of hydration assessment using physical signs, urine, and saliva markers

OBJECTIVES

Dehydration in older adults contributes to increased morbidity and mortality during hospitalization. As such, early diagnosis of dehydration may improve patient outcome and reduce the burden on healthcare. This prospective study investigated the diagnostic accuracy of routinely used physical signs, and noninvasive markers of hydration in urine and saliva.

DESIGN

Prospective diagnostic accuracy study.

SETTING

Hospital acute medical care unit and emergency department.

PARTICIPANTS

One hundred thirty older adults [59 males, 71 females, mean (standard deviation) age = 78 (9) years].

MEASUREMENTS

Participants with any primary diagnosis underwent a hydration assessment within 30 minutes of admittance to hospital. Hydration assessment comprised 7 physical signs of dehydration [tachycardia (>100 bpm), low systolic blood pressure (<100 mm Hg), dry mucous membrane, dry axilla, poor skin turgor, sunken eyes, and long capillary refill time (>2 seconds)], urine color, urine specific gravity, saliva flow rate, and saliva osmolality. Plasma osmolality and the blood urea nitrogen to creatinine ratio were assessed as reference standards of hydration with 21% of participants classified with water-loss dehydration (plasma osmolality >295 mOsm/kg), 19% classified with water-and-solute-loss dehydration (blood urea nitrogen to creatinine ratio >20), and 60% classified as euhydrated.

RESULTS

All physical signs showed poor sensitivity (0%-44%) for detecting either form of dehydration, with only low systolic blood pressure demonstrating potential utility for aiding the diagnosis of water-and-solute-loss dehydration [diagnostic odds ratio (OR) = 14.7]. Neither urine color, urine specific gravity, nor saliva flow rate could discriminate hydration status (area under the receiver operating characteristic curve = 0.49-0.57, P > .05). In contrast, saliva osmolality demonstrated moderate diagnostic accuracy (area under the receiver operating characteristic curve = 0.76, P < .001) to distinguish both dehydration types (70% sensitivity, 68% specificity, OR = 5.0 (95% confidence interval 1.7-15.1) for water-loss dehydration, and 78% sensitivity, 72% specificity, OR = 8.9 (95% confidence interval 2.5-30.7) for water-and-solute-loss dehydration).

CONCLUSIONS

With the exception of low systolic blood pressure, which could aid in the specific diagnosis of water-and-solute-loss dehydration, physical signs and urine markers show little utility to determine if an elderly patient is dehydrated. Saliva osmolality demonstrated superior diagnostic accuracy compared with physical signs and urine markers, and may have utility for the assessment of both water-loss and water-and-solute-loss dehydration in older individuals. It is particularly noteworthy that saliva osmolality was able to detect water-and-solute-loss dehydration, for which a measurement of plasma osmolality would have no diagnostic utility.

[Efficacy of the subcutaneous route compared to intravenous hydration in the elderly hospitalised patient: a randomised controlled study]

INTRODUCTION

The subcutaneous (SC) route has recently emerged as a rehydration method with potential advantages in the geriatric population. Nevertheless, little is known about its application during hospitalization. The objective of the present study is to evaluate the subcutaneous non-inferiority efficacy in hydration against the intravenous (IV) route in elderly patients with dehydration.

MATERIAL AND METHODS

A prospective, randomized and controlled interventional trial of patients 65 years and older admitted to an Acute Geriatric Unit with mild to moderate dehydration and oral intolerance, evaluating the non-inferiority of subcutaneous fluid therapy versus the intravenous route. The intervention consisted of the administration of up to 1.5 l/day/route for 72 hours subcutaneous vs. intravenous, evaluating the variations in biochemical parameters (urea, creatinine, osmolarity), clinical outcome, and route related complications.

RESULTS

Sixty seven patients completed the study (34 SC, age 86.4 ± 8.5 years, 41% women, vs. 33 IV, 84.3 ± 6.6, 54.5% women, with no significant differences). The amount of fluid administered per day by route was 1.320 ml ± 400 SC vs. 1.480 ml ± 340 IV, P = .092. During follow similar reductions were observed between groups without any statistical significance, with mean differences pre-postintervention of urea (49.6 ± 52.3 SC vs. 50.3 ± 52.3 IV, P=.96); creatinine (0.68 ± 0.66 SC vs. 0.60 ± 0.49 IV, P=.58), and osmolarity (15.6 ± 24.4 SC vs. 21.1 ± 31 IV, P=.43). Fewer catheter extraction episodes were observed in the SC group, which also was the group most prone to peri-clysis edema.

CONCLUSIONS

The efficacy of subcutaneous rehydration in elderly hospitalized patients with mild-moderate dehydration is not inferior to that obtained intravenously, and may even have additional advantages.

The diagnostic accuracy of multi-frequency bioelectrical impedance analysis in diagnosing dehydration after stroke

Background

Non-invasive methods for detecting water-loss dehydration following acute stroke would be clinically useful. We evaluated the diagnostic accuracy of multi-frequency bioelectrical impedance analysis (MF-BIA) against reference standards serum osmolality and osmolarity.

Material/Methods

Patients admitted to an acute stroke unit were recruited. Blood samples for electrolytes and osmolality were taken within 20 minutes of MF-BIA. Total body water (TBW%), intracellular (ICW%) and extracellular water (ECW%), as percentages of total body weight, were calculated by MF-BIA equipment and from impedance measures using published equations for older people. These were compared to hydration status (based on serum osmolality and calculated osmolarity). The most promising Receiver Operating Characteristics curves were plotted.

Results

27 stroke patients were recruited (mean age 71.3, SD10.7). Only a TBW% cut-off at 46% was consistent with current dehydration (serum osmolality >300 mOsm/kg) and TBW% at 47% impending dehydration (calculated osmolarity ≥295–300 mOsm/L) with sensitivity and specificity both >60%. Even here diagnostic accuracy of MF-BIA was poor, a third of those with dehydration were wrongly classified as hydrated and a third classified as dehydrated were well hydrated. Secondary analyses assessing diagnostic accuracy of TBW% for men and women separately, and using TBW as a percentage of lean body mass showed some promise, but did not provide diagnostically accurate measures across the population.

Conclusions

MF-BIA appears ineffective at diagnosing water-loss dehydration after stroke and cannot be recommended as a test for dehydration, but separating assessment by sex, and using TBW as a percentage of lean body weight may warrant further investigation.

Advances in electronic-nose technologies developed for biomedical applications

The research and development of new electronic-nose applications in the biomedical field has accelerated at a phenomenal rate over the past 25 years. Many innovative e-nose technologies have provided solutions and applications to a wide variety of complex biomedical and healthcare problems. The purposes of this review are to present a comprehensive analysis of past and recent biomedical research findings and developments of electronic-nose sensor technologies, and to identify current and future potential e-nose applications that will continue to advance the effectiveness and efficiency of biomedical treatments and healthcare services for many years. An abundance of electronic-nose applications has been developed for a variety of healthcare sectors including diagnostics, immunology, pathology, patient recovery, pharmacology, physical therapy, physiology, preventative medicine, remote healthcare, and wound and graft healing. Specific biomedical e-nose applications range from uses in biochemical testing, blood-compatibility evaluations, disease diagnoses, and drug delivery to monitoring of metabolic levels, organ dysfunctions, and patient conditions through telemedicine. This paper summarizes the major electronic-nose technologies developed for healthcare and biomedical applications since the late 1980s when electronic aroma detection technologies were first recognized to be potentially useful in providing effective solutions to problems in the healthcare industry.