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

New horizons in the diagnosis and management of dehydration

Hydration is a fundamental aspect of clinical practice and yet it is an under-researched topic, particularly in older people, leading to many areas of uncertainty. There are two types of dehydration; hypertonic, which is a water deficit, and isotonic, which is a deficit of both water and salt. Individual clinical signs and bedside tests are poor diagnostic tools, making dehydration difficult to identify. However, the diagnostic value of a holistic clinical approach is not known. The gold-standard clinical test for dehydration is serum osmolality, but this cannot diagnose isotonic dehydration and may delay diagnosis in acute situations. Salivary osmolality point-of-care testing is a promising and rapid new diagnostic test capable of detecting both hypertonic and isotonic dehydration in older people, but further evidence to support its clinical utility is needed. Daily fluid requirements may be less than previously thought in adults, but the evidence specific to older people remains limited. Hydration via the subcutaneous route is safer and easier to initiate than the intravenous route but is limited by infusion speed and volume. Prompting older adults more frequently to drink, offering a wider selection of drinks and using drinking vessels with particular features can result in small increases in oral intake in the short-term. The ongoing clinically-assisted hydration at end of life (CHELsea II) trial will hopefully provide more evidence for the emotive issue of hydration at the end of life.

Inferior vena cava ultrasonography in the assessment of intravascular volume status and fluid responsiveness in the emergency department and intensive care unit: A critical analysis review

Rapid evaluation of intravascular volume status is vital; either excessive or limited fluid administration may result in adverse patient outcomes. In this narrative review, critical analysis of pertinent diagnostic accuracy studies is developed to delineate the role of inferior vena cava ultrasound measurements in the assessment of both intravascular volume status and fluid responsiveness in the emergency department and intensive care unit. In addition, limitations, and technical considerations of inferior vena cava ultrasound measurements as well as directions for future research are thoroughly discussed.

[Evaluation of the fluid balance in geriatric patients-What contribution can abdominal ultrasound make?]

The assessment of the fluid balance as well as the identification of hyperhydration and dehydration often represent a diagnostic challenge, especially in older patients. In principle, various diagnostic procedures and approaches are suitable for assessment of the various facets, by which such a disorder can be recognized. The contribution of abdominal ultrasound is described and evaluated in the context of the different diagnostic procedures. An overview of the current situation with respect to assessment of the vena cava is provided. In many respects there is no strict consensus concerning the thresholds of the individual measurements and the value of the different measurements. Currently, an orthograde diameter of the inferior vena cava > 2 cm is accepted as being a good indicator for hyperhydration. Less certain are analogously derived thresholds as indicators for dehydration.

Chronic Dehydration in Nursing Home Residents

Chronic dehydration mainly occurs due to insufficient fluid intake over a lengthy period of time, and nursing home residents are thought to be at high risk for chronic dehydration. However, few studies have investigated chronic dehydration, and new diagnostic methods are needed. Therefore, in this study, we aimed to identify risk factors for chronic dehydration by measuring serum osmolality in nursing home residents and also to evaluate whether examining the inferior vena cava (IVC) and determining the IVC collapsibility index (IVC-CI) by ultrasound can be helpful in the diagnosis of chronic dehydration. A total of 108 Japanese nursing home residents aged ≥65 years were recruited. IVC measurement was performed using a portable handheld ultrasound device. Fifteen residents (16.9%) were classified as having chronic dehydration (serum osmolality ≥295 mOsm/kg). Multivariate logistic regression analysis showed that chronic dehydration was associated with dementia (odds ratio (OR), 6.290; 95% confidential interval (CI), 1.270–31.154) and higher BMI (OR, 1.471; 95% CI, 1.105–1.958) but not with IVC or IVC-CI. Cognitive function and body weight of residents should be considered when establishing a strategy for preventing chronic dehydration in nursing homes.