Research - Fluid Management in Critical Care

This study was undertaken to assess the comparability of body water compartment estimates in healthy volunteers using single and dual frequency BIA with established reference methods of tritium and NaBr dilution.

Measurements of plasma volume with ¹²⁵I human serum albumin, extracellular water (ECW) with ⁸²Br^-, and total body water (TBW) with ³H₂0 were made on 16 postoperative patients, 15 depleted patients, and three control subjects.

Chronically ventilated patients have nutritional modifications during their hospital stay. These parameters may influence the weaning from the ventilator process. Bio impedance technique could assess in a repetitive way the body composition of these patients and their ability to be weaned.

Bioimpedance (Ω) analysis (BIA) provides a potential measure of body water (1). BIA may predict decompensation in systolic heart failure (2). We tested the utility of BIA in assessing the acute response to intravenous furosemide (ivF) in pulmonary oedema.

The ability of bedside multifrequency bioelectrical impedance analysis to monitor fluid disturbance and predict patients at risk of developing oedema after major surgery was assessed.

Critically ill patients retain fluid, up to 30 litres and more. In individuals ill for prolonged periods it is virtually impossible to assess fluid balance accurately, but as a non-invasive method of doing so bioimpedance has its obvious attractions. We have previously described the use of single frequency (50kHz) impedance to assess body water in these individuals but the interindividual errors were too large to be acceptable (Foley et al. 1998). The correlation ® between conductace (height²/impedance) at multiple frequencies (5-500 kHz; Multiscan 5000, Bodystat Ltd, Douglas, Isle of Man) and body water (measured using deuterium analysed by Continuous Flow Isotope Ratio Mass Spectrometry following equilibration with H2) was investigated in ten critically ill patients; in three patients multiple measurements were made, in two on four occasions and in one on six.

Measurements of extracellular and total body water provide useful information on the nutritional status of surgical patients and may be estimated from whole-body bio-impedance measurements at different frequencies. Resistance and reactance were measured at 50 frequencies from 5kHz to 1MHz in 29 surgical patients (17 males, 12 females) with a wide range of extracellular to total body water ratios.

Clinicians lack well-validated, non-invasive, objective tools to guide volume management in the post-resuscitative period. Bioimpedance analysis (BIA) represents a novel method for guiding fluid management. We studied the relationship of BIA vector length (VL), an indicator of volume status, to the need for mechanical ventilation in patients with sepsis.

The aim of this study was to investigate the association of fluid overload, measured by bioelectrical impedance vector analysis (BIVA) and also by accumulated fluid balance, with 30-day mortality rates in patients admitted to the emergency department (ED).

Myotonic dystrophy type 1 (DM1) is an inherited muscle disorder characterized by slowly progressive weakness due to muscle degeneration. The Muscular Impairment Rating Scale (MIRS) is validated to assess clinical muscle severity of patients with DM1, although the scale is not sensitive enough to assess disease progression in time intervals fit for clinical trials. The aim of this study was to analyze bioelectrical whole body and arm segmental parameters in patients with DM1 to explore a correlation between bioelectrical impedance analysis (BIA) parameters and disease stage.