Rapid measurement of total body water to facilitate clinical decision making in hospitalized elderly patients.
BACKGROUND
Bioelectrical impedance analysis (BIA) is a noninvasive rapid and simple bedside technique that can be used to predict total body water (TBW), extracellular water (ECW), and intracellular water (ICW) and identify altered fluid distribution following critical illness.


METHODS
An equivalence study of BIA in 32 hospitalized elderly patients was compared with reference standard dilutional measurements of deuterated water (TBW) and sodium bromide (ECW). The results were compared with anthropometric equations commonly used to predict TBW.


RESULTS
There was variability in TBW content among the participating hospitalized elderly patients. This variability was within (+/-5 L) and the percent difference between the standard and BIA was as follows: mean (range) -4.1% (-18.5 to 11.2). BIA reliably predicted TBW and ECW in individual participants, whereas standard prediction equations uniformly over- or underestimated TBW in individuals and whole group population.


CONCLUSIONS
TBW in hospitalized elderly patients can be estimated noninvasively by bedside BIA. Standardized anthropometric equations have to be used with caution in this population.
Powers
James S
JS
Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA. james.powers@vanderbilt.edu
Choi
Leena
L
Bitting
Rhonda
R
Gupta
Nitin
N
Buchowski
Maciej
M
D000368:Aged; D000369:Aged, 80 and over; D000886:Anthropometry / Q000295:instrumentation / Q000379:methods*; D001834:Body Water; D001965:Bromides; D017666:Deuterium Oxide; D017097:Electric Impedance; D005260:Female; D015577:Geriatric Assessment / Q000379:methods*; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D010992:Plethysmography, Impedance / Q000379:methods*; D011237:Predictive Value of Tests; D011837:Radiation-Protective Agents; D015203:Reproducibility of Results; D017670:Sodium Compounds
D001965:Bromides; D011837:Radiation-Protective Agents; D017670:Sodium Compounds; D017666:Deuterium Oxide; C027938:sodium bromide