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1996 ◽  
Vol 17 (11) ◽  
pp. 395-403
Author(s):  
Nicholas Jospe ◽  
Gilbert Forbes
Keyword(s):  
Total Body Water ◽  
Extracellular Fluid ◽  
Body Fluids ◽  
Body Water ◽  
The Body ◽  
Electrolyte Balance ◽  
Electrolyte Disorders ◽  
Core Concepts ◽  
Body Fluid Volume ◽  
Total Body

Changes in volume and composition of body fluids due to disorders of fluid and electrolyte balance cause various common clinical illnesses. The rationale for reviewing the diagnosis and management of fluid and electrolyte disorders was eloquently denoted by Dr Altemeier, when he suggested that this knowledge belongs among the core concepts needed by the "keepers of the gates," that is, primary care pediatricians.1 In the body, homeostasis is maintained by the coordinated action of behavioral, hormonal, renal, and vascular adaptations to volume and osmotic changes. These core issues have been outlined in a previous article in this journal by Dr Hellerstein, and the current article proceeds from that discussion.2 Following introductory comments about body fluid volume and composition, we provide an overview of some of the etiologies of the disorders of volume, tonicity, and composition of body fluids and of the therapy to correct these disorders. Sodium, Osmolality, and the Volume of Body Fluids Total body water, which is 55% to 72% of body mass, varies with sex, age, and fat content and is distributed between the intracellular and extracellular spaces. The extracellular fluid (ECF), which comprises about one third of total body water, includes the intravascular plasma fluid and the extravascular interstitial fluid.

Bioelectrical Impedance Analysis: Clinical Tool in Assessing Total Body Water and Thoracic Fluid

1995 ◽  
Vol 18 (11) ◽  
pp. 693-699 ◽  
Author(s):  
P.M.J.M. De Vries ◽  
A. Vonk Noordegraaf ◽  
B.J.M. Van Der Meer ◽  
H.H. Woltjer ◽  
J.P.P.M. De Vries
Keyword(s):  
Total Body Water ◽  
Bioelectrical Impedance Analysis ◽  
Extracellular Fluid ◽  
Bioelectrical Impedance ◽  
Impedance Analysis ◽  
Body Fluids ◽  
Body Water ◽  
The Body ◽  
Pronounced Increase ◽  
Total Body

Bioelectrical impedance analysis forms a non-invasive tool for detection of body fluids. Total body measurement gives total body water (TBW) and, in case of multi-frequency analysis, of intra- and extracellular fluid volume. The thoracic approach measures thoracic fluid (TF). The set-up of both techniques is discussed. An overview is given of the clinical usefulness of the total body technique to monitor fluid changes and the process of refill during hemodialysis and to detect dry weight. The simultaneous measurement of TBW and TF was applied to obtain a more detailed picture of the body fluids. In a group of healty subjects the age dependency of both variables was shown. During hemodialyss TBW and TF showed a major and comparable decrease. Fluid retention during cardiac surgery led to a slightly more pronounced increase of TF than of TBW. The combination of both impedance techniques offers clinicians a means to monitor alterations in fluid status in patients in more detail.

scholarly journals The Use of Infrared Spectrophotometry for Measuring Body Water Spaces

1999 ◽  
Vol 45 (7) ◽  
pp. 1077-1081 ◽  
Author(s):  
Graham Jennings ◽  
Leslie Bluck ◽  
Antony Wright ◽  
Marinos Elia
Keyword(s):  
Sample Preparation ◽  
Total Body Water ◽  
Biological Fluids ◽  
Deuterium Oxide ◽  
Body Water ◽  
The Body ◽  
Infrared Spectrophotometry ◽  
Significant Difference ◽  
Total Body ◽  
Novel Algorithm

Abstract Background: The conventional method of measuring total body water by the deuterium isotope dilution method uses gas isotope ratio mass spectrometry (IRMS), which is both expensive and time-consuming. We investigated an alternative method, using Fourier transform infrared spectrophotometry (FTIR), which uses less expensive instrumentation and requires little sample preparation. Method: Total body water measurements in human subjects were made by obtaining plasma, saliva, and urine samples before and after oral dosing with 1.5 mol of deuterium oxide. The enrichments of the body fluids were determined from the FTIR spectra in the range 1800–2800 cm−1, using a novel algorithm for estimation of instrumental response, and by IRMS for comparison. Results: The CV (n = 5) for repeat determinations of deuterium oxide in biological fluids and calibrator solutions (400–1000 μmol/mol) was found to be in the range 0.1–0.9%. The use of the novel algorithm instead of the integration routines supplied with the instrument gave at least a threefold increase in precision, and there was no significant difference between the results obtained with FTIR and those obtained with IRMS. Conclusion: This improved infrared method for measuring deuterium enrichment in plasma and saliva requires no sample preparation, is rapid, and has potential value to the clinician.

scholarly journals The impact of total body water on breath alcohol calculations

2020 ◽  
Vol 132 (17-18) ◽  
pp. 535-541
Author(s):  
Gregor S. Reiter ◽  
Markus Boeckle ◽  
Christian Reiter ◽  
Monika H. Seltenhammer
Keyword(s):  
Total Body Water ◽  
Elimination Rate ◽  
Test Group ◽  
Body Water ◽  
The Body ◽  
Blood Alcohol ◽  
Individual Parameter ◽  
Breath Alcohol ◽  
Total Body ◽  
The Impact

Summary Due to a legislative amendment in Austria to determine breath alcohol (BrAC) instead of blood alcohol (BAC) in connection with traffic offences, many results of blood alcohol calculations were simply converted using distinct conversion factors. In Austria, the transformation of BAC to BrAC was carried out by using a factor of 1:2000, which, however, is commonly known to be too low. Noticing the great demand for a calculation method that is not exclusively based on blood alcohol, a formula for calculating breath alcohol based on blood alcohol was published in 1989, but in which the body surface area (BSA) was considered the most important influencing variable. In order to refine this new method, a liquor intake experiment was conducted combined with measurements of total body water (TBW) as an additional variable, using hand to foot bioelectrical impedance assessment (BIA). The test group comprised 37 men and 40 women to evaluate the accuracy of TBW and BSA as an individual parameter for alcohol concentration. The correlation coefficient of BrAC with TBW was constantly higher than with BSA (maximum = 0.921 at 1 h and 45 min after cessation of alcohol intake). These results are valid for both men and women as well as in a gender independent calculation. Hence, for an accurate back calculation of BrAC adjusted values of eliminations rates had to be found. This study describes mean elimination rates of BrAC for both men (0.065 ± 0.011 mg/L h−1) and women (0.074 ± 0.017 mg/L h−1). As previously shown women displayed a significantly higher elimination rate than men (p = 0.006).

Total body water and the exchangeable hydrogen. I. Theoretical calculation of nonaqueous exchangeable hydrogen in man

1977 ◽  
Vol 232 (1) ◽  
pp. R54-R59 ◽  
Author(s):  
J. M. Culebras ◽  
F. D. Moore
Keyword(s):  
Theoretical Calculation ◽  
Total Body Water ◽  
Body Water ◽  
The Body ◽  
Protein Conformations ◽  
Molecular Conformations ◽  
Exchangeable Hydrogen ◽  
Short Period ◽  
Total Body ◽  
Short Time

A theoretical calculation of the total nonaqueous exchangeable hydrogen in protein, carbohydrates, and fat in man has been made. It shows that of the total exchangeable hydrogen in the body 5.22% is located in biochemical components, soluble in body water, containing hydrogen that is exchangeable with the isotope. This value represents a maximum upward distortion of total body water measurements by isotope dilution, due to the maximum possible exchangeability in these molecular conformations. From comparative measurements reported in the literature it is clear that this maximum is not achieved during the short period of time during which tritium-dilution studies are performed. It is the authors' belief that the hard-to-exchange amide hydrogens described by Blout in the protein conformations account for this failure of the isotope to achieve complete exchange in the short time allowed.

scholarly journals Measuring the body composition of elderly subjects: a comparison of methods

1994 ◽  
Vol 72 (1) ◽  
pp. 33-44 ◽  
Author(s):  
J. J. Reilly ◽  
L. A. Murray ◽  
J. Wilson ◽  
J. V. G. A. Durnin
Keyword(s):  
Body Composition ◽  
Total Body Water ◽  
Body Water ◽  
The Body ◽  
Practical Significance ◽  
Elderly Subjects ◽  
Younger Adults ◽  
Individual Level ◽  
Total Body ◽  
The Individual

There is a paucity of data on differences between methods for the assessment of body composition in elderly subjects. Studies on younger adults suggest that such differences are of some practical significance at the individual level. In the present study the following methods of estimating percentage body fatness (BF%) were compared in healthy elderly men and women (mean age 70 (SD 6) years: densitometry; skinfold thickness; total body water; bioelectrical impedance (BIA) using an age-specific predictive equation and the manufacturers' equation; body mass index (BMI). Though BF% estimates from the various methods tended to be highly correlated with those from densitometry and with each other, differences between methods at the individual level were marked. In particular, the age-specific equations based on BMI and BIA systematically overestimated BF% relative to the other methods. Biases between BF% estimates derived from densitometry, skinfolds, BIA (manufacturers' equation) and total body water were less marked, indicating little evidence of systematic differences between these methods in elderly subjects. Individual differences between methods were slightly greater than those reported in some studies of younger adults, but this may be of little practical significance, and may be considered inevitable in view of variability between and within subjects in the extent to which the underlying assumptions of these two-component methods are met in elderly subjects.

Time course and magnitude of changes in total body water, extracellular fluid volume, intracellular fluid volume and plasma volume during submaximal exercise and recovery in horses

2004 ◽  
Vol 1 (2) ◽  
pp. 131-139 ◽  
Author(s):  
Michael I Lindinger ◽  
Gloria McKeen ◽  
Gayle L Ecker
Keyword(s):  
Plasma Volume ◽  
Total Body Water ◽  
Time Course ◽  
Extracellular Fluid ◽  
Submaximal Exercise ◽  
Body Water ◽  
Fluid Volume ◽  
Extracellular Fluid Volume ◽  
Intracellular Fluid ◽  
Total Body

AbstractThe purpose of the present study was to determine the time course and magnitude of changes in extracellular and intracellular fluid volumes in relation to changes in total body water during prolonged submaximal exercise and recovery in horses. Seven horses were physically conditioned over a 2-month period and trained to trot on a treadmill. Total body water (TBW), extracellular fluid volume (ECFV) and plasma volume (PV) were measured at rest using indicator dilution techniques (D2O, thiocyanate and Evans Blue, respectively). Changes in TBW were assessed from measures of body mass, and changes in PV and ECFV were calculated from changes in plasma protein concentration. Horses exercised by trotting on a treadmill for 75–120 min incurred a 4.2% decrease in TBW. During exercise, the entire decrease in TBW (mean±standard error: 12.8±2.0 l at end of exercise) could be attributed to the decrease in ECFV (12.0±2.4 l at end of exercise), such that there was no change in intracellular fluid volume (ICFV; 0.9±2.4 l at end of exercise). PV decreased from 22.0±0.5 l at rest to 19.8±0.3 l at end of exercise and remained depressed (18–19 l) during the first 2 h of recovery. Recovery of fluid volumes after exercise was slow, and characterized by a further transient loss of ECFV (first 30 min of recovery) and a sustained increase in ICFV (between 0.5 and 3.5 h of recovery). Recovery of fluid volumes was complete by 13 h post exercise. It is concluded that prolonged submaximal exercise in horses favours net loss of fluid from the extracellular fluid compartment.

Estimation of body water and fat in cattle using tritiated water space and live weight with particular reference to the influence of breed

1983 ◽  
Vol 101 (2) ◽  
pp. 257-264 ◽  
Author(s):  
P. R. N. Chigaru ◽  
D. H. Holness
Keyword(s):  
Body Fat ◽  
Total Body Water ◽  
Tritiated Water ◽  
Live Weight ◽  
Close Relation ◽  
Body Water ◽  
The Body ◽  
Metabolizable Energy ◽  
Complete Diet ◽  
Total Body

SUMMARYThe body composition of 18 each of Mashona, Afrikaner and Hereford heifers was measured at the beginning and after 16 and 32 weeks of the experiment. The heifers not slaughtered at the beginning of the experiment were fed a complete diet containing 132 g crude protein and 12·0 MJ metabolizable energy/kg dry matter. Before slaughter, the animals were deprived of food and water for 24 h. Each animal was infused with 1 mCi of tritiated water (TOH) in order to measure total body water (TBW) and to estimate body fat.The growth rate of the three breeds of heifers was similar despite differences in age and initial live weight. Both TBW and fat proportions, however, differed significantly (P < 0·01) between slaughter stages for each breed and between breeds at each slaughter stage. At the first, second and final slaughter stages the proportions of TBW were: 68·0, 59·4 and 54·5% for Mashona; 70·;5, 64·3 and 58·3% for Afrikaner and 65·3, 57·6 and 46·2% for Hereford heifers respectively. The corresponding proportions of body fat were: 10·2, 18·4 and 24·2% for Mashona; 6·6, 12·0 and 20·0% for Afrikaner and 13·7, 20·8 and 25·8% for Hereford heifers respectively.There was a close relation between empty body weight and live weight at slaughter which was not influenced by breed. Both TBW and fat were estimated more accurately when TOH space and live weight were used jointly. However, the slopes of the prediction equations for each breed were significantly different (P < 0·05) in the case of both total body water and fat. It was necessary to use separate equations for each breed in order to predict either body water or fat. The significance of these findings for the estimation of body fat in live cattle is discussed.

scholarly journals Extracellular fluid and total body water changes in neonates undergoing extracorporeal membrane oxygenation

1992 ◽  
Vol 27 (8) ◽  
pp. 1003-1008 ◽  
Author(s):  
Harry L. Anderson ◽  
Arnold G. Coran ◽  
Robert A. Drongowski ◽  
Hyun J. Ha ◽  
Robert H. Bartlett
Keyword(s):  
Extracorporeal Membrane Oxygenation ◽  
Total Body Water ◽  
Extracellular Fluid ◽  
Body Water ◽  
Membrane Oxygenation ◽  
Total Body
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