scholarly journals Characteristics of Intracellular and Extracellular Fluid Ratio for the Varying Body Impedances in Fixed Total Body Fluid

Author(s):  
JungHun Choi

A bioelectrical impedance analysis is a proven method to measure body composition in clinical situations. It uses the relation between the body fluid and the impedances in a variety of frequencies. A body model can be simplified as a parallel combination of a capacitor and two resistors which represent a cell membrane, Intracellular Fluid (ICF), and Extracellular Fluid (ECF). Low frequency current passes through ECF and high frequency current also passes through ICF in a body. A Cole-Cole plot is a graphical interpretation of the path of impedances and each axis represents resistance and reactance with variable frequencies. A high value of resistance in a horizontal axis is a resistance value of ECF and a low value of resistance at a high frequency presents ICF. Interpolation technique is needed to find out the exact cross-point between impedance values and the horizontal axis. The two estimated impedance values are used to derive Total Body Water (TBW), ICF, ECF, Fat Free Mass (FFM), and Fat Mass (FM) from various published equations [1]. Minimizing the possible error of fluid volume assessment and accurate prediction of fluid status in a human body is essential for appropriate therapy. Different techniques of fluid status assessment in a human body can be applicable, such as physical examination, orthostatic vital signs, blood volume measurement, acoustic cardiograph, chest radiography, and thoracic ultrasonography [2]. In this study, a bioelectrical impedance spectroscopy device and simple body models were used to collect data such as TBW, ICF, ECF, FM, and FFM. The ratio between ICF and ECF was investigated for the same values of TBW, FM, and FFM by varying impedance values.

Author(s):  
Robert G. Hahn

The maintenance of body fluid homeostasis is an essential task in perioperative care. Body fluid volumes are tightly controlled by the nervous system, by hormones, and by the kidneys. All these systems are affected by anaesthesia and surgery in ways that must be appreciated by the anaesthetist. Administration of infusion fluids is the key tool to prevent major derangements of the body fluid volumes during before, during, and after surgery. By varying its composition, an infusion fluid can be made to selectively expand or shrink a body fluid compartment. The total osmolality determines whether the infused volume distributes over the total body water or over the extracellular fluid volume, or even attracts fluid from intracellular space. Infusion fluid is the first-line tool in the management of the vasodilation that is induced by both general and regional anaesthesia. Fluids are also an essential component in the treatment of haemorrhage, in which a reduction in arterial pressure implies that 20% of the blood volume has been lost. Capillary refill restores the blood volume, but too slowly to prevent haemorrhagic shock. In this situation, prompt intravenous fluid therapy is life-saving. Electrolyte derangements may be induced by disease and/or medication. The most essential ones to consider during anaesthesia are sodium, potassium, calcium, and bicarbonate.


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

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.


1996 ◽  
Vol 81 (1) ◽  
pp. 105-116 ◽  
Author(s):  
C. S. Leach ◽  
C. P. Alfrey ◽  
W. N. Suki ◽  
J. I. Leonard ◽  
P. C. Rambaut ◽  
...  

The fluid and electrolyte regulation experiment with seven subjects was designed to describe body fluid, renal, and fluid regulatory hormone responses during the Spacelab Life Sciences-1 (9 days) and -2 (14 days) missions. Total body water did not change significantly. Plasma volume (PV; P < 0.05) and extracellular fluid volume (ECFV; P < 0.10) decreased 21 h after launch, remaining below preflight levels until after landing. Fluid intake decreased during weightlessness, and glomerular filtration rate (GFR) increased in the first 2 days and on day 8 (P < 0.05). Urinary antidiuretic hormone (ADH) excretion increased (P < 0.05) and fluid excretion decreased early in flight (P < 0.10). Plasma renin activity (PRA; P < 0.10) and aldosterone (P < 0.05) decreased in the first few hours after launch; PRA increased 1 wk later (P < 0.05). During flight, plasma atrial natriuretic peptide concentrations were consistently lower than preflight means, and urinary cortisol excretion was usually greater than preflight levels. Acceleration at launch and landing probably caused increases in ADH and cortisol excretion, and a shift of fluid from the extracellular to the intracellular compartment would account for reductions in ECFV. Increased permeability of capillary membranes may be the most important mechanism causing spaceflight-induced PV reduction, which is probably maintained by increased GFR and other mechanisms. If the Gauer-Henry reflex operates during spaceflight, it must be completed within the first 21 h of flight and be succeeded by establishment of a reduced PV set point.


2021 ◽  
Vol 17 (7) ◽  
pp. 20-23
Author(s):  
O.M. Klygunenko ◽  
O.О. Marzan

Background. Preeclampsia in pregnant women is a threatening condition that causes significant water imbalance, particularly hyperhydration of the extracellular fluid compartment. The condition is the result of the main pathogenetic processes — endothelial dysfunction and the subsequent development of hypoproteinemia. The changes can be detected by measuring body water compartments. Objective: to investigate the effect of a standard intensive care on the body water compartment indicators in women with moderate to severe preeclampsia. Materials and methods. Ninety patients divided into three groups were examined: non-pregnant healthy women, pregnant women with healthy pregnancy, and women whose pregnancy was complicated by moderate to severe preeclampsia. Body water compartments were measured by non-invasive bioelectrical impedance analysis. Results. Pregnancy complicated by preeclampsia is accompanied by an increase in total fluid volume at 34–40 weeks due to an increase in both the extracellular and intracellular water compartments, but with a predominance of the extracellular compartment. By the 7th day of the postpartum period, there is a tendency to decrease the total fluid volume, however, interstitial and intracellular edema can be still observed. Conclusions. The results of the bioelectrical impe-dance analysis of the body water compartments show that additional methods of treatment are needed to correct the body water compartments in women with preeclampsia.


Author(s):  
Lan Huang ◽  
Dan Shao ◽  
Yan Wang ◽  
Xueteng Cui ◽  
Yufei Li ◽  
...  

Abstract Empowered by the advancement of high-throughput bio technologies, recent research on body-fluid proteomes has led to the discoveries of numerous novel disease biomarkers and therapeutic drugs. In the meantime, a tremendous progress in disclosing the body-fluid proteomes was made, resulting in a collection of over 15 000 different proteins detected in major human body fluids. However, common challenges remain with current proteomics technologies about how to effectively handle the large variety of protein modifications in those fluids. To this end, computational effort utilizing statistical and machine-learning approaches has shown early successes in identifying biomarker proteins in specific human diseases. In this article, we first summarized the experimental progresses using a combination of conventional and high-throughput technologies, along with the major discoveries, and focused on current research status of 16 types of body-fluid proteins. Next, the emerging computational work on protein prediction based on support vector machine, ranking algorithm, and protein–protein interaction network were also surveyed, followed by algorithm and application discussion. At last, we discuss additional critical concerns about these topics and close the review by providing future perspectives especially toward the realization of clinical disease biomarker discovery.


1985 ◽  
Vol 249 (2) ◽  
pp. E227-E233 ◽  
Author(s):  
A. H. Beddoe ◽  
S. J. Streat ◽  
G. L. Hill

It is widely believed that increased hydration of the fat-free body accompanies most major disease processes as a result of contraction of the body cell mass and expansion of the extracellular fluid. Measurements of total body water (TBW) and total body nitrogen in 68 normal volunteers and 95 surgical ward patients presenting for intravenous nutrition have been used to derive ratios of TBW to fat-free mass (TBW:FFM) and protein indices (PI), where PI is defined as the ratio of measured total body protein to predicted TBP. Mean values of PI were 1.009 +/- 0.116 (SD) and 0.783 +/- 0.152 in the normal and patient groups, respectively, corresponding to mean TBW:FFM ratios of 0.719 +/- 0.016 and 0.741 +/- 0.029. However, 48 patients had normal TBW:FFM despite having lost 15% of body protein. A theoretical model of body composition changes in catabolic illness is presented, which is in accord with the patient data, demonstrating that TBW:FFM does not necessarily increase in catabolic illness and that the ratio masks underlying shifts in body fluid compartments.


1988 ◽  
Vol 65 (1) ◽  
pp. 318-324 ◽  
Author(s):  
H. Nose ◽  
G. W. Mack ◽  
X. R. Shi ◽  
E. R. Nadel

To investigate the influence of [Na+] in sweat on the distribution of body water during dehydration, we studied 10 volunteer subjects who exercised (40% of maximal aerobic power) in the heat [36 degrees C, less than 30% relative humidity (rh)] for 90-110 min to produce a dehydration of 2.3% body wt (delta TW). After dehydration, the subjects rested for 1 h in a thermoneutral environment (28 degrees C, less than 30% rh), after which time the changes in the body fluid compartments were assessed. We measured plasma volume, plasma osmolality, and [Na+], [K+], and [Cl-] in plasma, together with sweat and urine volumes and their ionic concentrations before and after dehydration. The change in the extracellular fluid space (delta ECF) was estimated from chloride distribution and the change in the intracellular fluid space (delta ICF) was calculated by subtracting delta ECF from delta TW. The decrease in the ICF space was correlated with the increase in plasma osmolality (r = -0.74, P less than 0.02). The increase in plasma osmolality was a function of the loss of free water (delta FW), estimated from the equation delta FW = delta TW - (loss of osmotically active substance in sweat and urine)/(control plasma osmolality) (r = -0.79, P less than 0.01). Free water loss, which is analogous to "free water clearance" in renal function, showed a strongly inverse correlation with [Na+] in sweat (r = -0.97, P less than 0.001). Fluid movement out of the ICF space attenuated the decrease in the ECF space.(ABSTRACT TRUNCATED AT 250 WORDS)


1997 ◽  
Vol 82 (10) ◽  
pp. 3349-3355 ◽  
Author(s):  
Y. J. H. Janssen ◽  
P. Deurenberg ◽  
F. Roelfsema

Abstract Due to the use of various, and mostly indirect, methods to estimate total body water (TBW) and extracellular water (ECW), there is no agreement about whether body water distribution, i.e. the ECW to TBW ratio, is normal in GH-deficient (GHD) subjects at baseline and during recombinant human GH (rhGH) treatment. We studied body water distribution in 14 patients with adult-onset GHD and in 28 healthy controls. We also investigated the effect of GH replacement therapy for 4 and 52 weeks on body water distribution. All patients started with a dose of 0.6 IU rhGH/day for the first 4 weeks. After 52 weeks, the dose varied between 0.6–1.8 IU/day. TBW and ECW were measured by dilution of deuterium and bromide, respectively. Both parameters were also estimated using multifrequency bioelectrical impedance (BIA). Patients with GHD had significantly lower ECW and TBW than healthy controls. In addition, the ECW to TBW ratio was significantly lower in GHD patients than in healthy controls. Four weeks of GH treatment significantly increased body weight, TBW, ECW, and ECW/TBW. A further increase in TBW, but not ECW, was found after 52 weeks of treatment. The mean increases in TBW and ECW from the baselines were 2.5 ± 0.3 and 2.0 ± 0.3 L, respectively. The correlation coefficient and the estimated reliability between measured and estimated TBW and ECW at any time point were all high (&gt;0.91 and &gt;0.95, respectively). In general, both ECW and TBW were overestimated by multifrequency BIA in GHD adults. During treatment, the overestimation of both ECW and TBW diminished. The estimation error was correlated with the level of the body water compartment and the ratio of ECW to TBW. The estimated change in ECW with rhGH treatment was underestimated by multifrequency BIA. We conclude that GHD adults have lower ECW and TBW and a lower ECW to TBW ratio, as measured by dilution techniques. The ECW to TBW ratio can be normalized within 4 weeks of rhGH treatment at a dose of 0.6 IU/day. Finally, we conclude that multifrequency impedance measurements do not give valid estimates of body water compartments in the follow-up of patients with GHD.


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