Showing papers on "Body water published in 1975"

Method for monitoring body characteristics

Abstract: A method and apparatus for performing electrical measurement of body mutual electrical impedances to determine changes in total body water in normal and deranged states of the body. The apparatus is particularly useful in determining the progression of dialysis cases during the period when renal dialysis is being performed on the patient. The method and apparatus utilizes a special electrical circuit for measuring electrical characteristics at selected body locations. Certain electrical characteristics are measured such as the resistance, the capacitive impedance, and the total reactance of the body, and the phase angle is calculated or measured. Utilizing some of these measurements, the total body water relative to the body weight may be determined.

Salt and Water Balance

Abstract: In warm-blooded animals water makes up about 60 percent of the body weight and exists as a solution of organic and mineral substances. This water is in constant exchange with the environment as a result of periodic uptake from the gut and continual loss through the skin, respiratory passages, and kidney. Within the body the water is distributed in several more or less discrete compartments whose contents are called the “body fluids.” The anatomical boundaries separating these compartments and the differences in the solutes present in each are of fundamental biological significance.

Nutritional aspects of body water dislocations in postoperative and depleted patients.

Abstract: Measurements of plasma volume with 125I human serum albumin, extracellular water (ECW) with 82Br-minus, and total body water (TBW) with 3-H2O were made on 16 postoperative patients, 15 depleted patients, and three control subjects. Intracellular water (ICW) was calculated as the difference between TBW and ECW. The observed findings for the series as a whole showed no change in blood volume, an increase of 3.7 I in ECW, and a decrease of 1.5 I in ICW as compared to predicted values based on current weight. Compared to predicted values based on normal (pre-illness) weight, the observed body weight decreased 16% and ICW decreased 22%; this suggests that body weight consistently under-estimates the extent of nutritional depletion. Severe depletion seen in postoperative patients indicates that frequently earlier use of total parenteral nutrition would be beneficial. ICW was found to be the most reliable single index of moderate or severe nutritional depletion; errors in estimating normal values interfere with its use in mild depletion. The ratio of ECW:TBW best reflects distortion of body water composition; it is largely independent of weight, and is a more sensitive index than absolute values of ICW. Repeat measurements of body composition were made on 9 patients given total parenteral nutrition for an average period of 18 days. On the average, there was an ECW decrease of 1.8 I, a body weight increase of 2 kg, and an ICW increase of 3.2 I after parenteral nutrition. The increased ICW represents the repletion of half of the average initial deficit of 6.1 The initial ratio of ECW:TBW of 0.58 was reduced to 0.50, returning it about three-quarters of the way to the expected normal value of 0.48. Intravenous administration of 5% glucose as sole source of calories may be a factor in distortion of body water compartments.

Estimation of extravascular lung water by indicator-dilution techniques.

Abstract: • An abnormal increase in the volume of the extravascular fluid of the lungs can occur in cardiogenic pulmonary edema, the adult respiratory distress syndrome, and other situations such as the "shock lung" and the "wet lung." Knowledge of this volume can be important in assessing the threat to the patient and the efficacy of measures taken to alter hemodynamic pressures, solute concentrations, and water loads. Several extensive reviews of pulmonary edema have been published in the past few years (1-4), so the present review will focus on the measurement of extravascular lung water in vivo. Indicator-dilution techniques are emphasized, and the limitations and some possible extensions of these techniques are discussed. The clinical aspects of this measurement have recently been extensively reviewed by McCredie (5). Because water is the major constituent of the lungs and the blood and because of the nature of the measurements, the amount of water rather than the amount of "fluid" in the lungs is considered. The total water content of the lungs includes the water in the vascular volume of the lungs. This volume, however, cannot be defined precisely and can vary without accompanying changes in lung tissue water. Accordingly, another measure of lung water, "extravascular lung water," has been devised. This measure is essentially a determination of the total water content of an operationally (not anatomically or functionally) defined region of the body. The water content of that portion of the vasculature included in the determination is subtracted from the total lung water content, and the difference is the extravascular lung water content.

Hormonal and electrolyte response to exposure to 17,500 ft.

Abstract: Hormone, electrolyte, and body fluid compartment changes were studied in subjects who either spent time at 10,000 ft before flying to 17,500 ft or were premedicated with acetazolamide and flown directly to 17,500 ft. In the former group, at 10,000 ft, renin and aldosterone were not different from control. Cortisol increased significantly from 9.8 to 19.5 mug/100 ml on the third day. At 17,500 ft, renin, aldosterone and cortisol were significantly elevated on day 3 but had returned to control levels by day 5. Sodium and potassium excretion was significantly reduced at both altitudes. Total body water, extracellular and plasma volume were reduced (P less than 0.05) at 17,500 ft. Subjects pretreated with acetazolamide and flown directly to 17,500 ft had significant increases (P less than 0.001) in plasma renin, aldosterone, and cortisol levels during the first 4 days at altitude. On day 1 there was a decrease of 45% in sodium and 38% in potassium excretion. On day 4 there was a decrease of 63% and 51%, respectively. These changes are not associated with the premedication. The initial changes may reflect the immediate response to stress and alkalosis followed by a return to control levels as the body adapts to altitude.

Mastalgia and total body water.

Abstract: Total body water (TBW) was measured early and late in a menstrual cycle in 56 women, 39 of whom had breast pain. The remainder were asymphtomatic controls. Most women did not conform to the traditional view that there is a premenstrual increase in TBW. In some TBW decreased, while in others there was no change from the early cycle measurement. No TBW pattern correlated with any syndromes of breast pain or with any psychoneurotic profile.

Body composition in morbidly obese patients before and after jejunoileal bypass.

Abstract: A clinical and body compositional study has been made of 150 patients with morbid obesity and their responses to four different dimensional alterations of jejunoileal bypass. Total body potassium was estimated by measuring 40K with the whole body counter and total body water by tritiated water dilution. Body compositional data derived from these measurements were compared in the 4 groups during followup periods up to 4 years and related to clinical results. Initially, patients were two or more times overweight due to excess (60 to 65%) body fat and increased hydration (21%) of lean tissues. The 80 end-to-end jejunoileal bypass procedures of Groups 3 and 4 (30 cm jejunum to 15 or 20 cm ileum) had better weight losses and clinical results in followup were rated "good" in 60% and 81% respectively. These results were accompanied by a greater degree of improvement in body composition than was observed in the other groups under study.

Mechanisms of Hypovolaemic Thirst and Interactions between Hypovolaemia, Hyperosmolality and the Antidiuretic System

Abstract: The proposal that changes in plasma osmolality determine thirst was made first by Mayer (1900). It remained for Gilman (1937) to show that cellular dehydration, brought about by an increase in the effective osmotic pressure of the tissue fluid, is in fact an important stimulus to thirst.

Effects of dehydration on body-water distribution in desert kangaroos

Abstract: The effect of dehydration on the distribution of water in the bodies of two species of desert kangaroos, the red kangaroo Megaleia rufa and the euro Macropus robustus, has been examined. The volumes of various body-fluid compartments were determined in normally hydrated animals and then after the kangaroos had been dehydrated until body weight declined to 80% of the initial weight. The fluid compartments examined were total body water, plasma volume, intracellular volume (cellular and gut water), and extracellular volume. Both species were camel-like in their response to dehydration in that plasma volume was maintained in both species, falling by only 8.3% in red kangaroos and 7.4% in euros. The pattern of water loss from other compartments differed between species, particularly gut water loss. This compartment, which includes the large rumenlike fore stomach, contributed 56% of the total water loss of red kangaroos but only 22% of the loss from euros. The ecological implications of the preferential maintenance of gut water by the sedentary, cave-dwelling euros have been discussed.

Body weight and body water in chronic cor pulmonale.

Abstract: 1. Body weight was measured through forty consecutive illnesses in seventeen patients with oedema in association with chronic bronchitis and hypoxia. All patients were taking diuretic drugs at the time. 2. Body weight increased little as peripheral oedema and a raised jugular venous pressure appeared. The subsequent weight-loss during treatment was usually greater than the pre-treatment weight-gain. Body weight increased slowly in convalescence to equal or exceed hospital admission weight without a deterioration of general health or reappearance of oedema. 3. Total body water, exchangeable sodium and exchangeable potassium were measured in patients after treatment of the acute illness and clearance of oedema and again in six patients of the group 2–3 months later in convalescence. Total exchangeable sodium was normal or slightly reduced after treatment of oedema and in convalescence between recurrent acute illnesses. Even when gross oedema was present exchangeable sodium was substantially increased in only one of three patients studied at this stage. Total exchangeable potassium was invariably severely depressed. 4. Large changes of body tissue weight without comparable change in exchangeable sodium support previous evidence that oedema in hypoxic bronchitis is not simply a further form of congestive cardiac failure. 5. It is suggested that at least some of the tissue loss in acute exacerbations is a direct result of hypoxaemia and similar to that observed at high altitude. Part of the oedema fluid is thought to be derived from intracellular water released during dissolution of tissue matrix.

Muscle Glycogen and Electrolytes Following Exercise and Thermal Dehydration

Abstract: It is well established that a decrease in body weight of more than 2% by heat and/or exercise induced sweating causes an impairment in physical work capacity [1, 7, 17]. Studies have indicated that after a given sweat loss due to prolonged exercise the physical work capacity is more reduced than when sweating is stimulated by environmental heat stress. KozLowsxl and SALTIN [14] have demonstrated a marked difference in the distribution of body water when men reduced body weight (4%) by either exercise or thermally induced sweating. During exercise dehydration the major part of the sweating was achieved at the expense of intracellular water losses (−8,4%), whereas a similar degree of weight loss brought aboilt by inactive exposure to a hot, dry environment resulted in a significantly smaller loss of water from the intracellular compartment (−4,7%). Calculations of total body and plasma sodium, potassium and chloride changes suggested that during thermal dehydration there was a larger loss of sodium and chloride and a smaller loss of potassium from the extracellular space than during exercise dehydration. It seems possible that these variations in muscle water and electrolytes may alter the muscular excitability, thereby affecting the functional capacity of muscle.

An evaluation of the tritiated water method for estimating body water in small rodents.

Abstract: The total body water of 27 rodents (live weights less than 100 g) were estimated by a tritiated water method and by direct analysis. There was no significant difference between the values as estimated by the two methods. The 95% confidence interval for total body water as estimated by the tritiated water method was ±10% of the value estimated from direct analysis. The accuracy of the method is acceptable for most applications, however, investigators should be cognizant of the estimate error, especially when calculating other components of body composition from total body water, e.g. body fat.

Fluid balance, renal function, and blood pressure.

Abstract: After many detours in the search for the basic mechanism of hypertension, evidence now seems to corroborate the earliest concept that developed in the 1800's, namely, that hypertension almost always results from a tendency of the kidneys to retain water and salt. Animal studies show that the amount of excess body water and salt required to cause hypertension is exceedingly small, and that the hypertensive effect of the excess water and salt may not develop for days or weeks. When vascular constriciton occurs simultaneously, as occurs in the presence of large quantities of angiotensin, the blood volume may be less than normal, but even in these circumstances the fluid volume is relatively increased and is responsible for the hypertension because the vascular constrictont has decreased the capacity of the circulation to a greater extent than the decrease in blood volume.

Relationships of the Renin-Angiotensin-Aldosterone System and Sodium Balance to Blood Pressure Regulation in Chronic Renal Failure of Polycystic Kidney Disease

Abstract: In 5 patients with polycystic kidney disease and creatinine clearances ranging from 4 to 40 ml/min, relationships between changes in blood pressure, sodium balance, body fluid compartments, plasma renin activity (PRA), urinary aldosterone excretion, and plasma aldosterone concentrations were studied during periods of low, medium, and high sodium intake. Total body water (TBW), total exchangeable body sodium (TEBS), and extracellular volume (ECV) were measured by isotope dilution techniques, plasma volume with Evan's blue dye, and PRA and aldosterone by radioimmunoassay. Low sodium intake reduced kidney function, blood pressure, and serum sodium, while PRA reached its highest levels. Subsequent increases in sodium intake improved kidney function and increased blood pressure. Plasma volume increased slightly and ECV markedly, while PRA dropped to 15% of the value noted after the low sodium intake. TBW and TEBS showed inconsistent changes. Aldosterone changes correlated closely with PRA. Blood pressure showed a negative correlation with PRA, but a positive one with body weight and cumulative sodium balance, and with plasma and extracellular volumes. It is suggested that whereas renin and aldosterone are involved in the maintenance of circulatory homeostasis during sodium loss, sodium retention causes an increase in blood pressure by concomitant changes in body fluids.

Serial Measurements of Plasma Half-Lives and Urinary Excretion of Antipyrine in Low-Birth-Weight Infants

Abstract: Antipyrine has been used previously to estimate total body water in infants. In the present study, antipyrine spaces were determined early on the first day of life and again at the end of the fourth d

An approach to the measurement of body fluid compartment volumes in non-steady conditions in the rat.

Abstract: A method has been developed by which body fluid volume changes can be assessed frequently after only one initial injection of the appropriate radioactive tracers. This method is based on the assumptions that, 1. following their intravenous injection, the temporal behaviour of tritiated water or radio-sodium can be adequately modelled by the kinetic behaviour of an open, interconnected two-compartment system; 2. known amounts of tracer are added to or irreversibly removed from the system only via the first compartment. In the measurement of body fluid volume changes in rats after isotonic blood volume expansion, the rapid urinary tracer excretion was treated as a series of negative tracer "injections" made instantaneously into the first tracer compartment at the mid point of each short urine collection period. The effect of these "injections" on the first compartment was regarded as diminishing with time in accordance with the steady state rate constants. The vaolues for non steady state changes in total body water volume and functional extracellular fluid volume obtained by such a mathematical treatment, agreed closely with directly measured changes where such direct comparisons could be made.

Distribution and Dynamics of Body Fluids in Sheep

Abstract: The evolution of metazoa centres around the separation of potassiumrich cell fluid from the sodium-based extracellular transport medium: the blood. More than half the energy of liver cells is used in removing sodium from the cell matrix by membrane-based active transport (50). On the surfaces of the body the absorption of sodium and prevention of its loss, is an expensive process of active transport carried out by the gut and its glands, by sweat glands or renal tubules, for the maintenance of extracellular fluid concentration and volume, as part of the total flux of energy and water.

Growth of the pig: changes in body weight and body fluid compartments.

Abstract: Body weight and the rate of change in TBW, ECW, and ICW were measured in 252 anesthetized pigs during the first 12 weeks after birth. After TBW was measured with 3H2O, 55 of the pigs were killed and TBW measured by desiccation. 3H2O overestimated TBW by 6.5% of body weight and 4.9% of fat-free wet weight, compared to desiccation (P less than 0.001); mean figures for 3H2O were 78.6 +/- 1.02% of body weight, and for desiccation, 72.1 +/- 0.45%; on a FFWW basis, 88.6 +/- 0.94% for 3H2O, and 83.7 +/- 0.13% for desiccation. TBW decreased significantly from 85.0% of body weight at birth (1.5 dg) to 75% at 5 kg (day 28) at a rate of ---3.2% body wt/kg body wt (P less than 0.001 from a zero rate). After that the rate of decrease was not different from zero: --0.117% body wt/kg body wt. ECW decreased significantly from 48% at birth to 35% at day 28 at a rate of --3.802% body wt/kg body wt (P less than 0.001 from a zero rate), and after day 28 the rate of decrease was not different from zero (--0.149% body wt/kg body wt) through week 12. ICW decreased, but not significantly, at a rate of --0.099% body wt/kg body wt. The changes in the rate of decrease in TBW and ECW coincided with weaning, and it was speculated that there was a direct relationship between the two events.

Body composition of mice following exposure to 4300 and 6100 meters.

Abstract: Male Swiss mice were exposed for 3 and 7 d to simulated altitudes of 4300 and 6100 m. Body weight losses were enhanced at the higher elevation and after longer exposure at each elevation. Carcass analyses showed the weight losses to be attributable to decrements in body water and fat content. The water decrements were a little greater than the fat decrements after all exposure conditions. At both elevations, however, fat loss increased significantly as exposure was extended from 3 to 7 d whereas water loss remained unchanged.

Distribution of sodium and potassium in chronic obstructive pulmonary disease.

Abstract: The body electrolyte composition of 34 patients with severe chronic obstructive pulmonary disease and without complications or medications known to influence body sodium or potassium was studied. Exchangeable sodium, exchangeable potassium, extracellular water, and total body water were measured using radioisotope dilution techniques. From these values and serum sodium and potassium levels, the intracellular water, intracellular concentrations of sodium and potassium, and factors to estimate lean body mass were calculated. Normal values were predicted for factors that vary with weight, age, and sex--exchangeable sodium, exchangeable potassium, total body water, extracellular water, intracellular water, and estimates of lean body mass--for each subject using regression equations that took into account the variables. For values that do not vary with weight or age--residual sodium and intracellular concentration of potassium--comparisons were made with values from our control subjects. The patients with chronic obstructive pulmonary disease showed a slower rate of potassium exchange than the control subjects, requiring at least 48 hours. There was also an increase in residual sodium composed of intracellular sodium and exchangeable bone sodium. The possibilities that the abnormalities could be ascribed to congestive heart failure, loss of lean tissue, or to a slowly functioning sodium pump were considered.

Effective body water half-life and total body water in rhesus and cynomolgus monkeys.

Abstract: Although body water content and effective water half-life have been determined in several mammalian species, including man, these measurements are not available for sub-human primates to our knowledge. Values were therefore determined in a group of rhesus and cynomolgus monkeys. A fairly wide range of water half-life values was found in each of the two species between animals, but there was little variation within animals who had more than one determination over the course of 1 year. Mean values for effective water half-life were 7.2 days and 3.7 days for naturally menstruating females of the cynomolgus and rhesus species, respectively. Water half-life in female rhesus monkeys with artificial menstrual cycles averaged 6.2 days. Females of both species had a similar percentage of body water content of 64%. Water half-life measured 7.1 and 8.5 days in two male rhesus; and water content was 62% of body weight in one of these animals.

Body Fluid Distribution in Acute Hypercapnia

Abstract: : Guinea pigs and rats were exposed to 1.9, 6.9 and 10.8% CO2 for a period of one hour. Measurements of total body water (TBW), extracellular fluid (ECF) and intracellular fluid (ICF) were made using tritiated water and radioactive chloride (Cl36). Control values for TBW, ECF and ICF were 64.6, 28.5 and 36.1 for rats and 61.7, 30.6 and 31.1 for guinea pigs. These values did not change significantly under hypercapin. These results indicate that although no measurable changes occurred in body fluid distribution under hypercapnia, the differences in body water distribution between guinea pigs and rats may help explain species differences in response to hypercapnic stress.