Showing papers on "Body water published in 1985"

Quetelet's index (W/H2) as a measure of fatness

Abstract: A weight-height index of adiposity should indicate the relative fatness of subjects of differing height unless obesity is itself correlated with height. The average body fat among adult women attending a hospital outpatient clinic for obesity was 40.5 percent of body weight. The height of an unselected series of 286 of these outpatients was found to be similar to that of the general population of women of similar age, which indicates that obesity in adult women is not significantly related to height. Body composition was measured by body density, body water and body potassium in a series of 104 female and 24 male subjects aged 14-60 years. In both sexes density, water and potassium gave progressively higher estimates of body fat (kg), and there was a significant difference between the values by different methods. The average of the estimates by these three methods was taken to be the 'true' value for each individual (F kg). Regression of F/H2 on W/H2 (Quetelet's index) gave a correlation coefficient of 0.955 for women and 0.943 for men. The deviation of the body fat estimated from Quetelet's formula from the 'true' value was not much greater than that when density, water or potassium were used as a basis for estimating body fat. It is concluded that Quetelet's formula is both a convenient and reliable indicator of obesity.

Fatness, Menarche, and Female Fertility

Abstract: It is hypothesized that a particular ratio of fat to lean mass is required for menarche and the maintenance of regular menstrual cycles. Females who lose 10-15% of normal weight for height equivalent to a loss of 1/3 of body fat become amenorrheic presumably due to hypothalamic dysfunction. Adipose tissue may provide signals to the central nervous system and gonadotropin regulatory areas either directly by estrogen production or indirectly by the effects of relative fatness on temperature control and metabolic rate or by both means. Women with hypothalamic dysfunction experience changes in the secretion of gonadotropins luteinizing hormone follicle-stimulating hormone and estrogen. Weight gain restores postmenarcheal secretion patterns. This approach suggests that the secular trend toward earlier age at menarche reflects earlier attainment of critical weight as a result of improved nutrition and child care. In many societies subnutrition may explain the observed submaximum fertility. This suggests a need to integrate family planning programs with nutrition programs in many developing countries. It is important to note that the prediction of the minimum weight for height for onset and maintenance of ovulatory cycles is from total water as percentage of body weight. Although the percentage of fat in the body is inversely related to the percent of body water only the latter is predictive. Successful prediction of the minimum weights for height is related to a lean mass/fat ratio represented by about 17% fat of body weight at menarche and 22% of body weight at the completion of growth at age 18 years.

The relative contribution of body fat and fat pattern to blood pressure level.

Abstract: Although the association between body weight and blood pressure is irrefutable, body fat mass and blood pressure level may not necessarily be directly related. To clarify the relative contribution of fat mass to blood pressure level, we analyzed data on 399 adults consecutively entering a weight control program. Although most subjects were notably overweight (mean ideal body weight 177%), the population represented a wide spectrum of body weights and blood pressure levels. Study parameters included body fat mass (by total body water, 40K, and Steinkamp formula), lean body mass, body build (chest to height ratio), fat cell number and size from bilateral buttock biopsy specimens, upper fat pattern by arm to thigh circumference ratio, and central fat pattern by subscapular to triceps skinfold ratio. Our results concurred with previously noted correlations between obesity and blood pressure (as mean arterial pressure): weight (r = 0.44), percentage of body fat (r = 0.19), and absolute fat mass (r = 0.38; all p less than 0.01); however, lean body mass, age, and body build correlated highly with both fat mass and mean arterial pressure, thereby confounding this relationship. Multivariate analysis was performed to evaluate the relative contribution of fat mass to mean arterial pressure in the presence of these and other potentially confounding variables. Lean body mass, age, body build, and an upper body fat pattern were found to contribute significantly to the variation in mean arterial pressure (p less than 0.01). In their presence, percentage of body fat, absolute fat mass, central fat pattern, fat cell characteristics, and age of onset of obesity did not significantly improve the predictability of mean arterial pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute alcohol intoxication and body composition in women and men.

Abstract: The present study was a direct experimental comparison of administering equivalent alcohol doses based on body weight and estimated total body water to 12 women and 12 men. Each subject participated in two experimental sessions separated by at least three days. Two doses of 95% ethanol were administered in a randomized, counterbalanced order: 0.66 ml/kg of body weight, and 1.2 ml/l of total body water. Women were tested during the midfollicular phase of their menstrual cycle when plasma concentrations of estrogen and progesterone have been found to be lower than other phases of the cycle. When given doses equated for body weight, women reached significantly higher peak blood alcohol concentrations than men. No sex differences were found when equivalent doses based on total body water were administered. This differential effect of dose determination was not reflected in self-reported levels of alcohol intoxication. The anthropometric equations used to estimate total body water provided a practical, reliable method for equating alcohol doses.

Body composition in elderly people. I. Determination of body composition by multiisotope method and the elimination kinetics of these isotopes in healthy elderly subjects.

Abstract: The body composition of 40 healthy elderly and 20 healthy young subjects was determined and compared. It was found that the age-related changes were more marked in females than in males. Total body water was decreased as a consequence of diminished lean body mass. Extracellular fluid volume remained unchanged, while plasma volume increased. Thus, the liquid components of lean body mass were redistributed between the intracellular and extracellular spaces. The elimination kinetics of isotopes were not significantly different between young and aged subjects, except the elimination of radiosulfate.

Age-related differences in blood ethanol parameters and subjective feelings of intoxication in healthy men

Abstract: Healthy men within 4 age groups, 20–29, 30–39, 40–49 and 50–59 years ( N = 12 per group), drank 0.68 g/kg ethanol as neat whisky after fasting overnight. The drink was finished within 20 min and the concentrations of ethanol in capillary blood were determined at 30/60 min intervals for 7 hr. At the time of blood sampling, the men were asked to estimate their feelings of intoxication according to an arbitrary scale on which the score 10 indicated ‘tipsy’ or a ‘Little high’. The time course of blood ethanol concentration was similar in all 4 groups with the curve for 50–59-year-old men on the highest level and 20–29-year-old men lowest. Subjective intoxication scores were significantly less in the youngest age group and the maximum score for each subject was correlated with age ( r = 0.45, P ≪ 0.01). Total body water (TBW) was not correlated with age directly ( r = 0.17, P > 0.05) but when it was expressed as percent of body weight a strong negative correlation was found ( r = −0.77, P > 0.001). The mean total body water estimated from ethanol dilution was 46.7 ± 4.11. (+ SD, N = 48) and this corresponds to 58% of mean body weight of the men. The distribution volume of ethanol/kg body weight ( V d) decreased with ageing ( r = −0.59, P < 0.001) being 0.72, 0.71, 0.68 and 0.66 l/kg on average in the 20–29, 30–39, 40–49 and 50–59-year-old age groups respectively. The reduction of V d corresponds to an age-related decrease in the percentage of body water and an increase in the percentage of body fat. This results in elevated blood ethanol concentrations in older individuals for a constant dose/kg body weight. The absorption of ethanol from the gut and its rate of disappearance from blood were not markedly influenced by age. The lower subjective feelings of intoxication reported by younger men may indicate that age-related differences in acute functional tolerance to ethanol or different threshold values of blood ethanol may exist before an effect is felt.

Estimation of plasma volume changes during marathon running.

Abstract: Indices of fluid loss have been compared in 47 male runners who completed a competitive marathon (422 km) race in times varying from 2 hr 37 min to 4 hr 51 min Body weight was recorded before and after the race; venous blood samples were collected shortly before and immediately after the race and used for the estimation of haemoglobin concentration, packed cell volume and serum concentration of albumin and total protein All runners drank a total of 14 L of water during the race The mean decrease in body weight was 21 +/- 08 kg (mean +/- SD), corresponding to 30 +/- 11% of initial weight The decrease in plasma volume (PV), calculated from the haematological parameters, was 65 +/- 78% (P less than 0001) Serum total protein concentration increased (P less than 0001) by 104 +/- 48% and serum albumin (P less than 0001) by 96 +/- 56% The increase in serum protein concentration was correlated (r = 064, P less than 0001) with the calculated decrease in PV, but was greater (P less than 0001) than could be accounted for by the loss of plasma water The change in PV varied widely between individuals and was unrelated to running speed The estimated decrease in total body water (5%) was not different from the decrease in PV (65%), suggesting that water losses were evenly distributed between the intracellular and extracellular compartments

Measurement of net transplacental transfer of fluid to the fetal sheep.

Abstract: If fetal drinking activity is prevented and it is assumed that in the latter third of gestation the fetus is capable of maintaining itself in fluid balance, then the net amount of fluid gained across the placenta by the fetus is equal to the amount of fluid lost from the fetus, by routes other than the placenta, plus fluid deposited in growing tissues minus the amount of water produced as a result of oxidative metabolism. Net transplacental transfer of fluid to the fetus over a 3 h period was measured in eight chronically catheterized fetal sheep in which drinking activity was prevented by ligating the oesophagus. Urine and lung liquid flow rates were measured. In the latter third of gestation, these are the only significant sources of fluid loss from these fetuses during the 3 h experimental period. Water produced as a result of oxidative metabolism was calculated, as was the amount of fluid deposited in growing tissues during the course of the experiment. The weight of the fetus at the beginning of the experiment and the change in weight that occurred during the experiment was calculated by measuring the weight of the fetus at death (within 30 h) and applying an equation which describes the body weight-gestation age relationship for merino sheep. Net transplacental fluid transfer was 0.40 +/- 0.09 ml min-1 kg-1 (range 0.30-0.54 ml min-1 kg-1). Fetal urine flow rate averaged 0.30 +/- 0.11 ml min-1 kg-1. It was 72.8 +/- 10.0% of the volumes used to calculate net transplacental fluid transfer to the fetus. Lung liquid flow rate was 0.079 +/- 0.039 ml min-1 kg-1. It was 20.2 +/- 9.2% of the volumes used to calculate net fluid intake. The amount of fluid deposited as a result of tissue growth was 0.023 +/- 0.001 ml min-1 kg-1; it was 5.94 +/- 1.1% of the volumes used in the equation, while the production of water as a result of metabolism was 3.9 X 10(-3) ml min-1 kg-1 (Conrad & Faber, 1977) and constituted 1.01 +/- 0.22% of the volumes used in the equation. This method of measuring net transplacental fluid transfer to the fetus can be used to measure fetal fluid intake over relatively short periods of time. It also means that the effects of disturbances in maternal fluid and electrolyte balance on fluid transfer to the fetus can be studied and quantitated.

Mofification of body composition by clenbuterol in normal and dystrophic (mdx) mice

Abstract: Female dystrophic mice (mdx on C57 Black background) gained weight more rapidly than age-matched controls and had a higher body fat content (% body weight), a slightly lower protein content and a reduced mass of muscle. Chronic treatment (21 d) of the mice with theβ2-agonist clenbuterol stimulated weight gain in both genotypes without affecting energy intake. Clenbuterol increased the mass of the gastrocnemius and soleus muscle by 13% and 29% in normal and dystrophic mice, respectively, and raised body protein but depressed body fat. Body water and energy content were unaffected by clenbuterol, but the ratio of protein to fat in the carcasses was enhanced by 17% in normal and 56% in dystrophic mice following clenbuterol treatment. Thus, theβ2-agonist restored the body composition of dystrophic mice to normal and enhanced the protein to fat ratio in both these and normal mice.

Composition of postnatal weight-loss and subsequent weight-gain in small for dates newborn-infants

Abstract: Using a sucrose and deuterium oxide dilution technique body water compartments and solids were serially determined in small for dates newborn infants at birth, at the moment of maximum postnatal weight loss and on recovery of birth weight. Compositions of weight loss and subsequent weight gain were calculated from the differences in body water compartments and solids between the first and the second and the second and the third study, respectively. Birth weight of the infants was 1.55 +/- 0.46 kg (mean +/- SD) (N = 7), gestational age was 35.7 +/- 3.1 weeks. Results show that despite changes in extra- and intracellular water volumes during weight loss, total body water volume and solids per unit of body weight remained remarkably constant throughout the study. Compositions of weight loss and subsequent weight gain were similar to body composition. This suggests that in small for dates newborn infants postnatal weight loss is the result of catabolism rather than dehydration and subsequent weight gain is the result of growth rather than rehydration.

Measurement of body fat and hydration of the fat-free body in health and disease

Abstract: Body fat mass, fat-free body mass and body water are basic components of body composition which are used in nutritional and metabolic studies and in patient care. A method of measuring total body fat (TBF), fat-free mass (FFM) and its hydration (TBW/FFM) involving prompt gamma in vivo neutron activation analysis (IVNAA) and tritium dilution has been compared with the more traditional methods of densitometry and skinfold anthropometry in 36 normal volunteers, and with skinfold anthropometry in 56 patients presenting for nutritional support. While the mean values of TBF were in reasonable agreement for the three methods in normals it was founds that skinfold anthropometry underestimated TBF relative to the IVNAA/tritium method by, on average, 3.0 kg (19%) in patients. Furthermore, the ranges of values in normals of the ratio TBW/FFM for the anthropometric (0.62 to 0.80) and densitometric (0.65 to 0.80) methods were much wider than the range for the IVNAA/tritium method (0.69 to 0.76), in which TBW was measured by tritium dilution in all cases. In the patients, the ranges of this ratio were 0.52 to 0.90 for the anthropometric method and 0.67 to 0.82 for the IVNAA/tritium method; clearly anthropometry yields values of TBW/FFM which are outside accepted biological limits. On the basis of these findings, ranges of TBW/FFM are suggested for both normal adults (0.69 to 0.75) and patients requiring nutritional support (0.67 to 0.83). Finally it is concluded that the IVNAA/tritium method is a suitable method for measuring TBF and FFM and particularly so when body composition is abnormal.

Measurement of total body water in intensive care patients with fluid overload

Abstract: The measurement of total body water (TBW) in critically ill intensive care patients with greatly expanded TBW allows body composition studies to be undertaken in such patients with potentially important clinical consequences. Previous workers in this field have stressed the importance of the distortion of compartmental specific activity resulting from continued intravenous (IV) fluid administration during the period of equilibration and have made attempts to predict the equilibrium value of specific activity from the early arterial kinetics. In this paper a method for the measurement of TBW in critically ill intensive care patients is presented together with results of 16 studies on 11 such patients (mean TBW 54.61). It is shown that the effect of continued IV fluid administration in association with prolonged equilibration is small and that the prediction of TBW from analysis of the early (first hour) arterial kinetics is inappropriate. It is concluded that in such patients the volume of distribution of the isotope is constant after four hours from IV injection and that TBW can be measured with a mean precision of 0.7% (SD) from the fourth, fifth, and sixth hour measurements.

Can tritiated water-dilution space accurately predict total body water in chukar partridges?

Abstract: Total body water (TBW) volumes determined from the dilution space of injected tritiated water have consistently overestimated actual water volumes (determined by desiccation to constant mass) in reptiles and mammals, but results for birds are controversial. We investigated potential errors in both the dilution method and the desiccation method in an attempt to resolve this controversy. Tritiated water dilution yielded an accurate measurement of water mass in vitro. However, in vivo, this method yielded a 4.6% overestimate of the amount of water (3.1% of live body mass) in chukar partridges, apparently largely because of loss of tritium from body water to sites of dissociable hydrogens on body solids. An additional source of overestimation (approximately 2% of body mass) was loss of tritium to the solids in blood samples during distillation of blood to obtain pure water for tritium analysis. Measuring tritium activity in plasma samples avoided this problem but required measurement of, and correction for, the dry matter content in plasma. Desiccation to constant mass by lyophilization or oven-drying also overestimated the amount of water actually in the bodies of chukar partridges by 1.4% of body mass, because these values included water adsorbed onto the outside of feathers. When desiccating defeathered carcasses, oven-drying at 70 degrees C yielded TBW values identical to those obtained from lyophilization, but TBW was overestimated (0.5% of body mass) by drying at 100 degrees C due to loss of organic substances as well as water.

Hydration of fat-free body in protein-depleted patients.

Abstract: 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.

Body size, composition, and fitness in adolescents with elevated blood pressures.

Abstract: Increased body size is often found in children with elevated blood pressures, but it is not clear whether this is a result of obesity or early maturity. Similarly, levels of activity and fitness have marked effects on blood pressure and body composition. To study these interrelated factors, we measured height, weight, and body composition (skinfold thickness and total body water) as well as heart rate, blood pressure, and oxygen consumption at rest and during exercise in 192 ninth grade boys and girls, 102 with persistently elevated blood pressures at or above the 95th percentile and 90 matched controls with blood pressures below the 50th percentile for the entire population of 10,641 Dallas County ninth graders tested. Differences in resting blood pressures also were present during maximal exercise and recovery periods. Boys with persistently elevated blood pressures were characterized by increased supine and recovery heart rates, normal fitness, excess size for age in the absence of obesity, and early maturation. Girls with persistently elevated blood pressures had increased heart rates, decreased fitness, and obesity.

Creatinine excretion over 24 hours as a measure of body composition or of completeness of urine collection.

Abstract: Continuous collections of urine for up to 3 weeks from obese patients on a meat-free low-energy diet showed fluctuations in creatinine excretion so that the coefficient of variation was 8.7-34.4 per cent. Urine creatinine excretion was poorly correlated with measures of lean body mass such as density, body water or body potassium. Under the conditions of our study creatinine excretion is not a reliable indicator of either lean body mass nor the completeness of urine collection. We also conclude that the increased lean body mass in obese women contains a relatively small proportion of muscle.

Evaluation of the use of deuterium oxide dilution techniques for determination of body composition of beef steers.

Abstract: Body composition as estimated by a one- or two-compartment deuterium oxide dilution technique was compared with directly measured body composition of 15 large- and 15 small-frame steers. Body composition of the steers was measured at 219, 412 and 603 kg live weight. Empty body protein was overestimated (P less than .05) 3.6% from a one-compartment model (1 CM, using the slope, intercept method), while empty body protein was underestimated (P less than .05) 5.4% from a two-compartment kinetic model (2CM). Empty body ether extract estimated by 1 CM was not significantly different from the direct method, although 4.7% larger. Empty body ether extract was overestimated (P less than .001) 32.2% by the 2CM. Empty body water was accurately estimated from the 1CM when a 3.2% correction factor was used for the overestimation of total body water by the 1CM, but water in gastrointestinal tract contents was overestimated (P less than .001) 13.4% by the 1CM. Empty body water was underestimated (P less than .001) 7.8% by the 2CM, and water in gastrointestinal tract contents was overestimated (P less than .001) 41.8% by the 2CM due to its dependence on regression equations that differ between groups of cattle. The 2CM offered no advantage over the 1CM. A three-compartment model was not better than the 2CM in estimating body water compartments. Assuming the amount of empty body water associated with either empty body protein or ash to be constant seemed to be valid. Suggested values calculated from data presented in the literature for growing cattle with an empty body weight greater than 175 kg are .302 and .0668, respectively, for the ratios of protein and ash to water. The relationship between empty body fat and water was, percentage empty body fat = 94.27--(1.267)(percentage empty body water), which had a 1.25 residual standard deviation and a .98 coefficient of determination.

Total body potassium and water, and exchangeable sodium, in muscular dystrophy.

Abstract: 1. Total body potassium ( 40 K method) and total body water and exchangeable sodium (both by isotope dilution) were determined in 26 boys, aged 5-17 years, with muscular dystrophy. Total body potassium values were compared with measurements in a large series of normal boys on the basis of height. 2. Total body potassium was reduced even in the youngest patients and was only slightly higher in the older boys, despite their considerably greater height. Exchangeable sodium increased with increasing height in a way similar to that of normal boys. Total body water was also reduced but increased with growth, although to a lesser extent than expected for normal boys. The total body water measurements indicated that many of the affected boys were very obese, despite an apparently normal body weight. 3. An intravenous bolus of 22 Na distributed at a similar rate in boys with muscular dystrophy to that in normal males. 4. In relation to the predicted values, total body potassium and 24 h urinary creatinine excretion of the affected boys both declined at a rate of 4% per year.

Maintenance of blood volume in snakes: transcapillary shifts of extravascular fluids during acute hemorrhage.

Abstract: 1. Tracer dilution analysis (D2O,51Cr, and NaS14CN) was used to investigate the steadystate compartmentation of body fluids and the extent of fluid transfer from extravascular to vascular spaces during hemorrhage-induced hypovolemia in two species of snakes,Elaphe obsoleta andCrotalus viridis. 2. Fluid spaces of the two species are not significantly different (means, blood volume 6.1, 5.4; extracellular fluid 42.2, 41.9; total body water 77.2, 77.2% body mass, respectively), but values for extracellular fluid exceed those reported for other reptiles. 3. Both species of snake withstand graded hemorrhage where 4% of the initial blood volume is withdrawn every 10 min until the cumulative deficit is 32%. Some snakes are able to maintain their initial blood volume throughout hemorrhage, while others restore 90% of deficits within 2 h after hemorrhage ceases. Typically, 50–60% of the hemorrhaged deficit is transferred from the interstitium to the circulation throughout hemorrhage (Fig. 2). The source of fluid entering the vascular space is entirely extracellular during hemorrhage, but fluid from the intracellular space may enter the blood within 2 h after hemorrhage ceases. Snakes are able to maintain arterial pressure during these experiments (Fig. 3). 4. The ability of snakes to maintain hemodynamic stability despite substantial losses of blood can be explained in terms of a large interstitial fluid volume that may shift rapidly to the vascula space. Shifts in the opposite direction also occur in response to hemodynamic factors, implying a low resistance to fluid movement across the capillary wall.

Continuous infusion of aldosterone: Correlates of body weight gain

Abstract: Aldosterone stimulated body weight gain in adrenalectomized male rats across all but the highest of seven doses delivered by continuous infusion Gains were especially strong in the latter part of the 12-day infusion period peaking at values twice those of adrenalectomized rats given only glucocorticoid replacement or sham infusions The gains were not related to skeletal growth, and hematocrit and percent tissue water were only modestly and inversely related to weight gain (rs = -24) In contrast, epididymal fat pad mass correlated strongly (r = 72), indicating that the gains were partly or wholly attributal to adipose tissue hypertrophy

Relationship between Metabolic Rate and Body Size in Fetal Life

Abstract: To define the O2 consumption rate (VO2) versus body mass relation during fetal growth, we compared fetal sheep VO2 at mid and late gestation. VO2 per kg wet weight was 37% higher at mid gestation. However, VO2 per kg dry weight was 2.5 times higher, and associated with a high viscera/body weight ratio. Fetal VO2 tends to grow proportionally to body mass because marked decreases in the relative growth of visceral organs and in the VO2/dry weight ratio are accompanied by a decrease in body water.

Effect of endotoxin administration on body fluid compartments in the horse.

Abstract: Plasma volume, extracellular fluid volume (ECFV), and total body water (TBW) were measured before and after endotoxin (Escherichia coli) administration in 6 conscious adult horses. Evan's blue dye, sodium thiocyanate, and antipyrine were the test substances used to estimate plasma volume, ECFV, and TBW, respectively. Pharmacokinetic analysis of plasma concentration vs time was used to determine changes in body fluid compartments. The pathophysiologic effects of endotoxin were monitored by clinical evaluation, blood chemical changes, and blood gas determinations. All horses became dyspneic within 15 minutes of endotoxin administration and clinical signs of colic were evident 30 to 45 minutes after endotoxin administration. After endotoxin administration, serum glucose and creatinine concentrations were significantly (P less than 0.05) elevated, and all horses became hypoxic and developed marked metabolic acidosis, and plasma volume decreased approximately 15% (P less than 0.05). A significant change in ECFV or TBW during the 300-minute experimental period was not observed.

Effects of flunixin meglumine on blood pressure and fluid compartment volume changes in ponies given endotoxin.

Abstract: A study was conducted to determine whether body fluids undergo a net shift from one compartment to another during endotoxin-induced shock in the pony, and whether flunixin meglumine alters these endotoxin-induced changes in the volumes of body fluid compartments. Total blood, RBC, and plasma volumes were determined, using 51Cr-labeled RBC and PCV that were corrected for trapped plasma. Total body water was measured by distribution of 3HOH. Arterial blood pressure was measured directly, using a blood pressure transducer. Treatment (flunixin meglumine, 1.1 mg/kg of body weight) was given to 6 of the 12 ponies 1 minute before an IV injection of Escherichia coli endotoxin (100 micrograms/kg of body weight, LD100). The PCV and RBC volume increased in both groups; however, the hemoconcentration was less in flunixin meglumine-treated ponies. In nontreated ponies, total blood volume and plasma volume decreased significantly during the first hour after endotoxin administration. In treated ponies, total blood volume did not vary significantly, and plasma volume decreased only slightly. In both groups, the increase in PCV was apparently due to splenic contraction, which increased the number of circulating RBC. Hemoconcentration was further increased in nontreated ponies by the loss of plasma into the interstitial space. Flunixin meglumine reduced plasma loss, minimized hemoconcentration, and maintained normal blood volume. Total body water remained constant in treated and nontreated ponies.

Body composition and nutritional status in patients on continuous ambulatory peritoneal dialysis (CAPD).

Abstract: Total body water (TBW), extracellular water (ECW), exchangeable potassium pool (EKP), and alkali-soluble nitrogen in skeletal muscle tissue (N) were determined in 9 CAPD patients on treatment from 5 to 14 months (mean 8.6 months). The parameters were reevaluated in 6 of these patients 5 to 13 months later (mean 8.6 months). The mean value of TBW was normal and directly correlated to body weight (BW), but TBW was abnormally distributed between extracellular and intracellular space. ECW volume was significantly lower than the predicted value (12.1 +/- 1.4 versus 16.8 +/- 1.9 l) and out of proportion to TBW (34.8 +/- 3.9% versus 47.8 +/- 1.5%). The calculated intracellular water, therefore, appeared clearly hyperexpanded. The mean value of EKP was slightly reduced, but in three patients there was a 25% reduction. N content was low in 5 out of 9 patients. When the parameters were re-evaluated BW and TBW were unchanged in two subjects. A third patient showed a simultaneous increase in both BW (12.7%) and TBW (19%). TBW variations (+19%, -23%, -24%) without changes in BW were seen in three patients. The mean value of EKP was unchanged, but there was a 25% reduction in one patient. N content improved in two and worsened in one of the three patients in whom it was determined. The data suggest that cell overhydration was the distinctive feature in our CAPD patients, and that the evolution of the nutritional status was variable, since the patients could remain stable, gain or loose body fat, and probably change their lean body mass.