Body Water Distribution Research Articles

Pharmacokinetics of Antimicrobials in Obese Children.

Childhood obesity is common and results in substantial morbidity. The most commonly prescribed drugs in obese children are antibiotics. However, physiologic changes associated with childhood obesity can alter antibiotic pharmacokinetics and optimal body size measures to guide dosing in his population are ill defined. This combination can result in therapeutic failures or drug-related toxicities. This review summarizes pharmacokinetic information for antibiotics in obese children and implications for dosing. We conducted a comprehensive literature search of PubMed, EMBASE, and International Pharmaceutical Abstracts to identify pharmacokinetic studies of antimicrobial agents in obese children. We included the following search terms: obesity, pharmacokinetics, pharmacodynamics, drug toxicity, dosing, anti-infective agents, antiviral agents, and antifungal agents. We identified four pharmacokinetic studies of antibiotics in obese children: one for cefazolin and tobramycin, one for gentamicin, and two for vancomycin. Only the cefazolin/tobramycin trial was prospective. The drugs studied differ in their tissue and body water distribution characteristics. Two of the studies (tobramycin and gentamicin) reported pharmacokinetic differences and required dosing modifications in obese children. The lack of pharmacokinetic studies in obese children is pronounced. The scarcity of pharmacokinetic data limits the ability to predict drug disposition using drug physicochemical properties and impedes a rational approach to selection of appropriate body size measures for dosing. Given this knowledge gap, additional trials in obese children are urgently needed and is a public health concern. Pharmacokinetic studies of antimicrobials in obese children are desperately needed to guide dosing and avoid therapeutic failures or unwanted toxicities.

PP065. Assessment of total vascular resistance and total body water in normotensive women during the first trimester of pregnancy in order to predict hypertensive complications

In pregnancy there is an increase in maternal cardiac output (CO) and a reduction in total vascular resistance (TVR). Abnormalities of this adaptive mechanisms lead to numerous disorders of pregnancy. Moreover the mother's body water composition undergoes important modifications in total body water (TBW), extracellular and intracellular body water (EBW, IBW). Aim of the study is to identify a group of patients at high risk of developing hypertensive complications of pregnancy in frist trimester. To investigate hemodynamic changes and distribution of body water during the frist trimester of pregnancy, we conducted an observational study. We evaluated CO, TVR and Time Flow Corrected (TFc) with the USCOM system, a non invasive method. Patients were, also, subjected to BIA (Body Impedance Assessment). We enrolled 120 healthy pregnant women. 20 patients, were excluded for bad signal. Absolute values of haemodynamic and body impedance measures are shown in Fig. 1. Patients were divided in two groups:Group A with TVR>1200 dyne and Group B with TVR<1200 dyne. CO values were higher in group B. There wasn't significant differences in TBW, haematocrit, TFc and WBI (water balance index: TBW/Hct) between the two groups. Our results show that at costant values of TBW, Hct and WBI,we can find difference in term of TVR and CO in the first trimester of pregnancy. These parameters may improve the accuracy of screening in clinical practice.

Intraoperative Fluids

There is increasing evidence that intraoperative fluid therapy decisions may influence postoperative outcomes. In the past, patients undergoing major surgery were often administered large volumes of crystalloid, based on a presumption of preoperative dehydration and nebulous intraoperative 'third space' fluid loss. However, positive perioperative fluid balance, with postoperative fluid-based weight gain, is associated with increased major morbidity. The concept of 'third space' fluid loss has been emphatically refuted, and preoperative dehydration has been almost eliminated by reduced fasting times and use of oral fluids up to 2 h before operation. A 'restrictive' intraoperative fluid regimen, avoiding hypovolaemia but limiting infusion to the minimum necessary, initially reduced major complications after complex surgery, but inconsistencies in defining restrictive vs liberal fluid regimens, the type of fluid infused, and in definitions of adverse outcomes have produced conflicting results in clinical trials. The advent of individualized goal-directed fluid therapy, facilitated by minimally invasive, flow-based cardiovascular monitoring, for example, oesophageal Doppler monitoring, has improved outcomes in colorectal surgery in particular, and this monitor has been approved by clinical guidance authorities. In the contrasting clinical context of relatively low-risk patients undergoing ambulatory surgery, high-volume crystalloid infusion (20-30 ml kg(-1)) reduces postoperative nausea and vomiting, dizziness, and pain. This review revises relevant physiology of body water distribution and capillary-tissue flow dynamics, outlines the rationale behind the fluid regimens mentioned above, and summarizes the current clinical evidence base for them, particularly the increasing use of individualized goal-directed fluid therapy facilitated by oesophageal Doppler monitoring.

Ontogeny and drug metabolism in newborns

In pediatric age and particularly in newborn infants the drug efficacy and safety are influenced by the growth and development on drug Absorption, Distribution, Metabolism and Excretion (ADME). Thanks to the fast development of pharmacogenomics and pharmacogenetics, the drug therapy promises to be adapted to the genetic profile of the individual, reducing considerably the side effects of drugs and increasing their efficacy. Interindividual variability in drug response is well known in both adults and children. Such a variability is multifactorial considering both intrinsic and extrinsic factors. Drug distribution in the neonate is influenced by a variety of age-dependent factors as a total body water content and distribution variations, role of drug transporters, blood/tissue protein binding, blood and tissue pH and perfusion. The development of enzymes involved in human metabolism were classified in 3 categories: 1) those expressed during the whole or part of the fetal period, but silenced or expressed at low levels within 1–2 years after birth; 2) those expressed at relatively constant levels throughout fetal development, but increased to some extent postnatally; and 3) those whose onset of expression can occur in the third trimester, but substantial increase is noted in the first 1–2 years after birth. Besides this intrinsic aspects influencing pharmacokinetics during the neonatal period there are other important events such as inborn or acquired diseases, environment and finally pharmacogenetics and pharmacogenomics. Thousands of deaths every years are caused by fatal drug reactions; among the potential causes there are not only the severity of the disease being treated, drug interactions, nutritional status, renal and liver functions, but also the inherited differences in drug metabolism and genetic polymorphism. Adverse drug reactions (ADRs) among pediatric patients have been shown to be three times more frequent than in adults. On August 2010 The National Institute of Child Health and Human Development (NICHD) addressed patient safety issues in the NICU, recognizing that to understand and prevent adverse events, systematic research and education in safety issues needed. From all these concepts in terms of ADME, pharmacogenetics (relative to a single gene) and pharmacogenomics (relative to many genes) it is becoming more evident the perspective of the new concept of individualized medicine. The goal of this should be to identify which group of patients responds positively, which patients are nonresponders and who experiences adverse reaction for the same drug and dose. The interindividual variability in response to any drug is mostly dependent on DNA sequence variations across the human genome, the haplotype map (HAPMAP). At present there is still a big distance beween the knowledge in genetic and the practical application to model the drug profile to the genetic/genomic profile of the single patient. In the neonatal period the effects of growth in the pharmacodynamic, processes can help optimizing the dosage of neonatal frequently used medicines, thereby, minimizing their toxicity and increasing their efficacy. It should be useful to create accurate dosage adjustments according to the week of development.

PP114-MON HIGH PROPORTION OF DIETARY FAT INTAKE INCREASES RISK OF BEING MALNOURISHED 10 YEARS LATER

Rationale: Position of the body and consequent distribution of body water between body compartments affect the accuraccy of bioelectrical impedance analysis (BIA) and may lead to incorrect information about an individual’s body composition. This study aimed to compare the accuracy of body fat estimates obtained with standing leg-to-leg (LL) and supine hand-to-leg (HL) BIA techniques relative to anthropometry, and to evaluate the effects of body position on BIA-determined body fat percentage (BFP). Methods: The BFP of young males and females (n = 40) was determined with LL (adjusted for standing position) and HL (adjusted for supine position) BIA analysers, as well as from gender-specific Durnin and Womersly anthropometric equations used as the reference method for BIA body fat estimation. Each subject was measured with LL analyser in a standing position, before and after 20 minutes of supine rest, and with HL analyser in a standing and a supine position, before and after 20 minutes of supine rest. All measurements were taken under constant and controlled conditions. Significance of differences was assessed by means of one-way ANOVA for repeated measures. Results: The results demonstrate that the BFP as determined with different BIA analysers in different body positions differ significantly according to the procedure used (P< 0.01). In general, BIA values of BFP obtained after 20 minutes of supine rest tend to overestimate, and values obtained in upright position underestimate the actual BFP. Conclusion: The results of this study demonstrate that BIA estimations of BFP depend on the position of the body during the measurement, likely due to the posturerelated distribution of water in the body. Consequently, the use of different metods can classify one subject into different body fat content categories, which calls for further standardisation. Disclosure of Interest: None Declared.

SPANISH MULTICENTRIC STUDY ABOUT NUTRITION-INFLAMATIONhn WITH MID DILUTION (ENIMID STUDY): PRELIMINARY RESULTS

Introduction and aims The prevalence of malnutrition are 23-76% of ESRD patients undergoing HD, and 20-50% of them suffers inflammation. Nowadays, the “malnutrition-inflammation” duo is frequently found in HD patients.The aim of this Spanish multicenter study is to evaluate the effects of the Mid-Dilution HDF on the inflammatory-nutritional state, on some body composition and on the quality of life in the HD patients. The total number of patients expected 64; the preliminary analysis of 52 patient/3 months and 23 after 6months (the study will last 1 year), is presented. Methods Patients undergoing standard HD treatment with High Flux dialyzers for 4 hours/three times a week passed to HDF Online MidDilution with OLPUR 220 filters at a reinfusion rate of 12l/h.The patients are classified by: age, gender, Charlson comorbidity index, dialysis vintage. The parameters analyzed each 3 months are: urea, β2microglobuline, albumin, pre-albumin, CRP, fibrinogen, IL6, IL10, leptin, adiponectin, neuropeptide Y, body composition by BIVA parameters and apetite and quality life surveys. RESULTS Patients classification: • Age: 64.06±0.8 years; • Sex: 64% male; • Charlson-index: 3.97±1.66; • HD vintage 54.7±44.8 months.Significant decrease of β2microglobuline pre-dialysis from baseline 26,16 to 20,06 mg/L ( p = 0,006) after 3 months and to 17,88smg/L ( p = 0.09) after 6 months. x β 2microglobulineRR was 82.45 ±3.20 % and the URR was 79.56±3.51 %, which demonstrates a good removal of medium and small molecules. The Kt/V remained stable (>1,5). Albumin increased from 3.81 g/dL to 3.87 g/dL in e months and to 3.89 g/dL in the 6 months of evaluation. No significant differences in levels of pre-albumin (xbaseline 28 mg/dl). Corporal and BIVA parameters evolution These data shown an improvement of the body composition and water distribution. .Sig. improvements were seen in the appetite scale in the first 6 months ( p = 0.09). The total Quality of Life, evaluated in 3 months by SF36, increased from 55,61 to 50,66 ( p = 0,05); the physic from 50,28 to 55,92 ( p = 0,036); the mental from 55,69 to 60,1 ( p = 0,12).Cytokines:we found an increase in neuropeptide Y and IL10 and no significant changes in leptin and adiponectin with slight increase of IL6. CONCLUSIONS 1-The preliminary results show that MidDilution provides a good removal of small and middle molecules, increases appetite by providing a proper balance of cytokines through stimulation of antiinflamatory ones and neuropeptide Y. 2-It provides an improvement of body composition. Finally MidDilution improves nutritional parameters which leads to a better quality of life, as well as physical and mental status.

Water requirements and body water distribution in Awassi sheep and Aardi goats during winter and summer seasons

SUMMARYWater requirements, total body water (TBW) and water distribution were evaluated in Awassi sheep and Aardi goats of Saudi Arabia. Ten non-pregnant and non-lactating females from each species were individually housed in shaded pens during winter and summer seasons. Each experimental period lasted for 2 weeks; the first week was an adaptation period, followed by an evaluation period of 1 week. Feed and water intake together with body weight were recorded daily. Five animals from each group were used for determination of body water, extracellular fluid (ECF) and plasma volume (PV) using dilution techniques. Urea and sodium thiocyanate were used for the estimation of body water and ECF, respectively, and Evans blue for PV determination. Intracellular fluid (ICF) and blood volume (BV) were calculated. Feed intake was not affected by either season or species. During the winter season, Aardi goats had lower water intake in comparison with Awassi sheep, but water intake increased in all animals during summer. TBW increased during summer in all animals, but with higher values in the Aardi goats. During summer, ECF tended to increase in Aardi goats. PV, expressed as a proportion of body weight, was not affected by season, but it was maintained at higher levels in the Aardi goats irrespective of season. It could be concluded that Aardi goats used water more economically when the ambient temperature was lower but, during the summer when ambient temperatures were higher, they increased their water intake and BW content to a greater extent and stored more water in the ECF compartment compared to Awassi sheep.

Bestimmung der komplexen elektrischen Leitfähigkeit biologischen Gewebes mittels kontaktloser Magnetimpedanzmessung / Estimation of biological tissue conductivity with contact-free magnetic impedance measurements

At present, there are several methods that utilize electrical conductivity of biological tissue, such as biological impedance spectroscopy (BIS). Because these techniques use conductivity values for further analysis (e.g., body water distribution, etc.), accuracy of conductivity measurement is crucial. Traditionally, most impedance-based techniques rely on conductive interaction between tissue and external electrical measurement devices. Thus, electrode properties can influence the results of conductivity measurements. In this study, a contact-free measurement technique is presented, which is based on magnetic induction of eddy currents and measurement of the tiny reinduced voltages in external measurement coils. Our results indicate that it is principally possible to determine conductivity of biological tissue with this technique.

Hereditability Defect in Red‐Cell K in Hypertension

Background:Following our description of an hereditability of a decreased erythrocyte K [K]er independent of cell Na, in essential hypertension (EH), a long‐term study of RBC (Ki, Nai, H2O) content, plasma (Na, K, Cl, ionized Ca++), trans‐tubular K gradient (TTKG), total body K (TBK) and body water distribution by Bio‐Impedance Analysis was carried out in 185 hypertensives (47±19 y, 57 females; BP 167±11/101±7 mm Hg).Results:All cases had low Ki (85.3±6 mmol/l vs 96.2±4 mmol/l in normal, p&lt;0.001) despite normal (82%) or mild elevated Nai (7.2±1.3 mmol/l vs 6.2±1.1 mmol/l in normal, p=NS), despite similar urinary Na excretion (107±22 vs 101±35 mmol/l). Patients with lowest Ki (78.3±5 mmol/l) had lower urinary K 21±15 mmol/l), TTKG (4.2±0.7) and higher 12‐h urinary volume (≥1.3 ml/min) than those with higher Ki (86.5±6mmol/l, p&lt;0.002), urinary K (39±11mmol/l, p 0.004), TTKG (7.2±1.3) but lower 12‐h urinary volume (≤0.85 ml/min). Reversal of this abnormal Ki content in hypertensives was associated with decline and better control of BP (82%), fasting plasma glucose and regression of ST‐T alterations related to LVH hypertrophy (71%) or coronary artery disease (61%). Such body K disturbances, recorded at different month periods, unrelated to age, sex, race or dietary K intake in the hypertensives, and present in half (48%) of their normotensive offspring were implying a defective K mechanism in erythrocyte‐progenitor cells.Conclusion:These observations strongly suggest a critical role of RBC in normal body K homeostasis that is disturbed in EH.

A Physiological Model to Evaluate Drug Kinetics in Patients with Hemorrhagic Shock Followed by Fluid Resuscitation

To build a physiologically based pharmacokinetic model describing drug kinetics in interstitial fluid in case of hemorrhagic shock, and to propose a simple method to determine the subset of influential parameters that may be estimated with the data at hand. The model, which accounts for alterations of regional blood flows and body water distribution, was fitted to amoxicillin and clavulanate kinetic data, assessed in 12 trauma patients with hemorrhagic shock by comparison with 12 healthy volunteers. The predictions were the free concentrations of amoxicillin and clavulanate in 14 organs. In all tissues of trauma patients, the rate of distribution was lower, but the steady-state level was higher than those in healthy participants. Blood volume was reduced by 25% and blood flow in organs other than lung, brain, and heart were reduced by 18%. Compared with healthy subjects, the time that free amoxicillin concentration remained above 8 mg/L in the interstitial fluid of trauma patients was higher in blood and muscles, and lower in the tendon compartment. The results and predictions were consistent with the knowledge in this field. The model may be useful to optimize clinical trial designs and drug dosing regimens.

WS1-4-3 Circadian Variation of Body Water Distribution in Patients with Nocturnal Polyuria : Assessment by Bioelectric Impedance Analysis (BIA)(Urodynamic, Prostate and Urethra)

WS1-4-3 Circadian Variation of Body Water Distribution in Patients with Nocturnal Polyuria : Assessment by Bioelectric Impedance Analysis (BIA)(Urodynamic, Prostate and Urethra)

Hipokalemia, hipovolemia y repercusión electrocardiográfica secundarias a ingesta prolongada de furosemida: Caso clínico

Hypokalemia (serum K+ < 3.5 mEq/1) is a potentially serious adverse effect of diuretic ingestion. We report a 27 year-old woman admitted with muscle weakness, a serum potassium of 2.0 mEq/1, metabolic alkalosis and EKG abnormalities simulating cardiac ischemia, that reverted with potassium chloride administration. She admitted high dose furosemide self-medication for edema. Glomerular filtration rate, tubular sodium reabsorption, potassium secretion, the renin-aldosterone system, total body water distribution and capillary permeability, were studied sequentially until 90 days after her admission. There was hyperactivity of the renin-aldosterone axis, reduction in extracellular and intracellular volumes, normal capillary permeability and high sodium tubular reabsorption, probably explained by a "rebound" salt retention associated with her decreased extracellular volume.

Errors in the estimation of hydration status from changes in body mass

Hydration status is not easily measured, but acute changes in hydration status are often estimated from body mass change. Changes in body mass are also often used as a proxy measure for sweat losses. There are, however, several sources of error that may give rise to misleading results, and our aim in this paper is to quantify these potential errors. Respiratory water losses can be substantial during hard work in dry environments. Mass loss also results from substrate oxidation, but this generates water of oxidation which is added to the body water pool, thus dissociating changes in body mass and hydration status: fat oxidation actually results in a net gain in body mass as the mass of carbon dioxide generated is less than the mass of oxygen consumed. Water stored with muscle glycogen is presumed to be made available as endogenous carbohydrate stores are oxidized. Fluid ingestion and sweat loss complicate the picture by altering body water distribution. Loss of hypotonic sweat results in increased osmolality of body fluids. Urine and faecal losses can be measured easily, but changes in the water content of the bladder and the gastrointestinal tract cannot. Body mass change is not always a reliable measure of changes in hydration status and substantial loss of mass may occur without an effective net negative fluid balance.

Relationships between Physical Fitness and Endothelial Vascular Control in Elderly Men and Women

This study investigates correlations between physical fitness and endothelial vascular control and its underlying mechanisms in older men and women. A total of 38 healthy older adults (18 men, age 72.2±3.2 yr; 18 women, age 73.5±2.8 yr) were studied. All subjects received a three-minute step test to determine their cardiopulmonary index (CPI). Both percentage of body fat and distribution of body water, including total body water, intracellular water (ICW), and intracellular water (ECW), were measured by bioelectrical impedance analysis. Hemodynamic characteristics in the arterial and venous vessel were analyzed by impedance plethysmography, whereas skin vascular endothelial function was measured using a laser Doppler perfusion with iontophoresis. Our results showed that 1) hyperemic arterial flow, acetylcholine (ACh)-induced cutaneous perfusion, and the ratio of ACh to sodium nitroprusside (SNP)-induced cutaneous perfusion was positively correlated with CPI in both older men and women; 2) a lower CPI was accompanied by a higher ECW/ICW ratio in older women (r= −0.580), while a higher CPI was associated with a lower body fat in older men (r= −0.496); and 3) the ratio of ACh to SNP-induced cutaneous perfusion was negatively correlated with the ECW/ICW ratio in the female subjects(r= −0.538) and the body fat in the male subjects (r= −0.445). We conclude that endothelial vascular function can influence cardiopulmonary fitness in the elderly. Moreover, the age-related declines of physical fitness and endothelium-dependent vasodilation may be associated with the sex-related changes in body water distribution and fat percentage.

Cyclosporine enhances salt sensitivity of body water composition as assessed by impedance among psoriatic patients with normal renal function

Objective Cyclosporine (CsA) therapy may be accompanied by a significant increase in blood pressure, either sodium (Na+) independent or Na+ dependent. The relationship between Na+ intake and body water distribution among patients treated with CsA has not been evaluated. We report the study, by bioelectrical impedance analysis (BIA), of water composition changes after dietary salt manipulations both before and during CsA treatment of psoriatic patients. Methods Ten normotensive psoriatic patients, ages 37 ± 12 years (range, 19 to 54), with normal renal function were included. Each patient was assessed by BIA in 2 phases, before (phase 1) and during (phase 2) CsA therapy (3 mg/kg/day). In both phases, each patient was assessed in basal conditions (basal1 and basal2), on day 7 of a low-sodium diet (LS1 and LS2; 20 mEq/day) and on day 7 of a high-sodium diet (HS1 and HS2; 350 mEq/day). Plasma creatinine (Pcr), urinary volume excretion (Uv), urinary sodium (UNa+), urinary potassium (UK+), urinary osmolality (UOsmo), weight (Wt), resistance (R), reactance (Xc), total body water (TBW), extracellular water (ECW), intracellular water (ICW), Na:K exchangeable (Nae:Ke), phase angle (PA), and body cell mass (BCM) were evaluated. Blood pressure was monitored during 24 hours on the last day of each diet. Paired Student’s t-test was used to analyze the different phases. Results Before CsA treatment, Wt, TBW and Nae:Ke were lower during LS1 than during basal1, whereas TBW was higher during HS1 than during LS1. During CsA, Wt, TBW, ECW, and Nae:Ke were lower during LS2 than during basal2, whereas ICW and PA were higher during LS2 than during basal2. HS2 showed higher TBW, ECW, and Nae:Ke and lower ICW, PA, and BCM than during LS2. Systolic blood pressure was higher during HS2 than during LS2 or HS1. In addition, diastolic blood pressure was higher during HS2 than during HS1. Conclusion Body hydration status was more sensitive to dietary salt fluctuations during CsA treatment than without CsA, and a high-sodium diet seemed to enhance the CsA-induced hypertension side effect. Moreover, patients on low sodium intake under CsA treatment displayed neither any disturbance of body water composition nor any blood pressure change. Our data suggest that a low sodium intake might be very useful in preventing undesirable pressure and volume changes brought about by CsA treatment. Cyclosporine (CsA) therapy may be accompanied by a significant increase in blood pressure, either sodium (Na+) independent or Na+ dependent. The relationship between Na+ intake and body water distribution among patients treated with CsA has not been evaluated. We report the study, by bioelectrical impedance analysis (BIA), of water composition changes after dietary salt manipulations both before and during CsA treatment of psoriatic patients. Ten normotensive psoriatic patients, ages 37 ± 12 years (range, 19 to 54), with normal renal function were included. Each patient was assessed by BIA in 2 phases, before (phase 1) and during (phase 2) CsA therapy (3 mg/kg/day). In both phases, each patient was assessed in basal conditions (basal1 and basal2), on day 7 of a low-sodium diet (LS1 and LS2; 20 mEq/day) and on day 7 of a high-sodium diet (HS1 and HS2; 350 mEq/day). Plasma creatinine (Pcr), urinary volume excretion (Uv), urinary sodium (UNa+), urinary potassium (UK+), urinary osmolality (UOsmo), weight (Wt), resistance (R), reactance (Xc), total body water (TBW), extracellular water (ECW), intracellular water (ICW), Na:K exchangeable (Nae:Ke), phase angle (PA), and body cell mass (BCM) were evaluated. Blood pressure was monitored during 24 hours on the last day of each diet. Paired Student’s t-test was used to analyze the different phases. Before CsA treatment, Wt, TBW and Nae:Ke were lower during LS1 than during basal1, whereas TBW was higher during HS1 than during LS1. During CsA, Wt, TBW, ECW, and Nae:Ke were lower during LS2 than during basal2, whereas ICW and PA were higher during LS2 than during basal2. HS2 showed higher TBW, ECW, and Nae:Ke and lower ICW, PA, and BCM than during LS2. Systolic blood pressure was higher during HS2 than during LS2 or HS1. In addition, diastolic blood pressure was higher during HS2 than during HS1. Body hydration status was more sensitive to dietary salt fluctuations during CsA treatment than without CsA, and a high-sodium diet seemed to enhance the CsA-induced hypertension side effect. Moreover, patients on low sodium intake under CsA treatment displayed neither any disturbance of body water composition nor any blood pressure change. Our data suggest that a low sodium intake might be very useful in preventing undesirable pressure and volume changes brought about by CsA treatment.

Cyclosporine enhances salt sensitivity of body water composition as assessed by impedance among psoriatic patients with normal renal function

Cyclosporine (CsA) therapy may be accompanied by a significant increase in blood pressure, either sodium (Na+) independent or Na+ dependent. The relationship between Na+ intake and body water distribution among patients treated with CsA has not been evaluated. We report the study, by bioelectrical impedance analysis (BIA), of water composition changes after dietary salt manipulations both before and during CsA treatment of psoriatic patients. Ten normotensive psoriatic patients, ages 37 +/- 12 years (range, 19 to 54), with normal renal function were included. Each patient was assessed by BIA in 2 phases, before (phase 1) and during (phase 2) CsA therapy (3 mg/kg/day). In both phases, each patient was assessed in basal conditions (basal1 and basal2), on day 7 of a low-sodium diet (LS1 and LS2; 20 mEq/day) and on day 7 of a high-sodium diet (HS1 and HS2; 350 mEq/day). Plasma creatinine (Pcr), urinary volume excretion (Uv), urinary sodium (UNa+), urinary potassium (UK+), urinary osmolality (UOsmo), weight (Wt), resistance (R), reactance (Xc), total body water (TBW), extracellular water (ECW), intracellular water (ICW), Na:K exchangeable (Nae:Ke), phase angle (PA), and body cell mass (BCM) were evaluated. Blood pressure was monitored during 24 hours on the last day of each diet. Paired Student's t-test was used to analyze the different phases. Before CsA treatment, Wt, TBW and Nae:Ke were lower during LS1 than during basal1, whereas TBW was higher during HS1 than during LS1. During CsA, Wt, TBW, ECW, and Nae:Ke were lower during LS2 than during basal2, whereas ICW and PA were higher during LS2 than during basal2. HS2 showed higher TBW, ECW, and Nae:Ke and lower ICW, PA, and BCM than during LS2. Systolic blood pressure was higher during HS2 than during LS2 or HS1. In addition, diastolic blood pressure was higher during HS2 than during HS1. Body hydration status was more sensitive to dietary salt fluctuations during CsA treatment than without CsA, and a high-sodium diet seemed to enhance the CsA-induced hypertension side effect. Moreover, patients on low sodium intake under CsA treatment displayed neither any disturbance of body water composition nor any blood pressure change. Our data suggest that a low sodium intake might be very useful in preventing undesirable pressure and volume changes brought about by CsA treatment.

Body water distribution in severe obesity and its assessment from eight-polar bioelectrical impedance analysis.

To measure body water distribution and to evaluate the accuracy of eight-polar bioelectrical impedance analysis (BIA) for the assessment of total body water (TBW) and extracellular water (ECW) in severe obesity. Cross-sectional study. Obesity clinic. In all, 75 women aged 18-66 y, 25 with body mass index (BMI) between 19.1 and 29.9 kg/m(2) (ie not obese), 25 with BMI between 30.0 and 39.9 kg/m(2) (ie class I and II obese), and 25 with BMI between 40.0 and 48.2 kg/m(2) (ie class III obese). TBW and ECW were measured by (2)H(2)O and Br dilution. Body resistance (R) was obtained by summing the resistances of arms, trunk and legs as measured by eight-polar BIA (InBody 3.0, Biospace, Seoul, Korea). The resistance index at a frequency of x kHz (RI(x)) was calculated as height (2)/R(x). ECW : TBW was similar in women with class III (46+/-3%, mean+/-s.d.) and class I-II obesity (45+/-3%) but higher than in nonobese women (39+/-3%, P<0.05). In a random subsample of 37 subjects, RI(500) explained 82% of TBW variance (P<0.0001) and cross-validation of the obtained algorithm in the remaining 38 subjects gave a percent root mean square error (RMSE%) of 5% and a pure error (PE) of 2.1 l. In the same subjects, RI(5) explained 87% of ECW variance (P<0.0001) and cross-validation of the obtained algorithm gave a RMSE% of 8% and a PE of 1.4 l. The contribution of weight and BMI to the prediction of TBW and ECW was nil or negligible on practical grounds. ECW : TBW is similar in women with class I-II and class III obesity up to BMI values of 48.2 kg/m(2). Eight-polar BIA offers accurate estimates of TBW and ECW in women with a wide range of BMI (19.1-48.2 kg/m(2)) without the need of population-specific formulae.

Changes in body water distribution during treatment with inhaled steroid in pre-school children

Summary. Primary objective: The study aimed to examine the changes in water distribution in the soft tissue during systemic steroid activity.Research design: A three-way cross-over, randomized, placebo-controlled, double-blind trial was used, including 4 weeks of fluticasone propionate pMDI 200 μg b.i.d. delivered via Babyhaler®, budesonide pressurized metered dose inhaler (pMDI) 200 μg b.i.d. delivered via Nebuchamber® and placebo. Spacers were primed before use. In total, 40 children aged 1–3 years, with mild intermittent asthma were included. Twenty-five of the children completed all three treatments. At the end of each treatment period body impedance and skin ultrasonography were measured.Methods and procedures: We measured changes in water content of the soft tissues by two methods. Skin ultrasonography was used to detect small changes in dermal water content, and bioelectrical impedance was used to assess body water content and distribution.Main outcomes and results: We found an increase in skin density of the shin from fluticasone as measured by ultrasonography (p = 0.01). There was a tendency for a consistent elevation of impedance parameters from active treatments compared to placebo although overall this effect was not statistically significant (0.1<p<0.2). However, sub-analyses indicated a significant effect on whole-body and leg impedance from budesonide treatment (p<0.05).Conclusion: Decreased growth during inhaled steroid treatment seems to partly reflect generalized changes in body water.

Cold-water acclimation does not modify whole-body fluid regulation during subsequent cold-water immersion

We investigated the impact of cold-water acclimation on whole-body fluid regulation using tracer-dilution methods to differentiate between the intracellular and extracellular fluid compartments. Seven euhydrated males [age 24.7 (8.7) years, mass 74.4 (6.4) kg, height 176.8 (7.8) cm, sum of eight skinfolds 107.4 (20.4) mm; mean (SD)] participated in a 14-day cold-water acclimation protocol, with 60-min resting cold-water stress tests [CWST; 18.1 (0.1) degrees C] on days 1, 8 and 15, and 90-min resting cold-water immersions [18.4 (0.4) degrees C] on intervening days. Subjects were immersed to the 4th intercostal space. Intracellular and extracellular fluid compartments, and plasma protein, electrolyte and hormone concentrations were investigated. During the first CWST, the intracellular fluid (5.5%) and plasma volumes were reduced (6.1%), while the interstitial fluid volume was simultaneously expanded (5.4%). This pattern was replicated on days 8 and 15, but did not differ significantly among test days. Acclimation did not produce significant changes in the pre-immersion distribution of total body water, or changes in plasma osmolality, total protein, electrolyte, atrial natriuretic peptide or aldosterone concentrations. Furthermore, a 14-day cold-water acclimation regimen did not elicit significant changes in body-fluid distribution, urine production, or the concentrations of plasma protein, electrolytes or the fluid-regulatory hormones. While acclimation trends were not evident, we have confirmed that fluid from extravascular cells is displaced into the interstitium during acute cold-water immersion, both before and after cold acclimation.

Body water distribution and disease.

The study of body water distribution between extra- and intra-cellular spaces has the potential to improve our knowledge on the mechanisms of disease. A major challenge is that of establishing whether commonly detected subclinical alterations of body water distribution have prognostic or clinical implications.