Total Body Water Volume Research Articles

Ultrasonographic Evaluation of Systemic Venous Congestion in Maintenance Hemodialysis Patients during Fluid Removal

Introduction: Fluid overload is a frequent and serious complication in hemodialysis patients. The combination of multiple point-of-care ultrasound (POCUS) measurements can identify significant venous congestion, but its usefulness to determine ultrafiltration (UF) requirements and dry weight is unknown. Therefore, we evaluated prospectively patients in maintenance hemodialysis to establish the correlations between changes in venous congestion parameters and fluid removal. Methods: This was a prospective, single-center, observational study. POCUS venous congestion measurements were performed in 22 patients during 32 online post-dilutional hemodiafiltration sessions, and findings were correlated with UF volume, central venous pressure, and body water composition determined by multifrequency bioelectric impedance analysis (BIA). Results: The pre-dialysis weight was on average 1.9 kg above the BIA estimated dry weight, the average initial inferior vena cava (IVC) diameter was <2 cm. An initial abnormal hepatic vein (HV) waveform was present in 26% (8) of the measurements. The average UF volume was 2,084 ± 655 mL and correlated with changes in IVC diameter (R = 0.34, 95% CI: [0.18, 0.56], p < 0.05) but not with any other POCUS venous congestion parameters. Normalization of the IVC diameter and HV waveform was observed during the first UF hour in all initially altered measurements. Diameter reduction in the IVC correlated with total body water volume reduction estimated with BIA when measured immediately after fluid removal (R = 0.34, 95% CI: [0.08, 0.56], p < 0.05). Conclusion: Reduction in IVC diameter had a modest but significant correlation with UF volume in our patients on maintenance hemodiafiltration. POCUS may be used to monitor patients during UF.

Use of Bioimpedance Spectroscopy for Postoperative Fluid Management in Patients Undergoing Cardiac Surgery with Cardiopulmonary Bypass

ObjectiveTo assess whether bioimpedance spectroscopy analysis (BIA) can be used as a potential tool to guide postoperative fluid management in patients who undergo cardiac surgery. DesignAn observational study. SettingA single, tertiary hospital. ParticipantsPatients who underwent cardiac surgery with cardiopulmonary bypass between June to November 2023 who were able to undergo BIA measurements. InterventionsNone. Measurements and Main ResultsCorrelations between BIA measurements of extracellular fluid (ECF) and total body water (TBW) volumes and daily changes in weight and 24-hour net intake and output (I/O) of fluids were assessed. Correlations between pre-discharge ECF volume as a percentage of TBW volume (ECF%TBW) and pre-discharge Pro-BNP (Pro-BNP) levels and readmissions were analyzed. Changes in daily ECF volume significantly correlated with daily weight changes (p<0.01) and 24-hr I/O (p<0.01). TBW volume significantly correlated with daily weight changes (p<0.01) and with 24-hr I/O (p=0.04). Daily weight changes did not correlate with 24-hr I/O (p=0.06). The patients with pre-discharge ECF%TBW(%) greater than or equal to 51 had significantly higher pre-discharge Pro-BNP than those with ECF%TBW(%) less than 51 (p<0.01). Patients who had heart failure revisits or admissions after discharge had a higher pre-discharge ECF%TBW(%) on index admission compared to patients that did not have heart failure readmissions (p=0.01). ConclusionsUtilization of BIA measurements in postoperative cardiac surgery patients may be a valuable tool to quantitatively determine fluid status to help guide fluid management in this patient population. Further studies validating the use of BIA for postoperative care in this population are warranted.

Integrating classification and regression learners with bioimpedance methods for estimating weight status in infants and juveniles from the southern Cuba region

ObjectiveThe search for other indicators to assess the weight and nutritional status of individuals is important as it may provide more accurate information and assist in personalized medicine. This work is aimed to develop a machine learning predictions of weigh status derived from bioimpedance measurements and other physical parameters of healthy younger volunteers from Southern Cuba Region.MethodsA pilot random study at the Pediatrics Hospital was conducted. The volunteers were selected between 2002 and 2008, ranging in age between 2 and 18 years old. In total, 776 female and male volunteers are studied. Along the age and sex in the cohort, volunteers with class I obesity, overweight, underweight and with normal weight are considered. The bioimpedance parameters are obtained by measuring standard tetrapolar whole-body configuration. The bioimpedance analyser is used, collecting fundamental bioelectrical and other parameters of interest. A classification model are performed, followed by a prediction of the body mass index.ResultsThe results derived from the classification leaner reveal that the size, body density, phase angle, body mass index, fat-free mass, total body water volume according to Kotler, body surface area, extracellular water according to Kotler and sex largely govern the weight status of this population. In particular, the regression model shows that other bioparameters derived from impedance measurements can be associated with weight status estimation with high accuracy.ConclusionThe classification and regression predictive models developed in this work are of the great importance to assist the diagnosis of weigh status with high accuracy. These models can be used for prompt weight status evaluation of younger individuals at the Pediatrics Hospital in Santiago de Cuba, Cuba.

Edelman Gamblegrams: a tool to teach and learn disorders of water/plasma tonicity homeostasis.

This article introduces an innovative teaching and learning tool called "Edelman Gamblegrams" that aims to help medical learners better understand disorders related to water/plasma tonicity homeostasis, i.e., hyponatremia and hypernatremia. Gamblegrams, named after physician James L. Gamble, are bar diagrams displaying the relative abundance of extracellular anions and cations and are commonly used in the analysis of acid-base disorders. The Edelman equation represents the physiological variables that determine plasma sodium concentration, namely, total body sodium mass, total body potassium mass, and total body water volume. Edelman Gamblegrams inspired by traditional Gamblegrams but using the components of the Edelman equation, visually demonstrate how sodium, potassium, and water contribute to plasma sodium concentration under normal and pathological conditions. Scenarios that lead to hypotonic hyponatremia and hypernatremia in Edelman Gamblegrams are also discussed. Furthermore, examples of how these visual aids can enhance understanding of the pathogenesis of dysnatremias are also presented. Overall, the use of Edelman Gamblegrams has the potential to improve comprehension and retention of concepts related to water/plasma tonicity homeostasis.NEW & NOTEWORTHY This article introduces a new teaching tool called "Edelman Gamblegrams," modeled after the conventional Gamblegrams used in acid-base disorder analysis and using the independent physiological variables that determine the plasma sodium concentration (Edelman equation), that aims to help medical learners understand disorders related to water/plasma tonicity homeostasis.

ПОЛОВЫЕ ОСОБЕННОСТИ ПОКАЗАТЕЛЕЙ ФИЗИЧЕСКОГО РАЗВИТИЯ В ПЕРИОД ОБУЧЕНИЯ КУРСАНТОВ В ВОЕННОМ ВУЗЕ

Studying the patterns of dynamics of the body component composition of practically healthy individuals, using the example of the cadets’ adaptation to study at a military university, should be conducted on the basis of a multicriteria assessment using a set of statistical techniques. The purpose of the study is to identify gender–related correlational pleiades of indicators and assess their contribution to the adaptation of the body component composition of boys and girls to training in a military educational organization. A related sample of 387 male and 27 female cadets was examined during the period of their studies at 1-6 years. The body component composition was measured using the Tanita MС-780 MA body component analyzer. Correlational pleiades were formed based on the data obtained. The reliability of the impact of training at a military university, gender and their combined effect were evaluated using two-factor analysis of variance. The sexual characteristics of adaptation to training at a military university are associated with the formation of two alternative complexes of interrelated parameters. In men, changes in the body component composition during adaptation are associated with BMI, and in women with the total body water volume. In addition, in male cadets of a military university, the adipose tissue of the upper extremities plays an important negative role, as indicated by the correlation with the pulse. Studying at a military university, regardless of gender, gradually develops such indicators as trunk muscle mass and physical development rating, as well as stops the growth of visceral fat and BMI due to age-related changes. The obtained data demonstrate that, as a genderindependent marker of successful adaptation of the body component composition to training at a military university, it is possible to use the trunk muscle mass and the rating of physical development. Men's adaptation is best characterized by the dynamics of BMI, women's one is characterized by total body water volume.

Comparison of Bioelectrical Impedance Analysis (BIA)-Derived Parameters in Healthy Volunteers and Critically Ill Patients.

To compare bioelectrical impedance analysis (BIA)-derived parameters in healthy volunteers and critically ill patients and to assess its prognostic value in an ICU patient cohort. Retrospective, observational data analysis. Single centre, tertiary-level ICU (Ziekenhuis Netwerk Antwerpen, ZNA Stuivenberg Hospital). 101 patients and 101 healthy subjects, participants of International Fluid Academy Days. Compared to healthy volunteers, both male and female ICU patients had significantly higher values for total body water (TBW), extracellular water (ECW), extracellular fluid (ECF), plasma, and interstitial fluid volumes. The phase angle was significantly lower and the malnutrition index was significantly higher in ICU patients, regardless of gender. Non-survivors in the ICU had significantly higher extracellular water content (ECW, 50.7 ± 5.1 vs. 48.9 ± 4.3%, p = 0.047) and accordingly significantly lower intracellular water (ICW, 49.2 ± 5.1 vs. 51.1 ± 4.3%, p = 0.047). The malnutrition index was also significantly higher in non-survivors compared to survivors (0.94 ± 0.17 vs. 0.87 ± 0.16, p = 0.048), as was the capillary leak index (ECW/ICW). Compared to healthy volunteers, this study observed a higher malnutrition index and TBW in ICU patients with an accumulation of fluids in the extracellular compartment. ICU non-survivors showed similar results, indicating that ICU patients and a fortiori non-survivors are generally overhydrated, with increased TBW and ECW, and more undernourished, as indicated by a higher malnutrition index.

Exercise-Induced Fluid Retention, Cardiac Volume Overload, and Peripheral Edema in Ultra-Distance Cyclists

IntroductionUltracyclists expose themselves to extreme physical challenges. This study aimed to elucidate the effects of ultracycling on electrolyte and fluid balance and investigate the potential occurrence of peripheral edema. MethodsSerial laboratory analyses of blood and urine, bioelectrical impedance analyses and echocardiography were performed at four time points during a six-day bicycle ride in 13 ultracyclists (5 female, 8 male). Throughout the ride, participants continuously tracked fluid intake, measured extremity circumferences daily, and self-tested urinary electrolytes using a point-of-care testing device. Portrait photos were judged by 20 physicians for occurrence of facial and eyelid edema. ResultsParticipants covered a mean distance of 1,205 km and 19,417 vertical meters. From baseline to day 6, body weight remained stable (p = 0.479), but body composition changed with increasing total body water (+1.98 L ± 1.37, p = 0.003) and plasma volume (+18.86 % ± 10.7, p < 0.001). A significant increase in NT-proBNP (+297.99 ng/L ± 190.42, p < 0.001) until day 6 indicates concomitant cardiac volume overload. Swelling of face and eyelids peaked on day 5 (both p ≤ 0.033). On recovery, changes partly resolved. While urinary sodium concentration showed a nadir on day 4 (-32.18 mmol/L ± 23.88, p = 0.022), plasma osmolality (+5.69 mmosmol/kg ± 5.88, p = 0.004) and copeptin (+38.28 pg/mL ± 18.90, p < 0.001) increased steadily until day 6. ConclusionUltracycling over multiple days induces extracellular volume expansion, peripheral edema and cardiac volume overload. Renal sodium and water retention is likely contributing to this condition.

Comparison of Body Composition Changes and Non-Contact Musculoskeletal Injuries Among Professional First-Class Cricket Pace Bowlers

Background. Pace bowling is the most injury susceptible position in cricket due to repeated high intensity maneuvers. Previous studies on pace bowlers have considered anthropometric, biomechanical, and kinesiological factors for deciphering the injury etiology. Study purpose. The purpose of this study was to prospectively investigate the association of body composition parameters with the incidence of musculoskeletal injuries among pace bowlers in cricket. Materials and methods. A total of 44 healthy professional male pace bowlers (N=44; Age: 22.89±4.5 years; Height: 176±9 cm; Body weight: 76.34±8.09 kg; BMI: 21.4±3.1) were recruited from various cricket academies. They were assessed on anthropometrics, body composition, and aerobic fitness before the start of Indian cricket season (typically mid-September). Any non-contact sports injury accounting for significant time loss during the season was recorded followed by assessment of change in body composition status among injured and non-injured pace bowlers. Results. We found hamstring injury as the most prevalent injury (05/12). Lower back injury accounted for highest severity with time loss of 48 matches. Injured pace bowlers underwent higher training volume (hours/day; p=.009) prior to injury incidence, were significantly heavier, and had greater volume of total body water. All the pace bowlers gained significant amount of fat-free mass (FFM) from pre- to post-season. Conclusions. Higher training workload and higher body weight were associated with more injury risk among pace bowlers. Further research accommodating other predictive factors of body composition and psychomotor learning must be carried out to precisely predict injury risk among pace bowlers in cricket.

Plasma concentration of prophylactic cefazolin best correlates with lean body mass measured by bioimpedance analysis in lumbar spine surgery: Results of a pilot study

The aim of this study was to determine the association between measures of body composition and the concentration of plasma and paraspinal muscle cefazolin. Secondly, we aimed to confirm the efficacy of our hospital dosing regimen in achieving the minimum inhibitory concentration (MIC) at the surgical site. Patients undergoing posterior-based lumbar spine surgery had body composition analysed using bioimpedance analysis. All received 2 g of cefazolin at anaesthetic induction in line with hospital guidelines. Cefazolin concentration was measured in plasma (30-minites) and muscle (30- and 60-minuites) using high-performance liquid chromatography. 20 patients were recruited (mean age 61.5 years; 12 female). Mean plasma cefazolin concentrations were 34.1 +/− 10.2 mg/L; mean muscle concentrations 44.4 +/− 18.6 mg/kg and 43.8 +/− 20.4 mg/kg at 30- and 60-minutes respectively. Univariate analysis showed significant correlation between plasma cefazolin concentration and lean mass weight, absolute body weight, height, dry lean mass, total water, total body water, extracellular and intracellular water volume. Linear regression analysis showed lean mass weight the best predictor of plasma cefazolin concentration. Muscle cefazolin concentration was dependent on the plasma concentration. Using a MIC of 2 mg/L and 2 mg/kg for Staphylococcus aureus, MIC was achieved in all samples. In summary, plasma cefazolin concentration was best predicted by lean body mass. Further work should consider the influence of body composition on antibiotic delivery in extremes of body mass index. Local hospital guidelines are effective at achieving MIC against S. aureus.

#4969 AN ADEQUATE HYDRATION MANAGEMENT IMPROVES THE EFFICIENCY OF INTRADIALYTIC PHOSPHATE REMOVAL

Abstract Background and Aims The excess of phosphate (P) is one of the major risk factors for death in patients undergoing hemodialysis (HD). Improving P removal efficiency should ameliorate their prognosis. We previously reported, increased urea nitrogen (UN) removal efficiency results in increased the removal efficiency of P from extracellular fluid (ECF), but did not improve that from intracellular fluid (ICF) (NDT, Vol 35, Sup3, P1401, 2020). We also reported that P removal from ICF accounted for in average about 44% of total intradialytic P removal. For improving total P removal efficiency, removal efficiency of P from ICF should be increased. As P is one of the major osmotic agents in ICF, water outflow from ICF will accompany P outflow. We explored correlation between intracellular P removal and intracellular water (ICW) reduction. And we also sought for the strategy which efficiently derive water from ICF in HD patients in order to increase intracellular P removal. Method Eighty-six patients undergoing 4-hour HD were enrolled this study. ICW, extracellular water (ECW) volume and body fat mass (BFM) in each patient were measured with biochemical impedance analysis method before and after HD session. Total body water (TBW) was calculated by ICW + ECW. The amount of intradialytic P removal from ICF and from ECF in each patient was calculated as previously reported (NDT, Vol 35, Sup3, P1401, 2020). The correlation between the amount of intradialytic P removal from ICF and the amount of ICW reduction was investigated. All patients were divided into three groups according to the amount of ICW reduction as high reduction (HR) group, middle reduction (MR) group and low reduction (LR) group. The amount of P removal from ICF was compared between these groups. ICW volume change (ΔICW%) was calculated as (preICW – postICW)/preICW in each patient. Where preICW = ICW volume at the starting of HD, postICW = ICW volume at the end of HD. Circulating plasma volume change (ΔCPV%) was calculated as (postTP – preTP)/postTP in each patient. Where postTP = serum total protein concentration (TP) at the end of HD, preTP = TP at the end of HD. Lean body mass (LBM) was calculated as BW – BFM. Body weight (BW) change (ΔBW%), LBM change (ΔLBM%) and TBW volume change (ΔTBW%) were calculated in the same way as ΔICW%. To seek factors that effectively reduce ICW, the correlation with ΔICW% in ECW/TBW ratio, ΔCPV%, ΔCPV%/ΔBW% ratio, ΔCPV%/ΔLBM% ratio and ΔCPV%/ΔTBW% ratio was examined. Results The amount of intradialytic P removal from ICF positively correlated to the amount of ICW volume reduction (R = 0.279, y = 66.3x+285, p = 0.0076). It indicates an average of 66.3mg of P was removed from ICF per 1L of ICW reduction. In HR group, the amount of P removal from ICF was significantly larger than that in LR group (315.6±117.8mg vs 383.7±121.7mg, p = 0.019). ΔICW% negatively correlated to ECW/TBW ratio (R = 0.481, p = 0.000057). High ECW/TBW ratio indicates excess of ECW, which suggests having edema. ΔICW% positively correlated to ΔCPV% (R = 0.511, p = 0.0000051). Low ΔCPV% suggests insufficient of ultrafiltration. ΔICW% negatively correlated to ΔCPV%/ΔTBW% ratio (R = 0.421, p = 0.00011). High ΔCPV%/ΔTBW% ratio indicates insufficient plasma refilling for ultrafiltration rate, which suggests overrate of ultrafiltration. But ΔICW% did not correlate to ΔCPV%/ΔBW% ratio (R = 0.184, p = 0.10) nor ΔCPV%/ΔLBM% ratio (R = 0.176, p = 0.12). Conclusion The amount of intradialytic P removal from ICF correlated to the amount of ICW reduction. For efficient reduction of ICW, low ECW/TBW ratio, high ΔCPV% and low ΔCPV%/ΔTBW% ratio were required. It was suggested that efficient P removal was achieved when non-edematous patients get ultrafiltration of appropriate rate and dose.

A Pilot Comparative Study of Submerge vs. Non- Submerg Saturated Salt Solution Human Cadavers Embalming Method by Gross, Histological, and Microbiological Evaluation

Objective: To investigate and develop the saturated salt embalming method and evaluate the cadavers.Materials and Methods: Eight cadavers were embalmed with a saturated salt solution (SSS) by submerged (SG, N=2) and non-submerged (NSG, N=6), then evaluated by gross dissection, which compared to living humans, fresh and Thiel’s cadavers. The histological evaluation was compared to textbook pictures. The assessments were recorded on a Likert scale from 0 (no resemblance) to 5 (most resemblance). Pre-and post-embalming swabs were collected for bacterial and fungal cultures and lung tissues for acid-fast staining and mycobacterial cultures. Comparisons between the evaluated items were performed using the Kruskal–Wallis test. The Likert scale results were reported by percentage.Results: The submerge method (N=2) was terminated after three months of embalming because it showed insufficient quality for dissection. Six cadavers in NSG had gross tissue qualities that resembled living humans or fresh cadavers on a scale of 3 or 4. NSG had excellent joint flexibility. The histological tissues showed similarity to textbook pictures, with a scale of 4 or 5. There were bacterial and fungal cultures at the end of embalming. The pathogenic bacteria were Clostridium perfringens and Pseudomonas aeruginosa. Mycobacterium cultures were negative.Conclusion: Injected SSS, 80% total body water volume, is a promising embalming method that yields cadavers with high tissue quality, flexible joints, and good histological structures. However, this technique cannot eliminate bacteria and normal flora. It may result from the tropical climate setting.

Water Distribution Changes in Complex Decongestive Treatment for Leg Lymphedema: Quantitative Evaluation by Direct Segmental Multi-Frequency Bioimpedance Analysis.

Background: There is a need for a simple method for the quantitative evaluation of lymphedema swelling. In this study, we performed a direct segmental multi-frequency impedance analysis in patients with leg lymphedema.Methods: The subjects were 36 patients (6 men and 30 women) with 46 lymphedema legs. The average age was 61 years. All patients had International Society of Lymphology stage II lymphedema. Swelling ratio and ultrasound subcutaneous tissue echo-free space (FS) were examined. InBody 770 was used to measure the extracellular water (ECW), intracellular water (ICW), and total body water (TBW) volumes. Changes before and after complex decongestive treatment (CDT) were examined.Results: In 26 unilateral cases, the ECW, ICW, and TBW volumes of the affected legs were higher than those of the contralateral unaffected legs, and the ECW/TBW ratio was significantly higher in the affected legs (0.41) than in the contralateral unaffected legs (0.391). There was a significant correlation between the leg swelling ratio and the ECW/TBW ratio between the affected and contralateral unaffected legs (correlation coefficient=0.882). Ultrasound findings of the 46 affected legs were classified into no FS (group 0), minimal or only horizontal FS (group 1), and cobblestone-like FS (group 2). The ECW/TBW ratio of the affected legs in each group was 0.393 (14 legs), 0.407 (10 legs), and 0.426 (22 legs) respectively, demonstrating significant differences among the 3 groups. After CDT, the amount of water decreased in the affected legs and increased in the trunks and both upper limbs. The ECW/TBW ratio decreased significantly, from 0.432 to 0.414 in the affected legs, from 0.401 to 0.392 in the unaffected legs, and from 0.413 to 0.402 in the trunks. The ECW/TBW ratio had not changed and remained below 0.4 in the upper limbs.Conclusion: The segmental water contents measured by direct segmental multi-frequency impedance analysis correlates well with the degree of lymphedema swelling, and subcutaneous echo findings and can demonstrate water distribution change before and after CDT, which is considered to be a useful quantitative evaluation method for lymphedema. (This is secondary publication from Jpn J Phlebol 2020; 31(1): 1–7.)

Modelling sodium requirements of athletes across a variety of exercise scenarios – Identifying when to test and target, or season to taste

ABSTRACT Evidence suggests the focus for sodium replacement during exercise should be maintenance of plasma sodium concentration ([Na+]plasma) for any given total body water (TBW) volume. The sodium intake to achieve stable [Na+]plasma given known fluid and electrolyte intakes and losses can be mathematically estimated. Therefore the aim of this investigation was to model sodium requirements of athletes during exercise, observing the influence of sweat rate, exercise duration, body mass, baseline [Na+]plasma and sweat potassium [K+]sweat, and relevance to competition (soccer, elite marathon, and 160 km ultramarathon running). Models were constructed across a range of sweat sodium concentrations ([Na+]sweat) (20–80 mmol·L−1), sweat rates (0.5–2.5 L·h−1) and fluid replacement (10–90% of losses). In the competition-specific scenarios, fluid replacement was calculated to achieve 2% TBW losses. Sodium requirements were driven by fluid replacement (% of losses) and [Na+]sweat, with minimal or no influence of other variables. Replacing sodium was unnecessary in all realistic scenarios modelled for a soccer match and elite marathon. In contrast, the 160 km ultramarathon required ≥47% sodium replacement when [Na+]sweat was ≥40 mmol·L−1 and >80% of fluid losses were replaced. In conclusion, sodium requirements to maintain stable [Na+]plasma during exercise depend on both the proportion of fluid losses replaced, and [Na+]sweat. Only when prolonged exercise is coupled with aggressive fluid replacement (>80%) and whole body [Na+]sweat ≥40 mmol·L−1 does sweat composition testing and significant, targeted sodium replacement appear necessary. Highlights Modelling sodium intake requirements with sodium and fluid intake expressed as a proportion of losses, allows robust models to be constructed that are not influenced by sweat rate, exercise duration, body mass, and only to a minor extent by baseline plasma sodium and sweat potassium. When applied to specific sporting scenarios, targeted sodium replacement, and therefore sweat composition testing, appears unnecessary in all realistic scenarios modelled for a soccer match or elite marathon race. Athletes can therefore choose sodium intake according to taste preferences rather than physiological need. During a 160 km ultramarathon, targeted sodium replacement may be necessary because fluid replacement needs are greater as a proportion of losses. However the required quantity remains <50% of losses unless sweat rate is ≥1.5 L·hr−1, sweat sodium is ≥40 mmol·L−1, and fluid replacement is ≥90% of losses. The modelling technique described could be utilised by researchers to personalise sodium replacement in intervention studies for each participant, or by practitioners to either estimate the likely sodium needs of athletes during exercise, or to decide when sweat composition testing is or is not likely to be useful.

MO907: Predictors of Negative Outcomes in HDF-OL Patients: A Cohort Study

BACKGROUND AND AIMSHaemodiafiltration on-line (HDF-ol), an effective mode of replacement therapy for stage 5 chronic kidney disease (CKD 5D), cannot be considered sufficiently studied in terms of its effect on the outcomes. Our main aim was to identify a possible association between individual anthropometric, laboratory data and parameters of the prescribed treatment regimen with the best survival rate when using the HDF-ol mode.METHODA retrospective1 year analysis of the EuCliD database of 9986 patients treated with HDF-ol in 27 Fresenius Medical Care centres in Russia was carried out. All patients got post-dilution HDF-ol procedures at least 3 times a week, for at least 12 h a week with Kt/V at least 1.4. Data on alive (9616) and deceased (370) patients were compared by gender, age, treatment experience, body weight (BW), body mass index (BMI), body surface area (BSA), total body water volume (TBW), volume of urea distribution (V Urea BCM), presence of diabetes mellitus (DM), ischemic heart disease (CHD), chronic heart failure (CHF), as well as parameters of the procedure: effective weekly dialysis time, Kt/V, effective infusion volume (EIV) and effective convection volume (ECV).RESULTSDifferences in groups were found only for a part of parameters (Table 1).Table 1.Group of patientsStatisticAliveDeceasedP-valueBasic demographic characteristicsSex: f n (%)4422 (46.0%)140 (37.8%).0024Sex: m n (%)5194 (54.0%)230 (62.2%).0024Age (years) N 9616370<.0001Mean (SD)53.4 (13.6)58.8 (12.1)Median5560Min–max17.0–86.030.0–83.095% CI53.1–53.757.5–60.0BW (kg) N 9616370<.0001Mean (SD)75.2 (17.5)71.7 (16.5)Median73.470Min–max30.6–194.635.3–133.295% CI74.8–75.570.0–73.4BMIMean (SD)26.7 (5.7)25.5 (5.7)<.0001Median2625Min–max14.1–53.213.4–47.295% CI26.6–26.924.9–26.1CHD: yes n (%)1565 (16.3%)98 (26.5%)<.0001CHD: no n (%)8051 (83.7%)272 (73.5%)<.0001HF: yes n (%)1878 (19.5%)94 (25.4%).0065HF: no n (%)7738 (80.5%)276 (74.6%).0065diabetes: yes n (%)1213 (12.6%)72 (19.5%).0002diabetes: no n (%)8403 (87.4%)298 (80.5%).0002Parameters of the HDF ol proceduresEffective week dialysis time (min)Mean (SD)784.2 (140.2)731.6 (372.2)<.0001Median790733,5Min–max150.0–4979.0197.0–4017.095% CI781.3–787.1689.6–773.6EIV (L)Mean (SD)24.6 (4.3)23.0 (4.7)<.0001Median23.722.4Min–max0.5–69.41.9–43.895% CI24.5–24.722.6–23.5ECV (L)Mean (SD)27.0 (4.4)25.3 (5.0)<.0001Median2624.7Min–max0.5–71.22.0–46.095% CI26.9–27.124.8–25.8OCM Kt/VMean (SD)1.7 (0.3)1.7 (0.3)<.0001Median1.71.6Min–max0.5–6.40.7–3.095% CI1.7–1.71.7–1.7The main laboratory parametersCalcium (mmol/L)Mean (SD)2.2 (0.2)2.3 (0.2)<.0001Median2.22.2Min–max1.0–3.71.5–3.095% CI2.2–2.22.2–2.3Albumin (g/L)Mean (SD)40.6 (3.2)38.7 (4.3)<.0001Median4139Min–max13.0–71.018.2–49.095% CI40.5–40.638.4–38.9b2-microglobulin (mg/L)Mean (SD)23.8 (7.0)25.2 (8.1)<.0001Median23.323.7Min–max1.5–80.05.4–85.195% CI23.8–23.924.7–25.7Haemoglobin (g/L)Mean (SD)110.4 (14.9)105.6 (17.9)<.0001Median111106Min–max12.0–176.034.0–167.095% CI110.2–110.5104.5-106.7CRP (mg/L)Mean (SD)7.8 (15.7)19.7 (43.3)<.0001Median3.46.6Min–max0.0–500.00.1–521.195% CI7.6–7.917.0–22.4Table 2.Hospitalization of ESKD patients before and after the onset of the COVID-19 pandemic in a tertiary University Hospital of Thessaloniki, GreeceBefore COVID-19 pandemicAfter COVID-19 pandemicP-valueTime period1 March 2019–29 February 20211 March 2020–28 February 2021-Hospitalizationsa (n)14990-Age (years)67.7 ± 13.665.3 ± 16.7247Gender (M/F)105/44 (70.5%/29.5%)62/28 (68.9%/31.1%)884Duration of hospitalization (days)7 (2–83)9 (2–67)0.423Outcome (n, %)0.837 Improvement127 (85.2%)76 (84.4%) Stable medical condition10 (6.7%)6 (6.7%) In-hospital death12 (8.1%)8 (8.9%) aHospitalizations due to SARS-CoV-2 infection over the pandemic period were not included in this comparative analysis.CONCLUSIONAssociation of risk of death in patients with CKD 5D treated with HDF-ol included male gender, older age, concomitant diseases (CHD, CHF, DM), lower BW and BMI, shorter effective weekly dialysis time, lower values of EIV and ECV, Kt/V, higher values of hypercalcemia, hypoalbuminemia, lower haemoglobin levels, higher levels of b2-microglobulin and CRP. Such indicators as TBW, VUrea BCM, BSA and the length of treatment on dialysis did not reached statistical significance when comparing alivе and deceased patients.

The effectiveness of on-line hemodiafiltration in patients with chronic kidney disease: risk factors and improving the assessment of fluid excretion values

Hemodiafiltration on-line (HDF OL) cannot be considered sufficiently studied in terms of its effect on the outcome. THE AIM. To identify the possible relationship of individual anthropometric, laboratory data and parameters of the prescribed treatment regimen with better survival when using the HDF OL. PATIENTS AND METHODS. A retrospective study of the EuCliD database of patients treated with HDF OL in 27 Fresenius Medical Care centers in the Russian Federation during 2014 was conducted. All patients received postdilution HDF OL procedures at least 3 times a week, lasting at least 12 hours a week, with adequacy of Kt/V procedures of at least 1,4. Data from survivors (9616) and deceased (370) patients were compared. The analyzed indicators were: gender, age, treatment experience, body weight, body mass index (BMI), body surface area (BSA), total body water volume (TBW), the volume of distribution (V Urea BCM), presence of diabetes mellitus, coronary heart disease, heart failure, as well as the parameters of the procedure: effective weekly dialysis time, Kt/V, effective in-fusion volume (EIV), effective convection volume (ECV). RESULTS. Risk factors for death in patients with CKD 5D treated with HDF OL include male gender, older age, con-comitant diseases, lower body weight, and BMI, shorter effective weekly dialysis time, lower EIV and ECV values, Kt/V, higher hypercalcemia, hypoalbuminemia, lower hemoglobin levels, higher b2-microglobulin levels, and CRP. Сomparing the normalized BMI, BSA, TBW, V Urea BCM indicators, we identified those that were associated with a high risk of mortality in the population of dialysis patients. CONCLUSION. As a result of this work, two normalized ratios were identified (the median ratio of effective infusion volume to body surface area and the median ratio of effective convection volume to body surface area), which were associated with a high risk of mortality in the population of dialysis patients.

The circulating renin-angiotensin-aldosterone system is down-regulated in dogs with glomerular diseases compared to other chronic kidney diseases with low-grade proteinuria

Glomerular diseases (GD) lead to a variety of disorders of the vascular and the total body water volumes. Various pathomechanisms, including vascular underfill and overfill, have been suggested to explain these disturbances. Accordingly, the circulating renin-angiotensin-aldosterone system (cRAAS) is expected to be activated as either a cause or a result of these fluid disorders. The aim of this study was to characterize the activity of the cRAAS in dogs with GD and to evaluate its relationship with the vascular volume status. In a prospective study, we evaluated the plasma renin activity and the serum aldosterone concentration in 15 dogs with GD. Their fluid volume status was estimated with clinical variables reflecting volemia and hydration, echocardiographic volume assessment, N-terminal pro B-type natriuretic peptide, blood urea nitrogen:creatinine ratio, and the urinary fractional excretion of sodium. Ten dogs with chronic kidney disease (CKD) with matching degree of azotemia were recruited as controls. The activity of the cRAAS was low in 10 dogs, normal in 3 dogs, high in 1 dog and equivocal (high renin—low aldosterone) in 1 dog with GD. These dogs had a lower cRAAS activity than dogs with CKD (p = 0.01). The clinical evaluation showed 8 hypovolemic and 7 non-hypovolemic dogs; 3 dehydrated, 9 euhydrated and 3 overhydrated dogs. The cRAAS activity was not different between hypovolemic and non-hypovolemic dogs. The down-regulated cRAAS without obvious association with the clinical volume status of these dogs with GD, suggests different mechanisms of fluid volume dysregulation in dogs with GD than previously assumed. This finding however should be confirmed in a focused larger scale study, as it may influence the use of cRAAS blockers as part of the standard therapy of GD in dogs.

Validation of the SMH Equations for the Estimation of the Total Body Water Volume in Hemodialysis Patients.

Online dialysis clearance monitors typically provide an accurate value for Kt. A value for V (total body water [TBW]) is required to calculate Kt/V, the measure of the adequacy of the delivered dialysis in hemodialysis (HD) patients. Using bioimpedance spectroscopy (BIS), we previously developed 2 sex-specific equations for the estimation of the TBW, which we have chosen to name the St Michael's Hospital (SMH) equations. The objective of this study was to validate the SMH equations in a second distinct population of patients. Cross-sectional study. Single center hemodialysis unit at St Michael's Hospital, a tertiary care teaching hospital, in Toronto, Canada. Eighty-one adult HD patients who had been receiving conventional maintenance HD for at least 3 months. Anthropometric measurements including weight, height, and waist circumference were collected. TBW was measured by BIS using the Body Composition Monitor (Fresenius Medical Care, Bad Homburg, Germany). The Bland-Altman method to calculate the bias and limits of agreement and the difference plot analysis were used to evaluate the difference between the BIS-TBW and the TBW derived from our equations (SMH equation) in this validation cohort. The TBW values based on our equations had a high correlation with BIS-TBW (correlation coefficients = 0.93, P values < .01, bias = 1.8 [95% CI: 1-2.6] liter). Application of SMH equations closely predicted Kt/V, based on BIS value, in all categories of waist circumference. Small sample size, single-center, not including peritoneal dialysis patients. A larger and more heterogeneous sample with more patients at the extremes of body mass index would allow for more detailed sub-group analyses in different races and different anthropometric categories to better understand the performance of these equations in discrete sub-groups of patients. In maintenance HD patients, our previously derived equations to estimate the TBW using weight and waist circumference appear to be valid in a distinct patient population. Given the centrality of TBW to the calculation of small molecule clearance, the SMH equations may enhance the measurement of dialysis adequacy and inform practice.

Accuracy of Bioimpedance Modalities for Fluid Assessment in Hemodialysis Patients: A Randomized Observational Study

Aim Fluid overload is a major contributor to mortality in critically ill patients but is difficult to estimate clinically. Bioimpedance has been used to estimate fluid volumes with three different methods of analysis:1. single-frequency; 2. multi-frequency; 3. bioimpedance spectroscopy. The aim of this study is to assess the accuracy of different types of bioimpedance analysis in detecting changes in fluid volumes. Methods Prospective observational study, in end-stage renal disease patients requiring dialysis, in a tertiary care center. During hemodialysis, we assessed the correlation between change in estimated total body water volumes, as measured by all three methods of bioimpedance, and fluid volumes removed, as measured by changes in body weight. Results Twenty-four pediatric and adult patients were included in the study (median age 42.4 years) with a total of 30 study assessments performed. There was a weak correlation between change in body weight and change in estimated total body water volumes (R=0.15, 0.41, and 0.38, respectively). In the Bland-Altman analysis, the mean biases along with their associated 95% confidence limits of agreement were -0.23 L (-4.1 to 3.5 L) for single-frequency; -1.1 L (-4.1 to 1.9 L) for multi-frequency; and -0.6 L (-6.1 to 4.8 L) for bioimpedance spectroscopy. Conclusion In this study of end-stage renal disease patients requiring dialysis, the accuracy of bioimpedance measurement to evaluate fluid changes was poor, regardless of bioimpedance modality.

A Novel Hypertension Management Algorithm Guided by Hemodynamic Data

A Novel Hypertension Management Algorithm Guided by Hemodynamic Data

Half the V by 120: A practical approach to the prevention of the dialysis disequilibrium syndrome.

The dialysis disequilibrium syndrome (DDS) results from osmotic shifts between the blood and the brain compartments. Patients at risk for DDS include those with very elevated blood urea nitrogen, concomitant hypernatremia, metabolic acidosis, and low total body water volumes. By understanding the underlying pathophysiology and applying urea kinetic modeling, it is possible to avoid the occurrence of this disorder. A urea reduction ratio (URR) of no more than 40%-45% over 2 h is recommended for the initial hemodialysis treatment. The relationship between the URR and Kt/V is useful when trying to model the dialysis treatment to a specific URR target. A simplified relationship between Kt/V and URR is provided by the equation: Kt/V=-ln (1 - URR). A URR of 40% is roughly equivalent to a Kt/V of 0.5. The required dialyzer urea clearance to achieve this goal URR in a 120-min treatment can simply be calculated by dividing half the patient's volume of distribution of urea by 120. The blood flow rate and dialyzer mass transfer coefficient (K0 A) required to achieve this clearance can then be plotted on a nomogram. Other methods to reduce the risk of DDS are reviewed, including the use of continuous renal replacement therapy.