• Dialysis
• Fluid overload
• Ultrasound

• Humans
• Echocardiography
• Electric Impedance
• Fluid Therapy/methods
• Kidney Failure, Chronic/physiopathology
• Kidney Failure, Chronic/therapy
• Renal Dialysis/methods
• Ultrasonography
• Water-Electrolyte Balance/physiology

This study, the sole randomized trial of its kind, proposes guidelines for fluid balance management in continuous KRT (CKRT) patients using bioimpedance. Despite this, bioimpedance analysis–guided volume management did not influence the proportion of patients achieving estimated euvolemia at 7 days into CKRT. Further investigation is needed to assess whether bioimpedance analysis guidance can facilitate rapid fluid removal in the early phase of CKRT for patients with AKI.

Ultrafiltration with continuous KRT (CKRT) can be used to manage fluid balance in critically ill patients with AKI. We aimed to assess whether bioimpedance analysis (BIA)–guided volume management was more efficacious than conventional management for achieving estimated euvolemia (e-euvolemia) in CKRT-treated patients.

In a multicenter randomized controlled trial from July 2017 to July 2020, the patients with AKI requiring CKRT were eligible if the weight at the start of CKRT had increased by ≥5% compared with the weight at the time of admission or total body water (TBW)/height (H)2 ≥13 L/m2. We randomly assigned 208 patients to the control (conventional fluid management; n =103) and intervention groups (BIA-guided fluid management; n =105). The primary outcome was the proportion of attaining e-euvolemia 7 days postrandomization. E-euvolemia was defined as the difference between TBW/H2 D7 and D0 was <−2.1 L/m2, or when TBW/H2 measured on D7 was <13 L/m2. The 28-, 60-, and 90-day mortality rate were secondary outcomes.

The primary outcome occurred in 34 patients in the intervention group and 27 in the control group (47% versus 41%; P = 0.50). The mean value of TBW/H2 measured on D7 was the same at 13.9 L/m2 in both groups. The differences between TBW/H2 D7 and D0 were −1.13 L/m2 in the intervention group and −1.08 L/m2 in the control group (P = 0.84). Patients in the intervention group had a significantly higher proportion of reaching e-euvolemia on D1 than those in the control group (13% versus 4%, P = 0.02). Adverse events did not differ significantly between the groups.

BIA-guided volume management did not affect the proportion of reaching the e-euvolemia at 7 days of the start of CKRT.

ClinicalTrials.gov , ID: NCT03330626 (Registered on November 6, 2017; seven study participants were retrospectively registered; nonetheless, Institutional Review Board approval of each institution was completed before study participant registration).

• aki

• HI17C1827 Korea Health Industry Development Institute

• bioimpedance analysis
• cardiology
• chronic patients
• heart failure
• kidney disease
• nephrology

• Humans
• Stroke Volume
• Electric Impedance
• Ventricular Function, Left
• Lung/diagnostic imaging
• Ultrasonography
• Renal Dialysis/adverse effects
• Heart Failure

• Bioimpedance
• Hemodialysis
• Hydration status

• Humans
• Uric Acid
• Water Intoxication
• Dehydration/diagnosis
• Body Water
• Electric Impedance
• Renal Dialysis
• Water

• dehydration detection
• hydration
• hydration monitoring
• medical device
• wearable devices

• Humans
• Aged
• Dehydration/diagnosis
• Water

• Bioimpedance spectroscopy (BIS)
• Fluid overload
• Hemodialysis
• Systolic BP

• Adolescent
• Body Water
• Child
• Electric Impedance
• Female
• Humans
• Intracellular Fluid/metabolism
• Renal Dialysis/adverse effects
• Spectrum Analysis
• Water-Electrolyte Balance

The phase angle (PhA) has been used as a nutritional marker and predictor of mortality in patients on peritoneal dialysis (PD). The coronary artery calcium (CAC) score has shown to predict the incidence of acute myocardial infarction and death from cardiovascular disease in these patients. However, the association between PhA and CAC score in patients with PD is not well-established, which is the objective of this study.

Cross-sectional study with patients on PD, followed up at a University Hospital, between March 2018 and August 2019. PhA was evaluated by unifrequency bioimpedance (BIA). The CAC score was calculated based on cardiovascular computed tomography, considering positive when greater than or equal to 100 Agatston and negative when less than 100 Agatston.

We evaluated 44 patients on dialysis, with a mean age of 56 years and median time on dialysis therapy was 11.7 months. In the statistical analysis, a significant association was only observed between the CAC score and the PhA.

The PhA is associated with a positive CAC score in patients with PD, and despite other factors, may be useful as a risk marker for coronary artery disease in this population.

• bioelectrical impedance
• coronary artery calcium score
• nutrition
• peritoneal dialysis
• phase angle

• dysnatremia
• hydrophilic compounds
• hypernatremia
• hyponatremia
• osmotic sodium inactivation

• bioimpedance
• creatinine index
• hemodialysis
• sarcopenia
• ultrasound

• Hypertension
• Hypothalamic-pituitary-adrenal axis
• Inflammation
• Sympathetic nervous system
• proANP

• dialysis
• heart failure
• total body fluid monitoring
• ultrafiltration
• wearables

Chronic volume overload is pervasive in patients on chronic haemodialysis and substantially increases the risk of cardiovascular death. The rediscovery of the three-compartment model in sodium metabolism revolutionizes our understanding of sodium (patho-)physiology and is an effect modifier that still needs to be understood in the context of hypertension and end-stage kidney disease. Assessment of fluid overload in haemodialysis patients is central yet difficult to achieve, because traditional clinical signs of volume overload lack sensitivity and specificity. The highest all-cause mortality risk may be found in haemodialysis patients presenting with high fluid overload but low blood pressure before haemodialysis treatment. The second highest risk may be found in patients with both high blood pressure and fluid overload, while high blood pressure but normal fluid overload may only relate to moderate risk. Optimization of fluid overload in haemodialysis patients should be guided by combining the traditional clinical evaluation with objective measurements such as bioimpedance spectroscopy in assessing the risk of fluid overload. To overcome the tide of extracellular fluid, the concept of time-averaged fluid overload during the interdialytic period has been established and requires possible readjustment of a negative target post-dialysis weight. ²³Na-magnetic resonance imaging studies will help to quantitate sodium accumulation and keep prescribed haemodialytic sodium mass balance on the radar. Cluster-randomization trials (e.g. on sodium removal) are underway to improve our therapeutic approach to cardioprotective haemodialysis management.

• bio-impedance spectroscopy
• cardiovascular disease
• haemodialysis
• sodium metabolism
• time-averaged fluid overload

• Bioimpedance analysis
• Inferior vena cava
• Lung ultrasound
• N-terminal pro-B-type natriuretic peptide
• Peritoneal dialysis
• Volume overload

• Body Composition
• Echocardiography
• Electric Impedance
• Humans
• Kidney Failure, Chronic/complications
• Kidney Failure, Chronic/mortality
• Kidney Failure, Chronic/therapy
• Lung/diagnostic imaging
• Natriuretic Peptide, Brain/blood
• Nephrology/methods
• Nephrology/trends
• Peritoneal Dialysis/adverse effects
• Predictive Value of Tests
• Prognosis
• Risk Assessment/methods
• Ultrasonography
• Vena Cava, Inferior/diagnostic imaging
• Water-Electrolyte Imbalance/blood
• Water-Electrolyte Imbalance/diagnosis
• Water-Electrolyte Imbalance/etiology
• Water-Electrolyte Imbalance/mortality

Fluid volume and hemodynamic management in hemodialysis patients is an essential component of dialysis adequacy. Restoring salt and water homeostasis in hemodialysis patients has been a permanent quest by nephrologists summarized by the ‘dry weight’ probing approach. Although this clinical approach has been associated with benefits on cardiovascular outcome, it is now challenged by recent studies showing that intensity or aggressiveness to remove fluid during intermittent dialysis is associated with cardiovascular stress and potential organ damage. A more precise approach is required to improve cardiovascular outcome in this high-risk population. Fluid status assessment and monitoring rely on four components: clinical assessment, non-invasive instrumental tools (e.g., US, bioimpedance, blood volume monitoring), cardiac biomarkers (e.g. natriuretic peptides), and algorithm and sodium modeling to estimate mass transfer. Optimal management of fluid and sodium imbalance in dialysis patients consist in adjusting salt and fluid removal by dialysis (ultrafiltration, dialysate sodium) and by restricting salt intake and fluid gain between dialysis sessions. Modern technology using biosensors and feedback control tools embarked on dialysis machine, with sophisticated analytics will provide direct handling of sodium and water in a more precise and personalized way. It is envisaged in the near future that these tools will support physician decision making with high potential of improving cardiovascular outcome.

This study compared nutritional parameters in hemodialysis (HD) subjects and controls using bioimpedance analysis (BIA) and investigated how BIA components changed before and after HD.

This cross-sectional study included 147 subjects on maintenance HD from two hospitals and 298 propensity score-matched controls from one healthcare center. BIA was performed pre- and post-HD at mid-week dialysis sessions.

Extracellular water/total body water (ECW/TBW) and waist-hip ratio were higher in the HD patients; the other variables were higher in the control group. The cardiothoracic ratio correlated best with overhydration (r = 0.425, P < 0.01) in HD subjects. Blood pressure, hemoglobin, creatinine, and uric acid positively correlated with the lean tissue index in controls; however, most of these nutritional markers did not show significant correlations in HD subjects. Normal hydrated weight was predicted to be higher in the pre-HD than post-HD measurements. Predicted ultrafiltration (UF) volume difference based on pre- and post-HD ECW/TBW and measured UF volume difference showed a close correlation (r² = 0.924, P < 0.01). Remarkably, the leg phase angle increased in the post-HD period.

The estimated normal hydrated weight using ECW/TBW can be a good marker for determining dry weight. HD subjects had higher ECW/TBW but most nutritional indices were inferior to those of controls. It was possible to predict UF volume differences using BIA, but the post-HD increase in leg phase angle, a nutritional marker, must be interpreted with caution.

• Bioimpedance
• Hemodialysis
• Lean tissue index
• Nutritional status
• Overhydration

Despite recent technical advances in the management of acute kidney injury (AKI), such as continuous renal replacement therapy (CRRT), intensive care unit mortality is still high, at approximately 40 to 50%. Although several factors have been reported to predict mortality in AKI patients, fluid overload (FO) during CRRT is a well-known predictor of patient survival. However, FO has been mostly quantified as an arithmetical calculation and determined on the basis of the physicians’ perception. Even though such quantification and assessment provides an easy evaluation of a patient’s fluid status and is a simple method, it is not applicable unless a detailed record of fluid monitoring is available. Furthermore, the method cannot differentiate excess water in individual water compartments but can only reflect excess total body water. Bioimpedance analysis (BIA) has been used to measure the nutritional component of body composition and is a promising tool for the measurement of volume status. However, there has been no prospective interventional study for fluid balance among CRRT-treated AKI patients using BIA. Therefore, we will investigate the usefulness of fluid management using the InBody S10 (InBody®, Seoul, Korea), a BIA tool, compared with that of generally used quantification methods.

This will be a multicenter, prospective, randomized controlled trial. A total of 244 patients undergoing CRRT treatment will be enrolled and randomly assigned to receive either to InBody S10-guided management or to fluid management based only on clinical information for 7 days. The primary outcome is to compare the rate of euvolemic status 7 days after the initiation of CRRT, with a secondary outcome being to compare the 28-, 60-, and 90-day mortality rates between the two groups.

This will be the first clinical trial to investigate the effect of using BIA-guided fluid management to achieve euvolemia in CRRT-treated AKI patients.

ClinicalTrials.gov, ID: NCT03330626. Registered on 6 November 2017.

The online version of this article (10.1186/s13063-018-3056-y) contains supplementary material, which is available to authorized users.

• Bioimpedance analysis (InBody S10 (InBody®) Seoul, Korea)
• Continuous renal replacement therapy (CRRT)
• Fluid balance

• Deglutition
• Dehydration
• Maxillary carcinoma
• Maxillectomy
• Swallowing disorders
• Thickining agents

• Bioimpedance
• haemodialysis
• multi-frequency
• single-frequency
• ultrafiltration

• Adult
• Aged
• Body Composition
• Body Water/metabolism
• Body Weight
• Electric Impedance
• Female
• Fluid Shifts
• Humans
• Kidney Diseases/diagnosis
• Kidney Diseases/metabolism
• Kidney Diseases/physiopathology
• Kidney Diseases/therapy
• Male
• Middle Aged
• Predictive Value of Tests
• Renal Dialysis/methods
• Reproducibility of Results
• Time Factors
• Treatment Outcome

Case series

Patient: Male, 24 • Female, 55 • Female, 56 • Male, 72

Final Diagnosis: Hypertension

Symptoms: Dyspnea

Medication: —

Clinical Procedure: Intravascular renal denervation

Specialty: Cardiology

Fluid retention is a common adverse event in patients who receive endothelin (ET) receptor antagonist therapy, including the highly selective ETA receptor antagonist, atrasentan.

We performed longitudinal assessments of thoracic bioimpedance in patients with type 2 diabetes mellitus and nephropathy to determine whether a decrease in bioimpedance accurately reflected fluid retention during treatment with atrasentan.

We conducted a randomized, double-blind, placebo-controlled study in 48 patients with type 2 diabetes mellitus and nephropathy who were receiving stable doses of renin angiotensin system inhibitors and diuretics.

Patients were randomized 1:1:1 to placebo, atrasentan 0.5 mg, or atrasentan 1.25 mg once daily for 8 weeks. Thoracic bioimpedance, vital signs, clinical exams, and serologies were taken at weeks 1, 2, 4, 6, and 8, with the exception of serum hemoglobin, which was not taken at week 1, and serum brain natriuretic peptide, which was only taken at baseline, week 4, and week 8.

Alterations in bioimpedance were more often present in those who received atrasentan than in those who received placebo, though overall differences were not statistically significant. Transient declines in thoracic bioimpedance during the first 2 weeks of atrasentan exposure occurred before or during peak increases in body weight and hemodilution (decreased serum hemoglobin).

We conclude that thoracic bioimpedance did not reflect changes in weight gain or edema with atrasentan treatment in this study. However, the sample size was small, and it may be of interest to explore the use of thoracic bioimpedance in a larger population to understand its potential clinical use in monitoring fluid retention in patients with chronic kidney disease who receive ET receptor antagonists.

• Aged
• Atrasentan
• Diabetes Mellitus, Type 2/complications
• Diabetes Mellitus, Type 2/drug therapy
• Diabetic Nephropathies/drug therapy
• Diuretics/therapeutic use
• Dose-Response Relationship, Drug
• Double-Blind Method
• Edema/chemically induced
• Electric Impedance
• Endothelin Receptor Antagonists/administration & dosage
• Endothelin Receptor Antagonists/adverse effects
• Female
• Humans
• Longitudinal Studies
• Male
• Middle Aged
• Pyrrolidines/administration & dosage
• Pyrrolidines/adverse effects
• Renin-Angiotensin System/drug effects
• Weight Gain/drug effects

• AbbVie

• Body composition monitor
• Dry weight
• Hemodialysis
• Hypertension

Overhydration (OH) is associated with mortality in chronic kidney disease (CKD). A relative overhydration adjusted for extracellular water (OH/ECW) measured by bioimpedance >15% has shown an increased mortality risk in haemodialysis but few studies have been developed in advanced CKD. Our objective was to evaluate the effect of OH on mortality in patients with Stage 4 or 5 non-dialysis CKD.

We performed a prospective study of 356 patients enrolled in 2011 and followed up until 2016. At baseline we collected general characteristics, serum inflammatory and nutrition markers, cardiovascular events (CVEs) and body composition using bioimpedance spectroscopy. During a median follow-up of 50 (24–66) months we collected mortality data.

The mean creatinine was 3.5 ± 1.3 mg/dL, median proteinuria was 0.5 [interquartile range (IQR) 0.2–1.5] g/24 h, median OH was 0.6 (IQR −0.4–1.5) L and mean relative OH (OH/ECW) was 2.3 ± 0.8%. We found that 32% of patients died. The univariate Cox analysis showed an association between mortality and age, diabetes, previous CVEs, Charlson comorbidity index, low albumin and pre-albumin, high C-reactive protein (CRP), low lean tissue and high OH/ECW. Multivariate Cox analysis confirmed an association between mortality and age {exp(B) 1.1 [95% confidence interval (CI) 1.0–1.3]; P = 0.001}, Charlson comorbidity index [exp(B) 1.1 (95% CI 1.0–1.2); P = 0.01], CRP [exp(B) 1.1 (95% CI 1.0–1.2); P = 0.04], OH/ECW [exp(B) 3.18 (95% CI 2.09–4.97); P = 0.031] and low lean tissue [exp(B) 0.82 (95% CI 0.69–0.98); P = 0.002]. Kaplan–Meier analysis confirmed higher mortality in patients with OH/ECW >0% (log rank 11.1; P = 0.001).

Any grade of relative OH measured by OH/ECW >0% is associated with long-term mortality in patients with Stage 4 or 5 non-dialysis CKD.

• bioimpedance
• cardiovascular events
• chronic kidney disease
• mortality
• overhydration

• Bioimpedance
• cardiovascular
• euvolemia
• peritoneal dialysis
• residual renal function

• Body fluids
• Body water
• Congestive heart failure
• Extracellular volume
• Hepatic cirrhosis
• Hypertonicity
• Hypotonicity
• Nephrotic syndrome
• Sepsis

• R01 HL105649 NHLBI NIH HHS
• U01 HL071556 NHLBI NIH HHS
• F32 DK009924 NIDDK NIH HHS
• R01 HL109015 NHLBI NIH HHS
• U01 DK099914 NIDDK NIH HHS
• R01 DK073665 NIDDK NIH HHS

• Bioimpedance
• Children
• Fluid Status
• Hemodialysis

• Adolescent
• Body Composition
• Body Weight
• Child
• Child, Preschool
• Edema/etiology
• Electric Impedance/adverse effects
• Female
• Humans
• Hypertension/etiology
• Male
• Organism Hydration Status
• Renal Dialysis
• Young Adult

• Ministry of Health and Welfare
• Fresenius Medical Care

Intra-abdominal fat is an important factor in determining the metabolic syndrome/insulin resistance, and thus the risk of diabetes and ischaemic heart disease. Computed Tomography (CT) fat segmentation represents a defined method of quantifying intra-abdominal fat, with attendant radiation risks. Bioimpedance spectroscopy may offer a method of assessment without any risks to the patients. A comparison is made of these two methods.

This was a preliminary study of the utility of multifrequency bioimpedance spectroscopy of the mid abdomen as a measure of intra-abdominal fat, by comparison with fat segmentation of an abdominal CT scan in the −30 to −190 HU range.

There was a significant (P < 0.01) correlation between intra-abdominal fat and mid-upper arm circumference, as well as the bioimpedance parameter, the R/S ratio. Multivariate analysis showed that these were the only independant variables and allowed the derivation of a formula to estimate intra-abdominal fat: IAF = 0.02 × MAC − 0.757 × R/S + 0.036.

Circumabdominal bioimpedance spectroscopy may prove a useful method of assessing intra-abdominal fat, and may be suitable for use in studies to enhance other measures of body composition, such as mid-upper arm circumference.

• Bioelectrical impedance
• Bioimpedance spectroscopy
• Phase angle
• Resistance
• Wound assessment

• Hypertension
• Inflammation
• Rheumatoid arthritis
• Volume overload

• Bioimpedance
• Hemodialysis
• Impedance ratio
• Inflammation
• Mortality
• Nutrition

• Adult
• Age Factors
• Aged
• Analysis of Variance
• Cause of Death
• Cohort Studies
• Electric Impedance
• Female
• Humans
• Kaplan-Meier Estimate
• Kidney Failure, Chronic/diagnosis
• Kidney Failure, Chronic/mortality
• Kidney Failure, Chronic/therapy
• Male
• Middle Aged
• Predictive Value of Tests
• Prognosis
• Proportional Hazards Models
• Prospective Studies
• Renal Dialysis/methods
• Renal Dialysis/mortality
• Risk Assessment
• Sensitivity and Specificity
• Sex Factors
• Survival Analysis

Volume overload is the main factor responsible for the pathogenesis of hypertension in dialysis patients. Few studies have evaluated the interpretation of the parameters obtained by bioelectrical impedance (BIA) to manage these patients. The aim of this study was to assess the best cutoff level of volume overload obtained by BIA able to predict the absence of hypertension control in hemodialysis patients.

Volume overload was calculated as the difference between total body water (TBW) measured by bioimpedance and TBW estimated by the Watson formula in chronic stable hemodialysis patients. Inadequate control of blood pressure (BP) was defined as the mean of measurements obtained before five hemodialysis sessions ≥140 × 90 mm Hg. The best cutoff level of volume overload assessed by BIA able to predict the absence of BP control in patients on chronic hemodialysis was determined by the receiver operating characteristic (ROC) curve using the Youden method.

We included 205 patients, 53% male, aged 56 ± 14.5 years. The largest area under the ROC curve was found for predialysis volume overload (0.660, 95% CI 0.556-0.765, p = 0.004). The ROC curve of postdialysis volume overload also reaches statistical significance. The best cutoff point was found for predialysis volume overload ≥1.4 liters with a sensitivity of 69% and a specificity of 67%.

The association of TBW and inadequate BP control highlights the importance of volume management in hemodialysis patients. Predialysis volume overload of 1.4 liters was the parameter that best discriminated the presence of inadequate BP control.

• Bioimpedance analysis
• Blood pressure
• Extracellular volume
• Hemodialysis

• Anemia
• bioimpedance spectroscopy
• fat tissue

• extracellular volume
• hemodialysis
• segmental bioimpedance
• ultrafiltration rate
• whole body bioimpedance

Chronic fluid overload is associated with higher mortality in dialysis patients; however, the link with cardiovascular morbidity has not formally been established and may be influenced by subclinical inflammation. We hypothesized that a relationship exists between fluid overload and [i] cardiovascular laboratory parameter as well as between fluid overload and [ii] inflammatory laboratory parameters. In addition, we aimed to confirm whether volume status correlates with nutritional status.

We recorded baseline characteristics of 244 hemodialysis patients at three hemodialysis facilities in Vienna (Austria) and determined associations with volume measurements using the body composition monitor (Fresenius/Germany). In one facility comprising 126 patients, we further analyzed cardiovascular, inflammatory and nutritional parameters.

We detected predialysis fluid overload (FO) in 39% of all patients (n = 95) with FO defined as ≥15% of extracellular water (ECW). In this subgroup, the absolute FO was 4.4 +/-1.5 L or 22.9 ± 4.8% of ECW. A sub-analysis of patients from one center showed that FO was negatively associated with body mass index (r = -0.371; p = <0.001), while serum albumin was significantly lower in fluid overloaded patients (p = 0.001). FO was positively associated with D-Dimer (r = 0.316; p = 0.001), troponin T (r = 0.325; p < 0.001), and N-terminal pro-B-type natriuretic peptide (r = 0.436; p < 0.001), but not with investigated inflammatory parameters.

Fluid overload in HD patients was found to be lower in patients with high body mass index, indicating that dry weight was inadequately prescribed and/or difficult to achieve in overweight patients. The association with parameters of cardiovascular compromise and/or damage suggests that fluid overload is a biomarker for cardiovascular risk. Future studies should determine if this applies to patients prior to end-stage renal disease.

• Aged
• Body Composition
• Body Water/diagnostic imaging
• Electric Impedance
• Female
• Humans
• Lung/diagnostic imaging
• Male
• Middle Aged
• Renal Dialysis
• Ultrasonography
• Vena Cava, Inferior/diagnostic imaging