Can Bioimpedance Analysis Be Used to Estimate Absolute Blood Volume in Hemodialysis Patients?

Introduction: Under physiological conditions, blood volume and extracellular volume are in a ratio of 1-3, even in hemodialysis patients. The question therefore arises: can blood volume be inferred from the bioimpedance analysis data? The aim of the study was to compare the blood volumes calculated from extracellular volume determined by bioimpedance analysis data to the actually measured blood volumes.

Methods: Immediately before treatment, extracellular volume and volume overload were evaluated by bioimpedance spectroscopy.

Absolute blood volume and long-term survival in chronic hemodialysis patients.

Current online hemodiafiltration devices can be used to determine the absolute blood volume in clinical practice using the dialysate bolus method. Most of publications on this method have focused on preventing intradialytic complications. The influence of absolute blood volume on long-term prognosis has not been reported yet.

Vascular refilling in hemodialysis using feedback-controlled ultrafiltration profile.

Background: The rate and the duration of ultrafiltration (UF) are considered the most important factors to affect vascular refilling. The aim of the study was to investigate whether a UF profile could improve the vascular refilling.

Methods: Dialysis was delivered by a machine providing feedback control of ultrafiltration rates.

Estimation of Absolute Blood Volume Using Online Dialysate Dilution: When and How to Measure?

Absolute blood volume can be calculated from the increase in relative blood volume after an infusion of a well-defined volume bolus of ultrapure dialysate into the extracorporeal circulation. Several working groups have applied this method in research and clinical practice. A critical analysis of differing blood volume data between working groups revealed methodologic problems of the measurement procedure and some important technical aspects.

Plasma NGAL levels in stable kidney transplant recipients and the risk of allograft loss.

Background: The objective of this study was to investigate the utility of neutrophil gelatinase-associated lipocalin (NGAL) and calprotectin (CPT) to predict long-term graft survival in stable kidney transplant recipients (KTR).

Methods: A total of 709 stable outpatient KTR were enrolled >2 months post-transplant. The utility of plasma and urinary NGAL (pNGAL, uNGAL) and plasma and urinary CPT at enrollment to predict death-censored graft loss was evaluated during a 58-month follow-up.

Vascular refilling depends on the ratio of blood volume to extracellular volume in hemodialysis patients.

The ratio of blood volume to extracellular volume is approximately one to three under physiological conditions and also in stable chronic hemodialysis patients. Recently, it was found that this ratio remains unchanged during hemodialysis despite ultrafiltration. This would signify that the higher the ratio, the lower the refilling and vice versa.

Dynamics of vascular refilling in extended nocturnal hemodialysis.

Introduction: Long dialysis treatments are generally assumed to mitigate the ultrafiltration (UF) induced volume perturbation and to improve vascular refilling because of reduced UF rates and sufficient time for volume re-equilibration. The time course of vascular refilling was therefore examined during extended nocturnal dialysis.

Methods: For each hour of dialysis, vascular refilling volume was calculated from the absolute blood volume changes and UF volume removed.

CytoSorb Rescue for COVID-19 Patients With Vasoplegic Shock and Multiple Organ Failure: A Prospective, Open-Label, Randomized Controlled Pilot Study.

Objectives: To investigate the effect of extracorporeal cytokine reduction by CytoSorb (CytoSorbents, Monmouth Junction, NJ) on COVID-19-associated vasoplegic shock.

Design: Prospective, randomized controlled pilot study.

Setting: Eight ICUs at three sites of the tertiary-care university hospital Charité-Universitätsmedizin Berlin.

An improved method to estimate absolute blood volume based on dialysate dilution.

Online hemodiafiltration machines equipped with a blood volume monitor and the possibility to rapidly infuse exact amounts of ultrapure dialysate into the extracorporeal circulation can be used to determine absolute blood volume in clinical practice. The aim of the present study was to evaluate the reproducibility of such measurements. Intra-individual reproducibility was evaluated in four measurements taken in hourly intervals within the same dialysis treatment.

Inosine 5'-Monophosphate Dehydrogenase Activity for the Longitudinal Monitoring of Mycophenolic Acid Treatment in Kidney Allograft Recipients.

Background: Mycophenolic acid (MPA) is a standard immunosuppressant in organ transplantation. A simple monitoring biomarker for MPA treatment has not been established so far. Here, we describe inosine 5'-monophosphate dehydrogenase (IMPDH) monitoring in erythrocytes and its application to kidney allograft recipients.

Feedback control of absolute blood volume: A new technical approach in hemodialysis.

Introduction: The success of automatic feedback control systems to improve hemodynamic stability by preventing relative blood volume from dropping beyond a critical value during dialysis is limited. The aim of this study was to use one of these systems for control of absolute rather than relative blood volume to prevent volume-dependent morbid events.

Methods: Dialysis was delivered by a machine providing feedback control of ultrafiltration rates, relative blood volume monitoring, and accurate bolus infusion of 240 mL of dialysate to measure absolute blood volume at the beginning of dialysis.

Adjustment of target weight based on absolute blood volume reduces the frequency of intradialytic morbid events.

Introduction: Adequate volume management removing excess volume and at the same time avoiding intradialytic morbid events (IME) remains a core problem in current hemodialysis (HD) therapy. Recently, we developed a feasible method to determine absolute blood volume (Vs, in mL/kg) in patients on HD. The aim of this study was to investigate the suitability of Vs measurements for volume management.

Vascular Refilling Is Not Reduced in Dialysis Sessions with Morbid Events.

Background: It is commonly believed that insufficient vascular refilling leads to hypovolemia during hemodialysis and contributes to intradialytic morbid events (IME). But data of refilling volumes at the time of IME are lacking.

Methods: We compared the vascular refilling in 10 patients with IME with 14 stable patients with normal blood volume at the dialysis end (66-80 mL/kg).

Comorbidities, Hospitalization, and Living Status of Dialysis Patients Over 80 Years.

Background: An increasing number of patients start dialysis when they are over 80 years or reaches their eighties on dialysis. The burden of dialysis can affect their quality of life.

Methods: Clinical and social data of all patients aged 80 years or older who underwent chronic dialysis treatment in a single center were analyzed.

Vascular refilling is independent of volume overload in hemodialysis with moderate ultrafiltration requirements.

Introduction Blood volume changes and vascular refilling during hemodialysis (HD) and ultrafiltration (UF) have been assumed to depend on volume overload (Vo ). It was the aim to study the magnitude of vascular refilling in stable HD patients with moderate volume expansion in everyday dialysis using novel technical approaches. Methods Patients were studied during routine dialysis and UF based on clinical dry weight assessment.

Effects of Osmotic Changes on Measuring Relative Blood Volume: Comparison of Three Hemodialysis Devices.

Recording the relative blood volume is a standard feature of modern dialysis devices. Three different measurement systems are incorporated in currently available dialysis machines. The Gambro-Hospal group and Nikkiso feature blood volume monitors based on different optical methods.

Determination of the critical absolute blood volume for intradialytic morbid events.

The reduction of blood volume below a critical threshold is assumed to trigger intradialytic morbid events (IME). Recently, we presented a simple method to determine the absolute blood volume during routine hemodialysis (HD) carried out without blood sampling and without injection of dyes or radiolabeled markers. Such information could be used to detect excessive volume reduction during HD and to prevent IME.

Relative Blood Volume Monitoring during Renal Replacement Therapy in Critically Ill Patients with Septic Shock: A Preliminary Report.

Background: Volume management during renal replacement therapy (RRT) in septic shock is always in the conflict between aggravating hypovolemia by undue ultrafiltration (UF) and insufficient reduction of fluid overload which is associated with adverse outcome. Relative blood volume (RBV) monitoring could be helpful for timely transition from fluid resuscitation to fluid removal.

Methods: Data of RBV were continuously monitored and used for guidance of UF and fluid resuscitation in 21 consecutive patients with severe septic multiple organ failure.

Hemodialysis in patients over 80 years.

Background: In Germany, every fifth patient starting dialysis is now 80 years of age or older. The question that is currently relevant is not whether we have to treat patients who are older than 80. Rather the question now is how to treat this elderly group of patients.

A simple and feasible method to determine absolute blood volume in hemodialysis patients in clinical practice.

Background: We developed a simple method to determine the absolute blood volume (V) during hemodialysis in everyday clinical practice and examined its relationship with volume overload, clinical relevance, and accuracy.

Methods: The increase in relative blood volume (RBVpost - RBVpre) measured before and after infusion of 240 ml of ultra-pure dialysate using the bolus function of a commercial online hemodiafiltration machine incorporating a relative blood volume monitor was applied to determine absolute blood volume. The specific blood volume (Vs, blood volume per kg body mass at dry weight, in ml/kg) was compared to volume status as assessed by bioimpedance analysis and clinical criteria.

Effects of sodium on measuring relative blood volume during hemodialysis differ by techniques.

Recording the relative blood volume is a standard feature of modern dialysis devices, enabling feedback guidance of ultrafiltration and dialysate conductivity. Technically, the process is based on optical or ultrasonic methods. On the grounds of clinical evidence suggesting a malfunction of the optical hemoglobin (Hb)-dependent absorbance method in the presence of sodium changes, we compared the system with the ultrasonic method.

Extended daily on-line high-volume haemodiafiltration in septic multiple organ failure: a well-tolerated and feasible procedure.

Background: The outcome of patients with septic multiple organ failure (MOF) remains poor. There are experimental and clinical data indicating a beneficial effect of high-volume haemofiltration. Delivering high-volume therapy is only cost effective using on-line devices because of high costs for additional solution bags in conventional continuous renal replacement therapy (CRRT).

Rosuvastatin is additive to high-dose candesartan in slowing progression of experimental mesangioproliferative glomerulosclerosis.

Rosuvastatin is additive to high-dose candesartan in slowing progression of experimental mesangioproliferative glomerulosclerosis (GS). Progressive mesangioproliferative glomerulonephritis, mostly IgA nephropathy, is a major cause of end-stage kidney disease worldwide. In a chronic-progressive model of mesangioproliferative GS, we tested the renoprotective efficacy of rosuvastatin alone and in combination with a high-dose of the AT(1) blocker candesartan.