Fluid Management in Dialysis Patients

Fluid management in patients receiving dialysis is a pivotal element of care, balancing the removal of excess water and solutes against the risk of circulatory instability. In both haemodialysis and peritoneal dialysis, ultrafiltration must be tailored to achieve euvolaemia, avoiding the cardiovascular strain of hypervolaemia and the hypotension or organ ischaemia associated with over-restriction. Traditional assessments of dry weight rely on clinical signs such as blood pressure, peripheral oedema and interdialytic weight gain, but these can lack precision. Emerging approaches employ bioimpedance spectroscopy to quantify body water compartments and circulating biomarkers—most notably natriuretic peptides—to gauge intravascular volume and cardiac stress. A deeper understanding of the dynamics between extracellular and intracellular fluid has also illuminated pathways linking fluid shifts to endothelial dysfunction, inflammation and malnutrition. Collectively, these advances support an integrated model of fluid management that combines objective monitoring, personalised ultrafiltration profiling and nutritional guidance to mitigate cardiovascular risk and improve patient outcomes.

Research from Nature Portfolio

A landmark systematic review and meta-analysis of multiple cohorts demonstrated that bioimpedance-derived overhydration indices are powerful independent predictors of mortality and cardiovascular events in end-stage kidney failure. Overhydration exceeding 15% of ideal fluid volumes and decreases in phase angle—a marker of cellular integrity—were each associated with more than a twofold increase in mortality risk. This synthesis reinforces the clinical utility of whole-body bioimpedance measures as objective biomarkers for stratifying patient risk and guiding fluid removal targets.

Fluid Management in Dialysis Patients publication trend

The graph below shows the total number of articles in fluid management in dialysis patients across all publications each year (not limited to Nature Index journals).

Technical terms

Bioimpedance spectroscopy: A non-invasive technique that measures body fluid compartments by analysing electrical impedance at multiple frequencies.

Extracellular water (ECW): The volume of fluid present outside cells, including plasma and interstitial fluid.

Intracellular water (ICW): The volume of fluid contained within the cellular compartment.

Ultrafiltration: The process in dialysis by which fluid is removed across a semipermeable membrane under pressure.

Natriuretic peptides: Hormonal biomarkers released by cardiac myocytes in response to volume expansion and pressure overload.

Hypervolaemia: A state of excess fluid volume in the circulatory system and interstitial spaces.

References

1. Bioimpedance-defined overhydration predicts survival in end stage kidney failure (ESKF): systematic review and subgroup meta-analysis. Scientific Reports (2018).
2. Association between Intra- and Extra-Cellular Water Ratio Imbalance and Natriuretic Peptides in Patients Undergoing Hemodialysis. Nutrients (2023).
3. Inflammation in Hypervolemic Hemodialysis Patients: The Roles of RelB and Caspase-4. International Journal of Molecular Sciences (2023).
4. Ratio of Extracellular to Intracellular Water Is Associated with Permanent Catheter Patency Survival in Patients Receiving Maintenance Hemodialysis. Diagnostics (2023).