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Abstract: PO0877

Impact of Hydration Status Measurement by Bioimpedance Analysis (BIA) on Haemodialysis Patients

Session Information

Category: Dialysis

  • 701 Dialysis: Hemodialysis and Frequent Dialysis


  • Samad, Nasreen, Barts Health NHS Trust, London, London, United Kingdom
  • Ave, Franel, Barts Health NHS Trust, London, London, United Kingdom
  • Khan, Sara Z., American University of Antigua College of Medicine, Saint Johns, Antigua and Barbuda
  • Lalu, Jerilyn, Barts Health NHS Trust, London, London, United Kingdom

Volume status in haemodialysis patients is an important prognostic factor. Overhydration is associated with a higher frequency of mortality while dialysis-induced volume depletion is also an independent mortality risk factor. Clinical indices do not always accurately reflect volume status. Bioimpedance analysis (BIA) is used as a simple, noninvasive method which can measure normovolumic status in haemodialysis patients by measurement of height, weight, and body composition. Fluid overload is calculated by subtracting the normovolumic status from the overhydration status.


All patients at Queens satellite dialysis unit, Romford, United Kingdom, which has a prevalent population of 106 patients had BIA based assessment of fluid status every 3 months from July 2020 to May 2021 and dry weight adjusted accordingly.Outcomes were noted for blood pressure, overhydration, Interdialytic weight gains, intradialytic hypotension, hospitalisation and mortality.


121 haemodialysis patients were followed with male to female ratio of 55:66, mean age of 62 (25-87) of whom 46 were diabetics. By end of assessment period, 21 patients had died (13 due to COVID related illness). In July 2020, 31 patients had overhydration of 2 litres or more, which reduced to 20 patients, in May 2021.
The number of patients who had underhydration of -1 litre or more remained similar with 12 patients in July 2020 compared to 11 in May 2021 in spite of more aggressive approach to reduction in dry weight.
The dialysis population had high turnover due to deaths as well and 2 transplantations and 2 transfers out of the unit. During the time of study 15 patients were admitted to hospital with features of fluid overload.


Bioimpedence analysis (BIA) is a simple, non invasive tool helpful in assessing fluid status in haemodialysis patients. It is easier to convince a patient about their volume status by providing a machine assessed figure rather than clinical parameters. There was significant improvement in overhydration without increasing the number of dehydrated patients. The high mortality in prevalent patients during COVID pandemic highlights the need for continued body composition measurements in a larger population once COVID cases subside to come to a significant conclusion about the impact of BIA in improving patient outcomes including effect on residual renal function.