Bioimpedance Spectroscopy (BIS): Fluid Changes in Hemodialysis Patients

NCT07803029 | Recruiting

• 1 other identifier: VMK2500694
• Study Type: interventional
• Target: 42
• Locations: 1 country
• Sites: 1

Brief Summary

In connection with dialysis treatment, fluid and salt balance changes. Some kidney disease patients experience fluid accumulation in the body and need to have excess fluid removed via the dialysis machine. Others have too little fluid in their bodies and experience general symptoms. The amount of fluid that needs to be removed is an individual assessment and can be difficult to determine. Today, fluid removal is determined based on signs such as water in the lungs, swollen legs, and blood pressure. By using a so-called bioimpedance spectroscopy (BIS) device, it os possible measure how much fluid is in the body. However, the calculations that BIS devices use are developed for healthy individuals and do not work optimally during dialysis. Therefore, the investigators will use the actual measurements and compare them with fluid extraction and weight changes to examine their relationship. Hemodialysis patients with ultrafiltration on 3 consecutive dialysis days in order to investigate whether there is a difference in measurements after the long dialysis break and whether the measurements are the same when you are being drawn to your dry weight are included. Other patients without fluid removed during dialysis will be investigated once. I the study the absolute blood volume is also measured, that is, how much fluid is in the bloodstream. This is also an expression of the body's total fluid volume. By combining the various measurements, the study will gain increased knowledge about your hydration status. If the measurement methods have sufficient precision, the use of BIS and measurement of total blood volume may contribute to a more accurate determination of your dry weight.

Conditions

Hemodialysis

Keywords

hemodialysis; bioimpedance; absolute blood volume; total body water; extracellular body water; intracellular water; body weight

Outcome Measures

Primary Outcomes (1)

• Changes in BIS measured resistance and fluid removed

  To investigate whether raw impedance data from BIS measurements can be used as a tool to estimate changes in fluid status in HD patients before and after a hemodialysis session of 4 hours duration. Weight loss during a hemodialysis session is equivalent to fluid removed. The meausement are don for up to oen week 1. To determine consistency in measurements of raw impedance data (Ω) between different BIS devices (here: Fresenius BCM ®, SFB7 ® and SOZO ® from Imped-iMed). 2. Change in raw impedance data (Ω) during a hemodialysis session of 4 hours 3. Degree of ultrafiltrating (ml) a hemodialysis session of 4 hours 4. Change in absolute blood volume (ml) during a hemodialysis session of 4 hours 4\) In a subset of patients test if the length of the of pause (days) between hemodialysis session influence the raw impedance measurements.

  From enrollment to the end of the dialysis session

Study Arms (1)

Hemodialysis patient

ACTIVE COMPARATOR

Measurement wil be donne before and after a hemodialysis. Bioimpendance spectroscopy is measured with 3 different bioimpedance apperatur. Absolute blood volumen is measured 5-10 minutes after starting and before stopping the dialysis session. For center hemodialysis patients with ultrafiltration measurement til be performed on 3 consecutive days and for patient center hemodialysis patient meaurement wil be performed once with also apply for Home hemodialysis patients.

Device: Bioimpedance analysis

Interventions

Bioimpedance analysis DEVICE

Comparing the perfomance of original data from 3 different bioimpedance apparatur and test there precision and accurary compared to ultrafiltration. And whether the performance of measuring absolut blood volume is better

Hemodialysis patient

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Hemodialysis for more than 3 month Hemodynamic stabile during a dialysis session

You may not qualify if:

• Amputated limbs.
• Pregnant.
• Extremity palsy and paralysis.
• Implanted electronic device (e.g., pacemaker or ICD).
• Regular use of dialysate sodium proliferation.
• Hip, knee and shoulder prosthesis.
• Dialysis fistula in both arms.
• Inability to give informed consent.
• History of discontinuation of dialysis treatment prematurely.

Sponsors & Collaborators

• Per Ivarsen: lead

Study Sites (1)

Aarhus University Hospital

Aarhus, Central Denmark, 8200, Denmark

RECRUITING

MeSH Terms

Conditions

Body Weight

Condition Hierarchy (Ancestors)

Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Central Study Contacts

Per Ivarsen, MD

CONTACT

+457845000; per.ivarsen@clin.au.dk

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: OTHER
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Clinical Professor

Study Record Dates

• First Submitted: August 3, 2026
• First Posted: September 3, 2026
• Study Start: May 11, 2025
• Primary Completion (Estimated): October 16, 2026
• Study Completion (Estimated): December 31, 2026
• Last Updated: September 3, 2026

Record last verified: 2026-05

Locations

DK (1)