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Uremic Toxin Removal and Hemodynamics in Long-hour Hemodialysis and Hemodiafiltration

This study has been completed.
Information provided by (Responsible Party):
Maastricht University Medical Center Identifier:
First received: March 16, 2011
Last updated: June 12, 2013
Last verified: June 2013

Rationale: The mortality of end-stage renal disease (ESRD) patients on dialysis remains high. This may at least be partly due to the insufficient removal of (especially protein-bound) uremic toxins which have been associated with cardiovascular morbidity and mortality. It is unknown whether the combination of long-hour haemodialysis (HD) with convection increases the removal of these toxins. Long-hour HD and long-hour haemodiafiltration (HDF) may also improve haemodynamic stability which is an important factor in treatment quality. The investigators aim to study the removal of uremic toxins in long-hour HD and HDF and to compare the haemodynamics between 4-hour and 8-hour HD and HDF.

Objectives: The primary aim is to study the removal of (especially protein-bound) uremic toxins in 4-hour and 8-hour HD and HDF. A secondary aim is to compare the haemodynamic response between 4-hour and 8-hour HD and HDF.

Condition Intervention
Uremic Toxins
Haemodynamic Stability
Other: 4-hour HD, 4-hour HDF, 8-hour HD and 8-hour HDF

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Uremic Toxin Removal and Hemodynamics in Long-hour Hemodialysis and Hemodiafiltration; a Randomized Cross-over Study

Resource links provided by NLM:

Further study details as provided by Maastricht University Medical Center:

Primary Outcome Measures:
  • removal of uremic toxins [ Time Frame: before dialysis and at 15,30,60,120,240 minutes (4-hour and 8-hour sessions) and at 360 and 480 minutes (8-hour sessions) ]
    To measure uremic toxin and electrolyte removal, reduction ratios, dialytic clearances and mass removal in collected dialysate will be determined. Blood samples will be taken from the inlet blood lines immediately before the onset of dialysis and at 15, 30, 60, 120, 240 minutes (4-hour and 8-hour sessions) and at 360 and 480 minutes (8-hour sessions). Furthermore, ultrafiltrate and dialysate will be continuously collected in a fractionated way.

Secondary Outcome Measures:
  • haemodynamic response [ Time Frame: every 30 minutes until end of dialysis ]
    BP, heart rate, heart rate variability, cardiac output and systemic vascular resistance will be measured every 30 minutes by the Task Force Monitor. Skin microcirculation will be measured with laser Doppler flowmetry every 120 min until the end of the treatment.

Enrollment: 20
Study Start Date: October 2011
Study Completion Date: June 2013
Primary Completion Date: January 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
hemodialysis patients
conventional hemodialysis patients
Other: 4-hour HD, 4-hour HDF, 8-hour HD and 8-hour HDF
Prevalent conventional HD (CHD) patients (dialysing 3 days a week during 4 hours per dialysis session) will undergo, in random order, a mid-week 4-hour HD session, a mid-week 4-hour HDF session, a mid-week 8-hour HD session, and a mid-week 8-hour HDF session with a 2-week interval between every session to assess the influence of treatment duration and of convection on the removal of uremic toxins and on the haemodynamic responses and autonomic nervous regulation. In between the study dialysis sessions these patients will receive routine CHD treatments.


Ages Eligible for Study:   18 Years to 80 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • prevalent conventional HD patients
  • AV-fistula enabling double-needle vascular access with blood flow rate of at least 350 ml/min
  • informed consent
  • age more than 18 years

Exclusion Criteria:

  • withdrawal of consent
  • acute intercurrent illness (infection, malignancy, cardiovascular event, uncontrolled diabetes)
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Please refer to this study by its identifier: NCT01328119

Maastricht University Medical Center
Maastricht, Limburg, Netherlands, 5800
Sponsors and Collaborators
Maastricht University Medical Center
  More Information

Responsible Party: Maastricht University Medical Center Identifier: NCT01328119     History of Changes
Other Study ID Numbers: NL34908.068.10
Study First Received: March 16, 2011
Last Updated: June 12, 2013 processed this record on May 25, 2017