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Examining the Impact of Using Two Dialysers in Parallel on Dialysis Adequacy in Hemodialysis Patients

This study has been completed.
University of Calgary
Information provided by (Responsible Party):
Marcello Tonelli, University of Alberta Identifier:
First received: February 3, 2012
Last updated: December 7, 2016
Last verified: December 2016
The purpose of this study is to investigate the effectiveness of using two dialysers to lower the blood mineral levels in people receiving hemodialysis as compared to using one dialyser (usual treatment).

Condition Intervention
End Stage Renal Disease Procedure: Single dialyzer Procedure: Two dialyzers

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Examining the Impact of Using Two Dialysers in Parallel on Dialysis Adequacy in Hemodialysis Patients

Resource links provided by NLM:

Further study details as provided by Marcello Tonelli, University of Alberta:

Primary Outcome Measures:
  • Dialysate clearance of phosphate [ Time Frame: 3 weeks ]
    Dialysate phosphate clearance levels in double dialyzer periods compared to single dialyzer periods.

Secondary Outcome Measures:
  • Serum phosphate [ Time Frame: 3 weeks ]
    Serum phosphate levels in the double dialyzer periods compared to the single dialyzer periods.

  • Dialysate removal of phosphate [ Time Frame: 3 weeks ]
    Dialysate removal levels of phosphate in the double dialyzer periods compared to the single dialyzer periods.

Other Outcome Measures:
  • Proportion of participants with serious adverse events [ Time Frame: 30 days following last day of intervention ]
    The proportion of participants during the double dialyzer period compared to the single dialyzer period experiencing serious adverse events resulting in death, life threatening illness, hospitalization or prolongation of existing hospitalization, or persistent or significant disability.

  • Proportion of participants with adverse events [ Time Frame: 30 days following last day of intervention ]
    The proportion of participants with adverse events (and by each type of adverse event) during the double dialyzer intervention compared to single dialyzer intervention.

Enrollment: 33
Study Start Date: January 2013
Study Completion Date: December 2014
Primary Completion Date: November 2014 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Single dialyzer
Single dialyzer
Procedure: Single dialyzer
Hemodialysis treatment using a single Baxter dialyzer - considered standard hemodialysis treatment.
Experimental: Double dialyzer
Two dialyzers in parallel
Procedure: Two dialyzers
Hemodialysis treatment using a two Baxter dialyzers in parallel.

Detailed Description:

Higher levels of serum phosphate are independently associated with an increased risk of death in hemodialysis patients. Therefore, there has been considerable interest in controlling serum phosphate while minimizing oral calcium load. While most attention has focused on the use of non-calcium containing phosphate binders such as sevelamer and lanthanum, modifying conventional dialysis regimens to improve phosphate clearance is an alternative approach that remains relatively unstudied. A secondary analysis of a previous randomized cross-over study from our group found that the use of two dialysers in parallel resulted in a reduction in pre-dialysis serum phosphate levels. As this study was small, and the mechanisms resulting in the reduction in phosphate levels were unclear, further study is warranted. The investigators will conduct a randomized cross-over study comparing the impact of dialyzing using two dialysers in parallel with a single dialyser in hyperphosphatemic hemodialysis patients.

There will be a total of 34 participants from Alberta,Canada participating in this study. The length of study participation is 10 weeks.


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

Inclusion Criteria:

  • Age > 18 years
  • Patients must be on a stable regimen of hemodialysis for ≥ 3 months ('stable' defined as not expected to require a change to the duration or frequency of treatments)
  • Serum phosphate > 1.6 mmol/l on last two consecutive lab tests at least 3 weeks apart (KDOQI guidelines recommend maintaining predialysis phosphate < 1.8mmol/l - as such, phosphate lowering in this subgroup of patients is particularly relevant)
  • Patients must be on stable doses of a phosphate binder with no changes in dose 1 month prior to study enrolment.
  • Blood flow rate ≥ 350 ml/min through a well-functioning access (This will exclude patients receiving inadequate dialysis due to a temporary venous dialysis catheter and will ensure sufficient blood flow to permit dialysis using two dialysers in parallel.)

Exclusion Criteria:

  • Patients who have a scheduled renal transplant, change in dialysis modality, surgery or hospitalization or plan on moving away from the study site in the next three months.
  • Patients with a projected life expectancy of less than 3 months.
  • Patients with a contraindication to intra-dialytic anticoagulation. (Some patients require a small increase in the amount of anticoagulation required to prevent dialyser clotting when using two dialysers in parallel).
  • Patients who have missed >8 dialysis treatments in the past 3 months.
  • Patients with a dialysis regimen of >3 runs per week.
  • Failure to provide informed consent.
  • Patients enrolled in another (interventional) trial
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01539252

Canada, Alberta
University of Calgary
Calgary, Alberta, Canada, T2N 2T9
University of Alberta
Edmonton, Alberta, Canada, T6G 2V2
Sponsors and Collaborators
University of Alberta
University of Calgary
Principal Investigator: Marcello Tonelli, MD University of Alberta
Principal Investigator: Braden Manns, MD University of Calgary
  More Information

Additional Information:
Responsible Party: Marcello Tonelli, Principal Investigator, University of Alberta Identifier: NCT01539252     History of Changes
Other Study ID Numbers: DDphos1
Study First Received: February 3, 2012
Last Updated: December 7, 2016
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

Keywords provided by Marcello Tonelli, University of Alberta:
phosphate clearance
double dialyzer
two dialyzers in parallel

Additional relevant MeSH terms:
Kidney Failure, Chronic
Renal Insufficiency, Chronic
Renal Insufficiency
Kidney Diseases
Urologic Diseases processed this record on September 21, 2017