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

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).

Study Overview

• Status: Completed
• Conditions: End Stage Renal Disease
• Intervention / Treatment: Procedure: Single dialyzer; Procedure: Two dialyzers

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.

• Study Type: Interventional
• Enrollment (Actual): 33
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Alberta
    • Calgary, Alberta, Canada, T2N 2T9
      • University of Calgary
    • Edmonton, Alberta, Canada, T6G 2V2
      • University of Alberta

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: 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.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Dialysate clearance of phosphate	Dialysate phosphate clearance levels in double dialyzer periods compared to single dialyzer periods.	3 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Serum phosphate	Serum phosphate levels in the double dialyzer periods compared to the single dialyzer periods.	3 weeks
Dialysate removal of phosphate	Dialysate removal levels of phosphate in the double dialyzer periods compared to the single dialyzer periods.	3 weeks

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of participants with serious adverse events	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.	30 days following last day of intervention
Proportion of participants with adverse events	The proportion of participants with adverse events (and by each type of adverse event) during the double dialyzer intervention compared to single dialyzer intervention.	30 days following last day of intervention

Collaborators and Investigators

• Sponsor: University of Alberta
• Collaborators: University of Calgary
• Investigators: Principal Investigator: Marcello Tonelli, MD, University of Alberta; Principal Investigator: Braden Manns, MD, University of Calgary

Publications and helpful links

General Publications

• Thompson S, Manns B, Lloyd A, Hemmelgarn B, MacRae J, Klarenbach S, Unsworth L, Courtney M, Tonelli M. Impact of using two dialyzers in parallel on phosphate clearance in hemodialysis patients: a randomized trial. Nephrol Dial Transplant. 2017 May 1;32(5):855-861. doi: 10.1093/ndt/gfw085.

Helpful Links

• Open access publication

Study record dates

Study Major Dates

• Study Start: January 1, 2013
• Primary Completion (Actual): November 1, 2014
• Study Completion (Actual): December 1, 2014

Study Registration Dates

• First Submitted: February 3, 2012
• First Submitted That Met QC Criteria: February 21, 2012
• First Posted (Estimate): February 27, 2012

Study Record Updates

• Last Update Posted (Estimate): December 8, 2016
• Last Update Submitted That Met QC Criteria: December 7, 2016
• Last Verified: December 1, 2016

More Information

Terms related to this study

• Keywords: hemodialysis; adequacy; phosphate clearance; double dialyzer; two dialyzers in parallel
• Additional Relevant MeSH Terms: Kidney Diseases; Urologic Diseases; Renal Insufficiency; Renal Insufficiency, Chronic; Kidney Failure, Chronic
• Other Study ID Numbers: DDphos1

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No