Grand Rounds April 21, 2023: Personalised Cooler Dialysate for Patients Receiving Maintenance Haemodialysis (MyTEMP): A Pragmatic, Cluster-randomised Trial (Amit Garg, MD, MA, FRCPC, FACP, PhD; Stephanie N. Dixon, PhD MSc)

Posted on by Elizabeth Mccamic

Speakers

Amit Garg, MD, MA (Education) FRCPC, FACP, PhD
Associate Dean, Clinical Research, Schulich School of Medicine and Dentistry
Lead, Institute for Clinical Evaluative Sciences Kidney, Dialysis and Transplantation Provincial Program
Director, Institute for Clinical Evaluative Sciences (ICES) Western Facility
Nephrologist, London Health Sciences Centre
Professor, Medicine, Epidemiology & Biostatistics, Western University

Stephanie N. Dixon, PhD MSc
Staff Scientist, Institute for Clinical Evaluative Sciences Kidney, Dialysis and Transplantation Research Program
Biostatistician, London Health Sciences Centre

 

Keywords

MyTEMP, Pragmatic Clinical Trials, Ethics, Biostatistics

 

Key Points

  • For each hemodialysis treatment clinicians typically set the temperature of dialysate on the machine to 36.5 or 37.0 degrees Celsius. The reasoning for this temperature is unclear, though it likely represents what was considered the average body temperature of most patients.
  • In a recent international survey of more than 270 centers, nearly half now use a cooler temperature dialysate in patient care of less than or equal to 36.0 degrees C. This change in practice is based on data that suggests the at cooler (vs. standard) temperature dialysate is beneficial. However, in two recent systematic reviews the overall quality of evidence for dialysate cooling was deemed low with a high risk of bias.
  • The MyTEMP trial is a pragmatic, cluster randomized controlled trial in Ontario, Canada, to determine if adopting a default center-wide policy of personalized cooler dialysate is superior to a standard temperature dialysate of 36.5 degrees C.
  • MyTEMP was innovative and pragmatic, implemented as part of a learning healthcare system, with covariate constrained randomization, registry-based, and embedded in routine care delivered by more than 2,000 nurses at 84 centers.
  • During the 4-year study period, about 8,000 patients were randomized for the personalized cooler dialysate and about 7,400 were randomized for the standard temperature dialysate. The mean temperature for the standard group was 36.4 degrees C, and the mean temperature for cooler group was 35.8 degrees C.
  • The primary composite outcome was cardiovascular mortality or hospital admission with MI, stroke, or heart failure. There is a high risk of these events in the hemodialysis population with a cumulative instance at 30% at 4 years. There was no appreciable difference in the estimate for the cooler temperature group. Additionally, the cooler temperature group reported a higher likelihood of discomfort.
  • The lack of cardiovascular benefit and higher likelihood of patient discomfort provides no justification to adopt cooler dialysate as a center-wide policy vs. use of 36.5 degrees. After MyTEMP, centers in Ontario stopped adopting colder temperature dialysate as a center-wide policy, and patients felt less discomfort during hemodialysis care.
  • Cluster randomized trials of hemodialysis center-wide policies raise complex ethical issues. Many patients who receive hemodialysis are vulnerable. A patient or their nephrologist could decide to opt-out of the randomly allocated center-wide default policy but could not opt out of the symptom data but not de-identified health records. The REB approved the MyTEMP request to use an altered patient consent process because the research was deemed of minimal risk to patients.
  • MyTEMP worked with patients and caregivers to develop the trial, and Kidney Patient and Family Advisory Councils guided the choice of additional outcomes. Participants were debriefed on the trial results.

Learn more

Read about the MyTEMP trial in The Lancet.

Read about the MyTEMP statistical analysis plan.

Discussion Themes

–We run into situations where we are talking to stakeholders and thinking about criteria for waiver of consent and it’s just not right. Where the risks and benefits are equal, but I wouldn’t want to be randomly assigned. There is a natural assertion of autonomy. Did some of these questions of autonomy vs. risk come up? I think it is very complex, and it is not black and white. You need to identify the principles before the process. In terms of the dialysis component, in routine care we get consent when we start treatment but there are many things in the background. As a clinician when I am providing care, I’m not discussing these concerns; we are talking about other things. Am I delivering great medicine when I’m not sure what to do here when there is practice variability?

Tags

#pctGR, @Collaboratory1