title: Effect of cool vs. warm dialysate on toxin removal: rationale and study design.
abstract: BACKGROUND
  Cool dialysate is often recommended for prevention of intra-dialytic hypotensive episodes in maintenance hemodialysis (HD) patients. However, its effect on toxin removal is not studied. It is known that inter-compartmental resistance is the main barrier for toxin removal. Cool dialysate can potentially increase this resistance by vasoconstriction and thus impair the toxin removal. The aim of this trial is to compare the toxin removal outcome associated with cool vs. warm dialysate.
  
  
  METHODS
  This study is based on the hypothesis that dialysate temperature, a potential maneuver to maintain hemodynamic stability during HD, may influence inter-compartmental resistance and hence, toxin removal. Only stable HD patients will be recruited for this study. The quantum of removed toxins will be assessed by the total spent dialysate, which is a gold standard to quantify the efficacy of a single dialysis session. Collected samples will be analyzed for urea, creatinine, phosphate, β2-microglobulin, and uric acid. The study is a single center, self-controlled, randomized prospective clinical research where 20 study subjects will undergo 2 dialysis sessions: (a) cool dialysis with dialysate at 35.5°C, and (b) warm dialysis with dialysate at 37°C. Pre- and post-dialysis blood samples will be collected to quantify the dialysis adequacy and toxin reduction ratio.
  
  
  CONCLUSIONS
  This is the first clinical research to investigate the effect of dialysate temperature on removal of both small and large-sized toxins. Successful completion of this research will provide important knowledge pertaining to dialysate temperature prescription. Results can also lead to the hypothesis that cool dialysate may help in by preventing intra-dialytic hypotensive episodes, but prolonged prescription of cool dialysate may lead to comorbidities associated with excess toxin accumulation. The new knowledge will encourage for personalized dialysate temperature profiling.
  
  
  BACKGROUND
  Clinicaltrials.gov Identifier--NCT02064153.
authors.affiliation: National University of Singapore, 21 Lower Kent Ridge Road, Singapore, 119077, Singapore. vmaheshwari@u.nus.edu.|Current Affiliation: Renal Research Institute, 315 East 62nd Street 4th Floor, New York, NY, 10065, USA. vmaheshwari@u.nus.edu.
authors.forename: Vaibhav
authors.initials: V
authors.lastname: Maheshwari
authors.affiliation: Division of Nephrology, Department of Medicine, National University Health System, 1E Kent Ridge Road, Singapore, 119228, Singapore. titus_lau@nuhs.edu.sg.
authors.forename: Titus
authors.initials: T
authors.lastname: Lau
authors.affiliation: Department of Chemical and Biomolecular Engineering, National University of Singapore, 21 Lower Kent Ridge Road, Singapore, 119077, Singapore. chels@nus.edu.sg.
authors.forename: Lakshminarayanan
authors.initials: L
authors.lastname: Samavedham
authors.affiliation: Department of Chemical and Biomolecular Engineering, National University of Singapore, 21 Lower Kent Ridge Road, Singapore, 119077, Singapore. chegpr@nus.edu.sg.
authors.forename: Gade P
authors.initials: GP
authors.lastname: Rangaiah
mesh_terms: D000328:Adult; D000368:Aged; D003080:Cold Temperature; D005260:Female; D005500:Follow-Up Studies; D015312:Hemodialysis Solutions / Q000627:therapeutic use*; D006358:Hot Temperature / Q000627:therapeutic use*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000175:diagnosis / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D006435:Renal Dialysis / Q000379:methods*; D018570:Risk Assessment; D014118:Toxins, Biological / Q000097:blood*; D016896:Treatment Outcome
chemical_list: D015312:Hemodialysis Solutions; D014118:Toxins, Biological