Cool temperature hemodialysis and biocompatibility in chronic hemodialysis patients: a preliminary study

Background: Cooler temperature dialysate (TD) has gained in popularity in the treatment of hypotension during hemodialysis (HD). In this study we verified the hypothesis of an eventual involvement of cytokines. Methods: Four patients on regular HD underwent two 4-hour HD sessions once at 37 C TD and once at 35 degrees C TD. The concentration of the cytokines (cyt) IL-1, IL-2, IL-8, IL-12 and tumor necrosis factor-alpha (TNF-alpha) was measured before the HD session initiation and after 20, 60, 120 and 240 minutes. Body temperature, weight, blood pressure and heart rate were registered at the same time points. Results: We found a higher blood pressure at 35 C but no intradialytic differences in cyt concentration at 35 C or 37 C. The percentage changes of cyt from baseline were very slight, except for IL-8 which decreased by 40% both at 35 C and 37 degrees C. Conclusions: These preliminary results suggest that cytokines do not seem play a relevant role in determining the favorable effects of cooler TD on blood pressure. Our study is preliminary and our results need to be confirmed by other studies.