The Effect of Dialysate Temperature on Dialysis Adequacy and Hemodynamic Stability: An Experimental Study with Crossover Design.

Abstract

Cool dialysate has variable impact on hemodynamic stability and dialysis adequacy. Hemodynamic stability and dialysis adequacy are crucial indicators for better life expectancy and cardiovascular mortality. This research aims to evaluate the impact of cool dialysate temperature (35.5°C) compared to standard dialysate temperature (37°C) on blood pressures, pulse rate, and dialysis adequacy (Urea reduction ratio and online Kt/V) in a cross over design. Material and Methods. Consenting ESRD patients on maintenance haemodialysis (HD) with minimum 3 months dialysis vintage and functioning permanent vascular access are included for the study. Each participant had two sessions of HD at 37°C followed by two sessions at 35.5° C on a Fresenius 4008S HD machine. Systolic blood pressure (SBP), diastolic blood pressure (DBP) and Pulse rate are measured pre-HD, every hourly and post dialysis. Pre-HD Blood urea nitrogen (BUN) and post-HD BUN are measured, and Urea reduction rate was calculated for each HD session. Kt/V was calculated by ionic conductance by HD machine for each session. Results. 25 patients (5 females and 20 males) were enrolled. The mean age was 54 ± 9.58 years. Dialysis vintage was 21.48 ± 6.9 months for study participants 10 patients (40%) were diabetic nephropathy, 9 patients (36%) were presumed chronic glomerulonephritis, 2 patients (8%) were lupus nephritis and 4 patients (16%) were chronic interstitial nephritis. There was statistically no difference between pre-HD BUN (p = 0.330), post-HD BUN (p = 0.776), URR (p = 0.718) and Kt/V (p = 0.534) among the dialysis sessions done at 37°C and 35.5°C. SBP variability in the low temperature (35.5°C) group at 4th hour and post dialysis assumed statistical significance with p = 0.05 and p = 0.025 respectively. DBP variability in the low temperature (35.5°C) group at 3rd hour, 4th hour and post-dialysis demonstrated statistical significance with p = 0.027, p = 0.36 and p = 0.016 respectively. Pulse rate variability was more in the low temperature (35.5°C) group at 3rd hour and 4th hour which showed statistical significance with p = 0.037 and p = 0.05 respectively. Conclusion. Cool dialysate is non inferior to standard dialysate temperature in terms of dialysis adequacy and is associated with less variability in diastolic blood pressure, systolic blood pressure and more pulse rate variability thereby contributing to better hemodynamic stability.