Effect of cool temperature dialysate on the quality and patients' perception of haemodialysis

Background. The effects of cool dialysate on the urea reduction ratio (URR) in high efficiency haemodialysis have not been completely studied. After reviewing the literature, it appeared that patients' perceptions of cool dialysis have not been studied. Since patients' perception have an impact on patient satisfaction, this motivated the authors to research this area of practice. Methods. This study was designed to determine whether a high URR and haemodynamic stability could be achieved by using cool dialysate in two groups of patients. The first group of five patients were known to have hypotension episodes during dialysis, and the second group of five patients were documented as having stable blood pressure (BP) during and after dialysis, after excluding vascular access recirculation and any other problems. Each patient was dialysed for three sessions using cool dialysate (35degreesC) followed by another three sessions using a standard dialysate temperature (36.5degreesC). All other dialysis session parameters were maintained. Results. The results show that the dialysate cooling resulted in an increased ultrafiltration in the low BP group (P = 0.05). Cool dialysis had neither an adverse nor a beneficial effect on urea removal in the two groups (P = NS). The mean arterial pressure post- and intra-dialysis was significantly higher in dialysis with cool dialysate in the low BP group (P < 0.01 and P < 0.007, respectively). The mean arterial pressure in the stable BP group remained unchanged when cool dialysate was used (P = NS). The intra-dialytic pulse rates in the low and stable BP groups were similar. A total of seven episodes of symptomatic hypotension were observed in the low BP group, but none in the stable BP group (P < 0.0001). Patients' perceptions about cool dialysate were measured by a questionnaire which showed that 80% of them felt more energetic after dialysis and requested to be always dialysed with cool dialysate. Conclusion. Cool dialysate improves tolerance for dialysis in hypotensive patients and helps increase ultrafiltration while maintaining haemodynamic stability during and after dialysis. Patients' perceptions were positive, as most of the selected sample felt more energetic and generally well during and after dialysis, and this had a positive impact on their activities of daily living.