Exploration of the effect of haemodialysis modality on blood pressure in patients with End Stage Kidney Disease

Abstract

New haemodialysis modalities have been developed with the intention of improving haemodialysis adequacy and blood pressure control. One such device, online haemodiafiltration, has been shown to improve patient outcomes in international studies, with the possible exception of its effects on blood pressure control. This study compared the impact of online haemodiafiltration on blood pressure with that of standard haemodialysis in patients with chronic kidney disease in New Zealand. Methods A retrospective clinical audit was conducted. A total of eighty three eligible patients received haemodialysis treatment three times each week between June 2008 and November 2008 at Auckland Renal Services. Of those, fifty two patients met the inclusion criteria. Clinical charts, haemodialysis observational records, monthly blood test and medication charts were reviewed for the months of June and November 2008. Blood pressure readings across twelve haemodialysis sessions of both standard haemodialysis and online haemodiafiltration were analysed. ii Results The results show no overall significant difference between mean pre- and post-dialysis systolic blood pressure for either mode of haemodialysis. However, pre- and post-dialysis blood pressure differed significantly between ethnic groups (a Maori and Pasifika group, and an European, Asian and Other group). Also, mean pre- and post-dialysis diastolic blood pressure were continuously lowered in online haemodiafiltration compared with standard haemodialysis. A greater proportion of patients achieved the post-dialysis target blood pressure (mean 39.5% in both sHD and oHDF) recommended by Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines, than the figure for those who achieved the pre-dialysis target blood pressure (mean 34.3% in sHD and 32.8% in oHDF), in both groups. In addition, more patients experienced intradialytic hypotension in the oHDF group (11.2%) than the sHD group (8.91%). Conclusion Despite the improvement in haemodialysis techniques in recent years, stabilising blood pressure in haemodialysis patient remains challenging in all countries. Currently, there have been limited studies available on haemodialysis patients in New Zealand. Therefore, this study suggests that there is a need for further exploration and a match control study in the development of a target blood pressure for the New Zealand haemodialysis setting to improve the outcome of patient care.