Improvement of autonomic nervous regulation by blood purification therapy using acetate-free dialysis fluid - clinical evaluation by laser Doppler flowmetry

Abstract

In Japan, acetate-free biofiltration (AFBF) became commercially available in the year 2000, and these products have been reported to be clinically effective for controlling the decrease of blood pressure during dialysis or various types of dialysis intolerance. And more, acetate-free dialysis fluid was made clinically available in 2007, acetate-free hemodialysis (AFHD) is expected to inhibit the malnutrition-inflammation-atherosclerosis syndrome, improve anemia and the nutritional status of patients, stabilize hemodynamics, and reduce inflammation and oxidative stress. In a broad sense, AFBF can be classified as hemodiafiltration (HDF), and its clinical effects seem to be associated with multiple factors, including use of acetate-free dialysis fluid, massive removal of low molecular weight proteins by convection, and the sodium concentration of the replacement fluid. Therefore, the clinical significance of acetate-free dialysis fluid could be demonstrated more clearly by comparing AFHD with conventional hemodialysis (conv. HD) using dialysis fluid containing about 10 mEq/l acetate. Since 2005, we have been investigating the efficacy of various modalities of blood purification therapy by continuously monitoring changes of tissue blood flow in the lower limbs and earlobes (head) using non-invasive continuous monitoring method (NICOMM). In this report, we assess the clinical effectiveness of AFHD on the basis of clinical findings and head stability index (head SI) obtained by NICOMM, particularly with respect to the influence on autonomic regulation. After switching to AFHD from conv. HD, anemia, stored iron utilization, and the frequency of treatments for dialysis hypotension and of muscle cramps were significantly improved. Further, the head SI was also significantly smaller with AFHD than conv. HD. This finding suggests that AFHD improved the maintenance of homeostasis by the autonomic nervous regulation system. In addition, we could not find clinical features of excessive alkalosis during an observation period of about 1 year, even if online HDF using acetate-free dialysis fluid as the substitution fluid. Our conclusion is that the advent of acetate-free dialysis fluid has led to investigations into new clinical effectiveness of AFHD or online HDF/HF using ultrapurified acetate-free dialysis fluid as the substitution fluid.