Objective To examine the association of arteriovenous fistula (AVF) blood flow(Qa) dynamics with inflammation state and its effect on cardiovascular diseases (CVD) in maintenance hemodialysis (MHD) patients. Methods Thirty MHD patients with AVF and twelve healthy people were enrolled in the study. Qa and cardiac output (CO) were measured by Transonic Hemodialysis Monitor HD 02. In MHD patients, pre-dialysis blood samples were taken before Qa monitoring. High-sensitivity C-reactive protein (hsCRP) was measured by immunoturbidimetry (Kyoma, Japan). Inflammatory factors IL-2, IL-6, IL-10, TNF were measured by Cytometric Bead Array (BDTM). Cardiovascular diseases morbidity was monitored prospectively within nineteen months follow-up period. Results There were no significant differences in age and sex between MHD patients and healthy people. The serum IL-6, IL-10, TNF and hsCRP were significantly higher in MHD patients than those in healthy controls [2.38 (1.86-4.69) vs 1.14 (0.27-1.18) ng/L, P<0.01; 1.47 (1.19-2.10) vs 1.04 (0.00-1.23) ng/L, P<0.01; 1.33 (1.05-1.56) vs 0.54 (0.00-1.24) ng/L, P<0.05; 4.90 (1.58-7.45) vs 1.50 (0.63-1.90) mg/L, P=0.01]. During the follow-up period, 6 patients (20.0%) developed at least one episode of cardiovascular event. Qa, serum IL-6 and hsCRP levels were significantly higher in patients with CVD as compared to those without CVD [(1120±192) vs (893±189) ml/min, P<0.05; 4.86 (2.96-7.85) vs 2.20 (1.80-3.10) ng/L, P<0.01；11.75 (3.83-31.53) vs 4.45 (1.05-6.68) mg/L, P<0.05]. Binary Logistic regression analysis demonstrated that serum IL-6 was an independent and stronger risk factor for CVD morbidity [HR=1.943, 95%CI（1.110-3.402）, P=0.02]. Spearman rank correlation analysis and liner regression analysis showed that Qa was positively correlated with serum IL-6 (β=0.492, P<0.01). Path analysis suggested that Qa contributed to CVD mortality via the increase of serum IL-6. Conclusions AVF blood flow monitoring is important for MHD patients. IL-6 is an independent risk factor of CVD in MHD patients. AVF blood flow increases cardiovascular diseases morbidity in MHD patients via its promotion of IL-6 production.

Objective To report a simple formula to estimate phosphate removal by standard four-hour hemodialysis in Chinese patients. Methods A total of 165 MHD patients in Huashan Hospital were enrolled. Effluent dialysate samples were collected during treatment to estimate the total amount of phosphate removal. Pre-dialysis levels of serum phosphate, potassium(K+), hematocrit(Hct), parathyroid hormone(iPTH), carbon dioxide combining power(CO2CP), alkaline phosphatase (AKP), Kt/V, and ultrafiltration volume, age, gender, dry body weight, blood flow, phosphate clearance of dialyser, phosphate concentration of dialysate at 60 min after the start of HD were obtained. 80% observations were randomly selected for formula building by backward stepwise and the remaining 20% observations were used to validate the formula. Results The formula was described as Tpo4=88.6×C60-0.03×Age+1.07×Gender+0.06×Clearance-4.59, where C60 was phosphate concentration in dialysate measured 60 min into HD and Clearance was the phosphate clearance of dialyser. Formula validation further suggested good predictive ability. Conclusion This study derives an approach to quantify phosphate removal by a simple formula, which will be helpful for clinicians to treat patient individually.