RESUMO
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.