Abstract: 【Abstract】 Objective To analysis the relationship between body-fluid distribution before hemodialysis and intradialytic-hypotension (IDH) among maintenance hemodialysis (MHD) patients，and to provide clinically basis for preventing IDH. MethodsDataofbody-fluid distributionpre-hemodialysis measured by Bio-impedance Electrical Spectroscopy（BIS）and blood pressure changes during hemodialysis were recorded in 620 hemodialysissessionsof 42 MHD patients in 6 weeks. According to the occurrence of IDH，620 hemodialysis sessions were divided into hypotension group and Non-hypotension group. Body-fluid distribution and blood pressure changes were compared between the two groups. Furthermore Logistic regression analysis was use to access the risk factors of IDH among body-fluid distribution. 143 IDHs occurred in 620 hemodialysis sessions, incidence rate of IDH was 23.06%. Logistic regression analysis revealed that Extracellular Fluid (ECV)、systolic pressure、total water/weight ratio(TW/W) of pre-hemodialysis and ultrafiltration speed(UFS) calculated by TW removed （ml/kg.min）were risk factors for IDH（P＜0.05）. ROC curve was used to predict IDH among risk factors pre-hemodialysis. UFS was correlated with IDH, the area under the ROC curve (AUC) of IDH was 0.680 (95% CI: 0.632～0.727，P=0,000),the sensitivity and specificity for IDH were 89.5% and60.5% respectively when the cutoff value was 0.198ml/kg.min. Conclusion Higher ultrafiltration speed、higher systolic pressure、total water/weight ratio of pre- hemodialysis were risk factors for IDH. Ultrafiltration speed calculated by TW removed of pre-hemodialysis can be used for predicting IDH.

Key words: Maintenance hemodialysis, Intradialytic-hypotension, Body-fluid distribution, Bio-impedance Electrical Spectroscopy