Abstract: Objective To explore reused dialyzer efficiency of high flux dialyzer F50 and standard dialyzer F6 through on-line clearance measurement (OCM). Methods Kt/V value was measured by OCM in sixty hemodilysis patients. Total column volume (Tcv) and pressure were measured after the dialyzers were used for the first, third, sixth and ninth time. Results Kt/V value measured by OCM had no significant difference using reused F50 and F6 dialyzers compared with new F50 and F6 dialyzers.There was no significant difference of Kt/V value measured by OCM or by urea kinetic model. However, Tcv of 90% of the ninth time reused F6 dialyzer decreased more than 20%. Conclusions Both clearance efficiency and hollow fiber quality of the ninth time reused F50 dialyzer do not markedly change compared to its first time using in hemodialysis, but Tcv of 90% the ninth time reused F6 dialyzer decrease more than 20% though their Kt/V value does not decrease compared with new dialyzers.

Key words: Total column volume, Reused dialyzer