Increased efficiency of hemodialysis with citrate dialysate: a prospective controlled study.

A bicarbonate dialysate acidified with citrate (CD) has been reported to have local anticoagulant effect. This study examines the effect of CD on dialysis efficiency, measured as eKt/Vurea, and predialysis concentrations of BUN, creatinine, phosphate, and beta-2 microglobulin in chronic dialysis units. Three outpatient chronic hemodialysis units with 142 patients were switched to CD for 6 mo. Using each patient's prior 6 mo on regular bicarbonate dialysate acidified by acetate (AD) as control, eKt/Vurea was compared with that of CD. Follow-up data for 7 mo after the study were collected from about one-half of the participants remaining on CD and the others returned to AD. eKt/Vurea, increased (P < 0.0001) from pre-CD value of 1.51 +/- 0.01 to 1.57 +/- 0.01 with CD. During CD use beta-2 microglobulin levels declined (P = 0.0001) from 28.1 +/- 10.0 to 25.9 +/- 10.0. Similarly, the concentrations of BUN, creatinine, and phosphate also decreased on CD (P < 0.008). In the poststudy period, eKt/Vurea for the patients staying on CD remained unchanged at 1.60 +/- 0.17 versus 1.59 +/- 0.18 (P = NS), whereas in those returning to AD the eKt/Vurea decreased from 1.55 +/- 0.20 to 1.52 +/- 0.17 (P < 0.0001). Data suggest that CD use is associated with increased solute removal.