BACKGROUND: Ultraviolet (UV) absorbance of spent dialysate has been proposed as a method for monitoring hemodialysis efficiency. The contribution of the various uremic toxins to UV absorption, however, needs clarifying. METHODS: Urea, creatinine and uric acid were measured in blood and dialysate before and during dialysis in 22 maintenance hemodialysis patients. Absorbance was measured in dialysate. RESULTS: High-performance liquid chromatography (HPLC) analyses of dialysate revealed uric acid as the predominant peak. Spent dialysate absorbance decreased, during dialysis, similarly to serum and dialysate urea, creatinine and uric acid. Dialysate urea correlated closely with absorbance, though urea did not contribute to absorbance, which was determined mostly by uric acid. Uric acid and urea removals were very similar. The spectrophotometric Kt/V correlated with spKt/V urea, with slight but significant differences between the two measurements. CONCLUSIONS: UV absorbance is determined mostly by uric acid. Absorbance measurements seem suitable as a method for monitoring dialysis efficiency.
BACKGROUND: Ultraviolet (UV) absorbance of spent dialysate has been proposed as a method for monitoring hemodialysis efficiency. The contribution of the various uremic toxins to UV absorption, however, needs clarifying. METHODS:Urea, creatinine and uric acid were measured in blood and dialysate before and during dialysis in 22 maintenance hemodialysis patients. Absorbance was measured in dialysate. RESULTS: High-performance liquid chromatography (HPLC) analyses of dialysate revealed uric acid as the predominant peak. Spent dialysate absorbance decreased, during dialysis, similarly to serum and dialysate urea, creatinine and uric acid. Dialysate urea correlated closely with absorbance, though urea did not contribute to absorbance, which was determined mostly by uric acid. Uric acid and urea removals were very similar. The spectrophotometric Kt/V correlated with spKt/V urea, with slight but significant differences between the two measurements. CONCLUSIONS: UV absorbance is determined mostly by uric acid. Absorbance measurements seem suitable as a method for monitoring dialysis efficiency.
Authors: Raymond Vanholder; Rita De Smet; Griet Glorieux; Angel Argilés; Ulrich Baurmeister; Philippe Brunet; William Clark; Gerald Cohen; Peter Paul De Deyn; Reinhold Deppisch; Beatrice Descamps-Latscha; Thomas Henle; Achim Jörres; Horst Dieter Lemke; Ziad A Massy; Jutta Passlick-Deetjen; Mariano Rodriguez; Bernd Stegmayr; Peter Stenvinkel; Ciro Tetta; Christoph Wanner; Walter Zidek Journal: Kidney Int Date: 2003-05 Impact factor: 10.612
Authors: Jana Jerotskaja; Fredrik Uhlin; Ivo Fridolin; Kai Lauri; Merike Luman; Anders Fernström Journal: Blood Purif Date: 2009-12-03 Impact factor: 2.614