Conventional blood sampling versus On-Line Clearance Monitoring.
On-line Clearance Monitoring (OCM) calculates the Kt/V during a dialysis session using a module incorporated into the Fresenius 4008 H/S haemodialysis machine (1). The method is based on repeated increments in dialysate sodium concentrations followed by measuring the change of dialysate sodium concentration after the dialysate has passed through the kidney. OCM is a patient friendly, non-invasive and easy method for measuring Kt/V. Kt/V calculated on single-pool urea kinetics according to Daugirdas was compared to Kt/V measured by OCM in thirty stable patients on chronic haemodialysis. Patients were dialysed using a dialyser with either a high-flux polysulfone or a haemophane membrane. In four patients OCM was measured in ten consecutive sessions to assess the intra-individual variation in OCM. The calculated Kt/V was compared to Kt/Vocm in three patients at five consecutive dialysis sessions to measure the intra-individual correlation. A linear correlation was present between Kt/Vocal and Kt/Vac for both the polysulfone and haemophane membrane. Intra-individual Kt/Vocm showed very stable values with an average variation of less than 5%. Intra-individual correlation between calculated Kt/V and Kt/Vocm was high.
Thomson
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Haemodialysis Unit, Rotterdam, The Netherlands. d.thomson@erasmusmc.nl
D015982:Bias; D001672:Biocompatible Materials / Q000592:standards; D001800:Blood Specimen Collection / Q000295:instrumentation / Q000379:methods* / Q000592:standards; D001806:Blood Urea Nitrogen; D001810:Blood Volume; D002482:Cellulose / Q000031:analogs & derivatives* / Q000592:standards; D005260:Female; D015312:Hemodialysis Solutions / Q000737:chemistry; D006801:Humans; D016014:Linear Models; D008297:Male; D008422:Materials Testing; D008657:Metabolic Clearance Rate; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods* / Q000592:standards; D011108:Polymers / Q000592:standards; D006435:Renal Dialysis / Q000295:instrumentation / Q000379:methods*; D051437:Renal Insufficiency / Q000378:metabolism / Q000628:therapy; D012727:Sex Characteristics; D012964:Sodium / Q000032:analysis; D013450:Sulfones / Q000592:standards; D013997:Time Factors; D014018:Tissue Distribution
D001672:Biocompatible Materials; D015312:Hemodialysis Solutions; D011108:Polymers; D013450:Sulfones; C054645:Hemophan; C017662:polysulfone P 1700; D002482:Cellulose; D012964:Sodium