The Effect Of Increasing Dialysate Flow Rate In Hemodialysis

Abstract

Hemodialysis is a technique of removing, or clearing ,solutes from the blood and removal of extra fluid fromthe body, by using dialyzing machine and a dialyzerwhich is also known as (artificial kidney). The principleof hemodialysis is, primarily, the diffusion of solutesacross a semipermeable membrane and ultrafiltrationfor removal of extra fluid.The purpose of this study is to demonstrate the effect ofincreasing nominal dialysate flow rate from 500 ml/minto 800 ml/min on the amount of the small solutes (urea)removed from the blood and examine its effect on theamount of dialysis delivered.In this study the in vivo effects of increase in dialysateflow rate on the delivered dose of dialysis studied on 28maintenance hemodialysis patients.Hemodialysis was performed at dialysate flow rates 500and 800 ml/min. The patients treated two times per weekfor 3 hours. The results show increase in urea clearanceand dialysis adequacy, and a significant increase in theurea difference between pre- and post-blood ureaconcentration by increasing dialysate flow rate from 500to 800 ml/min.It can be concluded that hemodialysis with dialysateflow rate 800 ml/min should be considered in selectedpatients not achieving adequacy despite extendedtreatment times and optimized blood flow rate. Andincreasing nominal dialysate flow rate from 500 ml/minto 800 ml/min alters the mass transfer characteristics ofhollow fiber hemodialyzer and results in a largerincrease in urea clearance.