Authors
Abstract
In Hemdialysis ,blood is pumped from the body to special filter (dialyzer ) made
of tiny plastic capillaries . the blood is purified when the waste products diffuse from
the blood across the membrane of these tiny capillaries to the dialysate purified
“clean”blood is then returned to the body and spent dialysate is drained.
The purpose of this study is demonstrate the effect of increase nominal dialysate
flow rate from 500-800 ml/min on the amount of the small solute (urea) removed from
the blood and examine its effect on the amount of dialysis deliverd.
Hemdialysis (HD) is a technique of removing or clearing solutes from the
blood and removal of extra fluid from the body, by using dialyzing machine. The
principle of hemodialysis is primarily, the diffusion of solutes and ultrafiltration for
removal of extra fluid. Kinetic modeling is a widely used analytic process that
describes a system from its mass balance the clinical goals of modeling in dialysis
therapy are to improve clinical understanding of the uremic syndrome and quantified
doses of dialysis . In this study, we are interested for new model emerges form
generalization of signal–pool urea kinetic model (variable volume single pool VVSP)
which able to yield an accurate estimate of urea kinetic model such as urea nitrogen
generation rate, urea removal during dialysis and dialyzer urea clearance for
quantifying and prescribing dialysis. The mathematical development of the variable
volume single pool ( VVSP) model for application is based primarily on the three
blood samples. This development provides a method to combine all of the treatment
parameters (Vt,PCR,G),urea is unique among the possible markers in providing
information regarding a patients nitrogen balance . Urea concentration is directly
related to the protein catabolic rate blood urea concentrations reflected the balance
between protein catabolism and clearance. We present the results obtained form a
clinical study carried out on a group of 12 end stage renal disease (ESRD) patients for
blood flow rate less than 200ml/min and greater than 200ml/min, 6 patients with
dialysate flow rate (DFR) 500 ml/min and 6 patients with DFR 800 ml/min to show
the different in variable volume single pool (VVSP ) models for both groups (500 &
800 ml/min) this method done typically in patients treated with HD twice-weekly so a
standard modeling techniques include a standard blood urea nitrogen (BUN) samples
which are drawn before the beginning of HD, after the end of HD, and before the
beginning of the next HD and considering that volume changes occurring over the dialysis cycle this is the key idea that underlies the variable volume single-pool
(VVSP)model.
Keywords
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