Clinical Hemodialysis Delivery System Test Bench
Provides calibrated peristaltic blood pump and heated, degassed dialysate preparation system.
Biomedical Engineering / Hemodialyzer Urea Clearance
FREE TO EXPLORELABORATORY 32 · BIOMEDICAL ENGINEERING
Hollow-Fiber Hemodialyzer Urea Clearance & Mass Transfer Coefficient
Evaluate small-solute (urea) clearance K_u of a clinical hollow-fiber hemodialyzer across varying blood flow rates Q_b at fixed dialysate flow rate Q_d. Explore interactive physiological instrumentation simulation, biomechanics, and biomedical engineering telemetry.
BIOINSTRUMENTATION · BIOSIGNALS · BIOMECHANICS · IMAGING
Your virtual biomedical engineering laboratory.
DIALYTIC UREA CLEARANCE K_U—
PHYSIOLOGICAL & TEST CELL TELEMETRY
Ready to sample with Blood Flow Q_b = 250.0 mL/min.
Adjust Blood Flow Q_b, then execute biomedical trial.
Biomedical engineering telemetry and physiological states are evaluated rigorously using 64-bit IEEE 754 precision. Residuals reflect ordinary least-squares regression across successive observations. Continuous data structures support high-fidelity biological and physiological modeling.
Biomedical assumptions and boundary condition limits
The linear clearance-flow model applies across standard clinical blood flows (150 to 400 mL/min); at extreme flows (> 500 mL/min), clearance plateaus asymptotically. Evaluated on a 1.8 m² high-flux polysulfone hollow-fiber hemodialyzer (Fresenius FX80, mass transfer-area coefficient K_0·A = 950 mL/min for urea). Constant counter-current dialysate flow Q_d = 500 mL/min at 37.0 °C with zero ultrafiltration (Q_f = 0). Linear blood flow clearance slope m_c = 0.5800 with baseline K_u0 = 42.0000 mL/min across blood flow rates Q_b from 150 to 400 mL/min.
Biomedical apparatus & physiological sensors.
High-Flux Polysulfone Hollow-Fiber Dialyzer (1.8 m²)
Contains ~12,000 semipermeable hollow fibers with 1.8 m² effective mass transfer surface area.
Closed-Loop Synthetic Blood Reservoir (Urea 25.0 mmol/L)
Provides standardized blood substitute containing physiological electrolytes and clinical urea concentration.
Counter-Current Dialysate Proportioning Circuit (500 mL/min)
Prepares bicarbonate-buffered dialysate at 37.0 °C and meters counter-current flow through shell side.
Automated Spectrophotometric Enzymatic Urea Analyzer
Measures blood inlet (C_bi) and outlet (C_bo) urea concentrations using the urease-GLDH method.
Dual Ultrasonic In-Line Flow Transducers
Continuously measures blood compartment flow Q_b and dialysate flow Q_d with 1 mL/min accuracy.
FOLLOW THE METHOD
A reason behind every step.
Evaluate small-solute (urea) clearance K_u of a clinical hollow-fiber hemodialyzer across varying blood flow rates Q_b at fixed dialysate flow rate Q_d. Standardized parameter settings: 150.0, 200.0, 250.0, 300.0, 350.0, 400.0 mL/min.
01
Dialyzer Priming and Air Purging
Mount dialyzer vertically, prime blood side with 1 L heparinized saline at 150 mL/min to displace air, and invert to purge dialysate compartment.
02
Dialysate Temperature and Flow Stabilization
Set dialysate delivery to 500 mL/min at 37.0 °C with bicarbonate conductivity 14.0 mS/cm and verify zero ultrafiltration transmembrane pressure.
03
Blood Reservoir Urea Standardization
Prepare synthetic blood reservoir with urea concentration C_bi = 25.0 mmol/L (150 mg/dL BUN) at 37.0 °C under gentle magnetic stirring.
04
Blood Flow Step Initialization
Set blood pump to delivery rate Q_b = 150 mL/min, circulate counter-current to dialysate, and allow 5 minutes for concentration steady state.
05
Paired Blood Sampling and Urea Assay
Simultaneously sample inlet port (C_bi) and dialyzer outlet port (C_bo), assaying urea concentrations via spectrophotometric enzymatic assay to calculate clearance K_u.
06
Blood Flow Progression and Regression Analysis
Repeat sampling at Q_b = 200, 250, 300, 350, and 400 mL/min, plot urea clearance K_u versus Q_b, and determine flow sensitivity slope m_c.
07
Mass Transfer-Area Coefficient K_0·A Calculation
Verify dialyzer performance against the theoretical logarithmic mean mass transfer relation K_0·A = [Q_b·Q_d / (Q_d - Q_b)] · ln[(1 - K/Q_d)/(1 - K/Q_b)].
YOUR NOTEBOOK · 0 OBSERVATIONS
Turn measurements into biomedical engineering insight.
Points are your recorded observations. The solid regression line validates Hemodialyzer Urea Clearance mathematical scaling.
LINEAR REGRESSION FIT · y = mx + b
K_u = m_c · Q_b + K_u0 = 0.5800 · Q_b + 42.0000
| # | Blood Compartment Flow Rate Q_b (mL/min) | Dialytic Urea Clearance K_u (mL/min) | Blood flow rate Q_b (mL/min) | Urea clearance K_u (mL/min) | Remove |
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