What Is the Hemodialyzer Urea Clearance & Mass Transfer Calculator?
Dialyzer clearance Kd quantifies the effective volumetric cleansing rate of uremic toxins across hollow fiber membranes.
How Does the Hemodialyzer Urea Clearance & Mass Transfer Calculator Work?
Counter-current flow preserves a positive concentration gradient along the entire fiber length, governed by membrane KoA.
Hemodialyzer Urea Clearance & Mass Transfer Calculator Formula & Variables
The core mathematical equation utilized by this calculator is expressed as:
K_d = Q_b rac{expleft( rac{K_o A}{Q_b}(1 - Z)
ight) - 1}{expleft( rac{K_o A}{Q_b}(1 - Z)
ight) - Z}, quad Z = rac{Q_b}{Q_d}
Counter-current mass transfer dialyzer clearance equation.
How to Use the Hemodialyzer Urea Clearance & Mass Transfer Calculator
- Enter blood flow Qb, dialysate flow Qd, dialyzer KoA in mL/min, and pre-dialyzer solute concentration.
Step-by-Step Example Calculation
High-Flux Dialyzer Clinical Session
Input Values:
bloodFlowQbMlMin:400
dialysateFlowQdMlMin:600
koAMlMin:900
inletConcentrationMgDl:70
Worked Steps: Clearance Kd = 301 mL/min (75.3% extraction ratio), Solute removal rate = 211 mg/min.
Understanding Your Result
Outputs solute clearance Kd in mL/min, single-pass extraction ratio, and mass removal rate in mg/min.
Factors That Affect the Result
- Higher blood flow boosts clearance up to membrane diffusion limits; membrane KoA represents intrinsic membrane quality.
When Should You Use This Calculator?
- Prescribing clinical hemodialysis adequacy (Kt/V target >= 1.4) and sizing artificial kidney membranes.
Assumptions & Limitations
- Assumes negligible ultrafiltration convection contribution (pure diffusion model).
Frequently Asked Questions
Calculation Accuracy & Reference Note
Standard biomedical engineering dialyzer transport model.