Hemodialysis Adequacy

Abstract

Hemodialysis adequacy is assessed by both clinical as well as urea removal. Urea reduction ratio and Kt/V are commonly used measures of urea removal.

Appendix

• 1. Calculate URR with following values. Pre-dialysis urea = 100 mg/dL and post-dialysis urea = 40 mg/dL.

  $$ \mathrm{URR}=\left(\mathrm{pre}-\mathrm{dialysis}\ \mathrm{urea}-\mathrm{post}-\mathrm{dialysis}\ \mathrm{urea}\right)\times 100\div \mathrm{pre}-\mathrm{dialysis}\ \mathrm{urea} $$
  $$ \mathrm{URR}=\left(100-40\right)\div 100 $$

  URR = 60%

• 2. Calculate the required session length of dialysis with the following values:

  K0A of dialyzer: 800 Urea clearance of dialyzer at QB of 400 mL/min = 250 mL/min Volume of distribution of urea = 40 L spKt/V = 1.5

  In the formula spKt/V = 1.5, we must calculate “t”. Substitute V = 40 L (i.e., 40,000 mL) and K = 250.

  250 × t/40,000 = 1.5.

  t = 40,000 × 1.5/250.

  t = 240 min = 4 h.

  The dialysis session length must be 4 h if we use a dialyzer with K₀A of 800.