CDN Dialysis Adequacy and Prescription

Question 1

What does the Kt/V measurement represent in hemodialysis?

Accepted Answer

Dialyzer clearance times treatment time divided by urea distribution volume

Answer

Kt/V is a dimensionless index where K=dialyzer urea clearance, t=treatment time, and V=patient's urea distribution volume, measuring dialysis dose.

Question 2

What is the minimum single-pool Kt/V (spKt/V) recommended by KDOQI guidelines for thrice-weekly hemodialysis?

Accepted Answer

1.2

Answer

KDOQI guidelines recommend a minimum spKt/V of 1.2 for patients on thrice-weekly hemodialysis to ensure adequate uremic toxin removal.

Question 3

Which factor would most directly increase the Kt/V delivered to a patient?

Accepted Answer

Extending the treatment time from 3 to 4 hours

Answer

Extending treatment time increases the total amount of urea cleared (K×t), thereby raising the Kt/V when urea distribution volume (V) remains constant.

Question 4

What is the primary purpose of using a high-flux dialyzer compared to a low-flux dialyzer?

Accepted Answer

Greater removal of middle molecules and beta-2 microglobulin

Answer

High-flux dialyzers have larger pores that allow removal of middle molecules and larger solutes like beta-2 microglobulin, which are associated with dialysis-related amyloidosis.

Question 5

A patient's pre-dialysis BUN is 80 mg/dL and post-dialysis BUN is 28 mg/dL. What is the urea reduction ratio (URR)?

Accepted Answer

65%

Answer

URR = [(Pre-BUN − Post-BUN) / Pre-BUN] × 100 = [(80−28)/80] × 100 = 65%, which meets the minimum recommended threshold of 65%.

CDN - Certified Dialysis Nurse Practice Test

CDN - Certified Dialysis Nurse Practice Test

CDN Dialysis Adequacy and Prescription