Dialysis Adequacy and Prescription Flashcards

What does the Kt/V measurement represent in hemodialysis?

Answer: Dialyzer clearance times treatment time divided by urea distribution volume

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

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

Answer: 1.2

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

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

Answer: Extending the treatment time from 3 to 4 hours

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

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

Answer: Greater removal of middle molecules and beta-2 microglobulin

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.

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)?

Answer: 65%

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

What is the recommended target URR for hemodialysis patients according to current guidelines?

Answer: ≥65%

Current guidelines recommend a minimum URR of 65% for hemodialysis patients, corresponding to an spKt/V of approximately 1.2.