When a post-dialysis sample is suspected to be drawn incorrectly, the technician should verify:

• A. The post-dialysis sample was drawn correctly
• B. The post-dialysis sample was drawn incorrectly
• C. The pre-dialysis sample was drawn correctly
• D. The BUN value was discarded

Answer: (A)

When assessing dialysis adequacy, the value obtained from the post-dialysis sample is only meaningful if the specimen was collected properly. If there’s suspicion the post-dialysis draw might be flawed, the technician should verify that the post-dialysis sample was drawn correctly—timed right after the end of dialysis, obtained with proper venipuncture technique, using the correct tube, and handled and labeled properly to avoid contamination or hemolysis. Confirming correct collection ensures the result reflects true post-dialysis conditions; if the sample wasn’t drawn correctly, it should be redrawn using proper technique. This focus on the sample’s validity is essential before interpreting the BUN or other markers to judge dialysis adequacy.