Minutes of Hemodialysis Completed When Blood Urea Nitrogen (BUN) Sample Is Drawn
Records the number of minutes of hemodialysis completed when the blood urea nitrogen sample was collected. This timing helps interpret BUN results and assess dialysis treatment.
This result documents when the BUN sample was taken during hemodialysis so it can be interpreted alongside other dialysis information.
Key facts at a glance
- LOINC
- 70956-8
- Short code
- MINUTESOFHEMODIALYSISCOMPLETEDWHENBUNDRAWN
- Synonyms
- —
- Category
- kidney
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 7
- Ref high
- 20
- Critical range
- — – 100 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- esrd
- CPT
- 84520
- SNOMED
- 2739004
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What is this test?
This is a timing record used with blood urea nitrogen (BUN) testing during hemodialysis. It states how many minutes of dialysis had been completed when the blood sample was drawn.
Why might I need this test?
The timing is important when BUN measurements taken before and after dialysis are compared to help evaluate dialysis adequacy. It also allows the dialysis team to interpret the BUN value in the context of the treatment actually delivered.
How is the test performed?
The dialysis unit records the treatment time when the BUN sample is collected. It is generally part of routine dialysis documentation and does not require a separate procedure beyond the scheduled blood draw.
How do I prepare for the test?
Follow the dialysis center's instructions for blood sampling. The sample is usually collected through the dialysis access, and the exact collection time during treatment should be documented by staff.
Reference range
Adult: 7-20 mg/dLN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This timing value is not inherently abnormal; its meaning depends on the BUN result and the other dialysis information. A smaller-than-expected decrease in BUN after dialysis may prompt review of treatment adequacy, but it can also reflect sampling or treatment-timing differences. Your dialysis team interprets these results together rather than relying on this timing value alone.
Short name
Hemodialysis BUN Draw Timing
Frequently asked questions
Does this result measure how well my dialysis is working?
Why does it matter whether the BUN is drawn early or late in dialysis?
Will I need a special blood draw for this timing record?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy