| Laboratory: | Clinical Biochemistry |
| Test Name: |
FRACTIONAL EXCRETION OF SODIUM - (P and U) or (S and U)
Test Code:
Plasma or Serum: NA, CR........Urine: NAU, CRU
|
| Clinical Information: |
Serum is also acceptable. Physician ordering the test will perform the calculation.
FE of Sodium = urine sodium x plasma creatinine plasma sodium urine creatinine |
| Collection Devices: |
Preferred Devices:
- And -
|
| Specimen Required: |
Plasma: 0.5 mL
AND 2 mL random urine. Blood and urine must be collected at approximately the same time (no more than 3 hours apart). |
| Referral: |
Serum: 1.0 mL
AND 5.0 mL random urine. Blood and urine must be collected at approximately the same time (no more than 3 hours apart).
|
| Requisition: | |
| Reference Values: |
< 1 suggests prerenal failure.
> 3 suggests acute tubular necrosis. |
| Availability: |
Weekdays
|
| See Also: | |
| More Information: |
Laboratory will order and report sodium and creatinine values for both plasma (or serum) and urine.
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