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HelpTest Code RI Renal Failure Indices
Synonyms/Keywords
Fractional Excretion of Sodium, Renal Failure Index, RFI
Specimen Requirements
|
Specimen Type |
Preferred Container/Tube |
Acceptable Container/Tube |
Specimen Volume |
Specimen Minimum Volume (allows for 1 repeat) |
Pediatric Minimum Volume (no repeat) |
|
Urine |
Urine without preservative |
Urine with 0.5 g sulfamic acid, 6N HCL, 33% acetic acid, or boric acid |
10 mL |
0.5 mL |
|
|
Plasma/Serum (*See Collection Instructions) |
Lithium-heparin Plasma Separator Tube (PST) |
Serum Separator Tube (SST), Lithium or Sodium-Heparinized Green Top Tube (GTT), or Red Top Tube (RTT) |
1 mL |
0.3 |
|
Collection/Processing Instructions
*If there is no other blood creatinine or sodium order on the same encounter within 8 hours of urine collection, a blood order of RI-BLD (Renal Indices-Blood) will be reflexed when the urine order is completely activated and should be drawn upon receipt of urine.
Note: Blood specimens are acceptable no earlier than 8 hours prior to the start of the urine collection or no later than 8 hours after the collection ends.
Random urine without preservative is preferred.
Specimen Stability Information
| Specimen Type | Temperature | Time |
| Urine - No Preservative | Refrigerate | 4 days |
| Urine - W/Preservative | Refrigerate | 7 days |
| Plasma/Serum | Ambient | 5 days |
| Refrigerate | 7 days |
Rejection Criteria
If either the blood or urine specimen is not available, the test cannot be performed
Test Components
Urine Creatinine and Sodium
Blood Creatinine and Sodium
Reference Range Information
| Performing Location | Reference Range |
|---|---|
| Marshfield | <1 implies pre-renal azotemia Values >1 may indicate acute renal failure |
Marshfield Labs Performing Department
Marshfield Labs Chemistry
Performing Information
| Performing Location | Day(s) Test Performed | Analytical Time | Methodology/Instrumentation |
|---|---|---|---|
| Marshfield | Monday through Sunday | Less than 2 hours | Modified Jaffe Kinetic Fixed Assay & ISE/Beckman Coulter AU |
CPT Codes
| CPT | Modifier (if needed) |
Quantity | Description | Comments |
|---|---|---|---|---|
| 84300 | Sodium, urine | |||
| 82570 | Creatinine, other source | |||
| 84295 | Sodium, serum | If needed | ||
| 82565 | Creatinine, blood | If needed |
Outreach CPT Codes
| CPT | Modifier (if needed) |
Quantity | Description | Comments |
|---|---|---|---|---|
| 84300 | Sodium, urine | |||
| 82570 | Creatinine, other source | |||
| 84295 | Sodium, serum | If needed | ||
| 82565 | Creatinine, blood | If needed |
Ordering Applications
| Ordering Application | Description |
|---|---|
| 4medica | Renal Failure Indices |
| Cerner | Renal Failure Index Renal Failure Indices |