Test Code BUN Blood Urea Nitrogen
Aliases
Urea
Patient Preparation
No special patient preparation required
Collection Method
Venous collection
Minimum Volume
- Adults: 0.8ml
- Pediatric: 0.5mL
Container
Lt Green / Plasma Separator / Lithium Heparin
Preferred Specimen
Light Green Top (lithium heparin) plasma
Acceptable Specimens
Serum:
- Gold Top SST
- Red Top
Plasma:
- Light Geen Top (lithium heparin)
Reference or Target Ranges
| 0 – 1 year | 4 – 19 mg/dL |
| 1 year – 18 years | 5 – 18 mg/dL |
| 18 years – 60 years | 6 – 20 mg/dL |
| >60 years | 8 – 23 mg/dL |
Reportable Units
mg/dL
Critical Value
≥80 mg/dL
Reasons for Rejection
| Hemolysis Threshold | 131 mg/dL |
| Icterus Threshold | 20 mg/dL |
| Lipemia Threshold | 500 mg/dL |
| Other | QNS, contaminated, improperly Labeled, improper specimen type |
Specimen Stability
| Ambient | 7 days |
| Refrigerated (4°C to 8°C) | 7 days |
| Frozen(-40°C to 0°C) | 1 year |
Performance Information
| Days and Time Performed | 24/7 |
| Expected Turn Around Time |
Stat: 1 hour Routine: 4 hours |
| Stat Availability | Yes |
| Performing Bench | UH Chemistry |
| Methodology/Method Description | Siemens Atellica – Colorimetric |
CPT Codes
84520