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Osmolality, serum
| Item | Value |
|---|---|
| Approval req'd? | No |
| Available Stat? | Yes |
| Test code | OSM |
| Test group | Osmolality |
| Performed by | Parnassus Chemistry |
| In House Availability | Test available 24 hours per day 7 days per week |
| Method | Freezing point depression |
| Container type | Gold top or Light Green top |
| Amount to Collect | 0.8 mL blood Click here for Microdetermination info |
| Sample type | Serum |
| Preferred volume | 0.4 mL serum |
| Min. Volume | 0.1 mL serum Click here for Microdetermination info |
| Units | mmol/kg |
| Normal range | 283-301 mmol/kg |
| Critical value | < 240 mmol/kg or > 320 mmol/kg |
| Synonyms | Ethanol; osmolar gap; ethylene glycol; methanol |
| Stability | Refrigerated 1 week |
| Turn around times | STAT 1 hour, Routine same or next day |
| Additional information | Each 0.10 g/dL of ethanol contributes about 22 mmol/kg to the endogenous osmolality of serum. Predicted value = 2xNa [mmol/L] + Glucose [mg/dL]/18 + BUN [mg/dL]/2.8. A measured value exceeding the predicted value by > 10 is consistent with, e.g., ethanol, methanol or ethylene glycol ingestion. If specific testing for methanol, ethylene glycol and/or isopropanol is desired see entry for Drug screening - Volatiles |
| LOINC code | 2692-2 |
| Last Updated | 10/8/2010 2:57:17 PM |
| Entry Number | 698 |
| Lab Procedure Link | Click here for osmometer information |
If you have additional questions regarding this test, please call: 415-353-1667