Ethanol/Volatiles Screen (EVS)
| Order Code: | EVS |
| Epic Lab Code: | LAB604 |
| Order Form: | A-1a General Lab or Epic Req |
Chemistry
6240 RCP
356-3527
6240 RCP
356-3527
Specimen:
Plasma
Collection Medium:
 |
| Plasma Separator Tube |
Alternate
Collection Media:
Call laboratory for additional acceptable specimen collection containers.
Minimum:
3 mL whole blood from light green top tube or TWO microtainers
Rejection Criteria:
Medico-legal specimens are not accepted.
Delivery Instructions:
Deliver to laboratory within 1 hour of collection.Testing Schedule:
24 hrs/day, 7 days a week, including holidays.
Turn Around
Time:
1 hour (upon receipt in laboratory)
Reference Range:
None detected. Ethanol intoxication begins in the 50-100 mg/dL range.
Critical value: >300 mg/dL
Comments:
Includes plasma ethanol by enzymatic analysis, plasma osmolality by
freezing point depression osmometry and a calculated osmolality using
plasma sodium, glucose and urea at no extra charge. See "Osmolality
Gap - Calculation and Interpretation" for more detailed
information.
Samples with unexplained osmolar gap greater than 15 have "Ethylene glycol, plasma" (by immunoassay) run reflexively. For those samples, if the ethylene glycol plasma concentration does not account for the high osmolar gap, the pathology resident on-call is contacted. The resident will then investigate the case and contact the clinical service, if indicated. Elevated osmolar gaps may also be caused by methanol, isopropanol, propylene glycol, activated charcoal, mannitol, renal failure, and diabetic ketoacidosis, as well as by heavy ethanol consumption with high concentrations of ethanol metabolites (in some cases with little or no ethanol remaining) as may be seen in alcoholic ketoacidosis.
Availability: as needed.
Samples with unexplained osmolar gap greater than 15 have "Ethylene glycol, plasma" (by immunoassay) run reflexively. For those samples, if the ethylene glycol plasma concentration does not account for the high osmolar gap, the pathology resident on-call is contacted. The resident will then investigate the case and contact the clinical service, if indicated. Elevated osmolar gaps may also be caused by methanol, isopropanol, propylene glycol, activated charcoal, mannitol, renal failure, and diabetic ketoacidosis, as well as by heavy ethanol consumption with high concentrations of ethanol metabolites (in some cases with little or no ethanol remaining) as may be seen in alcoholic ketoacidosis.
Availability: as needed.
Test
Limitations:
Icterus: No significant interference from bilirubin up to an I index of
60.
Lipemia: No significant interference from lipemia up to an L index of
500.
Hemolysis: >1,000 mg/dL will be canceled.
References:
(1) Young DS. Effects of Drugs on Clinical Laboratory Tests. 3rd ed.
Washington, DC: AACC Press; 1990.
(2) Young DS. Effects of Preanalytical Variables on Clinical Laboratory
Tests. Washington, DC: AACC Press; 1993: 3-120, 3-121.
Methodology:
Enzymatic (ethanol); freezing point depression osmometry (osmolality);
calculation (osmolality, calculated)
CPT Code:
82055
See Additional Information:
Chemistry Critical Lab Values
Osmolality Gap - Calculation and Interpretation
Osmolality Gap Calculator
Chemistry Critical Lab Values
Osmolality Gap - Calculation and Interpretation
Osmolality Gap Calculator