Test ID: VLTS
Volatile Screen, Serum
Useful For
Suggests clinical disorders or settings where the test may be helpful
Detection and quantitation of acetone, methanol, isopropanol, and ethanol in serum
Quantification of the concentration of ethanol in serum correlates with degree of intoxication
Evaluation of toxicity to the measured volatile substances
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Volatile substances in the blood include ethanol, methanol, isopropanol, and acetone:
-Ethanol is the single most important substance of abuse in the United States. It is the active agent in beer, wine, vodka, whiskey, rum, and other liquors.
-Methanol and isopropanol are highly toxic; toxicity results from ingestion (exogenous).
-Acetone is generally elevated in metabolic conditions such as diabetic ketoacidosis (endogenous). It also is a metabolite of isopropanol.
Ethanol acts on cerebral function as a depressant similar to general anesthetics. This depression causes most of the typical symptoms such as impaired thought, clouded judgment, and changed behavior. As the level of alcohol increases, the degree of impairment progressively increases.
On average, the serum or plasma concentration of the alcohols is 1.2-fold higher than blood concentration. For example, the serum or plasma would contain approximately 0.10 g/dL of ethanol in a blood specimen that contains 0.08 g/dL ethanol. Due to potential variations in the serum to whole blood ratio, serum should not be used in a medico-legal context. However, in the context of medical/clinical assessment, serum or plasma may be submitted for analysis.
Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
METHANOL
Not detected (Positive results are quantitated.)
Toxic concentration: > or =10 mg/dL
ETHANOL
Not detected (Positive results are quantitated.)
Toxic concentration: > or =400 mg/dL
ISOPROPANOL
Not detected (Positive results are quantitated.)
Toxic concentration: > or =10 mg/dL
ACETONE
Not detected (Positive results are quantitated.)
Toxic concentration: > or =10 mg/dL
Interpretation
Provides information to assist in interpretation of the test results
Toxic concentrations:
-Methanol: > or =10 mg/dL
-Ethanol: > or =400 mg/dL
-Isopropanol: > or =10 mg/dL
-Acetone: > or =10 mg/dL
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
No significant cautionary statements
Clinical Reference
Provides recommendations for further in-depth reading of a clinical nature
1. Caplan YH: In Forensic Science Handbook. Vol 1. Edited by R Saferstein. Englewood Cliffs, Prentice Hall, 1982
2. Goodman and Gilman's: The Pharmacological Basis of Therapeutics. Seventh edition. Edited by TW Rall, F Murad. New York, McMillan Publishing, 1985
3. Porter WF, Moyer TP: Clinical toxicology. In Tietz Textbook of Clinical Chemistry. Fourth edition. Edited by CA Burtis, ER Ashwood. Philadelphia, WB Saunders Company, 1993, pp 1155-1235
4. Principles of Forensic Toxicology. Edited by B Levine. Washington DC, American Association of Clinical Chemistry, 1999


