Effects of pretest breathing maneuvers on the single breath ethanol profile

Pretest breathing maneuvers change the "axial profile of alcohol content in the mucous lining the airways" (George, Ann Biomed Eng, 23:48-60, 1994). We quantified the relative changes in a subject's exhaled ethanol profile following pretest breathing maneuvers in order to validate a predictive mathematical model. Human subjects were administered liquor in a dose appropriate to reach a blood level of approximately 0.10g/100mL. The subjects then performed a series of three breathing maneuvers: hyperventilation, hypoventilation, and breath holding. Breath ethanol and CO₂ concentrations were measured at a constant flow rate using a mass spectrometer. Preliminary results support the model's prediction of an increase in the Phase III slope of the exhaled ethanol concentration following hyperventilation vs. control and an increase in the endpoint ethanol concentration following hypoventilation. These results suggest that: 1) the model's predictive capabilities are sound and 2) a more reliable method of measuring exhaled ethanol may be needed.