Alcohol Metabolism & Physiology Flashcards

During the absorptive phase of alcohol pharmacokinetics, breath alcohol readings may differ from venous BAC because:

Answer: Arterial blood (equilibrated with alveolar air) may be higher than venous blood before distribution is complete

During absorption, arterial blood BAC exceeds venous BAC; since breath reflects arterial concentration, BrAC can be higher than venous BAC until equilibrium is reached.

Which of the following factors would be expected to DECREASE the peak BAC achieved after consuming a fixed dose of alcohol?

Answer: Consuming a high-fat meal before drinking

A high-fat meal slows gastric emptying significantly, delaying absorption and reducing the peak BAC compared to drinking on an empty stomach.

A BAT observes that a subject has diabetes with ketoacidosis. The primary concern for the breath test result is:

Answer: Elevated ketone bodies (especially acetone) may produce a falsely elevated BrAC on some instruments

Ketoacidosis elevates endogenous acetone levels in breath, which can be misidentified as ethanol by some breath testing technologies, particularly non-selective IR devices.

The concept of 'slope detector' or 'rising breath alcohol' check in modern evidential instruments is designed to detect:

Answer: Mouth alcohol contamination, which causes a higher initial reading that drops as the sample progresses

Mouth alcohol causes a concentration gradient that is highest at the beginning of the breath sample; a slope detector identifies this declining pattern to flag potential contamination.

Hepatic encephalopathy in severe alcoholic liver disease is most directly caused by impaired metabolism of:

Answer: Ammonia

Ammonia normally detoxified by the liver to urea accumulates in liver failure and crosses the blood-brain barrier, causing hepatic encephalopathy.

Which statement correctly describes the relationship between alcohol concentration in urine and blood?

Answer: Urine alcohol concentration typically averages about 1.3 times the blood alcohol concentration

The average urine-to-blood alcohol ratio is approximately 1.3:1, reflecting urine's higher water content compared to whole blood.

Hyperventilation immediately before a breath test would most likely result in a BrAC reading that is:

Answer: Falsely decreased because rapid breathing washes alcohol out of alveolar air

Hyperventilation can reduce BrAC readings by 10-20% by washing CO2 and alcohol vapor out of the lungs before the test sample is collected.