Module 8: Alcohols, Glycols

Question 1

Methanol, Ethanol, and Isopropanol are all alcohols by their structure; acetone is really a _____ by its structure

Answer 1

ketone

Question 2

What is present in grey top blood tubes?

Answer 2

1 % Sodium Fluoride (preservative) potassium oxalate (anti-coagulant)

Question 3

Type of elimination that Ethanol falls under

Answer 3

Zero-Order Elimination

-Constant amount eliminated per unit time
-Switches to first-order at smaller concentrations

0.015 - 0.020 g/100 mL/hr

Question 4

Where most EtOH is absorbed

Answer 4

Small Intestine

Question 5

How long does it take for most alcohol to be absorbed?

Answer 5

1 hour

Question 6

Approximate conversion for Serum to Blood EtOH concentration

Answer 6

1.2

Question 7

Volume of Distribution of EtOH for Men vs. Women

Answer 7

men = 0.68 L/kg
women = 0.55 L/kg

Question 8

True or False:
If doing a retrograde extrapolation must question if person is in absorption or elimination phase

Answer 8

True

-If person is still absorbing, the [EtOH] will be greater at time of blood sampling compared to actual OVI

Question 9

What is Henry’s Law?

Answer 9

relationship between concentration of dissolved gasses in a liquid to the concentration of the air above the liquid; concentration in lungs directly related to that in blood

Question 10

BAC : BrAC

Answer 10

2300:1

(shown as 2100:1 in these quizzes…)

Question 11

How is EtOH metabolized and eliminated by the body?

Answer 11

2-5% breath, urine, sweat

~0.1% Ethyl Glucuronide and Ethyl Sulfide

95% Oxidative metabolism via ADH

Question 12

Explain Oxidative Metabolism of EtOH.

Answer 12

3 ways:
1) EtOH + ADH –> Acetaldehyde; Acetaldehyde + ALDH –> Acetate
involves reducing NAD+ to NADH

2) Catalase

3) CYP2E1

Question 13

Where can alcohol dehydrogenase be found?

Answer 13

In cytosol of cells in liver and stomach

Question 14

Microsomal ethanol oxidizing system (MEOS)

Answer 14

CYP2E1

Found in microsomal fraction of liver hepatocytes

Question 15

This is inducible is a person is a chronic ethanol user

Answer 15

CYP2E1 Microsomal Ethanol Oxidizing System

This means alcoholics can concert ethanol faster; have faster elimination rates

Question 16

Accumulate of acetaldehyde is influenced by what four enzymes?

Answer 16

ADH, catalase, CYP2E1, ALDH

Question 17

2 Ethanol Biomarkers

Answer 17

Ethyl Glucuronide and Ethyl Sulfide

Question 18

What is ALDH?

Answer 18

Enzyme that converts Aldehyde to Acetate (in Ethanol metabolism)

Question 19

allele variation present in East Asians (~45%)

Answer 19

ALDH allele variation; means inactive ALDH2 enzymes

Question 20

Specimen to Blood Concentrations in post absorptive stage

Saliva, Spinal Fluid
Vitreous
Bile
Liver
Kidney
Brain
Urine

Answer 20

Saliva, Spinal Fluid 1.1
Vitreous 1.2
Bile 1.0
Liver 0.6
Kidney 0.7
Brain 0.8
Urine 1.3

Think: organs are slightly less; rest are slightly more

Serum = 1.2, Urine =1.3/1.4

Question 21

3 Types of Glycols

Answer 21

Ethylene Glycol (antifreeze, solvent)
Propylene Glycol (preservative, emollient in medications)
Diethylene Glycol (car things, solvent)

Question 22

Metabolic Pathway of Ethylene Glycol

Answer 22

Ethylene Glycol + ADH –> Glycoaldehyde
Glycoaldehyde + ALDH –> Glycolic Acid
(Glycolic Acid +GADH –> Glyoxazlic Acid)
(Glyoxalic Acid + GADH –> Oxalic Acid)
Oxalic Acid + Ca2+ –> Calcium Oxalate

Question 23

Stages of Toxicity for Ethylene Glycol

Answer 23

1) Neurological (appears innebriated, nausea, coma, convulsions)
2) Cardiopulmonary (tachypnea, tachycardia, hypertention, CHF, pulmonary edema)
3) Renal (flank pain, tubular necrosis)

Question 24

Treatment for Ethylene Glycol Poisoning

Answer 24

-Ethanol! It competes for ADH
-Enzyme will be busy metabolizing EtOH and Ethylene Glycol can’t break down into toxic metabolites
-Person can then undergo hemodialysis to clear Ethylene Glycol

Question 25

Methanol is primarily metabolized via alcohol dehydrogenase to:

Answer 25

Production of formaldehyde

(Methanol –>Formaldehyde –> Formic Acid)

Question 26

Significant hypocalcemia can occur with:
Ethanol toxicity
Acetone toxicity
Ethylene glycol toxicity
Methanol toxicity
Isopropanol toxicity

Answer 26

Ethylene glycol toxicity

Hypocalcemia means not enough; think about the pathway and formation of calcium oxalate

Question 27

Antidote for ethylene glycol poisoning:

Answer 27

Fomepizole

Question 28

These crystals are associated with ethylene glycol poisoning:

Answer 28

Calcium Oxalate

Question 29

The fermentation of glucose in blood to produce ethanol can be prevented by:

Answer 29

Sodium Fluoride (1%)

Question 30

Metabolite of Isopropanol

Answer 30

Acetone

Question 31

Methanol, Ethanol and Isopropanol. Rank in order from most toxic to least toxic:

Answer 31

Methanol, Isopropanol, Ethanol

Question 32

Ethylene glycol is metabolized by alcohol dehydrogenase to:

Answer 32

Glycoaldehyde

Question 33

A person experiencing ethylene glycol toxicity may show:
Deep and rapid breathing
Shallow and rapid breathing
Deep and slow breathing
Shallow and slow breathing

Answer 33

Deep and rapid breathing

Question 34

This substance is sometimes present in chronic alcoholics and malnourished individuals: Acetone

Answer 34

Acetone

Question 35

Fatal poisoning due to methanol is usually a result of:

Answer 35

Production of formic acid

Question 36

In the absorption phase, the blood alcohol concentration is 52 mg/dL. The vitreous alcohol concentration is expected to be ________ as compared to the blood alcohol concentration.

Lower, higher, or equivalent

Answer 36

Lower

*pay attention to absorption vs post absorption