8.8 A) Alcohols Toxicology

Front 1

Which is incorrect regarding the osmolar gap?
A. Osmolality = 2 x Na + urea + glucose + ethanol
B. A normal osmolar gap does not exclude toxic alcohol poisoning
C. The osmolar gap measures additional osmotically active molecules in the serum.

D. Non toxicological medical conditions do not cause an increased

Osmolar gap.

Back 1

D. They can, and do.

Front 2

Formula for calculated osmolality?

Back 2

2 x Na + urea + glucose + ethanol

in mOsm/kg

Front 3

Which is incorrect regarding ethylene glycol

ingestion?
A. Ingestion of > 0.5 mL/kg is potentially lethal
B. Unintentional ingestion of less than a mouthful is benign.

C. The co-ingestion of ethanol complicates the risk assessment.
D. The toxic effects are not due to the parent compound - but rather the metabolites.

Back 3

A. Ingestion of > 1mL/kg of ethylene glycol is

potentially lethal.

Front 4

Which is incorrect regarding ethylene glycol

ingestion?
A. A severe anion gap metabolic acidosis develops. (HAGMA)

B. The toxicity is from the accumulation of glycolic acid, lactate, and

calcium oxalate.

C. Hypercalcaemia develops.
D. Calcium oxalate crystals form in many tissues [ renal tubules ;

myocardium ; muscle and brain ]

Back 4

C. Hypocalcaemia

Front 5

Which is incorrect regarding the toxicokinetics of ethylene glycol?
A. Peak concentrations occur within 1-4 hours
B. It is metabolised sequentially to glycolic acid and glycoaldehyde.
C.It is metabolized by ADH [alcohol dehydrogenase ] and ALDH

[aldehyde dehydrogenase]

D. ADH inhibition occurs by ethanol or fomepizole

Back 5

B. glycoaldehyde first , then glycolic acid

Front 6

How many stages are there to ethylene glycol

intoxication, and what are they?

Back 6

3 Stages of intoxication:

1. CNS
2. Cardiopulmonary
3. Renal

Front 7

Which is incorrect regarding the Clinical

features of ethylene glycol intoxication?
A. Flank pain and oliguria indicate acute renal failure
B. Cranial neuropathies occur early
C. Progressive features : tachypnoea , tachycardia, hypertension,

decreased consciousness, shock, coma, seizures, death.
D. The initial clinical features are similar to ethanol intoxication.

Back 7

B. Cranial neuropathies are Late features :

5-20 days

Front 8

List the serum surrogate markers of ethylene glycol intoxication - toxicity.

[ from blood gas and serum electrolytes]

Back 8

1. Elevated osmolar gap
2. Anion gap metabolic acidosis- HAGMA
3. hyperlactatemia
plus
4. hypocalcaemia
5. rising creatinine.

Front 9

Which is incorrect regarding ethylene glycol

ingestion?
A. the absence of calcium oxalate crystals in the urine excludes

intoxication with ethylene glycol.
B. Sodium bicarbonate can be given in severe acidaemia : 1-2 mmol/kg IV
C. Hypocalcaemia is ONLY CORRECTED with prolonged QT or

refractory seizures.
D. Haemodialysis is the definitive management of EG intoxication.

Back 9

A. Its presence is pathognomonic, but its

absence does not exclude toxicity.

Front 10

Indications for Haemodialysis in Ethylene

Glycol intoxication? [ 3 ]

Back 10

1. Hx of large EG ingestion, with

osmolar gap > 10
2. Acidaemia : pH < 7.25
3. Acute renal failure

Front 11

Sources of ethylene glycol?

Back 11

1. Radiator coolants
2. Solvents
3. Brake fluids
4. De - icing solutions

Front 12

Which is incorrect regarding the pitfalls of

ethylene glycol (EG) ingestion?
A. The absence of symptoms does not exclude a significant ingestion
B. A normal osmolar gap excludes significant intoxication

C. In the presence of ethanol, a normal serum bicarbonate does not

exclude significant ingestion

D. Co-ingestion of ethanol DELAYS the onset of clinical features of EG

intoxication.

Back 12

B. It doesn't.

Front 13

Which is incorrect regarding Methanol

poisoning?
A. The methanol compound on its own is non-toxic.

B. The metabolites of Formaldehyde and Formic acid depend on

conversion of methanol via ALDH - aldehyde dehydrogenase.
C. Ethanol and Fomepizole saturate alcohol dehydrogenase (ADH).

D. Haemodialysis is the definitive Management.

Back 13

B. ADH = alcohol dehydrogenase

Front 14

What are the Treatment options for Methanol poisoning ?

Back 14

1. Haemodialysis (Definitive Mx)
2. Ethanol
3. Fomepizole { Not available in Australia }
4. Folinic acid 2mg/kg IV q6H
5. NaHCO3 (for pH < 7.3)

Front 15

Which of the following is not an indication for Haemodialysis in methanol poisoning ?

A. Visual symptoms
B. pH 7.3
C. Renal Failure
D. Deteriorating Vital signs - Electrolytes.

Back 15

B. pH < 7.3

Front 16

What is the Pathway for methanol

metabolism ?

Back 16

Methanol --> Formaldehyde--> Formic acid-->

CO2 + H2O

[ ADH --> ALDH --> Folate ]

Front 17

List the Symptoms and Signs of Methanol

poisoning.

Back 17

GIT
1. Nausea and vomiting
2. Abdominal pain
CNS
1. Headache
2. Confusion- ACS
Ocular Toxicity
1. Decreased VA
2. Retinal oedema - hyperaemic optic disc

Front 18

In regards to ethylene glycol poisoning, which is incorrect?
A. Symptoms can present sooner with concurrent ethanol intoxication.
B. Osmolar Gap > 10 is an indication for haemodialysis.
C. It can give rise to Prolonged QT and seizures.
D. Ethanol and Fomepizole are used in suspected ingestions awaiting Haemodialysis.

Back 18

A. Symptoms are delayed with concurrent ethanol ingestion - can be up to 6-12 hours.

Front 19

Which is incorrect regarding the Competitive

inhibitors of Alcohol dehydrogenase?
A. Fomepizole ( 4-MP) is easier to use than ethanol for the treatment of methanol / ethylene glycol poisoning.
B. Fomepizole is available in Australia, but not New Zealand.
C. Ethanol can cause hypoglycaemia and respiratory depression.
D. Their indication for use is "suspected ingestion" whilst awaiting Haemodilaysis ( Large, known ingestion ; pH < 7.3 ; ARF )

Back 19

B. Fomepizole is Not available in Australia.

Front 20

Which is correctcregarding Toxic alcohol

poisoning?
A. Ethylene glycol gives visual symptoms and direct retinal toxicity.

B. A normal osmolar gap excludes toxic levels of the toxic alcohols.
C. A negative UV light flourescence test of the mouth and urine for

ethylene glycol (antifreeze) excludes ingestion.
D. Death can occur with as little as 2 tablespoons of methanol- the

minimal lethal dose for EG is 1-2 mL/kg

Back 20

D.

A = Methanol = retinal toxicity
B = A normal Osmolar Gap does not exclude toxic levels of Methanol / EG
C = A negative test misses 2/3 ingestions