Tox Exam 2 Common Household Products

Question 1

Ethylene glycol uses?

Answer 1

antifreeze, coolant, industrial solvent, rust remover, color film processing fluid, snow globes, hydraulic brake fluid, motor oil, windshield deicing agents

Question 2

Chemical properties of ethylene glycol?

Answer 2

soluble in water, sweet, colorless, odorless, lowers freezing point of water, rust inhibitor

Question 3

T/F Ethylene glycol poisoning is the most common cause of fatal poisoning in animals.

Answer 3

FALSE. Number 2 cause!

Question 4

What seasons are there more cases of ethylene glycol poisoning?

Answer 4

fall, winter, spring in NA

Question 5

What species have ethylene glycol poisoning been reported in?

Answer 5

cats, dogs, swine poultry

Question 6

What species has the lowest LD for ethylene glycol poisoning?

Answer 6

cats

Question 7

T/F There is increased absorption of ethylene glycol in the stomach if there is food present.

Answer 7

FALSE. delayed absorption due to food.

Question 8

Distribution of ethylene glycol?

Answer 8

ALL tissues, 1/2 life 11 hrs in dogs–shorter in cats

Question 9

Metabolism of ethylene glycol?

Answer 9

to TOXIC metabolites mainly in liver.
oxidized by alcohol dehydrogenase to glycoaldehyde–oxidized by aldehyde dehydrogenase to glycolic acid–oxidized by aldehyde dehydrogenase to glyoxylic acid–metabolized to oxalic acid, glycine, formic acid, hippuric acid & benzoic acid
oxalic acid binds to Ca–forms insoluble Ca oxalate cystals (monohydrate)

Question 10

Excretion of ethylene glycol?

Answer 10

small amount unchanged & Ca oxalate crystals in urine

Question 11

MOA of ethylene glycol toxicity?

Answer 11

ethylene glycol itself–>direct GI irritation, osmotic diuresis, CNS depression
toxic metabolites–>metabolic acidosis, ARF, CNS dysfunction

Question 12

MOA in CNS effects d/t ethylene glycol?

Answer 12

Glycoaldehyde causes CNS dysfunction by inhibition of respiration, glucose metabolism, serotonin metabolism & altered amine concentration.
Ca oxalate deposition contributes to CNS damage.

Question 13

MOA in metabolic acidosis d/t ethylene glycol?

Answer 13

mainly d/t glycolic acid

Question 14

MOA in acute renal failure d/t ethylene glycol?

Answer 14

Most metabolites are toxic to renal tube epi. Ca oxalate monohydrate crystals w/in tubules cause damage by altering cell structure/function–increasing ROS & mitochondrial dysfunction

Question 15

How many stages are involved in ethylene glycol poisoning?

Answer 15

2–early and late stages

stages are of shorter duration in kitty cats

Question 16

Describe early stage of ethylene glycol poisoning.

Answer 16

30 min-12 hr (d/t EG effects & metabolic acidosis)
nausea/V+, anorexia, CNS depression, ataxia, incoordination, hypothermia, muscle fasiculations, tachycardia, tachypnea, PU/PD, dehydration, coma, death
cats–markedly depressed & no PD signs

Question 17

Describe late stage of ethylene glycol poisoning.

Answer 17

24-72 hr in dogs & 12-24 hr in cats

V+, anorexia, depression, severe lethargy, coma, seizures, oliguria, renal pain, anuria (72-96 hr)

Question 18

Gross pathology of ethylene glycol poisoning?

Answer 18

hemorrhagic gastroenteritis, pulmonary edema, pale & swollen kidneys w/ gray or yellow streaks

Question 19

Micro pathology of ethylene glycol poisoning?

Answer 19

yellow rosette shaped Ca oxalate crystals in kidney, urine, perivascular space in brain

Question 20

Lab dx for ethylene glycol poisoning?

Answer 20

increased serum osmolality, increased anion gap, low USG, hypocalcemia, hyperglycemia, decreased blood pH

Question 21

Differential diagnosis for ethylene glycol poisoning?

Answer 21

toxin induced renal failure-->cholecalciferol, aminoglycosides, amphotericin B, cisplatin, NSAIDs, methoxyflurane, easter lily & day lily in cats.
infectious agents (lepto, pyelonephritis)
obstructive uropathy

Question 22

Treatment for ethylene glycol poisoning?

Answer 22

fomepizole, ethanol

MOA: competitively inhibit ADH (alcohol dehydrogenase)–inhibit formation of toxic metabolites

Question 23

T/F Can use activated charcoal with oral ethanol to treat ethylene glycol poisoning.

Answer 23

FALSE–do not use activated charcoal if using oral ethanol

Question 24

What can be given to enhance metabolism of glyoxylic acid to non-toxic metabolites?

Answer 24

thiamine & pyridoxine

Question 25

What can be given to treat acidosis related to ethylene glycol poisoning?

Answer 25

sodium bicarb

Question 26

What can be given to treat ARF related to ethylene glycol poisoning?

Answer 26

mannitol & hemodialysis

Question 27

T/F Ethanol has negative side effects that are not seen with fomepizole--CNS depression, diuresis & hyperosmolarity.

Answer 27

TRUE! but fomepizole can cause tachypnea, salivation, trembling. note: faster recovery with fomepizole.

Question 28

T/F Need higher doses of fomepizole in dogs than in cats to be effective.

Answer 28

FALSE. may need higher doses in cats!

Question 29

Prognosis in ethylene glycol poisoning?

Answer 29

once azotemic=prognosis is grave | early tx--dogs w/in 5-8 hrs & cats w/in 3 hrs=good prognosis

Question 30

Propylene glycol uses?

Answer 30

antifreeze, coolants, deicing, semi-moist pet food, treatment of bovine ketosis

Question 31

Propylene glycol chemical properties?

Answer 31

colorless, odorless, looks like mineral oil, miscible in alcohol & water, unpleasantly flavored

Question 32

Cause of accidental administration to horses?

Answer 32

accidentally given instead of mineral oil

Question 33

What species are susceptible to propylene glycol?

Answer 33

dogs, cats, cattle, horses

Question 34

What species are most susceptible to propylene glycol?

Answer 34

cats

Question 35

T/F Ethylene glycol is safer than propylene glycol.

Answer 35

FALSE

Question 36

What is the acute oral LD of propylene glycol in dogs?

Answer 36

9 ml/kg

Question 37

ADME of propylene glycol?

Answer 37

A=GI tract and inhalation M=in the liver by alcohol dehydrogenase to lactaldehyde--then metabolized by aldehyde dehydrogenase to lactic acid (D&L isomers)--then to pyruvic acid E=propylene glycol partly excreted unchanged in urine

Question 38

T/F Lactic acid & pyruvic acid are normal constituents of the citric acid cycle.

Answer 38

TRUE

Question 39

Difference between L-lactic acid & D-lactic acid?

Answer 39

L-lactic acid used by CAC & D-lactic acid not used readily--accumulates--increased concentrations may cause lactic acidosis

Question 40

T/F Propylene glycol is metabolized into non-toxic metabolites, while ethylene glycol is metabolized into toxic metabolites.

Answer 40

TRUE!

Question 41

Clinical signs of propylene glycol poisoning?

Answer 41

PU/PD (d/t osmotic diuresis), ataxia, CNS depression, heinz body anemia & muscle twitching in cats, D-lactic acid metabolite may cause encephalopathy & metabolic acidosis

Question 42

Treatment of propylene glycol poisoning?

Answer 42

emetics, activated charcoal, IV fluids, bicarb alcohol dehydrogenase inhibitors are not required vit C & E do not prevent heinz body formation

Question 43

Prognosis of propylene glycol poisoning?

Answer 43

Good!