Unit 3 - Hazards at Home

Question 1

What resources are available for home hazard intoxication situations?

Answer 1

Pet poison helpline

Poison control center

ASPCA National Poison Control center

Toxnet.nlm.nih.gov

Question 2

What are the characteristics of ethylene glycol?

Answer 2

Clear

Sweet taste

Odorless

Question 3

What are the sources of ethylene glycol toxicity?

Answer 3

Antifreeze

Automobile fluids - brake, hydraulic, transmission

Question 4

When do ethylene glycol toxicosis cases typically occur?

Answer 4

Fall & winter

Question 5

What species are susceptible to ethylene glycol toxicosis? Most commonly affected?

Answer 5

All species are susceptible

Dogs and cats most commonly affected

Question 6

What are the common causes of ethylene glycol poisoning?

Answer 6

Chewed bottles, spills, wrong drench used

Question 7

Rank the three types of antifreeze from highest ethylene glycol concentration to lowest.

Answer 7

Permanent (95%) > Diluted (50%) > Propylene glycol (0%)

Question 8

Where is ethylene glycol absorbed? Metabolized? Excreted?

Answer 8

Absorbed in the GI tract

Metabolized in the liver and kidneys (2-4 hours)

Excretion in the urine(24-48 hours)

Question 9

What is the MOA of ethylene glycol toxicosis?

Answer 9

1. Ethylene glycol metabolized by alchohol dehydrogenase
2. Glycoaldehyde metabolized by aldehyde dehydrogenase
3. Glycolic acid metabolized by lactic dehydrogenase
4. Acidosis occurs
5. Oxalic acid binds Ca
6. CaOxalate crystal deposition
7. Renal necrosis & death

Question 10

How many stages are there of clinical signs associated with ethylene glycol toxicosis?

Answer 10

3 stages

Question 11

What is the first stage of clinical signs due to ethylene glycol? When does it occur?

Answer 11

Stage 1 (0.5-12hrs)

Drunken animal: vomiting, depression, PU/PD, & ataxia

Question 12

What clinical signs occur during stage 2 of ethylene glycol toxicosis? When does it happen?

Answer 12

Stage 2 (12-72 hrs):

Severe acidosis - tachypnea, vomiting, depression/comatose, bradycardia, miosis, seizures

Question 13

What clinical signs occur during stage 3 of ethylene glycol toxicosis? When does it happen?

Answer 13

Stage 3 (72+ hrs):

Renal failure: Oliguria → anuria, oral ulcerations, convulsions, death

Question 14

T/F: Ethylene glycol toxicity may go unnoticed until later stages.

Answer 14

True - you may see overlaping of stages

Question 15

What antemortem samples can be taken for diagnosis of ethylene glycol toxicosis? What is done with these samples?

Answer 15

Serum & urine - both for ethylene glycol detection and clinical pathology

Question 16

What post mortem samples can be taken for diagnosis of ethylene glycol toxicosis? What is done with the samples?

Answer 16

Kidney - ethylene glycol, histopath (diagnostic on its own)

Rumen content - ethylene glycol

Ocular fluid - Glycolic acid

Question 17

What CBC abnormalities are associated with ethylene glycol toxicity?

Answer 17

Dehydration, ↑ PCV, ↑ Protein, stress leukogram

Question 18

What serum chemistry abnormalities are associated with ethylene glycol toxicosis?

Answer 18

Acidosis (large anion gap)
Azotemia -↑ BUN, ↑ Creatinine
Mineral concentrations - ↑Phosphorus, ↑Potassium, ↓Calcium

Question 19

What urinalysis results are consistent with ethylene glycol toxicosis?

Answer 19

pH of <6.5

Calcium oxalate crystalluria

Question 20

What tool can be used to detect ethylene glycol in serum?

Answer 20

The ethylene glycol test kit - it is qualitative but an analytical lab is required for it to be quantitative

Question 21

What gross lesions are associated with ethylene glycol toxicosis?

Answer 21

Sweet odor of oral cavity & GI tract
Kidneys - pale, firm/congestion, +/- pale streaks

Question 22

What microscopic lesions are consistent with ethylene glycol toxicosis?

Answer 22

Renal tubular necrosis

Oxalate crystal deposition

Question 23

How is ethylene glycol toxicosis treated?

Answer 23

Decontamination and IV fluids - AC w/in 2 hours of consumption

Prevent metabolism of EG - 7% ethanol IV or 20% ethanol IV

Antidote

Question 24

What is the antidote for ethylene glycol toxicosis? How does it work?

Answer 24

4-Methylpyrazole - it, along with the use of ethanol, competitively inhibits alcohol dehydrogenase by binding to it

Question 25

What side effects are associated with using ethanol for the treatment of ethylene glycol toxicosis? Pros to using it?

Answer 25

Side effects - respiratory depressant and CNS depressane (can cause ethanol poisoning) Cheap

Question 26

What are the pros and cons of using 4-MP for the treatment of ethylene glycol toxicosis?

Answer 26

Safer but more expensive

Question 27

What are the caveats to using either ethanol or 4-MP for the treatment of ethylene glycol toxicosis?

Answer 27

They must be given ASAP - once ethylene glycol has been metabolized there is no effect They MUST NOT be given together

Question 28

What are the methylxanthines that are of concern with toxicosis in animals?

Answer 28

Caffeine, Theobromine, theophylline

Question 29

What are the sources of caffeine for toxicosis?

Answer 29

OTC stimulants, coffee beans, regular coffee, decaf coffee, soft drinks, **chocolate**

Question 30

What are the sources of theobromine toxicosis?

Answer 30

Cacao beans, unsweetened baking chocolate, cocoa powder, **chocolate** (dark \> milk \> white), cacao bean mulch

Question 31

What are the sources of theophylline toxicosis?

Answer 31

Tea, human asthma medication, various foods and beverages

Question 32

What is the toxic dose of theobromine in dogs and cats?

Answer 32

Dog - 250-500 mg/kg Cats - 200 mg/kg

Question 33

What are the toxic doses of caffeine in dogs and cats?

Answer 33

Dog - 110-200 mg/kg Cat - 80-150 mg/kg

Question 34

Why do chocolate compounds pose an increased risk of methylxanthine toxicosis?

Answer 34

Because they contain both caffeine and theobromine

Question 35

Where are the methylxanthines absorbed? Distributed? Excreted?

Answer 35

I assume GI tract.....Rapid absorption (theophylline has decreased absorption with food) Wide distribution - can cross the placenta Excretion - urine, bile, milk

Question 36

What are the MOAs of methylxanthines (there are multiple)?

Answer 36

1. Competetive antagonist of adenosine → bronchodilation, tachycardia, vasoconstriction, CNS stimulation 2. ↑ Intracellular calcium 3. Inhibition of phosphodiesterase → ↑ cAMP → ↑ Release of catecholamines 4. Stimulation of sympathetic nervous system

Question 37

What clinical signs are associated with methylxanthine toxicosis?

Answer 37

**CNS**: Hyperactivity, Agitation, Seizures **Cardiac:** Tachycardia (200- 300 bpm), Arrhythmias **Elevated motor activity**: Hyperexcitability, Tremors, Polyuria **GI irritation:** Vomiting, Diarrhea

Question 38

What lesions are associated with methylxanthine toxicosis?

Answer 38

No specific lesions, but you should evaluate the oral cavity for the presence or odor of chocolate

Question 39

How is methylxanthine toxicosis diagnosed?

Answer 39

Detection of methylxanthine alkaloid - serum, plasma, urine, GI content, milk

Question 40

How is methylxanthine toxicosis treated?

Answer 40

**ABCs:** Artificial respiration Control seizures - Diazepam Control arrhythmias - lidocaine (dogs), propranolol (cats) ↓ BP - Metoprolol, propranolol Decontamination - emesis, gastric lavage, activated charcoal