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1416 Ethylene Glycol Intoxication

Ethylene Glycol Intoxication
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Observed or suspected exposure to
antifreeze (ethylene glycol [EG])

• Physical examination (see Ethylene Glycol
Intoxication, p. 314)
• Review detailed exposure history
• Distinguish EG (i.e., “regular” antifreeze) from
propylene glycol (i.e., “safe” or “safer” antifreeze)
and windshield washer fluid for prognosis and
treatment decisions

Is a history of ingestion confirmed?
Is there a strong suspicion of ingestion?

No Yes

Diagnostic testing: proceed with ruling out EG Decontaminate patient if exposure
toxicity as clinically appropriate occurred within 30 to 60 minutes
• Consider emetic and activated charcoal
Confirmatory Ancillary • Reminder: Collect blood for diagnostic
testing before administering charcoal,
(1) Measure serum EG, glycolic acid Serum osmolality, osmolal gap which contains propylene glycol that
levels: critical/urgent • Osmolality rise parallels blood EG will result in a false-positive result
• EG is measurable within 60 levels
minutes of ingestion • Note elevation within 1 hour of
• Rapidly access a human hospital ingestion (rapid, indirect evidence Administer intravenous crystalloids at a
or other diagnostic laboratory of toxicosis) moderate to high rate
OR • Correct dehydration and hypotension
(2) Evaluate using veterinary serum EG • Avoid overload; monitor fluid input and
test kit. Options: Anion gap urine output
• Kacey EG diagnostic strips • Can begin to rise within 3 hours of
(Kacey Inc., Asheville, NC; phone: ingestion but is more apparent by
828-685-3569). Quantitative test, 6 hours Antagonize EG metabolism with
dogs and cats. Sensitivity = • Is too late to trigger treatment fomepizole (4-methylpyrazole [4-MP]) or
50 mg/dL (dogs), 20 mg/dL (cats). decision in the cat ethanol (p. 314)
Test time = 8 minutes. Positive for
any alcohol (ethanol, methanol,
propylene glycol, xylitol, etc.) Urinalysis: Calcium oxalate mono- Monitor acid-base status during treatment
• VetSpec (Catachem ethylene glycol hydrate crystalluria • Correct acidosis as needed with
test; Catachem Inc., Oxford, CT; • Is notable within 4 to 6 hours of sodium bicarbonate
phone: 203-262-0330). Qualitative ingestion in dogs • Avoidance of acidosis is very important
test, dogs and cats. Sensitivity = • Is notable within 3 hours of ingestion to offset metabolite damage
50 mg/dL (dogs), 20 mg/dL (cats). in cats but is too late for successful
Test time = 5 minutes. Positive for treatment
any cis-1-diol (propylene glycol, Dialysis
glycerol, sorbitol) • Begin peritoneal dialysis or hemodialysis
Serum chemistry profile at presentation if azotemia is present
Negative Positive • Measures serum creatinine and • Avoidance of acidosis: a very effective
blood urea nitrogen levels; is useful approach when available
for monitoring patient status but
• No toxicosis Begin treatment rises too late (approximately 12 hours)
• Less than 60 for antidote in dogs and cats
minutes since Monitor renal function q 8-12h for the first
ingestion 72 hours as needed
• False-negative
result (rare) Improved/normal Poor/worse

Periodically monitor Provide supportive
for long-term effects care or euthanize
UPDATED AND EDITED BY: Leah A. Cohn, DVM, PhD, DACVIM
ORIGINALLY WRITTEN BY: Michael W. Knight, DVM, DABVT, DABT
www.ExpertConsult.com