DISPOSITION

..... Admission

All patients with hemodynamic abnormalities, persistent

mental status changes, and metabolic or acid-base

irregularities should be admitted to an intensive care

setting. Additionally, those who ingested medications that

either require antidotal therapy or have prolonged or

delayed toxic effects ( eg, sulfonylureas, extended-release

calcium channel blockers, or beta-blockers) also require

admission to a critical care setting. All suicidal patients will

require psychiatric consultation for clearance.

CHAPTER 54

..... Discharge

Patients with accidental ingestions of innocuous substances,

those with no evidence of acute toxicity, and those who

have no potential for delayed detrimental effects can be

discharged.

SUGGESTED READING

Barry JD. Diagnosis and management of the poisoned child.

Pediatr Ann. 2005;34:937-946.

Erickson TB, Thompson TM, Lu JJ. The approach to the patient

with the unknown overdose. Emerg Med Clin North Am.

2007;25:249-28 1.

Hack JB, Hoffman RS. General management of poisoned

patients. In: Tintinalli JE, Cline DM, Cydukla RK, et al., eds.

Tintinalli's Emergency Medicine: A Comprehensive Study

Guide. 7th ed. New York, NY: McGraw Hill, 201 1:11 87-1 193.

Toxic Alcohols

Ma rk B. Mycyk, MD

Key Points

• Consider toxic alcohol poisoning in cases of an

unexplained anion gap acidosis or an elevated osmol

gap.

• Focus your initial treatment on the early inh ibition of

alcohol dehydrogenase (ADH) in cases of ethylene

glycol or metha nol poisoning to prevent the

accumulation of toxic metabol ites.

INTRODUCTION

With the exception of ethanol, no other alcohols are safe

for human consumption and are therefore considered

toxic alcohols. Ethylene glycol, methanol, and isopropanol

are the most common toxic alcohols associated with

human poisoning. Toxic alcohols are often ingested in 1 of

2 ways, either unintentionally if placed in an inappropriately labeled container, or intentionally by patients either

attempting suicide or trying to become intoxicated when

regular ethanol is not readily available. Of note, each of the

3 is capable of causing inebriation, with isopropanol being

twice as intoxicating as ethanol.

According to the National Poison Data System, more

than 35,000 toxic alcohol exposures are reported to the

American Association of Poison Control Centers yearly.

Isopropanol is the most frequently ingested but causes the

fewest number of deaths, whereas methanol is the least

commonly ingested toxic alcohol but associated with the

highest number of fatalities.

Although the parent compound is responsible for

inebriation, toxicity results from the metabolism of these

compounds via alcohol dehydrogenase (ADH) into toxic

organic acid byproducts with consequent end organ injury.

Ethylene glycol is metabolized to glycolic acid, glyoxylic

• Consult your local poison center (800-222-1 222) or local

toxicologist in all suspected cases for help initiating

antidota l therapy and obtaining confirmatory toxic

alcohol levels.

• Consult a nephrolog ist early to prepare for hemodia lysis

in cases involving large ingestions or severe metabolic

acidosis.

acid, and oxalic acid, all of which can produce systemic

acidosis and acute kidney injury. Methanol is converted to

formic acid which can produce systemic acidosis and

retinal toxicity. Isopropanol is not converted to an organic

acid but is rather metabolized into acetone, which can

produce hemorrhagic gastritis and systemic hypotension

in the absence of a concurrent acidosis. If either are

unrecognized or untreated, all toxic alcohol ingestions can

result in patient fatality.

CLINICAL PRESENTATION

..... History

Obtaining a history of toxic alcohol ingestion is often

challenging. Patients may be obtunded on arrival to the

emergency department (ED), not forthcoming with the

ingestion history, or too young to be appropriately

descriptive (children). Reading the ingredient lists on the

labels of any empty bottles found at the scene or brought

to the ED can be extremely helpful. If a bottle or label is not

available, ask the patient what kind of product was

ingested. For example, antifreeze usually contains ethylene

glycol, windshield-washing fluid usually contains methanol, and rubbing alcohol usually contains isopropanol.

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That said, remember that some products may contain different types of toxic alcohols ( eg, some gas-line antifreeze

products contain methanol). Beyond attempting to identify exactly what was ingested, it is critically important to

determine the time of ingestion, as this will affect the

interpretation of laboratory results and impact patient

management priorities.

..... Physical Examination

Most patients poisoned with a toxic alcohol will

demonstrate some level of central nervous system (CNS)

depression analogous to inebriation. Patients arriving

soon after an ingestion may appear well with unremarkable physical exams, whereas those who arrive many hours

after ingestion may be obtunded with unstable vital signs.

Of note, the peak serum level of a toxic alcohol correlates

poorly with the physical exam findings. As with all

overdoses, perform a careful neurologic examination

(mental status, cranial nerves, cerebellar findings, and

motor strength).