Ethylene Glycol Ingestion
ABSTRACT:
Audience:
This scenario was developed to educate emergency medicine residents on the diagnosis and management of ethylene glycol ingestion. This case is also appropriate for senior medical students and advanced practice providers. The principles of crisis resource management, teamwork, and communication are incorporated into the case.
Introduction:
Ethylene glycol is a component of antifreeze and engine coolant, and its ingestion is much less common than ethanol intoxication. Poison control centers have reported between 4000 and 6000 cases of ethylene glycol exposures per year.1 Nonspecific symptoms such as depressed mental status with ingestion of either substance may lead providers to misdiagnose ethylene glycol for ethanol intoxication unless a high level of suspicion is maintained, and the morbidity of ethylene glycol ingestion is significant, with more than 6,000 exposures and 22 deaths in the US in 1998.1 It has been reported that 18.1% of ethylene glycol exposures died when treated with ethanol, while 4.1% died when treated with fomepizole.2 While ethylene glycol is not directly toxic to the body, it has toxic metabolites, including the nephrotoxic oxalic acid. However, with proper medical intervention, many of its toxic effects can be prevented.
Affected individuals may suffer from end-organ dysfunction, particularly renal failure, and subsequent death without proper intervention. Laboratory hallmarks that support the diagnosis of ethylene glycol ingestion include an increased osmolar gap, calcium oxalate crystals on urinalysis (UA), and renal dysfunction.2 A patient’s urine may also fluoresce under black light due to the addition of fluorescein to ethylene glycol (although this finding is not sensitive or specific).
Typical interventions for ethylene glycol toxicity include fomepizole administration and evaluation for hemodialysis, particularly if a patient has acidemia or end-organ dysfunction. Other toxic alcohols include methanol (which may be found in cologne and windshield washer fluid) and isopropyl alcohol (or rubbing alcohol). Methanol typically presents similarly to ethylene glycol with nonspecific intoxication symptoms, but with the additional symptoms of vision changes or blindness. Isopropyl alcohol presents with gastric irritation and ketosis without acidosis. Treatment of methanol ingestion is similar to ethylene glycol, while treatment of isopropyl alcohol ingestion is generally supportive.2
This simulation scenario allows learners to reinforce their ethylene glycol ingestion management skills in a psychologically-safe learning environment, and then to receive formative feedback on their performance.
Objectives:
By the conclusion of the simulation session, learners will be able to: 1) obtain a thorough toxicologic history, including intent, timing, volume/amount, and assessment for co-ingestions, 2) distinguish the variable clinical signs and symptoms associated with toxic alcohol ingestions, 3) identify metabolic derangements associated with toxic alcohol ingestions, 4) discuss the management of toxic alcohol ingestion, 5) appropriately disposition the patient for admission to intensive care unit (ICU).
Method:
This simulation was written for a high-fidelity simulator, followed by a debriefing session and lecture on the diagnosis and management of ethylene glycol ingestion. However, it could be run with a low- or moderate-fidelity simulator or as an oral boards case. Debriefing methods may be left to the discretion of participants, but the authors have utilized advocacy-inquiry techniques.
Topics:
Medical simulation, ethylene glycol ingestion, toxic alcohol ingestion, toxicology.