543: Fatal Toxic Exposure: Fentanyl, “Dust-Off,” or Both?

Introduction: Toxic inhalant exposure is an often-overlooked cause of acute intoxication, frequently mistaken for opioid overdose. “Dust-Off” (difluoroethane), a common electronics cleaner, is widely misused for its euphoric effects and can cause hypoxia, arrhythmias, and sudden death. Given overlapping features with opioid toxicity, especially in polysubstance users, this case underscores the importance of considering inhalants in the differential diagnosis of drug-related cardiac arrest. Description: A 32-year-old female with IVDU and polysubstance abuse (methamphetamine, opioids, inhalants) was found unresponsive after unknown downtime. EMS identified PEA arrest; CPR, two rounds of epinephrine, and 6 mg naloxone were given, achieving ROSC. She was intubated in the field and transported to the ED, where she was comatose with absent brainstem reflexes and required vasopressors. Labs showed high anion gap metabolic acidosis, markedly elevated lactate, hyperglycemia, AKI, and transaminitis. Urine tox screen was negative (fentanyl not included), raising concern for non-opioid toxicity. Imaging revealed severe anoxic brain injury, EEG showed diffuse cortical suppression; MRI confirmed global injury. Given her inhalant use and negative opioid screen, alternative toxidromes were considered, though management was already appropriate. Brain death was confirmed after 72 hours without neurological improvement. Discussion: Consumer aerosol products like “Dust-Off” are often misused for their psychoactive effects but pose serious risks, including sudden sniffing death. Difluoroethane, a fluorinated hydrocarbon, sensitizes the myocardium to catecholamines, increasing the risk of fatal arrhythmias—even without other signs of intoxication—making diagnosis challenging. Standard urine toxicology does not detect inhalants, requiring high clinical suspicion and thorough history. Unlike fentanyl, difluoroethane is unresponsive to naloxone, and no antidote exists; management is entirely supportive. In young patients with substance use and unexplained cardiac arrest, inhalant toxicity should be considered. Early recognition is critical due to rapid onset and risk of irreversible hypoxic injury. Greater awareness is needed, as these agents are widely available, frequently abused, and often overlooked.