A Case of Opioid Overdose? Or Is It?

A 28-year-old man was found unresponsive at home by a roommate. When emergency medical services (EMS) arrived, he was found to have miosis and was cyanotic with respiratory depression. He was unresponsive to intranasal naloxone (2 mg) that was administered via mucosal atomizer twice. On admission to the emergency department, the patient had a systolic blood pressure of 95 mmHg, a diastolic blood pressure of 70, oxygen saturation was 84% on 100% nonrebreather mask, and respiration rate was 10 breaths/min. Physical examination showed pinpoint pupils. Per the roommate, this patient had been in a car accident a year prior and had been prescribed hydrocodone. After becoming addicted to hydrocodone, he was known to buy street drugs. His roommate explained that the previous night, he bought Norco® (hydrocodone and acetaminophen) from a drug dealer. A urine drugs of abuse screening panel was ordered, which included amphetamines, barbiturates, benzodiazepines, cocaine metabolite (benzoylecgonine), opiates, and tetrahydrocannabinol (THC) and was negative. The serum acetaminophen concentration obtained upon admission was <10 ug/mL. Because the patient's history and physical were consistent with an opioid toxidrome, the clinician gave intravenous naloxone (0.4 mg) and the patient woke up. The clinician called the laboratory for a toxicology consultation. He asked if there were any send-out tests that would detect …