April 2021: An Eye on the Problem

​A 3-year-old boy presented to the emergency department with lethargy. He was bradycardic and somnolent, responding only to physical stimuli. His vital signs were a temperature of 37°C, a heart rate of 50 bpm, a respiratory rate of 26 breaths per minute, a blood pressure of 92/41 mm Hg, and a pulse oximetry of 100% on room air.When awoken, the child answered questions appropriately but then fell back asleep quickly. His pupils were pinpoint. There were no signs of trauma. A cardiac examination demonstrated bradycardia, and the remainder of the examination was unremarkable.The child was given an IV fluid bolus and placed on a cardiac monitor. Labs were sent, including a CBC, BMP, LFTS, and urine drug screen. An ECG was done, remarkable only for bradycardia. A head CT was obtained, but all imaging and labs were unremarkable.What ingestions are in the differential?•    Clonidine•    Beta blockers•    Opioids•    Benzodiazepines•    Barbiturates•    PsychotropicsA thorough medication history was obtained, which included all potential medications available to the child in the household. Those were acetaminophen, ibuprofen, tetrahydrozoline optic (Visine), sertraline, Adderall, and liquid nicotine. A comprehensive toxicology panel was performed, and returned positive for tetrahydrozoline.What is the mechanism of action of tetrahydrozoline (THZ) hydrochloride?THZ is the active in...
Source: The Tox Cave - Category: Emergency Medicine Tags: Blog Posts Source Type: blogs