Dermatitis

Carbon Monoxide Poisoning: Clues to Unmasking the Great Masquerader

By SAIMA TABARAK QURESHI, MD PRASHANT MAHAJAN, MD, MPH, MBA

 

A 14-year-old boy was brought to the emergency department (ED) by paramedics after he complained of dizziness and an episode of falling down early that morning when he awoke to go to the bathroom. His mother experienced a similar sensation of dizziness when she awoke to the sound of her son’s fall. Paramedics reported that the boy had to be carried out of the house because of his unsteady gait and depressed mental status. He received oxygen by mask during the 20 minutes of transport time in the ambulance.

In the ED, the patient was alert, comfortable, and well-oriented. Further inquiry revealed that he had been complaining of dizziness and palpitations for the past 3 days. His mother reported that he had been evaluated by his pediatrician on the previous day and had received a diagnosis of “flu.”

His vital signs were stable, and he had an oxygen saturation of 97% while breathing room air. Results of the clinical examination were otherwise unremarkable. Capillary blood gas analysis by co-oximetry showed a pH of 7.4 and a partial pressure of carbon dioxide of 35.1 mm Hg. The carboxyhemoglobin (COHb) level was 16.4%. Carbon monoxide (CO) poisoning secondary to use of a propane heater was the diagnosis.

As the weather gets colder, this case scenario takes on particular importance. First, it serves as a reminder that most CO exposures occur during the winter, when use of indoor heating devices increases. Second, it underscores the potential difficulty in recognizing CO poisoning. CO poisonings typically coincide with the influenza season. Symptoms— which include dizziness, headache, drowsiness, and loss of consciousness— may also mimic those of the flu, food poisoning, gastroenteritis, or colic. Parents often seek the care of a pediatrician when these symptoms develop in their child. Hence