Hypoxic respiratory distress potentially secondary to phosphorus trifluoride gas exposure

We herein report a rare, probable exposure of a patient to phosphorus trifluoride gas. The objective of this case report is to highlight the potential exposure to phosphorus trifluoride gas and discuss the best management of it. A 48-year-old worker at a specialty gases laboratory was transported to the community Emergency Department (ED) in respiratory distress, presenting with peripheral cyanosis, an unobtainable oxygen saturation, chocolate-colored blood, and a Glasgow coma scale of 15. A non-rebreather was placed, poison control was contacted, and the patient was administered empiric methylene blue intravenously due to worsening cyanosis and respiratory distress. Upon arrival at the academic facility, the patient was no longer cyanotic and reported improvement of his symptoms. The patient's employer informed staff that a canister of phosphorus trifluoride gas in his workstation was found to be empty but should have been full. It was also discovered that a coworker left work early the same day with similar but milder symptoms. Hyperbaric oxygen therapy was considered; however, the patient was improving on oxygen via non-rebreather, and he had no other indications. Because the patient continued to require supplemental oxygen to maintain their oxygen saturation above 92%, he was admitted to the ICU and treated with prednisone daily for chemical pneumonitis. After 4 days, he successfully transitioned to room air without hypoxia. While exposures such as this do not occur frequently, it is important to maintain a broad differential and treatment plan as we continue to investigate the etiology and best treatment option.