Abstract
Background Although commonly used inside hospitals, no previous case report has been published on high-flow nasal oxygen (HFNO) therapy in an adult in the prehospital setting. Case Report A 46-year-old nonsmoking man presented with a cough and fever. He deteriorated suddenly 5 days later. When the basic life support team arrived, his peripheral oxygen saturation (SpO(2)) in ambient air was 56% and respiratory rate was 46 breaths/min. The man was weak with thoracoabdominal asynchrony. An emergency medical team with a physician was dispatched. As France was still under lockdown for the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) pandemic, COVID-19 (coronavirus disease 2019) was suspected. In spite of 15 L/min of oxygen delivered with a nonrebreathing mask, the patient's SpO(2) tended to drop below 90% at the slightest effort and during transport from home to the ambulance. It was therefore decided to start HFNO therapy. The patient was transferred to an intensive care unit, where HFNO was continued. Why Should an Emergency Physician Be Aware of This? As the trend in emergency medical services may move toward prehospital HFNO, this case report is an opportunity to question the feasibility of HFNO therapy in the prehospital setting.