Carbon monoxide (CO) is a leading cause of morbidity and mortality. Treatment focuses on the rapid elimination of CO and management of hypoxia. Oxygen is the cornerstone of therapy, and usually applied via a reservoir face mask. Hyperbaric oxygen therapy eliminates CO faster, but requires extensive equipment and expertise. Non-invasive continuous positive airway pressure (CPAP) ventilation using a tight mask provides a higher inspired fraction of oxygen (FiO₂) compared to a reservoir face mask, and increases gas exchange. As this modality is widely available, it might represent a supplemental approach to current treatment of CO poisoning.

We present two simultaneous cases of a married couple of 31- and 34-year-old patients, who concurrently suffered CO intoxication due to a faulty gas heater in their apartment. Both reported similar symptoms of headache and weakness, and carboxyhemoglobin (COHb)-levels at admission were 21% in both patients. One patient was treated by non-invasive CPAP-ventilation support with a FiO₂ of 100%, whereas the other was treated by conventional oxygen inhalation. In the patient treated by CPAP, COHb-levels fell quickly to 6% within one hour, and reached 3% after 90 min, whereas it took six hours to reach the same levels in the patient with conventional treatment.

This vividly illustrates the potential of CPAP therapy as an alternative to conventional oxygen inhalation in the treatment of CO poisoning.