Possible CO Poisoning

60 years old male patient with ICD. Known Hypertension patient. A patient who complained of severe headache and syncope for a few minutes after instantaneous exposure to stove smoke while cleaning the chimney. He was brought to our center by 112 Emergency Ambulance (911 equivalent in Turkey). According to the statement of the health personnel who delivered, his vitals were measured as GCS: 15, Arterial Blood Pressure(ABS): 160/100 mmHg, SpO2: 95 in his first examination. The patient, who was brought with 5 lt/min O2 treatment, complained of nausea and vomiting. Neurological examination of the patient, whose vitals were GCS: 15, ABS: 140/90 mmHg, SpO2: 99 (with O2), was normal. Hemogram, cardiac and extensive biochemical blood tests were taken from the patient who had nausea, vomiting and headache. 10 lt/min O2 and symptomatic treatment was given to the patient whose ECG did not show any emergency pathology. The Forensic Report of the patient, who was evaluated as CO Poisoning, was prepared and he was referred to a higher level for Blood Gas measurement without waiting for the blood results.

Do you consider CO poisoning as a differential diagnosis in your patients with similar complaints?

What other diagnoses would you consider in this patient?

From my SERMO page: https://app.sermo.com/post/856747