Diagnosis
Common presentation: During the winter/cold months, a patient comes in with an acute SOB, tachypnea, tachycardia, nausea, and a headache. The patient looks very ill. Pulse oximetry shows an oxygen saturation of 100% on room air. ABG shows a PaO2 of 96 mm Hg.
Common manifestations: Symptoms include a headache, nausea, vomiting, and weakness, a flushed skin complexion. Symptoms commonly attributed to viral flu-like illnesses because they are so similar.
Diagnostic testing
Pulse oximeter often shows oxygen sat of 100%. ABG shows normal PaO2. This helps to distinguish CO poisoning from other serious causes of respiratory problems like pneumonia, ARDS, or methemoglobinemia which would produce abnormalities on pulse oximetry or arterial blood gas measurements.
To detect CO poisoning directly, you need to order either a CO level or a co-oximetry test.
Background
Exposure to CO most commonly results from fuel combustion in heaters, stoves, or automobiles. As such, you see it more during cold seasons when people are in closed quarters.
Pathophysiology of CO poisoning.