In the event of an unexpected decrease in oxygen saturation, what should be the first course of action?

In the event of an unexpected decrease in oxygen saturation, the most critical first action is to check the patient's airway. Ensuring a patent airway is fundamental in emergency situations, as any compromise in airflow can directly affect oxygenation. If the airway is obstructed or not functioning properly, any adjustments to oxygen delivery or ventilator settings would be futile.

By checking the airway first, you can quickly assess if there is any obstruction (such as from secretions, positioning, or foreign bodies) that needs to be addressed in order to restore adequate ventilation and oxygenation. This proactive step not only helps in stabilizing the patient but also provides valuable information on the need for further interventions.

Adjusting the FIO2, administering bronchodilators, or changing the ventilator mode may indeed be necessary steps following the assessment of the airway, but they assume that the airway is clear and functioning properly. Starting with the airway ensures that the most critical element of respiration is addressed immediately.