When assessing a patient's airway, what is the most critical step?

When assessing a patient's airway, ensuring that the airway is clear of obstructions is the most critical step. A clear airway is essential for adequate ventilation and oxygenation. If the airway is obstructed, despite the presence of breathing sounds or otherwise normal lung function, the patient cannot effectively exchange air, which can lead to hypoxia and respiratory failure.

Establishing a clear airway allows for any necessary interventions to take place, such as providing supplemental oxygen or performing advanced airway management if needed. Thus, prioritizing airway patency is crucial, as it directly impacts the patient's ability to breathe and receive oxygen. Other aspects of assessment, such as checking breathing sounds or evaluating lung expansion, are important but secondary to ensuring the airway is not obstructed.