A 68-year-old male reports worsening breathing difficulty when climbing stairs. What is the best intervention?

Administering oxygen by non-rebreather mask is a suitable intervention for the patient experiencing worsening breathing difficulty, especially given his age and the nature of his symptoms. Non-rebreather masks are designed to deliver high concentrations of oxygen to patients with significant respiratory issues or those who present with hypoxia.

In this scenario, the patient is showing signs of respiratory distress, which can indicate conditions such as chronic obstructive pulmonary disease (COPD) or heart failure. Providing high-flow oxygen can help improve arterial oxygen saturation quickly, addressing immediate hypoxia and alleviating the strain on the patient's respiratory function.

Although other options may have their merits in different contexts, a non-rebreather mask is specifically effective in acute situations requiring high levels of oxygen to maintain adequate oxygenation, particularly in patients who may be unable to maintain their oxygen saturation adequately on room air.