A nurse is caring for a client with chronic obstructive pulmonary disease (COPD) experiencing an acute exacerbation. Which of the following oxygen delivery methods should the nurse use?

Choice A reason: A nasal cannula at 2 L/min delivers low-flow oxygen (24-28% FiO2), insufficient for a COPD exacerbation, where hypoxemia is severe due to airway obstruction and ventilation-perfusion mismatch. It cannot provide precise, high FiO2 needed to correct hypoxia while avoiding excessive oxygen, which may suppress respiratory drive in COPD patients. Choice B reason: A simple face mask at 10 L/min delivers 40-60% FiO2 but lacks precision in oxygen concentration. In COPD, excessive oxygen can reduce respiratory drive, causing CO2 retention due to the hypoxic drive mechanism. This makes it less suitable than a Venturi mask, which provides controlled oxygen delivery. Choice C reason: A non-rebreather mask at 15 L/min delivers near 100% FiO2, which is excessive for COPD exacerbation. High oxygen levels can suppress the hypoxic drive in COPD patients, leading to hypercapnia and respiratory failure. Controlled oxygen delivery is needed to balance oxygenation and CO2 retention risks. Choice D reason: A Venturi mask at 40% FiO2 delivers precise oxygen concentrations, ideal for COPD exacerbations. It balances hypoxemia correction with the risk of CO2 retention by providing controlled FiO2. This prevents suppression of the hypoxic respiratory drive while ensuring adequate oxygenation, making it the preferred method for acute COPD management.