Cough Reflex Test (CRT) Practice Exam 2025 - Free CRT Practice Questions and Study Guide

In patients with severe COPD who exhibit lethargy and shallow respirations, it's crucial to select an oxygen delivery method that provides adequate oxygen while minimizing the risk of hypercapnia (excessive carbon dioxide in the bloodstream).

Using a 28% air-entrainment mask, also known as a Venturi mask, offers a controlled and precise oxygen concentration. This is particularly beneficial for COPD patients because it allows for the delivery of a consistent and lower oxygen concentration compared to non-rebreather or simple face masks, which can supply higher levels of oxygen. In COPD, excessive oxygen can suppress the drive to breathe, leading to worsened respiratory status.

The air-entrainment mask achieves this regulation by mixing a specific percentage of oxygen with room air, ensuring the patient receives adequate oxygenation without the risk of over-oxygenation. This method not only supports adequate oxygen saturation but also helps support the patient's respiratory function without overwhelming their respiratory drive, which is essential for patients with compromised lung function.

Adjusting to a non-rebreather mask or increasing the flow rate of the nasal cannula could potentially provide higher oxygen concentrations, which may not be safe given the risk profile for patients with severe COPD. A simple face mask may also deliver too high