A patient is exhibiting severe hypoxemia with a DNI directive. What should the therapist do to maximize arterial oxygenation?

To maximize arterial oxygenation in a patient exhibiting severe hypoxemia, particularly under a Do Not Intubate (DNI) directive, utilizing a non-rebreather mask with flow set to flush is an appropriate approach. Non-rebreather masks are designed to deliver high concentrations of oxygen to patients with significant respiratory distress or low oxygen saturation. By using a non-rebreather mask, the therapist minimizes the mixing of exhaled air with the oxygen being supplied, which helps ensure that the patient receives the highest possible fraction of inspired oxygen (FiO2).

This method effectively maximizes the amount of oxygen in the patient's bloodstream, which is critical when severe hypoxemia is present. The flush flow setting on the oxygen supply ensures that the mask remains adequately filled with oxygen throughout the patient’s breathing, further enhancing the efficiency of oxygen delivery.

In contrast, other options may not provide the same level of oxygenation or could compromise the patient's care under the DNI directive. For example, using non-invasive positive pressure ventilation can be beneficial in certain scenarios, but it might not deliver the high FiO2 needed during severe hypoxemic events. Similarly, an air-entrainment mask would typically provide lower concentrations of oxygen relative to a non-rebreather