Final answer:
The ED nurse should prioritize monitoring potassium levels when a patient with pulmonary edema is being treated with IV furosemide (Lasix), as the medication can cause hypokalemia, leading to serious health complications.
Step-by-step explanation:
The emergency department (ED) nurse is caring for a patient who is experiencing pulmonary edema and is being treated with IV furosemide (Lasix). The priority for the nurse to monitor in this situation is d. Potassium levels.
Furosemide is a potent diuretic that works by inhibiting the reabsorption of sodium and chloride in the loop of Henle in the kidneys. This leads to increased urine output, which can help to alleviate pulmonary edema. However, because furosemide increases the excretion of sodium and water, it can also cause the excretion of potassium, which can lead to hypokalemia (low potassium levels). Monitoring potassium levels is critical because potassium is vital for normal cell function, including heart rhythm regulation.
Therefore, the nurse must closely observe the patient's potassium levels to prevent potential complications, such as cardiac arrhythmias, associated with hypokalemia.