A patient with heart failure has received sublingual nitroglycerin and intravenous furosemide for pulmonary edema. What is the priority nursing intervention?

Choice A reason: Monitoring serum glucose is not a priority in this context unless the patient is diabetic or receiving medications that affect glucose levels. Neither nitroglycerin nor furosemide directly necessitate glucose monitoring as a primary concern. Choice B reason: Monitoring blood pressure is critical because both nitroglycerin and furosemide can cause hypotension. Nitroglycerin is a vasodilator that lowers preload and afterload, while furosemide is a diuretic that reduces fluid volume. Together, they can significantly drop blood pressure, risking hypoperfusion and shock. Choice C reason: Inserting an indwelling catheter may be necessary for strict intake and output monitoring, especially in acute heart failure, but it is not the immediate priority compared to hemodynamic stability. Choice D reason: Placing nitroglycerin under the tongue is the correct route of administration, but the medication has already been given. The priority now is to monitor its effects, particularly on blood pressure.