The nurse is caring for a patient who is receiving IV furosemide (Lasix) and morphine for the treatment of acute decompensated heart failure (ADHF) with severe orthopnea. Which clinical finding is the best indicator that the treatment has been effective?

Correct Answer: D

Rationale: Because the patient's major clinical manifestation of ADHF is orthopnea (caused by the presence of fluid in the alveoli), the best indicator that the medications are effective is a decrease in dyspnea with the head of the bed at 30 degrees. The other assessment data may also indicate that diuresis or improvement in cardiac output has occurred but are not as specific to evaluating this patient's response.

Correct Answer: B

Rationale: Anterior cardiac veins drain directly into the right atrium, bypassing the coronary sinus.

Correct Answer: D

Rationale: Sympathetic stimulation increases the rate of depolarization in the SA node, raising heart rate.

Correct Answer: D

Rationale: Juxtaglomerular cells in the kidney secrete renin in response to low blood pressure or sodium levels.

Correct Answer: D

Rationale: Increased potassium permeability hyperpolarizes the AV node, slowing conduction and heart rate.