What should a nurse monitor most closely in a patient receiving IV potassium?

Monitoring heart rhythm is crucial for a patient receiving IV potassium because potassium plays a vital role in cardiac electrical activity. An imbalance in potassium levels—whether too high (hyperkalemia) or too low (hypokalemia)—can lead to serious cardiac dysrhythmias, which can be life-threatening. Changes in heart rhythm, such as peaked T waves or the risk of ventricular fibrillation, can occur as potassium levels fluctuate, making this assessment critical for patient safety.

While urine output is important for assessing kidney function and the excretion of potassium, the immediate threat to life posed by potential cardiac complications makes heart rhythm monitoring the primary focus. Blood pressure and serum creatinine levels are also useful indicators of a patient's overall health and kidney function but do not directly inform the immediate risks associated with potassium administration. Therefore, close observation of the heart rhythm ensures timely intervention in the event of complications related to potassium infusion.