Final answer:
When spironolactone and lisinopril are used together, the primary assessment by the nurse is the risk of hyperkalemia, an elevated potassium level in the blood.
Step-by-step explanation:
The hospitalized patient is receiving spironolactone (Aldactone), a potassium-sparing diuretic, and a consulting physician has ordered lisinopril (Prinivil), an ACE inhibitor. When used together, these medications can lead to hyperkalemia, which is an elevated level of potassium in the blood. This condition is potentially life-threatening and affects the normal rhythm of the heart, which is why it will be the primary assessment by the nurse.