A patient with heart failure has gained 3 kg in four days and now reports orthopnea. The weight trend and respiratory symptom point toward recurrent congestion, so the first nursing priority is respiratory and perfusion assessment while preparing the ordered decongestion plan. If the same patient has a blood pressure of 82/50 mm Hg, cool extremities, confusion, and scant urine, the problem is no longer uncomplicated fluid excess; hypoperfusion or shock must be escalated before aggressive diuresis. A second patient begins hydrochlorothiazide and returns with unsteadiness and confusion two weeks later. The timing and neurologic findings should trigger an immediate sodium check and safety precautions. Calling the symptom “expected increased urination” misses the treatment-related hyponatremia that can progress to seizure. A third patient taking furosemide and digoxin reports nausea and sees yellow-green halos. Do not focus only on the diuretic. Check potassium, magnesium, renal function, rhythm, and digoxin toxicity risk; the diuretic may have created the electrolyte conditions that made digoxin dangerous. The exam distinction is consistent: expected diuresis is not the same as effective decongestion, a modest creatinine change...