Diuretics and Electrolyte Shifts

Diuretics are not interchangeable “water pills.” Each class acts at a different nephron segment, so the site of action predicts which electrolytes will be lost or retained, how volume status will change, and which adverse effect becomes dangerous. The nurse is evaluating two outcomes at the same time: - Is excess fluid being removed? - Is removal causing hypoperfusion, kidney injury, dysrhythmia, or neurologic injury? A larger urine volume does not automatically mean successful treatment. A patient with pulmonary congestion may need brisk diuresis, while a patient who is dizzy, tachycardic and rising in creatinine may need the next dose held for review. The clinical story determines whether a change is therapeutic or harmful.