Q: Despite little evidence, it is a common practice to give high dose of loop diuretics to mask oliguria in Acute Tubular Necrosis (ATN). Which one side effect is highly under appreciated in ICUs of high dose infusion of loop diuretics?

Answer:  Ototoxicity

High single dose IV furosemide or bumetanide (bumex) is commonly used to reverse oliguria in ATN, although little evidence proves that it changes the course of ATN. Loop diuretics affect the potassium gradient of the stria vascularis, as well as the electrical potential of the endocochlear structure. These medications produce tinnitus and hearing loss. Their toxicity is dose-related.

Furosemide-related ototoxicity is usually reversible but may stay permanent, particularly in patients who goes in full blown renal failure. If absolutely desired, single dose can be given on a trial basis slowly. If no response occurs, it is recommended to avoid further high doses.