Less than 24 hours urine volume is oliguria

Oliguria is defined as a 24-hour urine output of less than 400ml. Acute kidney damage may occur due to sudden decrease in urine output, which should be given full attention. Normal 24-hour urine output is 1000-2000ml. Anuria and oliguria are caused by decreased renal output. Anuria is defined as a 24-hour urine output of less than 100ml, persistent anuria, seen in organic kidney damage, manifested as azotemia and uremia. Clinically, urine volume reduction may be prerenal, renal or postrenal, and it is necessary to determine whether there is oliguria or anuria caused by ureteral or urethral obstruction.