Various causes Rapidly and severely decline of gFr Kidneys fail to excretion and regulation in hours to days Oliguria or anuria Retention of nitrogenous wastes(azotemia) water/electrolyte acid-base disturbance Oliguria is usually emphasized in the past, but in some cases does not change. It is called non-oliguriaaRp urine volume patients have high level bun(azotemia) while 1616 Oliguria or anuria Retention of nitrogenous wastes (azotemia) water/electrolyte acid-base disturbance Rapidly and severely decline of GFR Kidneys fail to excretion and regulation in hours to days Various causes Oliguria is usually emphasized in the past, but in some cases, patients have high level BUN (azotemia) while urine volume does not change. It is called non-oliguria ARF