What is the cause of prerenal oliguria?

Prerenal oliguria is mainly caused by blood loss or reduced blood volume or dehydration. When the body's blood volume is reduced, or blood loss, blood will be redistributed to ensure blood supply to the heart, brain and kidneys. In order to reduce the loss of blood volume, urine excretion will be reduced, which will show prerenal oliguria. After showing prerenal oliguria, active treatment is needed. If long-term oliguria, it may cause renal failure. Therefore, after showing prerenal oliguria, diuretics need to be applied to promote urination and prevent renal failure.