How do you know if your liver or kidney is going out?

Need evaluation: If you mean by "going out" not functioning well. There are several blood tests that will give an answer. Specific kidney tests include the blood creatinine, bun, and electrolytes. Specific liver function tests include liver enzymes called transaminases and bilirubin. There are of course symptoms related to dysfunction of each of these organs, including retention of fluid and swelling.