How does a kidney failure patient who undergoes dialysis three times a week fast?

Hemodialysis invalidates the fast because it involves drawing blood from the body, purifying it, and adding nutritional and chemical substances to it before returning it. Wudu is not invalidated by the exit of blood during dialysis, because what invalidates wudu is only what exits from the two private parts. It is permissible for those undergoing hemodialysis to combine prayers (Dhuhr and Asr, Maghrib and Isha) coordinating with the doctor to perform the prayer at its time. Whoever suffers from kidney failure may break their fast on dialysis days and must make up for them if able; otherwise, they must feed one poor person for each day.