Can a doctor be a patient's guardian?

I'm reading that the court appointed the head of the psychosomatic department as a guardian for his patient, and now a lot of questions have arisen. If a person is undergoing treatment in an institution, is it normal for the head of that department to become their official guardian? Won't there be a conflict of interest here, and is it legal at all? It seems to me that guardians should usually be relatives or close people, not medical workers of the institution where the ward is being treated. How should this work correctly under Ukrainian law?