Pyschogenic Polydipsia

A Long Term Care facility I am currently working at, has recently had long term psychiatric residents transferred there from the institution they had resided in, one for 60 years. One problem is how these residents can be assessed to fit into the RCS funding tool that was developed primarily for frail aged dementia residents. There are many areas that concern me, however, if I can raise one issue at this time and receive some responses I will be ever grateful. A Down's Syndrome with pyschogenic polydipsia - Would any one have a management plan for polydipsia, I feel that this should be claimable in hydration management, challenging behaviour and RN management planning. I feel that the Government review officers may disagree, so would like some support if any one agrees.