I am an RN, used to be a CNA- have worked in geriatrics for 11 years total. I have worked for the last four years on an acute care geriatric psychiatric unit, affliated with a major hospital in NE. In my opinion, whether the patient can be properly cared for on an acute medical unit(inpatient psych units for all ages are also acute care-just different kind)depends upon the mental illness. Pts who suffer from dementia and sometimes schizophrenia, or who are actively psychotic, detoxing, or hallucinating for some other reason- possibly drug toxicity such as Lithium; in my opinion- do very poorly and in fact may have more complications if placed on a medical unit.
I say this from experience having received many patients from the med-surg units. There seems to be a trend with patients with these illnesses. They are "thrown off kilter" just by being ill(may not be able to cope with the changes in their routines or environs), add to that, being on a (probably) noisy, chaotic unit with many different people in and out, painful procedures at times and medications and machinery all around and it is a recipe for disaster. Not to mention the expectation that the patient stay in bed rather than wander, do what they are told and do it quickly, not disrobe or innapropriately toilet themseves, or attempt to "defend themselves" from their hallucinations/delusions by hitting other patients etc..It has also been my experience that many nurses have some fear of demented, agitated elderly AND have NO way of managing them on that type of unit so that everyone is safe; no way to decrease stimuli, or allow wandering. I could go on and on, if you would like to discuss this further, feel free to email me @ email@example.com. Hope this helps. I also have seen more geriatric psych literature lately when searching on the internet.