Put me on anti-spicotic drugs, n i have same heart condition. Blood pressure dropped to 70 over 60. Got really ill, told me to keep up with medicine! By now i was suffering from distonia, glacoma/cateracts, n an enlarged prostate! Looked at there report, & they said i was fine to make my own decisions. Then it said, DO NOT RESESITATE! I got the h--l out of that hospital, but now i think i have dimentia, besides all the swelling in my ankles, & numness, all on my right side. I could sleep for hours, n days, but after 8 hours of sleep have to force myself to get up, so i can move around, so my body doesnt lock up with pain. BAD PAIN!
As a former nurse, I found that when treating the elderly, they would easily become confused after a period of time in the hospital, especially if they were in the ICU where there is plenty of noise and lack of sleep. This is hard on a young person, the elderly seem to be more sensitive to this...at least that is what I have observed. Your father has been in the hospital for quite some time, he probably isn't sleeping well (hospitals aren't conducive to good sleep patterns as the patients are woken up at all hours) and his health is brittle as well. All of this could easily be contributing to his dementia. The term that is used amongst ICU patients exhibiting symptoms that you describe is ICU psychosis. There are medications that can help with this, you should talk to the doctor and relay your concerns to him or her.
Jenn