What Does The Following Test Result Mean?

How long can there be swelling of the brain tissue in the right hemisphere of the brain before another stroke or possible brain death? 62 yr old male- he had a carotid endarterectomy on Friday, 03/18/2016. He was discharged on 3/19 less than 24 hrs post-op with complaints of ipsilateral headache (w/ blurred vision). He was not given any prescriptions for steroids, told to take 3 Advil for pain. He maintained an ipsilateral headache over the next several days, on 3/22 approx 9am, he had a stroke at home and was rushed to the hospital and was on the vent until 3/25 when the vent was removed. He was/is alert...he regained mobility of his left limbs but his mental status was altered. His memory, however was great and he knew all his visitors and could carry on short conversations. He had some hallucinations or confusion at that time. NOW, today- 3/27, Dad s MRIs show no decrease in swelling even though his mobility on his left side has improved. He has signs of dementia, which to me seem to be worse than before because now he is forgetting our names. He stares like he is in a trance...attention span is very short, and he gets fixated on things and repeats himself all the time. The doctors claim they cannot see if he has had a stroke due to the swelling...and until the swelling goes down there is really nothing we can do. It has been almost 6 days and there has been no decrease in the swelling of the brain tissue. Steroids are not working and as far as I know, that is the only medication they have given him for it. They removed him from the vent, so could it be carbon monoxide build-up on the brain with the poor circulation up there from the swelling? Any ideas? I am worried that the sit and wait is not smart and that something needs to be done to decrease the swelling asap. I am also worried about his stroke could have caused some bleeding or a ruptured vessel behind the swelling that is being untreated. I am just trying to see if anyone can help us. I want him transferred to another hospital that is more familiar with strokes and are better equipped to deal with him...but the hospital has my mother convinced that he shouldn t leave because he is their post-op patient in the first place. Help.