BP issues

I’m on my neuro placement at the moment and treating a pt that had a stroke about 5 weeks ago, his PMHx also includes parkinsons disease. This pt was doing really well for the first few weeks post stroke and managing to walk back to his room after the physio session with the assistance of the PT students there at that time. Over the past 2-3 weeks this pt’s BP has been up and down. At 8.30 in the morning it can be up to 190/100 and then an hour later 80/40 just when we want to start our PT session with him. On this placement we are expected to try see our pts twice a day, but more often than not recently this pt who is normally hypertensive has a BP around 80/40. I’m working with another PT student with this pt and a few times now we have taken this pt to the gym when his BP has looked good, done some foot mobilizations, checked his BP again just before standing or transferring to the plinth and it’s plummeted again and we have to get him straight to bed again. It’s quite a frustrating thing for the pt, his family and us pt students because he has now gone backwards with his rehab because he is not getting the gym sessions he needs.
Unfortunately there is nothing we can do about his BP, the Dr’s are trying to work it out. To deal with this issue we have had to do a lot more sessions in his room when his BP is not great but this often only includes some UL and LL exercises to maintain ROM and strength and foot mobilizations as his feet have a lot of tone and this is not an ideal situation. We have managed to get him to the gym almost once a day in the past 1.5 weeks but as it is not as frequent as we would like, he is not making the same gains as he was when first admitted. We do all we can for the pt and have to modify our treatments to suit their situation. When his BP is stable we do as much as we can in the gym to prepare him to try get him up into standing and with his added PMHx of parkinsons it adds more challenges, so as yet we have struggled to get him to stand with his COG over his BOS but we are hoping to have some good BP days so the gym sessions can start to progress from one to another