There can be fall-out from a decision to have a dementia patient travel.
During the trip you should expect more exaggerated emotional responses. If the person is likely to cry, anticipate tears. If the person tends towards aggression, anticipate a shorter fuse. If the person is one who wanders, consider temporary door alarms or even a black rug or towel in front of the door. I have not yet tested the rug, but the theory is that it is perceived to be a hole and not crossed.
After the trip is over, it will take the patient longer to get back into their own swing of things. You may find the person sleeps longer or is more confused. You may find that they are unable to recall specific events experienced on the trip.
Just hang in there. Things will sort out and within a few days, the individual should feel more settled by having been returned to their familiar environment and routine.
With Lyn, we saw increased agitation on the day she and Mom returned home. She showed more confusion at the airport and even start to head to "her"gate in the wrong direction. Mom was quickly able to wrangle her. The following couple of days also saw an increase of sleeping which may have additionally been triggered by her period starting extra early as well. At one point, Lyn asked if they could come back to my place next year. A few hours early, she cried while saying she didn't want to come again because it was too hard.
It was a challenge and we significantly modified how the visit was conducted. However, we are very glad that we did it. Lyn got to see our brother and his child. Mom got to spend Thanksgiving and her birthday with her children and grandchildren. All of this and the quiet moments we had together made it absolutely worthwhile.