Geff,
Look at me my friend. Just got the same procedure you're having mere days ago (july 23rd) and it went great. There are so many success stories here which will provide you assurance that you would be on the other side before you know it. You will be giving similar advice to others like a pro very soon
Having some level of anxiety beforehand is normal too. There've been some suggestions provided regarding mindfulness on this thread, so please try them out. I tried breathing exercises with eyes closed and it worked for me. Mind likes wandering, allow -ve thoughts to pass. They are fake and fabricated, and not true. True is the hundreds of testimonies here. Fill your imagination with a number of positive things awaiting you on the other side. There's a lot of excitement ahead, I promise
On the day of surgery, I was fairly conversational with the staff as they prepped me, which worked for me.... I even cracked jokes with my family in the waiting area. Do whatever keeps you in high spirits.
Those professionals who will be working on you know what they are doing and have done this everyday. Trust them my friend. Give them the "control", like you give to the pilot who flies your airplane when you travel. That giant of a piece of iron with 300+ passengers can fly 36,000 feet in the skies, even under turbulence, for hours by a human (pilot) with the assistance of technology. Your bentall procedure is the same thing too. It's all figured out by technology and surgeon and his/her staff. You are a mere passenger. Trust them.
And trust someone above and around.
YOU WILL BE FINE.
Every country has its own procedure e.g. checking in earlier (rather than getting tests done as outpatient). It's not uncommon. Pre-op tests are the same for everyone and necessary. I say being in hospital earlier would help you assimilate to the climate and provide further assurance that you are in good hands.
All the very best. You will do great and we will see you on the other side soon