I remember reading where someone with the Indiana Pouch mentioned that they use some tape to tape the catheter hose to their tummy.
I have a neobladder so I don't know first hand. I'm sure others with pouch will let you know their secrets for this because it sure sounds like a common occurence.
I do wear a condom catheter at night with my neo and I have had a few times where the tip of the condom part where it connects to the catheter bag hose gets twisted. That kinda sucks as it causes the condom part to start filling with urine until it eventually starts leaking all over the place before it wakes me up. Doesn't happen often enough to mess with tape as I don't get along well with tape adhesives on my skin generally. I know it's a whole different problem, but it is similar. If it happened to me a lot (more than once every 4 months or so) then I'd research tape adhesives that would work for me, shave my upper thigh and tape the hose to my leg to avoid the problem.
I do use a washable mattress pad under the sheets though just in case and you may want to do that also to handle any accidents.
By the way, welcome to the site. Glad you made it here and you posted a great question. It is one of those that will certainly help others (when we get some answers from other IP folks).
Mike
P.S. Feel free to share your experiences adjusting to the pouch. The more of that type of information that gets shared, the better. It helps others learn.