I was drinking coffee and tea while the cath was still in (doc had no issues with that, as you need fluids, and any hot liquid helps motivate the bowels), but the physical therapy nurse had me stop it immediately when the cath came out. She told me (and I heard this from doctors as well) that the caffeine was not an issue, so caf/decaf was irrelevant. The issue is the acids in the coffee which irritate the bladder.
I went completely off coffee, and with the start of RT with it's "predictable bowel" requirements, I stayed off it. Over time I have started my espresso again.