If you have an extra bathroom that can be designated for his use it would be handy. We have an 2nd bath that my wife set up for me with a small folding table in it. It was real helpful for me for having all my stuff in one place where I did not need to bend over for it. On the table were:
three different types of depends, the diaper type, pull up type and pads
washcloths
wipes (they say to use the adult wipes and not baby wipes) for urinary leakage
baby diaper rash lotion (I had really bad rashes from the leakage)
something to read (helps with the BM's) word search puzzle magizine was great!
surgical dressing tape for holding cathedor tubes in place
clipboard and paper pencil to make notes of things for the doctor
also handy were
an old pair of pajama bottoms that you can cut one leg off at the knee, makes it easier to route the cath tube.
once the cath is out you will of course need a good airtight wastbasket with liners for used pads.
Hope all goes well, the post surgery time really passes quickly.