There's one of two scenarios:
1. He has a loop ileostomy and has his jpouch made but non-functioning. If this is the case the second surgery is quite simple, close the ileostomy and the pouch starts working.
2. He has a loop ileo and had most but not all of his rectum removed, but the pouch is not made yet. If this is the case the second surgery is a bit more complicated.
Best to find out from his surgeon where he exactly stands.
Sue