Gwyn had two cases of acute pancreatitis.
Medically, we put her on painkillers (buprenex, .25cc every 12 hours, though I later checked with the vet and changed it to half the dose twice as frequently (.125cc every 6 hours) and we did sub-Q fluids roughly every 36 hours.
I also can't recall for certain, but we may have put her on an increased dose of prednisone (Gwyn's on pred anyway, so an increase in dose doesn't really register with me), and I'm fairly certain we put her on Pepcid as well. And we may also have used cyproheptadine as an appetite stimulant.
Other things I did was to bring food and water to her every couple hours around the clock, so that she didn't have to get up and move around to eat -- I wasn't sure if the movement to get to the bowl was causing pain and I didn't want to risk it. If I noticed that she looked like she wanted to use the litterbox, I carried her there and back, and tried to provide support to her if she seemed to need it when she was using it.
I also moved both the litterbox and food and water bowls fairly close to her, so that she wouldn't have far to go if she went on her own. When I fed / watered her when she was lying down, I braced her shoulder up and pushed the bowls down into the matt so it was lower than her shoulders, then angled the bowl toward her so it was easy for her to poke her head in for a bite. Also, with the bowl angled, she could push the food against the bottom of the bowl to help get it in her mouth.
I built a nice little cat-nest on the floor near everything, but she wasn't interested; she wanted to sleep on the couch. So I used the encyclopedia set to build a set of long, very low steps up to the couch, so she could get up and down herself without having to jump. I spent most of my time in the room with her and slept on the couch with her so that I'd notice if she needed anything, and I'd lift her on / off the couch as needed, but I wasn't there all the time and I wanted her to have an option that wouldn't make her use her stomach muscles as much.
Both of Gwyn's attacks were acute pancreatitis (not chronic; the attacks were 14 years apart), and took about a week to resolve.