I can totally sympathize with your situation. Jack was diagnosed with Megacolon back in 2007.

You didn't specify which meds your kitty is on. My Jack is on Cisapride to keep the stools mobile in addition to the diet and other meds to keep the stool soft. Is your kitty on Cisapride already?

I had a consultation appointment with a internal medicine specialist and they said they wouldn't consider surgery for Jack unless the meds stop working or he requires more than 2-3 enemas a month. Fortunately Jack hasn't needed an enema since we started the Cisapride & Lactulose along with the high fiber diet.

What the specialist had told me regarding the surgery, worst case scenario was diarhea for up to 6 months, although their experience was more like 6-8 weeks in reality. They told me that they had only a few that had needed to undergo a second surgery for the problem, but it was always a slim possibility. In their opinion the surgery was a last resort and their experience was that most of the cats went on to have long, healthy lives after the recovery.

My thoughts are with you in this situation.