I went through this with Gabriel who went into renal failure. I was advised to attempt to give cornstarch baths ( i'll attach a link for this) so as not to wet him everyday but after several days of cornstarch baths he got pretty funky and I ended up giving butt baths. So i would do the cornstrch some of the time and the butt bathes when he really got funky. I used the plain cornstarch that you buy in a grocery store to thicken gravy etc...not anything with talc ior perfume in it.
make sure that you use a small animal shampoo ( Maybe your vet could prescribe a shampoo) and not human soap as rabbit skin is far more delicate than human even human infant.
This is what i did and then I'll attach links ...
I would bathe his butt each morning , very gently and then use a hair dryer on low to dry him... he put up with this fairly well as he was weak. then I would apply neosporin to the affected area (in his case it ws the genitals which were really really red and inflamed. After iIapplied the neosporin..I would apply diaper rash ointment . I bought the generic kind from walgreens which has zinc oxide.
He was not grooming himself so I didn't worry about him ingesting it.
I did this every morning for weeks and eventually I cleared up the urine scald , however his kidney failure didn't clear up and he is in heaven now.
he did not have EC but had been dehydrated and starved prior to me rescuing him.
This is what I did but I know that there are absorbent pads that you could keep your bun on and also probably other methods to help him that i didn't use
I tried to do the most cost effective treatment so just washed a ton of towels each day.
I know from experience how hard this is to deal with . my heart goes out to you ....
http://www.bio.miami.edu/hare/buttbath.html
http://www.bio.miami.edu/hare/urinary.html
http://www.rabbitsonline.net/view_topic.php?id=12158&forum_id=10
http://www.rabbitsonline.net/view_topic.php?id=14471&forum_id=10
I also hope that randy post ..
he has a lot of expertise with EC
Let us know how things go..:hug: