Because I do not know as much about ARF - Acute Renal Failure - perhaps we should have a seperate thread for that.
I want to put in one place, the resources I've used in dealing with CRF kitties for about 5 years now, and for us all to share additional links, and our experiences.
I know the first time I heard this diagnosis, with my beloved Patrick, I was heartsick. I knew little about what could be done and was SO not ready to have this special cat in my life, leave. He was 15. He lived to just under a month from his 19th birthday, with his CRF still in good control, but with other sudden health issues that we could not control.
I did some websearching and stumbled on two sites, one of which is my favorite and the one I recommend. Tanya's Site - www.felinecrf.org though written by someone who at the time was living in Europe, is filled with accurate information, kept up to date, and as a bonus lists supply sources in Europe (Britain only I think) as well as lists lab values both in as measured in the US as well as overseas.
It is an extensive site, it goes over diagnosis, what symptoms are seen, what they mean, what the lab results mean, treatments/medications, including studies done or ongoing, holistic approaches, related health issues and so much more.
I learned that dehydration is so key to address, increased stomach acid and nausea both affect crf kitties and their appetite (as does a too high phosphorous level..to be abbreviated as phos for the rest of this message), that crf kitties are prone to low potassium due to the high urine output that they have, so many require potassium supplementation, constipation is another frequent issue.
I lucked onto a wonderful support group, though I do believe there are lots of folks here experienced with this, and this forum is superbly supportive, sometimes the more info and the more support, the better. It feels so humbling when you realize you can't "fix" this for your cat.
But...you can often do so much to return a quality of life to them, and to extend their life considerably (to me considerably means at least a year).
I've seen a number of members on this support list whose cats, with treatment and their owners loving care, gain another 3-4 years, some 6-7, and some are at 10 years and still going! I know that Frankie and I are shooting for her to be a 10 year gal or more
I found with Patrick, that what I believe made the most difference in how he did, was use of Calcitriol, a compounded medication that is a form of Vitamin D. Here is an article on it's use: http://www.marvistavet.com/html/body_calcitriol.html and I've used it with Frankie for over a year, Tyler for 2+ years now, and Tippy - recently diagnosed with Polycystic Kidney Disease (where to put it simply, cysts in the kidney - an inherited condition - pushes them into crf) - is also on this.
I firmly am a fan, if the cat is a candidate, in Calcitriol.
I also learned through experience with Tyler, how high bp can cause a detached retina and sudden bleeding into the eye. I am now a fan of a medication called Norvasc, as it got his bp down, and while he has only decreased vision left in the affected eye, it is clear, no blood remains visible, no further bleeding (though he did one more time when his bp spiked and he required an adjustment in his Norvasc dose).
I've learned that it is more important (imo) to get your cat eating then to insist on a prescription food the cat won't eat...that way leads to situations such as Hepatic Lipidosis...cats can not go without eating. No food=No cat.
I've learned that sometimes just assist-feeding for a day or two, was enough to jump start Patrick's appetite, and he'd begin eating again on his own.
I have come to agree with those that feel (in early crf) that paying attention to the phos content of the food (on a dry-matter analysis not an "as-fed" which is what the values are based on when printed on a cat food label) is more important than protein content. They will feel SO punky if their phos level is too high...so I used food lists that gave phos values, to choose foods with a phos content under 1% (per dry-matter analysis).
I use two lists - one is no longer very up to date, the katkarma lists:
both have a link to a briefer more updated version.
Kept up to date, though compiled for those with cats who have diabetes, is jmpeerson's lists:
These are wonderful as they are kept updated, and do list the phos and protein contents of a huge variety of dry/canned foods, prescription and non-prescription.
Okay...this is long enough. It's a start.