How to tell if it is the end of your cat's life.
How to Test Cat's Vital Signs at Home
There's an app that describes the cat's heart. It's from Google Play called Cat Heart Interactive. There's another app in iTunes that helps you track a dog's breathing rate but I don't see that it can be adjusted for cats. But I could be wrong.
Website with useful information on cat's breathing rate and how to check and why it's important.
Yet another site that nicely details how the kidney works and what happens when something goes wrong. Read this information to better understand the need for kidney protection and support. I suggest giving vitamins and supplements that Myrna takes for kidney support. The information is in the Med tab at the blog here and in Notes in Facebook "What Does Myrna Take".