Hi,
I am so sorry you are at the point where you have to make a difficult decision. I would like to refer you to a blog I wrote addressing this topic. I hope it helps.
http://gardneranimalcarecenter.blogspot.com/2009_04_01_archive.html
Our thoughts and prayers are with you and your family!
My husband and i met with our vet this afternoon and he suggested we take him home a couple of days and try Sulcrafate,Metroniazole and pepcid to try and get the diarrhea stopped. He said there was also a dog stomach virus running around and he said he had already seen 2 dogs today with it.He said it could be that or the kidney failure.
We told him it was hard for us to hear our dog moaning when he moves.Our dog isn't throwing up but every so often,i have managed to keep that under control by giving him Tums everyday,and he does good on that. He has started eating again after i started giving him the Tums,he eats dogfood for a solid 5 to 7 minutes at a time,usually at night.
His values are really bad on his kidneys and the vet says he doesn't have much time left. We just don't want him to suffer,he has been in pain from an autoimmune disease for 2 years along with the Kidney failure.
Knowing when it is time is a hard difficult decision to make. It really comes down to what you see with your pet along with your veterinarian's advice on the prognosis of the disease - in this case kidney failure. Your description sounds as if the prognosis is very poor. The simple way to look at it is deciding when there are more bad days than good. When he is having more bad days than good days and the problem cannot be improved/corrected, it's time. Yes, we all have bad days - so saying it's time is not a definitive knowledge - it's a sense that the quality of life is no longer there and really has no chance of returning. I am sorry you have to go through this, but I admire your courage to reach out and think about making that decision to euthanize - a self-less act to help a loved pet.