replied 8 years ago.
The reason I asked about a urinalysis done previously, is that it is a more accurate indicator of kidney function than bloodwork. It takes at least a 75% reduction in kidney function before it will affect blood values - that's why you can donate 1 kidney, because even with only 1 kidney, you still have as much as twice the kidney function you need.
So, without a urinalysis from before, all we can say is that she had at least 25% of her kidney function at that time.
The numbers you gave initially (143 and 7.9) are definitely elevated, and pretty serious. However, what I find more concerning is that the numbers are increasing rather than decreasing. This indicates to me that the damage is continuing.
Generally, acute renal failure, if they survive the initial insult, has a better long term prognosis than chronic renal failure. Depending on what that initial insult was - for instance, anti-freeze poisoning causes acute renal failure, but has a very poor prognosis. On the other hand, infections and other toxicities can cause acute damage, but if promptly and appropriately treated, can recover and survive, although they may have long term kidney damage.
Without knowing the cause, it is impossible to say whether her chances for recovery are good or not. A lot depends on what treatment she is receiving. If she is on IV fluids and is still not improving, then her chances are much worse. If she stops producing urine at all, or in very small but dilute amounts, that's a very bad sign. On the other hand, as long as she is urinating, whether it be large amounts that are dilute, or small amounts that are concentrated, that is good.
If she is not on any sort of fluid therapy (intravenous would be much preferred, but even subcutaneous fluids are better than nothing), then it is much harder to evaluate. The fact that her condition, based on her kidney values, seems to be getting worse is bad, but we have no way then of knowing whether she would or would not respond to treatment.
I usually tell my clients who bring in a pet with elevated kidney levels to give the pet 24-48 hours of aggressive treatment - i.e. intravenous fluid therapy. If we don't see improvement in that time, or if the condition continues to worsen despite treatment, then I would usually advise to at least consider letting them go. I say usually, because there are always exceptions - such as if we are dealing with a serious kidney infection and waiting on response to antibiotic treatment, or something like that. But without those mitigating factors, lack of response or worsening despite aggressive fluid therapy is a pretty strong indication that the pet is not going to recover.
As for what to feed. Well, diet does matter, to a point. Because metabolizing proteins is hard on the kidneys, ideally a low protein diet should be fed. The more protein the dog is given, the more work the kidneys have to do. HOWEVER, if she is not eating at all, her body will start to break down stores from her own tissues, and the by-products of that catabolism are even harder on the kidneys. So, while it is important that she eats an appropriate kidney diet, it is more important that she eats at all.
I would try to stay away from the cat food, just because cat diets are generally very high in protein. Hotdogs are also probably not the best source of protein. Ideally, we want to not only minimize her total protein intake, but make sure that the protein she DOES get is high quality. If you're going to tempt her with people food, steak or chicken breast would be a better option than hotdogs. On the other hand, if hot dogs, or even cat food, are ALL she will eat, then better she eat something than nothing. I would just try offering her the better options first, only going to poorer options as a last resort.
Also, I would recommend asking your vet about nausea medicine and antacids. Often, dogs in renal failure won't eat because they are nauseous due to the high levels of toxins (BUN and creatinine, for instance) in their blood that the kidneys are no longer able to filter out sufficiently. By giving medication to reduce that nausea, she may be more willing to eat. And they can also develop gastric and oral ulcers secondary to the kidney disease (one reason pets with kidney disease often have bad breath), so medications such as Pepcid or Tagamet can help.
I hope this helps and answers your questions sufficiently. If you have additional questions or need more info, please let me know. Also, this was all off the cuff from my daily practice, so I don't have authoritative sources to refer you to off hand. However, if you would still like those references, let me know and I will see what I can find for you.
PS Nope, didn't miss your response. Just long-winded when I get going. Something my techs are constantly complaining about - especially when I run them late at night cuz I talk too much. ;-)
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