Old dog, elevated liver enzymes

Depending on where you are in the country I would consider getting a vet to ultrasound her belly and see what her liver looks like-they can check if the size is normal or not,and look for tumours etc so can give you an idea what you are dealing with.
if shes an easy going dog its non invasive and low stress procedure as they just lie down and the probe ran over their belly-some vets will lightly sedate with safe drugs if the belly is sore(where you are does matter as in rural areas it might be difficult to find a local vet who's good at scanning dogs livers)

However even if that isnt an option the fact you have found the problem before its causing serious issues.This is a good thing.

If shes a fussy dog then the prescription liver food from the vet may be difficult to convince her to eat but if shes not fussy it is worth giving.

Diet is important in liver disease.
The liver is a major organ in the body with a lot of jobs-breaking down drugs and toxins,processing fat and making some vitamins available to the body,making sure our blood can clot etc.

One of these is breaking down toxins and byproducts of food.Feeding hepatic supportive foods helps as these are foods designed to produce less toxins and ammonia so they take some of the pressure off a compromised liver and can delay the onset of clinical signs in the dog.

It is possible to feed a home cooked liver diet but that generally needs more research and time than the average person is happy to do.Mainly as the liver in theses situations needs specific things like changes in vitamins provided and unusual levels of different protein and low levels of fat that don't produce many byproducts.If you want to research it work away- I find that area a minefield and like the fact there are preprepared foods available.

If shes a very fussy little dog and her quality of life will suffer by changing her food then obviously do not,at 16 if shes fussy then let her just enjoy what shes likes rather than battling with her to eat a food she hates.Pick your battles quality of life is always the most important thing.

Other things that are known to help are milk thistle extract (yes its a heading towards homeopathy but the main ingredients in milk thistle are in several of the medical products as well as it works) and there are some veterinary supplement's as well like Hepatosyl plus(which incidentally contains milk thistle as well as some other drug's) and SAM-E whose ingredients that help the liver to recover and repair itself.

If shes showing clinical signs of course everything changes as different drugs can be used to make her more comfortable(your vet is the person to talk to in that case)

The liver can cope with up to 70 percent of its mass not working. At the moment as your dog is not showing clinical signs,so it is coping.

Diet and supplements should help.... but always keep in mind that at her age the underlying cause may be sinister.Its all now about making her quality of life as good as possibly for as long as possible.

Theres nothing wrong with continuing to just let her enjoy life as she is for as long as she is happy and comfortable...the above is just information you(or someone else reading this thread) might find useful.

Also this does show why taking bloods before anaesthetics is a very good idea.

The liver process' the anaesthetic drugs. In some cases putting all that extra drugs to process can tip a coping liver into failure... and a dog can have a struggling liver with no signs of it on a normal health exam.

Good luck with your girl eitherway and whatever you do decide well done on having a 16 year old pom and looking after her so well!thats a great age!

Below are the signs of a liver issues to look out for in dogs. I tried to put them in a click down spoiler link to save this being a monster post but it doesnt seem to want to work.

Loss of appetite

Vomiting

Diarrhea

Constipation

Increased water consumption and urination

Intermittent recurrent abdominal or gastrointestinal upsets

Progressive depression or lethargy...doesn't want to play anymore or refuses to go for walks

Swollen belly with a "fluid filled" look. This is also known as ascites and is actually fluid accumulation in the belly due to circulation alterations in the abdomen.

Pale gray feces. Bile pigments are what gives poop its characteristic brown color. If the liver isn't processing bile properly, the feces will not get its color.

Orange Urine. The improper processing of bile results in the excretion of bilirubin in the urine in high amounts, thus orange urine.

Jaundice, also known as icterus. Any pale or white skin or visible tissue takes on a yellow hue. Biliry pigments are accumulating in the body because the liver is not processing them.

Rare: bleeding problems. Many of the proteins required for proper blood clotting are created in the liver...remove these proteins and blood clotting decreases.

Hepatic encephalopathy, or severe neurological signs, behavioral changes, seizures, aimless pacing or circling, head pressing. May be associated with meal time.

Pain associated with the abdomen. This is due to the stretching of the liver capsule. May be noted when dog is picked up around belly or when probed (palpates) the abdomen

Chronic weight loss or wasting. The liver processes all the building blocks. If it fails to process, the body fails to maintain itself.