My plott hound/lab has the following symptoms:
Constant swallowing
Slightly enlarged heart
Fever
High white blood count
Heart murmer
Light vomiting, white/pink foamy fluid

She eats good, but does not have her usual energy

My vet is trying hard, but we can't figure out why or what to do.
She has been on 2 antibiotics and steroids (she didn't tollerate the steroids)
Let me know if anyone has had this happen to their dog.
Thank you!

I haven't experienced this sorry but I can give you a bit of info...

A high white blood cell count indicated infection of some kind.

Excessive swallowing or saliva production usually means either a bad/rotten tooth or a upset stomach.

A heart murmur will cause a bluish tinge to the gums and tongue, coughingm laboured breathing, and fatigue.

Enlarged hearts can be a symptom or cardiomyopathy... one of my mums Danes had this... there are a few symptoms sililar but also a few that don't line up...

There really isn't anything else I can say...
Has your vet done blood tests? Ultrasounds of the heart? Toxscreens?

If the answer is yes then there isn't much you can do apart from get a second opinion from aother vet.