Scar tissue (adhesions) is a good consideration. It generally doesn't show up on tests or films either. I know a fair about about adhesions because I've dealt with them for over 10 years. If they attach to intestines or other digestive structures, they can really wreak havoc with digestive functioning - and they cause a lot of pain too!
If scar tissue is the problem, and it's on her small intestines, that would certainly explain the vomiting. Small intestines aren't tucked into one spot, but rather hang fairly loosely in the abdominal cavity. If scar tissue attaches to them, it can cause the intestine to twist around it and block it off - sometimes temporarily until the intestines shift again, sometimes permanently and fatally unless surgically corrected. That twisting action stops waste from passing through, or slows it down enough that anything that goes into the mouth, comes right back up again.
When my dog nearly died this summer from being impaled on a plant stake, she had two major surgeries and a huge abdominal incision. Her surgeon told us that adhesions tend to not be a big problem in dogs (horses are apparently horrible) but all it takes is one strand of scar tissue in the wrong place to cause some pretty bad problems. If your surgeon can cut the scar tissue using a laparascope, that would be ideal as compared to another open abdominal incision. The idea being to keep tissue trauma to an absolute minimum so as to avoid a return of the adhesions. Not all practices have laparascopic equipment, so clarify any surgical methods with your vet. Although treating adhesions requires another surgery, I frankly think that is easier to deal with than a functional problem that medication just can't quite fix. Good luck!
Thanks! I will post it on there. After speaking to my vet yesterday, she said after testing her for everything possible and running film they believe that the pain is coming from scare tissue. It is only once in awhile when she has this pain. So, we are going to monitor and try to get her meds when she has an episode. She lost around 12 pounds in all of this so I have to get her weight back up. I also felt around on her scares from her stomach surgery and it feels like there is something metal up in her or staples inside of her. I know she had staples in which they took out. Would this be something else that I am feeling. Thanks! I will post on Ask a Vet Forum.
Bloat (twisted stomach) is a problem in large breed dogs. Generally, if it happens once, it's more likely to happen again. Really a heartbreaking problem especially when the dog is otherwise healthy. Did you ever get any answers about why the spleen is enlarged? I believe the spleen problem likely explains the low platelet count.
You really need to post this on the Ask a Vet Forum. MedHelp recently put a question limit on that forum, so you'll just have to keep trying until you get through. I sure wish they hadn't done that because that board was never all that busy, and Dr. Cheng is great at answering all questions on a timely basis.
You also might try a search engine like Google and use the words "dog" "bloat" and "enlarged spleen" as search criteria.