Thanks macoduck and Time4ANap!
Brisa was normal before this sudden onset of vomiting, now seven days ago. I am concerned that she may have eaten non-food items, however it has not been in her nature to try. She was referred to a specialty vet hospital two days ago where she now remains. She is now on an IV.
I first suspected an obstruction, but that was nearly ruled out early by x-rays. However, a dilated esophagus was clear. The vet then suspected myasthenia gravis, considered the most common cause of canine megaesophagus. The vet immediately began treatment for myasthenia gravis, but Brisa did not respond as she should. So the vet then, reluctantly due to need for anesthesia, performed the endoscopy, thereby confirming no obstruction but finding a "bruised/reddish" appearance to the back of her stomach. The vet took a sample of her stomach for biopsy with earliest possible results tomorrow. At this time, cancer is not suspected. I may try to consult Dr. Cuoto.
