Hi there and thank you for your question. My name is ***** ***** I am a licensed, internship-trained veterinarian with 11 years experience in general medicine and emergency and critical care medicine and I would be happy to assist you. Please be patient as there may be slight delays in responses as I research your pet's issue.
I am so sorry to hear this! Unspayed females are at great risk for developing pyometra later in life, and then having to have emergency surgery to remove the uterus. Unfortunately, undergoing anesthesia when there is a serious infection in the body and the dog is geriatric is risky, and there can be complications. I suspect that your dog may have experienced a blood clot in the brain during the procedure, or it is possible that there was a brain tumor that was not causing a problem, but then the anesthesia somehow made it worse. Some of the symptoms, though, sound like back pain- the discomfort when going to the bathroom, the heavy panting, and losing the ability to stand and walk. The steroids should have helped that if they were going to, so there isn't a lot more that can be done by a regular vet except give pain medications such as gabapentin. If you are willing, I would see a neurologist for an MRI to see what is going on in the brain... that's the only way to know. If that is not an option financially, I would ask your vet to keep the dog on steroids for a month and go from there. This does not sound like a good situation, and I am so sorry.
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