Gabriel never did need to be syringe fed, but if you want to give him more nutrients, then do that. I use Oxbow Carnivore Care and Oxbow Critical Care (always have it on hand), mix it with butternut squash babyfood and bee pollen. Bee pollen is great for them. But a slurry of greens and bee pollen will help him, too. I could never do anything with Gabriel but keep watch on him as if it pops, he would have bled to death, instead, he absorbed it 2 years after being diagnosed and it's gone. So hopefully it heals on it's own. Did the vet say what type of surgery he'd be wanting to do? Is he 100% sure it's an aneurysm? Did he send the blood to the lab to be determined? My vet took liquid from the aneurysm (I was afraid, afterwords, that it would pop and sent it to the lab, that's how we knew it was an aneurysm. Just love your little on all the time and getting him something he won't fall from is great. You can't stop him from bobbing, it's spring in their mind and drives them nuts.