Please help me save Loki

I'm sorry, I hate asking people for help but if anyone can help me save my best friend, I would be eternally grateful! He started acting strange yesterday evening and so I took him to the emergency vet, they found an undiagnosed mass in his abdomen that had ruptured, and he was bleeding internally. I had to empty my bank account, max out every card I have and open a new line of credit just to pay for the care he has already received. I literally have nothing left. I have nothing of value left to sell and I just spoke with his Dr. and he said it will probably be another 10k in expenses. Loki is my best friend and the sweetest most loving boy I've ever had the pleasure to meet. I can't lose him, please if anyone can find it in their hearts to help him, please do so.