It is a kidnapped Tony fic. It was on ao3 and it was multichaptered. I remember at the beggining Tony getting in his car with Happy for a busineaa meeting, he was tired and he dozed off for a little. But then the cae gets attacked and someone kidnaps him.
The team searchs for him for so long and they do find him but Tony was in a bad shape. The rest of the story was focusing on his recovery.
I think it was a Stony fic. And I remember a lot of medical jargon. Like he was bradycardic for some time. Bruce used AED pads/deffibrilators to keep his heart beating when they first got him back.
I don't remember who kidnapped him but there is a possibility of the fic contains non-con.
I would be so happy if you could gind this fic or remember something about it tbat I cant and tell me. Tnank you in advence.