@MavB_Ver If tissue damage is no issue, then yes it is feasible. The limiting factor is that most internal systems stop with the loss of nerve impulses. Most importantly the heart and lungs. Some cells can go a surprisingly long time without resupply from the bloodstream. However, the brain cells have high nutrient demands and will begin to suffer irreversible damage at around 5 minutes. Permanent brain damage will begin at around 15 minutes.
Coming back from "clinically dead" is not impossible. Depending on the situation, it can even be simple. I've been clinically dead, when my heart stopped after a bad reaction to morphine. It can definitely be done.
There have been some theoretical techniques for repairing extreme battlefield trauma around for a while now. Like deliberately stopping the heart to stop a bleed (internal or external) then restart it. Or for a damaged heart replacing it with a mechanical version and just injecting the make-up blood volume from packs. Once it starts beating the person should come back to life. There are many factors to make it unfeasible but it is all theoretically possible.