After giving this more thought, I believe that
FD was absolutely dead in his driveway on Tues.
With supplemental oxygenation and chest compressions first responders got his heart working (slight pulse) but continued supplemental oxygen. It took some minutes for
his heart to respond. Even with top notch medical care since Tuesday there's been substantial trauma done to his whole body, his brain ( probably severe swelling/edema, heart
may continue to have problems even in the future, neurologic problems eyes can be damaged permanently, deafness can be an aftermath as well as organic psychosis in the future. Loads of problems even if he comes out of this immediate situation.
I'd encourage you to read the article I posted
above to get a feel for what a body goes through.
Honestly I hope he goes quickly and doesn't have to endure all the potential problems caused by his actions.