I have been a member of /r/natureismetal and I can tell you without a doubt that most prey are eaten alive. Even baboons and chimps eat their prey alive.
> The HPP seafood meat extraction process involves pressure levels around 3,000 – 4,200 bar (44.1 – 60.3 kpsi) and holding times between 45 – 90 s. Shucking with seawater (4 – 25 °C) improves flavor as high pressure infuses salt into the lobster meat. HPP shucking should occur with live lobsters
What I've read over the years is that when a submarine implodes from external pressure, the implosion happens SO fast that the human occupants are never aware of it. [0]
That sounds to me like the one time I was ever under general anesthesia: One instant I was chatting with the medical staff as they were putting me under, the next instant I opened my eyes and saw my wife standing over me in the recovery room.