[esseph]

Can you explain?

[Dansvidania]

Not op, but imagine doing cpr to someone for more than an hour (btw this means multiple people taking turns because cpr is exhausting) and at some point there is a sign of feeble heart contractile activity (and hence life)

It must have been a very emotional moment for the rescuers and parents if present.

Edit: corrected typo

[rsync]

An hour of cpr in an ALS scenario almost certainly involves a Lucas device:

https://en.wikipedia.org/wiki/LUCAS_device

… which are commonly carried in ambulances.

[Dansvidania]

TIL! thanks!