UK ambulance crew SOP is to resuscitate until reviewed by a doctor, unless putrefying, decapitated or charred. Sometimes they don't try very hard, I suspect, but that's probably hard in an aisle with 300 people watching.
Things may have changed since I was working as a UK paramedic but I was certainly able to CONFIRM death and either not start CPR or terminate resuscitation attempts subject to certain criteria being met.
Whilst having never responded to an emergency on Delta, I have on BA/VA/Spirit and without fail having been given total support (and appreciation), from the crew. VA have on (all 3!) occasions have shown their gratitude on board and afterwards from 'HQ' very generously; However I answer the PA call because I'd want someone to do the same for a member of my family, not because of what I might get in return.
HTC
HTC