system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What are the physical signs of a clinically dead human that indicate they are beyond saving via CPR or defibrillation

Let's say a disaster happens and life-saving resources are scarce. Rescue workers and paramedics must choose which clinically dead victims they apply their time and strength on. What are the signs that indicate there's is/isn't a chance?
gpt
One of the biggest situations that every emergency personnel dreads is having to play god.

Situations you are talking about are what we called MCI's (Mass Casualty Incidents), where there are more patients than the available units can handle.

Under normal circumstances, what happens is, the technicians on scene begin to triage the patients based on four colors; Green, Yellow, Red, Black


Green = Stable patient, can walk on his/her own, minor injuries, nothing life threatening (cuts/bruises)

Yellow = Slightly unstable patient, probably can't do much on their own, significant injuries, although maybe not life threatening (broken bones)

Red = Critical patient, requires immediate interventions, highest priority to be treated (active major bleeding)

Black = Dead. No pulse, no response, no attempts to resuscitate, as the resources can be used elsewhere.