Some victims of cardiac arrest are simply not going to be resuscitated, no matter how hard you try. To figure out which victims are too dead to be saved, emergency responders look for five signs of irreversible death:
- Decapitation: Separation of the head from the body is the worst case scenario. There is currently nothing medical science can do to put a head back on a body and make it work. Doctors can reattach toes, fingers, arms, legs and even penises, but collar-level separation is a deal breaker.
- Decomposition: Once the flesh begins to rot, there's no possibility of resuscitation. A word of clarification, however: flesh can die in areas around the body even on a live person. That's why frostbite turns black. When we talk about decomposition being a sign of death, we are suggesting the entire body has begun to decompose and that the person is not breathing and the heart is not beating.
- Postmortem Lividity: When the blood stops flowing, gravity takes over. The Latin term is livor mortis or blue death. Blood settles in the lowest points of the body, which depends on the position it's in at the time of death. Most of our victims die in bed, so the purple streaks on their backs -- similar in color to bruises -- will follow the wrinkles in the sheets and show that blood hasn't been circulating for quite a while. Lividity can show up in as little as 15 minutes.
- Postmortem Rigidity: There's a reason dead people are called "stiffs." Once the last little bit of energy is used up in muscle cells they get stiff, until enzymes created through decomposition begin to break them down. The Latin term is rigor mortis or hard death. The chemistry is complicated, but rigidity starts soon after death and lasts for days, depending on heat and humidity.
- Burned Beyond Recognition: The last sign of irreversible death is very specific. It refers only to victims who die of burns. This sign is pretty self explanatory: once a victim is burned so bad that he or she is no longer recognizable, there's no chance of resuscitation.