In France, death remains taboo. Some may be uncomfortable talking about it, others are on the contrary intrigued… In any case, it is a natural physiological process widely studied by researchers and scientists around the world.Death is the interruption of life and the biological functions that characterize it. It is also the loss of consciousness, of personality, of everything that makes us a sensitive and social being.defines Valérie Mils, Lecturer in cellular biology – developmental biology center – Paul Sabatier University in Toulouse. Death is a process that takes its time since, except in cases of violent or accidental death, it is the inevitable outcome of the irreversible aging of our organs.“. But which organ “gives up” first? And last?
“The newly deceased body is like an orchestra where each musician plays his part without a conductor. What follows is a cacophony that no longer resembles the symphony that the players should produce.“, she explains on the occasion of an exhibition at the Toulouse Museum. “Uonce the blood circulation is interrupted, during the natural death by cardiac arrest, the organs are no longer irrigated and the activity of their cells will gradually stop. Cardiac arrest causes the failure of the other organs one after the other. Death is not an instantaneous phenomenon: not all organs die at the same time. This is what makes it possible to transplant organs even though the donor is dead. This stopping of metabolisms, that is to say of all the functions of the organism (heartbeat, blood circulation, breathing, interneuronal communication, etc.) will have consequences on the state of the body which will progressively deteriorate”, explains Dr Michel Sapanet, director of the Poitou-Charentes Institute of Legal Medicine.
As we will have understood, (natural) death is therefore not instantaneous and it would seem that it follows a defined chronology.
► It often begins with cardio-respiratory arrest (heart failure) which prevents the oxygenation of the blood and the irrigation of the organs.
► The brain can still function for several minutes (this is why since 1968, cardio-respiratory arrest is no longer considered sufficient to declare the individual dead and the criterion of death is today the cessation of brain function or “brain death”).
► After brain death, the progressive and desynchronized death of the different organs begins:
- The first cells to die are those lining our blood vessels
- The kidneys, pancreas and liver are altered by the digestive enzymes they produce and follow in less than thirty minutes (in the case of organ donations, they are kept artificially active)
- Muscles that contain large energy reserves last a little longer.
Finally, skin, bone and corneal cells are those that resist the longest, up to 1 or 2 days.