Scientists were able to conduct for the first time the study of the features that accompany the death of the human brain at a time when this event is already irreversible. Observation of the phenomenon was carried out in several non-reanimation patients of one of the hospitals. The researchers shared their findings in the journal Annals of Neurology.
For many years scientists have been trying to find out in detail what happens to the human brain at the time of his death. Despite earlier discoveries in this field, progress in the research of this direction has somewhat stalled. First of all, because of the inability to control the very process of human death. One of the main duties of physicians is to avoid death as much as possible, so specialists are doing their best to this aspect, and not to any monitoring there.
As a result, most of our knowledge about what is actually occurs with the brain during the transition from the living to the inanimate state, are based only on the results of experiments on animals, as well as on stories and observations of reanimated patients who were actually on the verge of this irreversible event.
The poor killed little animals have made a significant contribution to understanding those conditions and processes that are accompanied by the death of the brain. Thanks to them, we learned that within 20-40 seconds after the onset of oxygen starvation, the brain enters the so-called "energy-saving regime" state, becoming electrically inactive.
A few minutes later, in the absence of oxygen, the brain begins to break down, as the process of splitting the ion gradients of its cells begins, and the wave of electrochemical energy, called depolarization (or "brain tsunami"), spreads through the entire cortex and its departments, causing irreversible damage.
However, an international group of researchers led by a neurologist Jens Dreyer from the University of Charite in Berlin managed to complete a real discovery. Scientists not only were able to observe for the first time the state of the brain at the time of cessation of its vital activity, but also found that the "brain tsunami", that is the end point after which the brain finally dies, can be stopped. Such a conclusion was made on the basis of a study of nine non-reanimated patients with monstrous brain traumas.
"Soon after the blood supply stops, the depolarization spreads, indicating the release of accumulated electrochemical energy in the brain cells, after which toxic processes begin to start, eventually leading to death, "explains Dreyer.
" It is important to add that this process is reversible, up to the point of recovery of blood circulation. "
By resorting to technologies, neuromonitorolin ha and using subdural electrodes as well as intraparenchymal sensors, scientists came to the assumption that the spreading wave of depolarization does not represent the final process of brain death as long as there is a possibility of restoring blood supply and oxygen supply.
"Anoxia (absence of oxygen in tissues ) is completely reversible without any visible signs of cell damage, if the oxygen level recovery occurs before the so-called non-return point, when under the influence of a permanent depot yarizatsii started the process of neuronal death, "- the authors explain in their paper
For patients with a high risk of injury or death due to brain ischemia or any other type of stroke, this discovery may one day be a lifesaver.. Nevertheless, scientists explain that there is still a lot of work to be done so that doctors can use the methods of therapy developed on the basis of this discovery.
"To date, there are no direct ways of using this discovery to save and treat patients," – commented Dreyer, adding about the obvious need for new research and observations in order to fully understand the question.
"Understanding the processes involved in the propagation of depolarization has a fundamental yuschee importance to develop additional strategies and techniques designed to extend the survival of nerve cells in violation of perfusion (blood supply to the right) of the brain. "