Brain-dead people were declared dead in foreign hospitals and stopped medical treatment. In China, cardiac death is regarded as death and brain death. As long as the family members do not give up medical treatment, the hospital will continue to use ventilators and drugs to maintain signs of life until the patient dies of heart and lung organ failure.
The human brain consists of six parts: medulla oblongata, pons, midbrain, cerebellum, diencephalon and telencephalon. The medulla oblongata, pons and midbrain are collectively called brain stem. The respiratory center of human body is located in the brain stem, so the impairment of brain stem function will directly lead to the cessation of respiratory function. Cells in some parts of the human body can recover their functions through regeneration after injury, but nerve cells are different: once they are necrotic, it is difficult to regenerate.
Many countries used to regard "cardiac arrest" and "disappearance of breathing" as the criteria of death. However, with the development of medical science and technology, through a series of drugs and advanced equipment, patients' vital signs such as heartbeat, respiration and blood pressure can be reversed or maintained for a long time.
However, if there is structural damage to the brain stem, no matter what medical measures are taken, the patient's life cannot be saved. Therefore, brain death is more scientific, more reliable and more standardized than cardiogenic death.
Extended data
In the impression of most people, the boundary between "life" and "death" is very clear, but now under the guidance of science and technology, this boundary is becoming more and more blurred and difficult to define.
The earliest way to judge whether a person is dead is to shout the patient's name three times, or stick a mirror under their nose to see if the mirror will produce fog, and clamp the nipple with pliers and other verification methods. However, under the influence of this empiricism, there have been many cases of "buried alive".
Cardiac arrest means death occurred in19th century. With the emergence of artificial respiration and defibrillators, people introduced the concept of "brain death", which has been used ever since.
2065438+In April 2009, researchers from Yale University successfully revived the pig brain four hours after its death, and maintained it for at least six hours. This study was published in the April issue of the famous scientific magazine Nature, which caused an uproar and challenged the standard of "brain death".
In fact, this so-called resurrection is not what we understand. Scientists have restored the brain circulation of pigs by delivering oxygen and nutrition to brain cells. Cells have metabolic function and respond to drugs. Some neurons also produce electrical signals. However, the pig did not regain consciousness, and there were no orderly electrical signals in the brain.
Undeniably, with the help of technology, the clear and thin boundary between life and death in the past is becoming wider and blurred. The decision of "brain death" will not be the end of mankind. The new rules are being worked out and will be changed in the future.
Baidu encyclopedia-brain death