Brain Death: Electroencephalogram or a Cerebral Blood Flow Study

Of all deaths in the United States, 1% to 2% are due to brain death ("organ donation and brain death"). This means that approximately 6,411,258 people died of brain-related events. Brain death is a controversial topic in the medical field for many years. I do not want my family to tell the hard work that my loved ones can not survive. In most cases, patients can not survive. However, the state of a person depends mainly on the type of injury that occurred.

Cerebral hypoxia - refers to a situation in which brain oxygen supply decreases even with adequate blood flow. Complications of drowning, strangulation, suffocation, choking, head trauma, carbon monoxide poisoning, general anesthesia may lead to cerebral hypoxia. Symptoms of mild cerebral hypoxia include inattention, lack of judgment, loss of memory, and loss of motor coordination. Brain cells are very sensitive to oxygen deficiency and begin to die within 5 minutes after oxygen supply is blocked. If the hypoxia lasts for a long period of time, it also causes coma, seizures, even brain death. During brain death, cardiovascular function is maintained but there is no measurable activity in the brain. Breathing needs life sustaining

Normal cerebral blood flow is about 50 to 60 ml / 100 g / min, and it varies in different parts of the brain. With ischemia, the brain self-regulating mechanism compensates for the decrease in cerebral blood flow due to local vasodilation and increases the extraction of oxygen and glucose in the blood. When cerebral blood flow falls below 20 ml / 100 g / min, electrical silencing occurs and synaptic activity is greatly reduced to preserve accumulated energy. Cerebral blood flow of less than 10 ml / 100 g / min can cause irreversible neuronal damage. When microscopic thrombi are formed, these nerve injuries occur. This is caused by the activation of destructive vasoactive enzymes released by ischemia-induced endothelial cells, platelet cells and nerve cells. In one hour of hypoxic ischemic injury there will be an ischemic penumbra with automatic adjustment ineffective

The causal mechanism is the lack of blood flow in the brain when awaking. After getting asleep, it will take some time for the brain to return to normal. This "kickback device" performance is a gradual increase in cerebral blood flow to normal levels. It starts with primitive / ancient brain parts such as the brain stem and thalamus, and spreads to the anterior cortical region about 15 minutes afterwards. As demonstrated in the study of transcranial Doppler ultrasound examinations, the ability to carry out basic cognitive tasks is influenced by the cerebral blood flow in these areas. In-depth study