Brain death is also clinically known as vegetative state, which means that the patient’s brain cells are damaged, which then leads to insufficient blood and oxygen supply to the brain and apoptosis of brain cells, which does not affect the beating of the heart. If there is a ventilator in the hospital, extracorporeal circulation support and drugs to maintain water and electrolytes, the patient can survive for a long time, that is, the patient can be in a vegetative state for a long time with the support of various medical conditions. However, if the patient is not living in the hospital, the patient may die soon after brain death due to damage to the heart muscle, lack of oxygen and insufficient blood supply to the heart, so whether the patient can survive long after brain death depends mainly on the external medical conditions.