Coma in brain hemorrhage patients is mainly due to the relatively huge damage to the nerves, which results in coma. The first aspect is that the brainstem reticular nerve fiber center can maintain a waking state, that is, it can do some basic physiological activities, such as eating, urinating and defecating, breathing and so on. The second aspect is that the brain as a whole will maintain an advanced life support, such as what kind of meal to eat, whether it is salty or light, to urinate or defecate, all are consciously controlled and so on. Therefore, if the brain hemorrhage is relatively large and damages various nerves, it will result in not being able to eat, not knowing how to eat, etc., and then it will gradually become severe and cause a coma.