A coma from a brain hemorrhage is the absence of consciousness. The definition of coma in clinical practice is mainly assessed based on the Glasgow score, and a patient is assessed as comatose if the Glasgow score is ≤ 8. Coma is mainly due to the brainstem function being affected, thus affecting the waking function, and the brainstem damage is mainly caused by a relatively large amount of brain hemorrhage, thus causing compression of the brainstem. Therefore, for patients in coma, the first step must be to actively control the increased intracranial pressure caused by brain hemorrhage, such as surgically removing the intracranial hematoma to maintain normal intracranial pressure. However, if the bleeding volume is large, even after early active removal of the hematoma, the patient may still have difficulty in waking up, which means that it is difficult to become conscious, mainly because the brain hemorrhage causes damage to nerve cell function, and the nerve cells are non-regenerative, so it is easy to cause coma.