The most dangerous complication after craniocerebral surgery is postoperative intracranial hemorrhage, which includes bleeding in the operation area caused by incomplete surgical hemostasis and decompression hematoma caused by removing a huge tumor, as well as cardiovascular and cerebral vascular accidents occurring in the perioperative period, such as bleeding from stroke. If the amount of bleeding is small, the patient’s condition will not be too dangerous, and conservative treatment will be given, and the hematoma will be slowly absorbed by itself. If the amount of bleeding is huge, the patient’s condition will be very dangerous, and the patient may become comatose, or even have dilated pupils, loss of light reaction, or brain herniation, which is life-threatening and requires urgent reopening hematoma removal. Hematoma can also lead to neurological dysfunction, causing paralysis of limbs, seizures, and even long-term coma.