For patients who undergo craniotomy, there are many surgical risks, including preoperative risks, intraoperative risks, and postoperative risks, as follows: I. Preoperative risks: When patients undergo craniotomy, they have to undergo general anesthesia, and there is a risk of anesthesia accidents. II. Intraoperative risks: During surgery, patients may experience hemorrhage due to unforeseen circumstances. For elderly patients, there is serious cardiopulmonary dysfunction before the operation, therefore, during the operation, it may lead to serious myocardial ischemia as well as myocardial infarction, resulting in cardiac arrest. In addition, it may lead to the patient will develop pulmonary decompensation, as well as various unpredictable risks, and some patients may even develop severe multi-organ dysfunction. Third, postoperative risks: In the postoperative period, it may lead to various serious comorbidities and complications, such as pulmonary infection, hypoproteinemia, and deep vein thrombosis of the lower extremities.