Ⅶ. Study procedures (summary)

1. Written informed consent must be obtained before any study specific procedures are undertaken.

   Qualified participants were identified at the pre-anesthesia evaluation clinic or ward. The informed consents are obtained from the patient in the ward at night before the operation.

2. The process of the experiment (brief describe) In the preoperative waiting area, the patients are randomly assigned and divided into two groups according to the allocation sequence table (corresponding to 1:1 randomization) generated by the computer. The propofol group was both induced and maintained at an effect-site concentration (Ce) of 2.0-4.0 mcg/mL by a target-controlled infusion (TCI) system. The sevoflurane group was maintained via sevoflurane vaporizer between 1% and 3% (target minimum alveolar concentration of 0.7-1.3). During the operation, the dose of anesthetic drugs (propofol/fentanyl /remifentanil and sevoflurane/cisatracurium/rocuronium) are adjusted to maintain the mean arterial pressure and heartbeat fluctuations within 20% of the baseline value and Entropy (or BIS) value at 40-60in both groups. The following patient data were recorded, the type of anesthesia, sex, age at the time of surgery, preoperative Karnofsky performance status (KPS) score and functional capacity, the postoperative complications within 30 days (according Clavien-Dindo classification), ASA physical status scores, tumor marker ,tumor size, intraoperative blood loss/transfusion, duration of surgery, duration of anesthesia, total opioid (remifentanil/fentanyl) use, postoperative radiation therapy, postoperative chemotherapy, postoperative concurrent chemoradiotherapy, the presence of disease progression, and 6-month, 1-year, 3-year and 5-year overall survival and Karnofsky performance status score were recorded.

During the operation, the dose of anesthetic drugs (propofol/ fentanyl /remifentanil and sevoflurane/ cisatracurium/ rocuronium) are adjusted to maintain the mean arterial pressure and heartbeat fluctuations within 20% of the baseline value and Entropy (or BIS) value at 40-60in both groups. The following patient data were recorded, the type of anesthesia, age at the time of surgery, preoperative Karnofsky performance status (KPS) score and functional capacity, the postoperative complications within 30 days (according Clavien-Dindo classification), ASA physical status scoress, tumor marker , tumor size, intraoperative blood loss/transfusion, duration of surgery, duration of anesthesia, total opioid (remifentanil/ fentanyl/ propofol) use, postoperative radiation therapy, postoperative chemotherapy, postoperative concurrent chemoradiotherapy, the presence of disease progression, and 6-month, 1-year, and 3-year overall survival and Karnofsky performance status score were recorded.

Inclusion Criteria:

1. Twenty to eighty-year-old.
2. ASA class I-III.
3. Patients undergoing elective craniotomy for primary ovarian tumors under general anesthesia.

Exclusion Criteria:

1. Severe mental disorder
2. Poor liver function
3. Pregnant or lactating women
4. Morbid obesity
5. Have a history of allergy to any drug used in this study
6. Non-primary ovarian cancer surgery
7. Undergoing ovarian cancer pathological section surgery
8. Patients with incomplete medical records
9. Combined with other surgeries, emergency surgeries
10. Concomitant patients with other non-ovarian cancer therapy
11. Patients receiving palliative treatment after ovarian cancer surgery
12. During the maintenance period of anesthesia, propofol or sevoflurane should not be used as anesthetic drugs
13. Intraoperative combined use of multiple anesthetics (such as ketamine, dexmedetomidine, other inhalation anesthetics)
14. Those diagnosed with benign tumors before and after surgery
15. Patients with metastases to the ovary