The change profiles of indices derived from pEEG such as phase-amplitude coupling and bicoherence based on individual general anesthetics in children have not been examined in previous literature. Whether those indices have the abilities to predict individual drug-related anesthesia depth in children need to be explored.

The need to maintain a proper depth of general anesthesia during pediatric surgery is an important aspect of anesthesiology. An inappropriate anesthesia depth increases the risk of intraoperative awareness or delay in recovery in children undergoing surgery. Current modalities for anesthesia depth monitoring showed limited accuracy in children. The electroencephalogram (EEG) can be analyzed in its raw form for characteristic drug-induced patterns of change or summarized using mathematical parameters as a processed electroencephalogram (pEEG). The change profiles of indices derived from pEEG such as phase-amplitude coupling and bicoherence based on individual general anesthetics in children have not been examined in previous literature. Whether those indices have the abilities to predict individual drug-related anesthesia depth in children need to be explored.

Inclusion Criteria:

• patients aged 0-18 years, American Society of Anesthesiologists Physical Status I-II, scheduled for elective surgery in Peking University First Hospital.

Exclusion Criteria:

• Preterm patients;
• Height and weight not within the standard ranges for respective ages;
• Surgery for head or heart;
• Patients with muscular, neurologic or psychiatric diseases;
• Patients with Congenital anomaly or hereditary diseases;
• Patients with medication abuse;
• Allergy to medication including propofol, sevoflurane, and ketamine;
• Allergy to beans;
• Refusal to participate the study by guardians.

patients aged 0-18 years, American Society of Anesthesiologists Physical Status I-II, scheduled for elective surgery in Peking University First Hospital