Forehead sensor can predict the more accurate fluid responsiveness than finger sensor in children

The investigator hypothesized that the forehead sensor can predict the fluid responsiveness more accurate than the finger sensor in pediatric patients.

Inclusion Criteria:

• pediatric patients undergoing general anesthesia for neurosurgery, major abdominal surgery, and cardiac surgical procedures.

Exclusion Criteria:

• preoperative Ejection fraction <30%
• underlying lung disease
• cardiac arrhythmia