The aim of this study is to estimate blood pressure in pediatric patients using a non-invasive electrocardiogram (ECG), photoplethysmograph (PPG), and an accelerometer on the chest.

Blood pressure is measured by an automated oscillometric device or arterial waveform from IntelliVue MX800 Bedside patient monitor (Philips Healthcare, Amsterdam, Netherlands).

Following parameters will be measured by non-invasive electrocardiogram (ECG), photoplethysmograph (PPG), and an accelerometer on the chest and will be used to estimate the biosignal derived blood pressure.

1. PAT(time between R peak of ECG and beginning of the pulse of PPG)
2. PEP(time between R peak of ECG and peak of accelerometer signal)
3. PTT(PAT-PEP)

The algorithm of the biosignal derived blood pressure will be made using the MATLAB 2016b(Mathworks, Natick, MA) program.

The agreement between the non-invasive blood pressure and the biosignal derived blood pressure will be analyzed using Cohen's Kappa or Bland-Altman plot.

Inclusion Criteria:

• ASA(American Society of Anesthesiologist) Class I, II
• Scheduled for elective surgery under general anesthesia

Exclusion Criteria:

• History of cardiovascular disease
• History of thoracic cavity disease
• Unable to measure blood pressure

ASA class I, and II pediatric patients (<12 years) scheduled for elective surgery under general anesthesia

We art not planning to share individual participant data available to other researchers