Feasibility Study of Non-Contact Imaging-Based Physiological Monitoring in the Operating Room
Conditions: Cholecystitis, Liver Neoplasms, Cholelithiasis, Inguinal Hernia
Sponsor: Taipei Veterans General Hospital, Taiwan

Feasibility Study of Non-Contact Imaging-
Based Physiological Monitoring in the 
Operating Room 
 
NCT Number: Not yet assigned 
Unique Protocol ID: 2025-07-019CC 
Sponsor: Taipei Veterans General Hospital, Taiwan 
Principal Investigator: Hui-Hsuan Ke, MD 
Document Type: Study Protocol and Statistical Analysis Plan (SAP) 
Version: 1.0 
Document Date: January 1, 2026 
 
 
 
 
 
 
 
 
 
 
 
 
 

1. Background and Rationale 
Perioperative vital sign monitoring traditionally relies on contact-based or invasive 
devices, such as ECG leads, blood pressure cuffs, and pulse oximeters. While widely 
used, these devices pose risks of cross-infection and potential skin injury to vulnerable 
populations, and their wires can restrict patient mobility. Non-contact sensing 
technologies, including remote Photoplethysmography (rPPG), offer a promising 
alternative. Our team has previously validated this technology for pulse and respiratory 
rate detection in clinical environments. This study aims to further evaluate the feasibility 
and accuracy of this non-contact imaging technology for monitoring heart rate (HR), 
blood pressure (BP), and blood oxygen saturation (SpO2) within the dynamic 
environment of an operating room. 
 
2. Study Objectives 
Primary Objective: 
 Evaluate the feasibility, stability, and accuracy of the non-contact imaging-based 
physiological monitoring system during surgical procedures (including induction, 
surgery, and recovery) compared to clinical standard monitors. 
 
Secondary Objectives: 
 Optimize algorithms for enhanced adaptability in dynamic surgical settings. 
 Explore potential applications for specific clinical groups, such as patients with fragile 
skin. 
 
3. Study Design 
This is a single-center, prospective, exploratory observational study using a within-
subject comparative design. Approximately 315 adult patients undergoing elective 
surgery under general anesthesia will be enrolled. Each participant will simultaneously 

receive both non-contact imaging monitoring and standard clinical monitoring for real-
time data comparison. No randomization or blinding is involved. 
 
4. Study Procedures and Methods 
Informed Consent: Obtained preoperatively. 
Investigational Device: rPPG software installed on a Logitech C930 (Windows), iPhone 
16 Pro Max (iOS), and Samsung Galaxy S24 Ultra (Android). 
Reference Devices: Masimo Root platform, SedLine O3 regional oximetry, and Radical-
7 pulse oximeter. 
Data Collection: Continuous facial video and physiological signals will be captured 
throughout the perioperative period (from induction until patient transfer to the recovery 
room). 
 
5. Eligibility Criteria 
Inclusion Criteria: 
 Age ≥ 18 years. 
 Scheduled for surgery under general anesthesia. 
 ASA Physical Status I, II, or III. 
Exclusion Criteria: 
 Age < 18 years or pregnant patients. 
 Facial images cannot be captured (e.g., due to surgical drapes, severe edema, or 
trauma). 
 Refusal or inability to provide informed consent. 
 
6. Outcome Measures 
Primary Outcome:  
1. Accuracy of Heart Rate (HR) monitoring 

Description: The success rate of non-contact HR measurement using the rPPG 
software compared to the reference values from the Masimo Root clinical 
monitoring platform. A "success" is defined as an absolute error within +/- 3 bpm. 
Time 
Frame: 
Continuous 
monitoring 
during 
the 
perioperative 
period 
(approximately 2-6 hours per patient, from anesthesia induction to recovery). 
2. Success rate of Systolic Blood Pressure (SBP) monitoring 
Description: The success rate of non-contact SBP measurement compared to the 
reference values from the Masimo Root platform. A "success" is defined as an 
absolute error within +/- 12 mmHg. 
Time 
Frame: 
Continuous 
monitoring 
during 
the 
perioperative 
period 
(approximately 2-6 hours per patient, from anesthesia induction to recovery). 
3. Success rate of Diastolic Blood Pressure (DBP) monitoring 
Description: The success rate of non-contact DBP measurement compared to the 
reference values from the Masimo Root platform. A "success" is defined as an 
absolute error within +/- 10 mmHg. 
Time 
Frame: 
Continuous 
monitoring 
during 
the 
perioperative 
period 
(approximately 2-6 hours per patient, from anesthesia induction to recovery). 
4. Success rate of Oxygen Saturation (SpO2) monitoring 
Description: The success rate of non-contact SpO2 measurement compared to 
the reference values from the Masimo Root platform. A "success" is defined as an 
absolute error within +/- 8% (when SpO2 >/= 80%) or +/- 15% (when SpO2 < 
80%). 
Time 
Frame: 
Continuous 
monitoring 
during 
the 
perioperative 
period 
(approximately 2-6 hours per patient, from anesthesia induction to recovery). 
Secondary Outcome Measures: 
5. Consistency of physiological parameters across hardware platforms. 
Description: Evaluation of the measurement consistency among three devices 
(Logitech C930, iPhone 16 Pro Max, and Samsung Galaxy S24 Ultra). 

Consistency will be assessed by calculating the Mean Absolute Error (MAE) of 
heart rate and blood pressure for each device compared to the Masimo Root 
monitor. Unit of Measure: Beats per minute (for HR) and mmHg (for BP). 
Time Frame: During the intraoperative phase (duration of the surgical procedure). 
 
7. Sample Size Justification 
The sample size of 315 participants is determined based on practical clinical 
considerations and the data requirements for validating the non-contact imaging 
algorithm. As this is an exploratory feasibility study aimed at assessing the application 
potential and parameter consistency of imaging-based monitoring in an operating room 
setting, a formal power calculation was not performed. 
A total of 315 subjects is expected to provide sufficient and diverse data across various 
perioperative clinical scenarios. This will allow for robust descriptive statistical analysis, 
signal quality evaluation, consistency testing against reference standards, and further 
algorithm optimization. 
 
8. Statistical Analysis Plan (SAP) 
Descriptive Statistics: Mean, standard deviation, and distribution for each parameter 
across surgical phases. 
Error Analysis: Calculation of Mean Absolute Error (MAE), Root Mean Square Error 
(RMSE), and Mean Error Rate (MER). 
Agreement Analysis: Linear regression analysis and Bland–Altman plots to evaluate 
correlation and systematic bias between the rPPG system and standard monitors. 
 
9. Adverse Event Management 
No adverse events are expected. Adhesive patches are non‑invasive and pose minimal 
risk. If discomfort occurs, subjects may contact the provided 24‑hour emergency number. 

Clinical evaluation will be arranged if needed. Participants may withdraw at any time 
without affecting their medical care. 
 
10. Subject Rights and Safety Protections 
Participants are protected under institutional and national human‑subject research 
policies. Informed consent will be obtained from all participants. All collected data will be 
de‑identified. Only authorized research personnel may access raw data. 
 
11. Data Management and IPD Sharing 
All data will be de-identified. De-identified datasets may be shared upon request 
beginning 6 months after study completion to protect participant privacy. 
 
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5. 
Scalise Lorenzo, Marchionni Paolo, and Ercoli Ilaria, "A non-contact optical 
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