"AI-Based Noninvasive Blood Pressure Monitoring Compared to Invasive Arterial Measurement"

NCT06915376 | Completed

• 1 other identifier: TABED-1-25-1137
• Study Type: observational
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this clinical trial is to evaluate a new, noninvasive method for continuously measuring blood pressure during surgery. This method combines two common types of signals - pulse oximetry and electrocardiography (ECG) - and uses artificial intelligence (AI) to help improve accuracy. Researchers will compare this method to the standard invasive arterial blood pressure (IABP) monitoring to see if it can safely and effectively replace invasive measurements in certain situations. In surgeries, keeping blood pressure stable is extremely important. Sudden drops (hypotension) or spikes (hypertension) in blood pressure can cause serious organ problems after surgery. That's why continuous blood pressure monitoring is necessary, especially during key moments like anesthesia induction, intubation, and surgical positioning. In high-risk patients, clinicians often use invasive monitoring by inserting a catheter into an artery. While accurate, this method can cause complications, including bleeding, infection, blood clots, and in rare cases, damage to the limb. Studies show that blood clots can occur in nearly 20% of radial arterial lines, and up to 15% of cases experience bleeding or hematoma. Even life-threatening problems such as limb ischemia and embolism still occur in about 1% of patients. Because of these risks, noninvasive continuous blood pressure measurement (NCBPM) devices are needed. Pulse oximeters, which are already used in all surgeries, measure oxygen in the blood and produce a waveform called photoplethysmography (PPG). This waveform changes with each heartbeat and reflects blood volume and flow. It can provide useful cardiovascular information, and in recent years, researchers have explored using PPG to estimate blood pressure. However, PPG alone may not give accurate results in all patients or conditions. One reason for this is that important heart-related signals - like the time between heartbeats (R-R interval), the heart's pumping strength, and electrical conduction - are not captured by PPG alone. These signals are available through ECG. By combining ECG with PPG, researchers hope to get a more complete understanding of each heartbeat, and use this to estimate blood pressure more accurately. In this study, the new combined method is called CPES (combined pulse oximeter and ECG signals). It uses signals from both devices, analyzed by artificial intelligence, to generate continuous blood pressure readings. The study will compare these readings with direct invasive arterial blood pressure values. The main question the study aims to answer is: Can CPES accurately measure systolic and diastolic blood pressure within 5 mmHg of the invasive method? This threshold is based on international standards (AAMI) for acceptable accuracy in blood pressure monitoring during surgery. Secondary questions include: Can CPES track rapid blood pressure changes during critical moments, such as after anesthesia drugs are given, during laryngoscopy, intubation, and surgical maintenance? Does the accuracy of KPES stay the same when the surgical table is tilted 15 degrees up (reverse Trendelenburg) or down (Trendelenburg)? These positions are commonly used in surgery and may affect blood pressure measurements. Participants in this study will be adult patients undergoing general anesthesia. All participants will: Have standard invasive arterial monitoring during surgery Wear ECG electrodes and a pulse oximeter Be monitored in real time using both standard and experimental systems Be placed in different surgical positions (as tolerated) for short periods to evaluate effects on blood pressure measurement Data will be collected at various stages of surgery and in different positions. The study does not change routine care but adds additional, noninvasive sensors for research purposes. This study may help develop safer and more comfortable ways to measure blood pressure continuously during surgery. If successful, this method could reduce the need for invasive lines in many patients, lowering the risk of complications and making surgery monitoring easier and more cost-effective. It may also be useful in settings where invasive monitoring is not possible, such as emergency departments or outpatient procedures.

Conditions

Blood Pressure Measurement

Keywords

Noninvasive Blood Pressure Monitoring; Photoplethysmography; Artificial Intelligence; Intraoperative Hemodynamics

Outcome Measures

Primary Outcomes (2)

• Primary Outcome-1: Accuracy of Noninvasive Systolic Blood Pressure Estimation Compared to Invasive Reference

  The predicted systolic blood pressure values obtained from the combined pulse oximeter and ECG signal (CPES) system will be compared to invasive arterial blood pressure (IABP) measurements. Accuracy will be evaluated using the following statistical metrics: Mean Squared Error (MSE) Mean Absolute Error (MAE) Correlation Coefficient (R) Coefficient of Determination (R²)

  Intraoperative period (from induction to surgical maintenance)

• 2. Primary Outcome-2: Accuracy of Noninvasive Diastolic Blood Pressure Estimation Compared to Invasive Reference

  The predicted diastolic blood pressure values obtained from the CPES system will be compared to invasive arterial blood pressure (IABP) measurements. Accuracy will be assessed using: Mean Squared Error (MSE) Mean Absolute Error (MAE) Correlation Coefficient (R) Coefficient of Determination (R²)

  Intraoperative period

Secondary Outcomes (2)

• Secondary Outcome-1: Detection of Rapid Hemodynamic Changes During Critical Intraoperative Events

  From anesthesia induction to 10 minutes after intubation

• Secondary Outcome-2: Effect of Patient Position on Noninvasive Blood Pressure Estimation Accuracy

  During intraoperative positional changes (Trendelenburg and reverse Trendelenburg)

Study Arms (1)

Single Observational Cohort

This study includes a single group of adult patients undergoing elective non-cardiac surgery under general anesthesia. All participants will receive standard invasive arterial blood pressure monitoring. Simultaneously, noninvasive blood pressure data will be collected using the CPES (Combined Pulse Oximeter and ECG Signals) system. The study aims to compare the accuracy of CPES measurements to invasive values within the same individuals. No randomization or assignment to separate intervention groups will occur.

Device: CPES Monitoring

Interventions

CPES Monitoring DEVICE

Noninvasive blood pressure data will be collected using a combined pulse oximeter and ECG signal system (CPES) during elective non-cardiac surgery under general anesthesia. This system is used for observational purposes and does not alter the standard of care. The goal is to compare CPES-derived blood pressure values with invasive arterial blood pressure measurements.

Single Observational Cohort

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Study participants will be recruited from adult patients undergoing elective non-cardiac surgery under general anesthesia at Konya City Hospital. All participants will have a clinical indication for arterial catheter placement as part of routine intraoperative monitoring.

You may qualify if:

• Clinical indication for arterial catheter placement
• Age ≥18 years
• American Society of Anesthesiologists (ASA) physical status classification ≤3
• Planned surgical duration \>60 minutes
• Non-cardiac surgery
• Expected supine positioning during the procedure
• Initial postoperative recovery planned in the Post-Anesthesia Care Unit (PACU)

You may not qualify if:

• Refusal to give informed consent
• Severe peripheral vascular disease
• Surgeries involving manipulation of major arteries
• Positive Allen's test
• Inability to place an arterial catheter in the upper extremity
• Presence of an arteriovenous fistula for hemodialysis
• Inability to measure NIBP (noninvasive blood pressure) on the same arm as the arterial catheter
• Difference greater than 10 mmHg in SBP or DBP between the two arms based on NIBP measurements
• Abnormal arterial pressure waveforms detected in history or initial IABP monitoring (e.g., pulsus paradoxus, pulsus alternans, pulsus bisferiens, pulsus parvus et tardus)
• Atrial fibrillation
• Body Mass Index (BMI) \>35 kg/m²
• Preoperative hemoglobin level \<10 g/dL or \>16 g/dL
• Esophageal or nasopharyngeal pathology, or aortic coarctation
• Conditions affecting accurate pulse oximeter readings, such as nail or finger disorders (e.g., nail fungus or scleroderma), or presence of nail polish, dye, henna, or tattoos on fingers or nails.

Sponsors & Collaborators

• Nevsehir Public Hospital: lead

Study Sites (1)

Konya City Hospital

Konya, Konya/Meram, 42040, Turkey (Türkiye)

Location

Study Officials

• Mehmet Akif Yazar, MD

  Konya City Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Target Duration: 1 Day
• Sponsor Type: OTHER GOV
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: March 28, 2025
• First Posted: April 8, 2025
• Study Start: April 7, 2025
• Primary Completion: November 1, 2025
• Study Completion: November 20, 2025
• Last Updated: November 21, 2025

Record last verified: 2025-11

Locations

TU (1)