Non Invasive Continuous Blood Pressure Sensor

Study Overview
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Brief Summary
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The primary objective of this study is to collect training data in order to establish a method for correlating arterial blood pressure with voltage output signals from a non-invasive piezoelectric array sensor placed on the skin superficial to the radial artery.

Detailed Description
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The primary objective of this study is to collect training data in order to establish a method for correlating arterial blood pressure with voltage output signals from a non-invasive piezoelectric array sensor placed on the skin superficial to the radial artery. The development of this sensor could allow for non-invasive continuous measurement of arterial blood pressure. The key hypothesis is: if the piezoelectric array sensor can detect pulsatile pressure waves when placed on a near surface artery and pulse wave analysis has been shown to allow for accurate beat-to-beat estimation of blood pressure, then the device placed superficial to a near surface artery should allow for the non-invasive estimation of continuous blood pressure. Secondary objectives include identification of any significant ergonomic and motion artifact issues that could affect sensor utilization in future applications.

Official Title
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Piezoelectric Sensors for Non-invasive Continuous Arterial Blood Pressure Measurements

Conditions
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Blood Pressure, Arterial Line, Anesthesia

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults (18yr and older) Undergoing a planned (non-emergent, non-urgent) surgical procedure at DHMC for which an invasive arterial pressure monitor is standard clinical practice. Typical surgical procedures include but are not limited to craniotomy, thoracic surgery, abdominal surgery, and others. Exclusion Criteria: Morbid obesity (BMI >40) Radial artery depth > 1cm from skin at location of sensor Peripheral vascular disease Atrial fibrillation Sensitivity or allergy to silicone or medical adhesive tape Inability to consent.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Arterial Blood Pressure Measurement from Arterial Line | We will be capturing arterial blood pressure measurement per standard of care from arterial line. This will include systolic and diastolic measurements and will be sampled continuously from standard invasive monitoring equipment. Because of the high frequency sampling, we will be capturing the entire pulse waveform with each heartbeat. | Surgery start to surgery stop | 
| Arterial Blood Pressure Measurement from Non Invasive Sensor | The piezoelectric sensor array detects mechanical pressure from the radial artery that is transmitted to the skin and converts this to microvolt electric potentials. These microvolt signals are captured by the sensor array equipment. The microvolt signals will be time-synchronized with the standard of care invasive arterial line pressure data. | Surgery start to surgery stop | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Assessment of accuracy of algorithm to convert piezoelectric signal data into blood pressure measurements. | Approximately 80% of the data collected in this study will be used to refine and train an algorithm which has previously been validated on phantom and swine models to convert piezoelectric sensor data into meaningful blood pressure measurements. The remaining data (approximately 20%) will be used to test the accuracy of the algorithm against actual measured invasive blood pressure. Accuracy will be measured in terms of +/- mmHg at diastolic and systolic pressures. | Approximately 4 months following collection of data from subjects | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Piezoelectric, Array Sensor, Blood Pressure, Monitoring, Arterial Line, Non-invasive