Device Proposal for Continuous, Non-Invasive Blood Pressure Monitoring

Abstract

Hypertension is a major risk factor for numerous conditions such as coronary artery disease and stroke causing an estimated 10.4 million deaths in 2019. Standard blood pressure (BP) measurements are obtained using a cuff that measures the blood pressure in that moment. Newer methods include the usage of 24 hour ambulatory monitors with cuffs that oscillate every 30 minutes during the day and every hour at night. These methods provide only discrete measurements that miss BP variations. A continuous monitor would detect variations as well as allow for typical daily activity resulting in a more accurate outlook at a patient's daily BP. Using a micropressure sensor, we attempted to create a continuous non-invasive BP monitor. The micropressure sensor was modified, and filled with gel. To measure the correlation between a standard BP cuff and our device, the seated participant wore the device on the wrist. After the peaks and troughs of the pressure waves were captured, the BP cuff was used immediately after. The peaks and troughs of the wave were used with the measurement from the standard cuff to attempt to predict systolic and diastolic pressure. There was a statistically significant relationship between the diastolic pressure and trough values, but the relationship between peaks and systolic pressure was not statistically significant. This correlation would be patient specific due to varying arterial stiffnesses. Next steps would include creating a simple way to calibrate the device for each patient and putting the device in the proposed wearable form.