Using Piezoelectric Sensor for Continuous （使用压电传感器连续）.pdf

Using Piezoelectric Sensor for Continuous-Contact-Free Monitoring of Heart and Respiration Rates in Real-Life Hospital Settings Tal Klap, Zvika Shinar EarlySense Ltd, Israel Abstract amongst are: low nurse-to-patient ratio, alert fatigue due to high false alarm rate and requirements to keep the In this paper we review over 1-million hours of patients independent and mobile. experience with vital signs monitoring using piezoelectric Ballistocardiogram (BCG) is the recording of micro- sensor in real clinical settings. The sensor developed by body movements associated with the ejection of blood EarlySense ltd is placed under the mattress and has no bolus in each heart pulse (cardioballistic effect). direct contact with the patient. The force exerted on the During the 50’s and 60’s, heart functionality analysis sensor is a summation of 3 sources, originating from based of BCG was an active topic for research among gross body movement, chest wall movement due to cardiologists, however, research activity faded in the respiration, and recoil of the body due to heart pulse years to come due to practicality issues and the (cardioballistic effect). advancements in ECG analysis. The piezoelectric transducer generates a signal that can be separated into motion, respiration and