Exploring advanced applications of pulse oximetry

• Main Author: Aiw, Jia Hui
• Other Authors: Chan Chi Chiu
• Format: Final Year Project
• Language: English
• Published: 2014
• Subjects: DRNTU::Engineering::Bioengineering
• Online Access: http://hdl.handle.net/10356/60240
• Institution: Nanyang Technological University

Technological advances in electronics allow remote physiological monitoring with wireless technology and miniaturization. Conventionally, pulse oximeter takes reading at distal end such as finger, ear lobe or feet. These body parts have high mobility rate that can cause motion artifact in readings. It is propose by the author to use tragus region as a measurement site for monitoring of vital signs. The project was undertaken to assess the attachment area at tragus region in different physiological status for SpO2 and heart rate. The physiological status includes normal respiratory, voluntary hypoxemia and hyperventilation at seated position. These physiological values are analysed in Matlab by advance algorithms to extract useful information that correlated to physiological parameters of the subject. Different physiological status allows us to look into the reliability and sensitivity of sensor at the tragus region. It would involve linear regression model, statistical method such as Bland-Altman plot and histogram plot commonly used in clinical data for comparison. Our results indicate that the use of pulse oximeters on tragus to detect SpO2 is promising. The tragus readings undergo different statistics method, which produce relative positive result to replace finger as alternative reading site. Although inconsistent appeared in few subjects, it is suggested that inaccuracy may originate ii from the inadequate procedure in simulating physiological status during the experiment. A variation of (±10 bps) is observed in Bland-Altman plot that is within the normal healthy range in individuals. Averaging the instantaneous HR over a short period of time frame to smooth the irregular beat-to-beat variations that is typically used in calculating beat per minute. The variation in HR shows questionable sensitivity of sensor probe at tragus region. However, analysis on BPM reading to evaluate physiological status hints promising increased in accuracy.