Assessment of inspiration and expiration time using infrared thermal imaging modality

Abstract

Breathing is one of the important vital signs assessed by healthcare practitioner for patient monitoring and disease management. There are several methods used to evaluate breathing activities such as respiratory inductive plethysmography, impedance pneumography, bioacoustics method, spirometry and manual assessment. Most of these devices require external attachment on patient such as belt, electrodes and sensor which could be inconvenient if used over a long period of time. Infrared Thermal Imaging (ITI) is a contactless device that detects temperature changes which can be used to assess breathing since hot air particles are being released to surrounding through nose which create temperature variance during breathing. Majority of studies conducted on breathing function were focused on respiratory rate. Therefore, this study assessed the timing of inspiration (TI) and expiration (TE) in three different breathing patterns which are normal, prolonged expiration and rapid breathing by using Infrared Thermal Imaging (ITI). A total of thirty-three subjects were required to simulate various breathing patterns by using a video-guided method. The assessment of TI and TE was recorded using ITI and Respiratory Inductive Plethysmograph (RIP) simultaneously. Results obtained from the ITI images show consistent deflections on the plotted graph which reflect the transition point of inspiration and expiration. This transition point allowed us to measure the TI and TE between ITI and RIP. Our analysis shows that there are no significant differences of the reading obtained between ITI and RIP in TI and TE. Correlation analysis also shows that there was positive correlation between measurement obtained by ITI and RIP. These findings suggest that ITI technique could be used as an alternative method to assess breathing dynamics.