Noncontact Respiration Rate Monitoring: An Evaluation of Four Methods

Respiratory rate (RR) is an important diagnostic indicator of deterioration in critically ill patients, therefore an accurate method for its measurement is needed. The existing methods for RR measurement are typically contact-based, ie the sensing unit is attached to the patient's body. Some young children do not tolerate contact-based methods. Contact-based methods may also cause stress, affecting RR value. The operations of four non-contact RR measurement methods were compared. These were: infrared thermal imaging; airflow sensing; vision-based chest movement tracking and respiratory airflow sensing. The study showed that all four methods could measure RR. The strengths and limitations of each method are explained.