Contactless monitoring of heart and respiratory rate in anesthetized pigs using infrared thermography

Autoři: Carina Barbosa Pereira aff001;  Henriette Dohmeier aff001;  Janosch Kunczik aff001;  Nadine Hochhausen aff001;  René Tolba aff002;  Michael Czaplik aff001
Působiště autorů: Department of Anesthesiology, Faculty of Medicine, RWTH Aachen University, Aachen, NRW, Germany aff001;  Institute for Laboratory Animal Science and Experimental Surgery, Faculty of Medicine, RWTH Aachen University, Aachen, NRW, Germany aff002
Vyšlo v časopise: PLoS ONE 14(11)
Kategorie: Research Article
doi: 10.1371/journal.pone.0224747


Pig experiments have played an important role in medical breakthroughs during the last century. In fact, pigs are one of the major animal species used in translational research, surgical models and procedural training due to their anatomical and physiological similarities to humans. To ensure high bioethical standards in animal trials, new directives have been implemented, among others, to refine the procedures and minimize animals’ stress and pain. This paper presents a contactless motion-based approach for monitoring cardiorespiratory signals (heart rate and respiratory rate) in anesthetized pigs using infrared thermography. Heart rate monitoring is estimated by measuring the vibrations (precordial motion) of the chest caused by the heartbeat. Respiratory rate, in turn, is computed by measuring the mechanical chest movements that accompany the respiratory cycle. To test the feasibility of this approach, thermal videos of 17 anesthetized pigs were acquired and analyzed. A high agreement between infrared thermography and a gold standard (electrocardiography and capnography-derived respiratory rate) was achieved. The mean absolute error averaged 3.43 ± 3.05 bpm and 0.27 ± 0.48 breaths/min for heart rate and respiratory rate, respectively. In sum, infrared thermography is capable of assessing cardiorespiratory signals in pigs. Future work should be conducted to evaluate infared thermography capability of capturing information for long term monitoring of research animals in a diverse set of facilities.

Klíčová slova:

Algorithms – Animal welfare – Cameras – Electrocardiography – Heart rate – principal component analysis – Swine – Vibration


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2019 Číslo 11