Carbon Dioxide Quantification in Human Breath Using Infrared Thermography

• Vitor Furtado Paes UFMG
• Jucélia Nascimento Rosa UFMG
• Matheus Pereira Porto UFMG

DOI: https://doi.org/10.5753/sbcas_estendido.2026.25343

Resumo

Carbon dioxide concentration in exhaled breath is a clinical metric for assessing respiratory and metabolic function. However, traditional capnography systems require physical contact, which can cause patient discomfort. This paper presents an exploratory investigation into the use of quantitative optical gas imaging as a non-invasive, remote sensing alternative for dynamically estimating CO₂ in human breath. A pilot study was conducted using a cooled mid-wave infrared thermographic camera and a narrow-bandpass filter. The results revealed peak CO₂ concentrations of approximately 50,000 ppm (5%) during nasal exhalation, consistent with standard physiological end-expiratory baseline ranges.

Referências

CK, S. S. (2025). To assess the effect of planned teaching programme on knowledge regarding the end-tidal carbon dioxide monitoring among the student nurses from a selected college in mumbai. A and V Pub International Journal of Nursing and Medical Research, 4(1):20–24.

Dervieux, E., Théron, M., and Uhring, W. (2022). Carbon Dioxide Sensing—Biomedical Applications to Human Subjects. Sensors, 22(1).

Gerlach, G., Guth, U., and Oelßner, W. (2019). Carbon dioxide sensing: fundamentals, principles, and applications. John Wiley & Sons.

Ghorbani, R. and Schmidt, F. M. (2017). Real-time breath gas analysis of CO and CO2 using an EC-QCL. Applied Physics B, 123.

Gordon, I. E., Rothman, L. S., Hargreaves, e. R., Hashemi, R., Karlovets, E. V., Skinner, F., Conway, E. K., Hill, C., Kochanov, R. V., Tan, Y., et al. (2022). The HITRAN2020 molecular spectroscopic database. Journal of quantitative spectroscopy and radiative transfer, 277:107949.

Kang, R., Liatsis, P., and Kyritsis, D. (2022). Emission quantification via passive infrared optical gas imaging: A review. Energies.

Lou, C., Jing, C., Wang, X., Chen, Y., Zhang, J., Hou, K., Yao, J., and Liu, X. (2019). Near-infrared tunable diode laser absorption spectroscopy-based determination of carbon dioxide in human exhaled breath. Biomedical optics express, 10 11:5486–5496.

Paes, V. F., Rosa, J. N., Costa, P. B., Ferreira, R. A. M., and Porto, M. P. (2025). Calibration of a cooled MWIR camera with a narrow-band filter for quantitative thermography. Quantitative InfraRed Thermography Journal, 0(0):1–20.

Schmalisch, G. (2016). Current methodological and technical limitations of time and volumetric capnography in newborns. BioMedical Engineering OnLine, 15.