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The ability to monitor blood gases, namely oxy-gen and carbon dioxide, in real-time is of critical importance to clinicians in diagnosing and treating respiratory disorders. Transcutaneous monitors measure the partial pressure of carbon dioxide diffused from the skin. These monitors are noninvasive and capable of continuously monitoring carbon dioxide. Conventional transcutaneous carbon dioxide monitors require a heating element and large calibration equipment for reliable measurements. We propose a miniaturized transcutaneous carbon dioxide monitor based on a luminescence sensing film and dual lifetime referencing technique to assess the partial pressure of carbon dioxide within the 0-75 mmHg range, covering the clinically relevant range for healthy humans, 35-45 mmHg. We measured the partial pressure of carbon dioxide with less than ~1.6% error in the given range without any post-processing and heating.
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A Miniaturized Prototype for Continuous Noninvasive Transcutaneous Oxygen Monitoring
Luminescent oxygen sensing is employed for measuring the partial pressure of oxygen diffusing through the skin, named transcutaneous oxygen. Two well-known approaches are intensity- and lifetime-based measurements for assessing transcutaneous oxygen. The lifetime-based technique is preferable as it offers lower susceptibility to optical path changes and reflections compared to the intensity-based method. High-resolution lifetime capturing is critical to accurate transcutaneous oxygen measurements from the human body. This study proposes a miniaturized prototype based on a multimodal analog front end, ADPD4101, and custom firmware. We have demonstrated that the prototype could detect small changes in the lifetime with high resolution, showing its suitability for future human subject tests. We implemented the prototype on a 68 mm × 43 mm printed circuit board (PCB) and consumes the power ×of 39 mW.
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- PAR ID:
- 10405943
- Date Published:
- Journal Name:
- 2022 IEEE Biomedical Circuits and Systems Conference (BioCAS)
- Page Range / eLocation ID:
- 486 to 490
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/BioCAS54905.2022.9948598
