Feasibility to Measure Tissue Oxygen Saturation Using Textile-Integrated Polymer Optical Fibers

Area of Science:

• Biomedical Engineering
• Textile Science
• Medical Devices

Background:

• Tissue oxygen saturation (StO2) is critical in pressure injury (PI) development, as hypoxia leads to tissue necrotization.
• Pressure-induced occlusion of blood circulation reduces StO2, causing hypoxia and subsequent PI, which are painful, slow to heal, and costly.
• Early detection of hypoxia via near-infrared spectroscopy (NIRS) is essential for PI prevention.

Purpose of the Study:

• To investigate the feasibility of a wearable NIRS device for long-term monitoring of StO2.
• To develop a NIRS device integrated into textiles, ensuring it is comfortable and does not exert pressure.
• To assess the efficacy of textile-based optical fibers for NIRS measurements.

Main Methods:

• Investigated textile light emitters (LEs) and detectors (LDs) using knots and loops on a phantom.
• Quantified light coupling efficiency of LEs and LDs based on loop configurations and fiber counts.
• Validated the textile NIRS device through phantom inclusions mimicking hypoxia and in-vivo arm occlusion tests.

Main Results:

• Textile knots and loops demonstrated comparable light coupling efficiency, with optimal performance at 3 loops per fiber.
• Increased loops per fiber enhanced efficiency for both LEs and LDs.
• The textile NIRS system successfully identified hypoxic inclusions in phantoms and showed expected StO2 decreases during in-vivo arm occlusion.

Conclusions:

• Optical fibers integrated into textiles are feasible for creating wearable NIRS devices.
• This technology holds promise for continuous, non-invasive StO2 monitoring to prevent pressure injuries.
• Textile-based NIRS offers a comfortable and effective solution for hypoxia detection in PI prevention strategies.