| 摘要 |
23 448/708 TAH:cp 7/2/86 2183N Apparatus and methods are provided for determining the concentration of a gaseous component in a fluid A solid body of a natural or synthetic high polymer, which is permeable to the gaseous component, is exposed to the fluid, the polymer is exposed to infrared radiation, and the infrared absorption by the gas in the polymer is measured. In the preferred embodiment, a sensor is provided for making in vivo measurements of the concentration of CO2 in the blood. The sensor includes an optical fiber which is nonpermeable to CO2 and substantially transparent at the CO2 absorption wavelength range, and a solid body of polymeric material at the distal end of the fiber which is substantially transparent to the absorption wavelength range and permeable to CO2. An incident infrared signal is transmitted down the fiber, passes throught the body, is reflected off the distal end of the body, and the intensity of the return signal is measured by a detector. The return signal is diminished in proportion to the concentration of the CO2 in the polymeric body. The sensor is disposed within a catheter and is positionable within the narrow blood vessels of the body for continuous real time monitoring of the carbon dioxide concentration of the blood. |
