FAST OPTOCHEMICAL SENSOR FOR CONTINUOUS MONITORING OF OXYGEN IN BREATH-GAS ANALYSIS

An application of an optochemical oxygen sensor to respiratory gas mon itoring is presented. A new prototype module has been developed, which is suitable for the determination of oxygen concentration in mainstre am breath-gas flow, directly at the patient's mouth. The sensor is bas ed on the measurement of the quenching of the intensity of photolumine scence of the dye platinum(II)-octaethylporphyrin-ketone by molecular oxygen. The dye has been immobilized in various polymers with and with out plasticizer. The characteristics of the resulting oxygen sensitive membranes have been determined with emphasis mainly on their oxygen r esponse characteristics, such as calibration graphs, oxygen sensitivit ies, oxygen resolution and response times. The suitability of the opto chemical oxygen sensors for clinical use in respiratory gas-exchange m easurements has been demonstrated in combination with a prototype inst rument.