Abstract: A test cartridge for evaluating biological fluids can have a sensor flow cell defining a flow path for selectively passing a test fluid or biological fluid across a sensor to evaluate the sensor or the biological fluid. The test cartridge can include a sample port and at least one deformable reservoir, both formed as part of the test cartridge and fluidly connected to the flow path upstream of the sensor. A biological fluid can be manually fed into the flow path through the sample port for evaluation by the sensor. Before the biological fluid is fed through the sample port, the deformable reservoir can be manually ruptured to pass the test fluid contained within the reservoir across the sensor to first evaluate the sensor. In an example, the deformable reservoir can include a first reservoir containing a liquid quality control (LQC) fluid and a second reservoir containing a calibration fluid.

Abstract: A gaseous nitric oxide (NO) sensor having a working electrode configured such to induce NO molecules proximate the working electrode to undergo an electrochemical oxidation reaction. The electrochemical oxidation reaction transfers electrons from the NO molecules to the working electrode, creating a measurable current corresponding to the NO concentration within the fluid sample. An external membrane can be deposited onto the working electrode to separate the fluid sample from the working electrode. The external membrane can comprise an ionomer selectively permitting diffusion of NO molecules through the external membrane from the fluid sample to the working electrode. In an example, the fluid sample can be heated to a predetermined temperature to facilitate dissociation of NO from its hemoglobin bonded forms proximate the external membrane.

Abstract: A test cartridge for evaluating biological fluids can have a sensor flow cell defining a flow path for selectively passing a test fluid or biological fluid across a sensor to evaluate the sensor or the biological fluid. The test cartridge can include a sample port and at least one deformable reservoir, both formed as part of the test cartridge and fluidly connected to the flow path upstream of the sensor. A biological fluid can be manually fed into the flow path through the sample port for evaluation by the sensor. Before the biological fluid is fed through the sample port, the deformable reservoir can be manually ruptured to pass the test fluid contained within the reservoir across the sensor to first evaluate the sensor. In an example, the deformable reservoir can include a first reservoir containing a liquid quality control (LQC) fluid and a second reservoir containing a calibration fluid.

Abstract: A dual lumen CO.sub.2 catheter is formed of medical grade dual lumen silicone rubber tubing which has been impregnated with tridodecyl amine. The silicone tubing is gas permeable, and an external reference electrode is used to monitor the potential across the impregnated outer wall of the dual lumen tubing as a function of pH. The analyte to be monitored is selected from the group consisting of CO.sub.2, NH.sub.3, SO.sub.2, NO.sub.2, H.sub.2 S, and HCN, the internal reference and electrolyte solutions contained in the lumens being selected in response to the particular analyte desired to be monitored. In a CO.sub.2 embodiment, the reference lumen is filled with a buffered internal reference solution, and the response lumen is filled with a bicarbonate filling solution. Reference wires formed of Ag/AgCl in respective ones of the lumens forms the internal electrodes.