Abstract
It is shown that microdialysis-based blood gas (pH, pCO2 and pO2) optical sensors are stable for durations of several hours in blood. This performance is uncommon with many types of membrane sensor. Microdialysis techniques can be designed to ensure that the sweep microflow samples are in biochemical equilibrium with the bulk media, even after hours of exposure to the complex composition of blood. The rate of diffusion through the membrane is not the determining factor in sensor reading, as it is with other sensor techniques that consume the analyte. The sweep fluid 95% equilibration times for microdialysis fibres were approximately double in blood compared with buffer, reflecting slower diffusion of ions. This is in contrast to the equilibration of gases through silicone hollow-fibre membranes in blood, which showed unchanged equilibration times between blood and buffer. Sensor measurements correlate well with a blood gas analyser for up to 9 h in blood, with correlation coefficients of 0.973 for the pO2 sensor 0.974 for the pCO2 sensor and 0.947 for the pH sensor. In blood, the sensors have precisions of 1.7 mmHg, 3.7 mmHg and 0.019 pH units and bias levels of -0.7 mmHg, 1.2 mmHg and 0.002 pH units, for pO2, pCO2 and pH, respectively.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Medical & Biological Engineering & Computing
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
