Electronic Theses and Dissertations



Document Type


Degree Name

Doctor of Philosophy


Biomedical Engineering

Committee Chair

Erno Lindner

Committee Member

John J. Bissler

Committee Member

Bradford D. Pendley

Committee Member

Eugene C. Eckstein


The measurement of urinary CO2 (U-CO2) may provide timely recognition of changes in the microcirculatory status of patients, which may correlate better with the prognosis of a patient in septic shock than traditional measures like mean arterial pressure (MAP). We describe the development of a U-CO2 measurement system with a miniature planar CO2 probe that could be used to evaluate the relationship between U-CO2, the microcirculation, and patient outcome. Features of the probe like gas permeable membrane material and thickness, as well as inner hydrogel bicarbonate concentration and volume, are optimized. Parameters of the system, including sample chamber size and flow rate, are also tested. The CO2 response of the probe has been validated in standard buffer solutions with known CO2 levels. The utility of the measurement system is demonstrated through the simultaneous monitoring of U-CO2 in a model bladder using the planar CO2 probe and a commercial CO2 probe. The agreement between the measured U-CO2 values in healthy volunteer urine samples projects the possibility of using this CO2 measurement system in clinical testing to determine its utility in bedside monitoring.


Data is provided by the student.

Library Comment

Dissertation or thesis originally submitted to ProQuest.


Open access