Towards a Temperature Compensated Model for a Blood-pH Sensor in Extracorporeal Circulation

Blood-pH Optical Measurement: A Model to Compensate for the Effects of Temperature

“…In addition, it proved to be robust against changes in hematocrit and blood flow [23]. In this article, we investigated and compensated for the measurement error due to the variation of the quantum efficiency of the fluorophore induced by potential variation of the blood temperature, thus extending the analysis and results previously presented at I2MTC 2022 [2].…”

“…Thus, a custom NTC sensor was positioned in-line within the tubing system using a Y-connector. The temperature (T) was acquired, using an Arduino microcontroller and a Labview VI, simultaneously with R, placing the in-line temperature probe as close as possible (less than 20 cm) to the pH sensor to obtain an estimate of blood temperature [2].…”

“…This is a buffer solution commonly used in biomedical research having osmolarity and ion concentrations matching those of human blood, but presenting costs and test complexity significantly lower than those of blood. Such tests revealed that a PBS temperature variation of just a few Celsius degrees causes an error no longer complying with the maximum permissible measurement error [2]. In light of these results, in this article, a more detailed and deepened analysis is carried out by implementing an ECC setup using bovine blood.…”

“…Under physiological conditions, the human body keeps blood-pH within a very narrow range: [7.36, 7.44] pH. Deviations from this range generally reveal an altered physiological state, and a few tenths out of it might have harmful consequences on the circulatory, respiratory, and cerebral systems, up to the death of the patient [2]- [4]. For these reasons, major health organizations include blood-pH among the most important parameters to keep continuously monitored during ECC treatments [5]- [7].…”

“…In the proceedings paper [2], a preliminary analysis of the effects of the measurand temperature was performed using PBS. This is a buffer solution commonly used in biomedical research having osmolarity and ion concentrations matching those of human blood, but presenting costs and test complexity significantly lower than those of blood.…”