The Effect of Different Parameters (Temperature, O2 Consumption, Blood Flow, Hemoglobin Content) on the tcPo2 Calibration Curves Calculated by the Capillary Loop Model
The exchange processes of blood gases within and through the upper skin had become of considerable interest in the last years since the transcutaneous blood gas monitoring had been introduced in clinics (see Huch et al., 1981). Since the relationship between transcutaneous Po2 measured at 43°C at the skin surface and arterial Po2 at body temperature (37°C) is very complex, we developed a model of the upper skin, the capillary loop model, which allows to simulate gas exchange processes (Grossmann et al., 1981; Grossmann and Lübbers, 1981; Grossmann, 1982). Using this model, the influence of physiological parameters (as skin blood flow, hemoglobin content of blood, tissue oxygen consumption, diffusional properties and temperature) as well as the influence of structural parameters (capillary loop length and diameter, thickness of the different layers) on the Po2 distribution was investigated (Lübbers, 1979; 1981). In the same way, temperature and Pco2 fields were calculated. Since for practical applications the actual calibration curve of the tcPo2 vs. the Pao2 is of main importance, we used our model to calculate such calibration curves and to investigate in which way they are influenced by the different physiological parameters.
KeywordsHemoglobin Concentration Skin Blood Flow Diffusional Property Hemoglobin Content Identity Line
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