In response: Blood CO2 exchange monitoring, Haldane effect and other calculations in sepsis and critical illness
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We want to thank Drs. Chiarla and Giovannini for their interest and their insightful comments on our study [1, 2]. We absolutely agree with the conclusion that PcvaCO2/CavO2 reflects not only the ongoing anaerobic CO2 production, but also the buffer power of blood , and we congratulate Chiarla and Giovannini for their concise physiological elucidation. We also believe that the combination of these effects is highly responsible for the enhanced prognostic significance of this variable.
In addition to their contribution to a deeper understanding of the magnifying effect of pH on PcvaCO2/CavO2 prognostic value, the Authors emphasize their special interest in several cases where CcvaCO2/CavO2 exceeded PcvaCO2/CavO2. As the authors already comment, over the physiological range of CO2 contents, where the relationship between CO2content and pressure remains quasi linear, the difference should be close to zero, but some variability could derive from the amplification of slight measurement...
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Conflict of interest
The authors declare that they have no competing interests.
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