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Authors
Gøtzsche, Mette; Nielsen, Stinne Klitgaard; Rees, Stephen Edward

Identifier
10.3182/20090812-3-DK-2006.00043

Index Terms
Circulatory and respiratory systems

Abstract
Control of respiration has previously been investigated, and models have been built to explain dierent aspects of respiration. Models of respiratory drive have been limited in terms of the description of acid-base relations in blood. The purpose of this study is to explore the consequences of adding an acid-base model of the whole body to a respiratory drive model. We built a model that combines a compartment model of acid-base relations of the whole body, and a model of respiratory drive. We explored which effect the buffering capacity of full blood compared to only plasma has on respiratory drive, and we investigated which consequences the addition of body compartments has on the dynamic behavior of the model. The addition of a whole blood model results in only small differences in respiratory drive over the physiological range. Adding compartment volumes for blood, tissue and interstitial fuid results in a changed dynamic behavior when the system is exposed to a typical physiological change. In conclusion, it is not necessary to include the buffering capacity of whole blood compared to plasma in a model of this kind. A compartment model seems to give a better understanding of the dynamics of change in respiration.

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