Mathematical modelling of microvascular oxygen transport and the impact of blood pressure

Abstract: Cardiovascular diseases are the most common cause of death worldwide. There are known risk factorsfor cardiovascular diseases, such as high blood pressure, and it is also known that cardiovasculardiseases are associated with both the macrocirculation and the microcirculation. The macrocirculationis the term for the large vessels within the circulatory system, while microcirculation refersto the small vessels near the cells. In the clinics, the macrocirculation is more commonly examinedthan the microcirculation. Hypothetically indications of cardiovascular diseases could be foundearlier in the microcirculation than in the macrocirculation. If that is true, cardiovascular diseasescould be found earlier than as of today by microcirculatory examinations. The microcirculation hasbeen studied previous with mathematical models. However, there is no mathematical model on theoxygen transport in the skin microcirculation that constitute ordinary differential equations, has ahigh time resolution and where the impacts on the oxygen transport of risk factors of cardiovasculardiseases are studied.This thesis showcases that the microvascular oxygen transport is possible to study in high resolutionwith a mathematical model and that high blood pressure may have an impact on the abilityto recruit more vessels due to a perturbation of the blood system. The model shows the main principlesof the dynamics of the oxygen in skin microcirculation. Although the model is a simplificationof the real microcirculatory system, the model is able to describe experimental data. Further knowledgeabout the microcirculation and the impact of blood pressure has been drawn from the model.An improved model could be used to understand and learn even more about the microcirculationand the impact of more risk factors besides high blood pressure. That knowledge is important tofind and treat cardiovascular diseases earlier than as of today to worldwide decrease the morbidityand mortality of cardiovascular diseases.