Mathematical modelling of the human cardiovascular (CV) system represents a welcome alternative to gain insight into the response of various blood vessels, which would be otherwise very difficult to achieve in a non-invasive way. In the present work, the response of the CV system to the application of lower body negative pressure (LBNP) is studied. LBNP is used as a countermeasure to reduce the negative effects on the CV system resulting from exposure to microgravity (e.g., during space flight). Although LBNP has been subject of research for decades, its impact on the CV system remains not fully understood. The focus of the present study is to determine the hemodynamic response of the jugular vein (JV) at different values of LBNP. For the purpose of the analysis, a numerical tool was developed, i.e., a multidimensional model combining a closed-loop 0D hemodynamic model with an axisymmetric 2D model. Both the 0D and 2D models are based on real, experimentally obtained data. Such an approach enables an understanding of global hemodynamic interactions (0D model) as well as insights into local flow conditions (2D model). The coupled model was then used to determine and analyse the influence of LBNP on the JV flow conditions, which has not been demonstrated in the literature so far.
|
