Theoretical models of changes in haemodynamic parameters and gas exchange in univentricular circulation

Aim. To develop theoretical models of changes in haemodynamic parameters of patients with univentricular haemodynamics. Methods. We analysed the effects of redistributing blood flow between the two circulatory systems (pulmonary and systemic) on systemic oxygen delivery and examined changes in the arterial and venous blood gas compositions. Mathematical analyses on the basis of oxygen flow into the pulmonary circulatory system and its consumption during circulation were performed according to Fick principle for cardiac output. Calculations were performed using equations describing changes in the delivery and consumption of oxygen during univentricular circulation. Furthermore, computer simulations were employed to investigate changes in haemodynamic parameters and gas exchange associated with pathological processes such as pulmonary venous hypoxemia, reduction in systemic flow rate and mixed venous blood desaturation. Calculations were performed under conditions with oxygen concentration of >0% or