[Theoretical analysis of the effect of the state of the lesser circulation on the distribution of ventilation-perfusion relationships and gas exchange in the lungs].

Using a mathematical model of functionally nonuniform lungs, the effect of gravitational inequality of ventilation-perfusion relations on gas exchange was studied. The dependence of tensions of respiratory gases in the mixed arterial blood and alveolar air upon pulmonary circulation pressure was demonstrated. The influence of changes in the tone of lung vessels on the distribution of ventilation-perfusion relations and gas exchange was investigated.