[Microcirculation in the pulmonary vessels during artificial ventilation of different frequencies and volumes].

In acute experiments on cats with closed chest by means of biomicroscopic method it has been shown that artificial ventilation of increased frequency or volume causes the decrease of diameters of arterioles, venules, wide capillaries and also the decrease of the length of functional narrow capillaries. The constriction degree of arterioles and venules depends on their initial diameter. The length of the functional narrow capillaries is being changed to the great extent under frequency increase. Decrease of the volume of the artificial ventilation causes differently directed changes of these parameters in various regions of the lungs. It is supposed that other neuro-humoral factors take part in the realization of the determined changes except alveolar pressure.