[Assessment of fluid balance and several hemodynamic parameters in lung surgery using the method of impedance plethysmography].

The hemodynamic effects of different modes of controlled ventilation (CV) were studied by means of impedance plethysmography in 52 anesthetized patients during surgery on the lungs, trachea, and bronchi. To adapt this investigation technique to the conditions of the operating room, a specially designed device was applied for extracorporeal measurement of electric resistance of the blood flow. It was found that impaired transcapillary exchange of fluid in the lungs and its accumulation in the interstitial spaces were secondary to the operated lung collapse irrespective of the composition of the inhaled gas mixture used for the controlled ventilation of the contralateral lung. A differential approach to the ventilation of the dependent and independent lungs using the conventional and high-frequency CV modifications allows for an optimal compensation for the damaged transcapillary exchange of fluids in the lungs, is most physiological, sparing, and organ-saving.