[Transmural pressure in the right atrium during positive pressure respiration in cats].

The influence of continuous positive pressure breathing (cm H2O) on the breathing mechanics, central venous pressure, and transmural pressure in the right atrium, were studied in anaesthetised cats separately during inspiration and expiration. It's shown that hemodynamics effects are directly connected with the influence of increased intrathoracic pressure during whole breathing cycles in contrast with the phase changes in natural expiration and inspiration. The inversion of relation of intrathoracic and central venous pressure due to displacement of the mechanical respiratory characteristics became the factors defining the fall of the right atrium filling pressure.