Hemodynamic and functional changes in xenogenic, perfused, isolated lungs.

Hyperacute pulmonary rejection was reproduced by perfusion of the isolated lung with heparinized heterologous blood. The cat lung was perfused with dog venous blood at a pressure of 30 mm. Hg. Pulmonary hemodynamic and functional studies showed that blood flow decreased to 14 per cent of the control and pulmonary vascular resistance increased sevenfold. Dynamic pulmonary compliance decreased only slightly to 83 per cent at 15 minutes, but normal pH, PO2, and PCO2 were maintained in the pulmonary venous blood even 15 minutes after the start of perfusion, because perfusion was decreased to a greater extent than ventilation.