Fourteen heart-lung blocks, kept in an autoperfusion system for a period of two to eight hours, were studied. Lung biopsies were performed each two hours. Ten lungs were preserved until four hours with slight degrees of alteration in the microscopic study. After the fourth hour, severe alterations developed and were represented by intra-alveolar edema, intra-alveolar haemorrhage, perivascular and peribronquial enfisema, and alveolar rupture.
lung preservation; blood