Warm ischemic injury of the lung

Canine left lower lobes which were subjected to 3 hours of warm ischemia in an atelectatic condition were compared to lobes which had not been stored. During short-term reimplantation studies, the injured lobes were characterized by marked weight gain, diminution in blood flow, increased vascular resistance, and peak airway pressure. The ventilation/perfusion ratios were high and considerable dead-space ventilation was present. Hypoxic vasoconstriction occurred in both control and stored lobes, and shunt determinations did not vary because of the low blood flows observed. Some or all of these physiological changes may serve to develop a simple screening method to evaluate techniques of pulmonary preservation.