ET-KYOTO SOLUTION FOR 48-HOUR CANINE LUNG PRESERVATION

Background. ET-Kyoto (ET-K) solution, proven safe far 20-hour lung pre servation, was modified to achieve longer preservation: ET-K2 solution with more buffer capacity and ET-K3 solution with less potassium. Met hods. Lungs were preserved with one of the three solutions (with prost aglandin E(1)) at 4 degrees C for 48 hours (n = 5 for each). Left lung transplantation was performed and evaluated for 6 hours. Results. Eac h solution became acidic after preservation (p < 0.01), though the cha nge was lowest in the ET-K2 solution. All animals in the ET-K and ET-K 3 groups survived for 6 hours after reperfusion, but only 1 survived i n the ET-K2 group (p < 0.05). In all groups, partial pressure of oxyge n in arterial blood decreased gradually after reperfusion. Pulmonary v ascular resistance after reperfusion was significantly lower in the ET -K group than in the ET-K3 group (p < 0.01). Scanning electron microsc opic examination showed that endothelial cell swelling and disruption were milder in the ET-K group (with solution containing potassium of 4 4 mEq/L) than in the ET-K3 group. Conclusion. Lung preservation can be achieved for 48 hours in ET-K and ET-K3 solutions, Enhancement of buf fer capacity provides no advantage. Potassium at 44 mEq/L does not cau se deterioration of endothelial cells.