Lung Preservation Study for Above 20 Hours of LPDG Solution in Canine Lung Allotransplantation

Park, Chang Kwon; Kwon, Kun Young; Yoo, Young Sun

Abstract

BACKGROUND: Limited ischemic tolerance of the lung has remained one of the factors that limits the expansion of pulmonary transplantation as a treatment for end-stage pulmonary disease. Numerous studies on safe long term preservation for lung transplantation has been performed for the purpose of developing ideal preservation solution with extracellular type or intracellular type solutions. In this study, we examined the efficacy of LPDG solution in lung preservation longer than 20 hours by comparison with modified Euro-Collins solution.
METHODS
Thirty-four adult mongrel dogs were divided into two groups. Donor lungs were flushed with LPDG solution(n=9) or modified Euro-Collins(MEC) solution(n=8) and stored for 24 hours at 10degrees C. All donor lungs were perfused through the pulmonary arteries with solutions containing prostaglandin E1 and verapamil. Left canine lung allotransplantations wereperformed. Assessment(hemodynamic indices and arterial blood gas analysis) of left implanted lung was made by occluding the right pulmonary artery for ten minutes using pulmonary artery Cuff. Assessment was repeated at the interval of 30 minutes, one hour, and two hours later after reperfusion and then chest X-ray, computed tomogram and lung perfusion scan were obtained. In survival dogs follow-up studies were done with assessment with chest X-ray, computed tomogram of the chest and lung perfusion scan on 7th day postoperatively. After preservation above 20 hours, pathological examinations for ultrastructural findings on right lung were performed in each group.
RESULTS
With respect to arterial oxygen tension, LPDG group was superior to MEC but there was no statistical significance for 2 hours after reperfusion. Mean pulmonary artery pressure was less increased(p<0.05) and cardiac output higher(p<0.05) than MEC group until 2 hours after reperfusion. After 2 hours of reperfusion, both groups showed transplanted lung function deteriorated gradually. Perfusion scan of the transplanted lung in LPDG group showed better perfusion rate in immediate post-reperfusion, 3 days and 7 days later respectively but there was no statistical significance and corelation with PaO2 and computed tomographic views. In scanning electron microscopy of pulmonary artery after preservation, LPDG group relatively shows less irregular protrusion of the inner surface of endothelial cell of poulmonary artery than MEC group.
CONCLUSIONS
We concluded that LPDG solution can offer safe lung preservation above 20 hours with adequate immunosuppressive therapy and prevention of the infection.