PRESERVATION OF COMPETENT RABBIT LUNG-FUNCTION AFTER 30 HOURS OF STORAGE WITH A LOW-POTASSIUM DEXTRAN SOLUTION

Background: The goal of organ preservation is maintenance of physiolog ic function during extended extracorporeal storage. Methods: This stud y was designed to evaluate the efficacy of using low-potassium (4 mmol /L) dextran (1%) solution on lung function after 30 hours hypothermic (10-degrees-C) storage and to compare this with lung function after no storage. With low-potassium dextran solution rabbit lungs were flushe d (10-degrees-C, 40 ml/kg, 60 cm H2O), excised, inflated (with room ai r), and either not stored (control; no preservation; n = 9) or stored in low-potassium dextran solution (10-degrees-C) 30 hours (experimenta l group; n = 9). Results: During the flush the infusion pressure and p ulmonary vascular resistance for the two groups did not differ (17.56 +/- 1.3 versus 16.74 +/- 1.5 mm Hg/ml/sec). After either no preservati on or after 30 hours of storage, the lungs were first reperfused with low-potassium dextran solution (37-degrees-C) for 4 minutes and then w ith blood (37-degrees-C) for 30 minutes at 100 ml/min. During the repe rfusion period the mean pulmonary artery pressure and end-inspiratory airway pressure for the control and experimental groups did not differ . After reperfusion the wet and dry weights of the left lung were dete rmined. The wet/dry ratio for the two groups did not differ (5.32 +/- 2.20 versus 4.70 +/- 2.70, respectively). Conclusions: These data sugg est that cold flush, cold storage, and initial warm perfusion with low -potassium dextran solution crystalloid preserve lung function after 3 0 hours of storage.