UNIVERSITY-OF-WISCONSIN SOLUTION FOR LUNG GRAFT PRESERVATION - WHICH COMPONENTS ARE IMPORTANT

Rat lung grafts were perfused with either Euro-Collins solution, Unive rsity of Wisconsin solution, or one of six modified University of Wisc onsin solutions that had been sequentially depleted of specific compon ents (n = 5 each group). After storage at 4-degrees-C for 6 hours, the isolated, ventilated pulmonary graft was reperfused for 1 hour with r ecirculating venous blood from a support animal. In a further group, l ungs were reperfused immediately after explantation to provide control values. Grafts flushed with University of Wisconsin solution function ed at control levels with regard to oxygen tension: University of Wisc onsin solution 128 +/- 2.7 mm Hg, control 126 +/- 5 mm Hg; graft blood flow: University of Wisconsin solution 9.9 +/- 0.4 ml/min, control 10 .2 +/- 0.8 ml/min; peak airway pressure: University of Wisconsin solut ion 17 +/- 0.5 mm Hg, control 16.5 +/- 0.6 mm Hg; and weight gain: Uni versity of Wisconsin solution 0.12 +/- 0.1 gm, control 0.19 +/- 0.13 g m. In contrast, lungs treated with Euro-Collins solution functioned le ss well: oxygen tension 54 +/- 6 mm Hg, graft blood flow 3.5 +/- 0.42 ml/min, peak airway pressure 35 +/- 4 mm Hg, and weight gain 4.15 +/- 0.5 gm (p < 0.0001 all parameters). Sequential removal of hydroxyethyl starch, magnesium, allopurinol, adenosine, glutathione, and lactobion ate from University of Wisconsin solution did not impair the efficacy of the solution. However, substitution of raffinose with glucose led t o significantly impaired graft function: oxygen tension 69.6 +/- 9.6 m m Hg, blood flow 6.48 +/- 0.58 ml/min, peak airway pressure 25.2 +/- 2 .8 mm Hg and weight gain 2.11 +/- 0.8 gm (p < 0.001 all parameters), c omparable with the Euro-Collins group. The major factor responsible fo r the efficacy of University of Wisconsin solution in lung graft prese rvation appears to be the impermeant trisaccharide raffinose.