The effect of potassium ion in flushing solution on a part of donor lung preservation characteristics

We investigated the effect and mechanism of action of potassium in flushing solution on lung graft function. Five groups of rabbits with different potassium concentration solutions were evaluated : Group 1 (n = 7), 0mEq/L ; Group 2 (n= 6), 5mEq/L ; Group 3 (n= 6), 10mEq/L ; Group 4 (n=6), 15mEq/L and Group 5 (n=10), 20mEq/L. The grafts were topically flushed in vivo with the respective solutions and harvested. After 18 hours preservation at 8°C, graft function assessment was performed. We used the system in our department which utilizes autologous blood. The graft was placed in a closed circuit for 30minutes. We defined this period as the first reperfusion. The circuit was then intercepted, and the grafts were perfused with preserved autologous blood for 120 seconds. We defined this period as the second reperfusion. During flushing, the mean pulmonary artery pressure (PAP) was significantly higher (p < 0.05-0.01) in Group 5 than in the other groups. During the 1st reperfusion, 2 cases in Group 2 were excluded due to extreme values on Smirnov test. Two cases in Group 4 and 4 cases in Group 5 were excluded due to lung edema. During the 1st reperfusion, a significant indirect correlation was found between average PAP (avPAP) in each group (Y) and potassium concentration (X) (Y = 24.2 +0.85X ; r = 0.912, p