The effect of PGE₁and temperature on lungfunction following preservation

We studied the effect of a vasodilator (prostaglandin E₁) as well as flush (F) and storage (S) temperatures (4°C or 10°C) on lung preservation in an isolated rabbit lung perfusion model. Low-potassium dextran (LPD) or Euro-Collins (E-C) solution was used as flush solution. Six groups of six animals were studied: group 1 (LPD, 4°C F-S), group 2 (LPD with PGE₁, 4°C F-S), group 3 (E-C with PGE₁, 4°C F-S), group 4 (LPD, 10°C F-S), group 5 (LPD with PGE₁, 10°C F-S), group 6 (E-C with PGE₁, 10°C F-S). After 18-hr preservation, left lungs alone were ventilated, and reperfused with fresh venous blood. PaO₂, PaCO₂, pulmonary artery pressure (PAP), tracheal pressure (P_t) during reperfusion, and wet/dry weight (W/D) ratios were measured. PaO₂ after LPD with or without PGE₁ was significantly higher than after E-C with PGE₁ at 4°C (95.8±11.5 mmHg in group 1 or 102.7±8.6 in group 2 vs. 41.8±10.5 in group 3, P<0.01) and at 10°C (119.3±2.3 in group 4 or 131.1± 6.2 in group 5 vs. 54.6±5.2 in group 6, P<0.01). PaCO₂, PAP, P_t, and W/D ratios in the LPD groups were lower than in the E-C groups. LPD/PGE₁ and LPD alone produced similar pulmonary preservation. PaO₂ of lungs flushed with LPD and preserved at 10°C was higher than that of lungs stored at 4°C. We conclude that LPD solution is superior to E-C solution in this ex vivo rabbit lung preservation model, even when PGE₁ is used. A moderate dose of PGE₁ did not improve the performance of LPD as a flush solution. Pulmonary preservation with LPD at 10°C is superior to preservation at 4°C.