Hypothermia inhibits the alveolar epithelial injury caused by hyposmotic albumin solution during preservation of the resected human lung

Abstract

This study was conducted to determine whether hypothermia inhibited alveolar epithelial injury in the resected human lung during preservation. Hyposmotic albumin solution, 248 mOsm/kg, was instilled into the alveolar spaces of resected human lungs which were inflated with an airway pressure of 7 cmH2O and stored at either 37 degrees C or 8 degrees C for 4 h. Alveolar fluid was aspirated and the influx of lactate dehydrogenase (LDH) and globulin into the alveolar spaces, as markers of alveolar epithelial injury, was measured. Ion transport and fluid clearance across the alveolar epithelium were calculated by the changes in electrolyte and albumin concentrations in the alveolar fluid, respectively. While the LDH levels and globulin concentrations increased significantly in the hyposmotic experiments at 37 degrees C, hypothermia inhibited these increases. Alveolar fluid clearance at 37 degrees C increased to 20% in the hyposmotic experiments compared with 12% in the control isosmotic experiments; however, sodium and chloride transport in the hyposmotic experiments was not significantly different from that in the isosmotic experiments. Thus, we conclude that hypothermia at 8 degrees C inhibits alveolar epithelial injury caused by the hyposmotic solution in resected human lungs. Moreover, alveolar ion and fluid clearance mechanisms were preserved across the injured alveolar epithelial cells.