Tolerance of the isolated perfused lung to hyperthermia

With the use of in vivo isolated lung perfusion for targeting antitumor therapy in the treatment of lung cancer, tolerance of normal lung tissue to the tumoricidal conditions becomes the limiting factor. This study was performed to determine the short-term tolerance of the lung to hyperthermia. Isolated dog lung lobes were perfused with autologous blood or an artificial salt solution at constant flow. Measurements of lung weight, extravascular water, vascular volume, serotonin uptake, urea permeability surface area product, perfusion pressure, and lung compliance were made with the temperature at about 37 degrees C. The temperature was then set at between 37 degrees and 45 degrees C, and at the end of the subsequent 2 hours the measurements were repeated. When the temperature was less than about 44.4 degrees C, hyperthermia had no detectable influence on the measured variables. Thus on the time frame consistent with in vivo perfusion therapy the normal lung appears to tolerate a fairly severe hyperthermia.