High concentrations of oxygen are routinely administered to patients undergoing routine surgical procedures even though it is highly likely, at least in patients with normal lung function, that this is unnecessary and in fact may be doing unnecessary harm. Therefore, we plan to assess whether there is any evidence of lung injury during surgery resulted from administration of high concentrations of oxygen by measuring Isofurans (IsoFs) in exhaled breath condensate. In our studies in mice that were exposed to high concentrations of oxygen we also found that circulating levels of thrombomodulin were increased. Thrombomodulin is present in endothelial cells and upon injury they release thrombomodulin into the circulation. Endothelial cell injury is known to occur in hyperoxic-induced lung injury. Therefore, in addition to measuring IsoFs in exhaled breath condensate we will also measure plasma concentrations of thrombomodulin as an indicator of endothelial injury.
