Changes in levels of arachidonic acid metabolites in blood and bronchoalveolar lavage fluid after warm ischemia-reperfusion of lung.

The purpose of this study was to evaluate the role of arachidonic acid metabolites in the reimplantation response after lung transplantation in mongrel dogs. The left lung was used and two groups were studied. Group I underwent hilar stripping, while Group II underwent hilar stripping plus warm ischemia for 60 min., achieved by clamping the left pulmonary artery and veins. We measured the lung wet to dry weight ratio (W/D ratio), total pulmonary vascular resistance (TPVR), and blood and bronchoalveolar lavage fluid (BALF) levels of leukotriene B4 and C4 (LTB4,C4) and thromboxane B2 (TXB2). These parameters were measured periodically for 7 days after reperfusion. In group II, the W/D ratio and TPVR were significantly increased in comparison with Group I. The blood LTC4 level was elevated immediately after reperfusion, and BALF level of LTC4 also rose subsequently. These levels changed concomitantly with the W/D ratio. The above results suggest that arachidonic acid metabolism plays an important role in the reimplantation response, especially in pulmonary edema.