NEUTROPHIL LEUKOTRIENE GENERATION AND PULMONARY DYSFUNCTION AFTER ABDOMINAL AORTIC-ANEURYSM REPAIR

Background. The purpose of this study was to assess the role of polymo rphonuclear neutrophil (PMN)-generated leukotriene B-4 (LTB(4)) as an etiologic agent in the pulmonary dysfunction seen after operation in p atients undergoing abdominal aortic aneurysm repair. Methods. Blood wa s analyzed in 10 consecutive patients undergoing elective infrarenal a bdominal aortic aneurysm repair for plasma thromboxane B-2, lactoferri n, C3a, and PMN-generated LTB(4). Results. There was a close linear co rrelation (r = 0.88; p < 0.001) between aortic clamp time and PMN LTB( 4) production. Conversely, aortic clamp time and the ratio of arterial oxygen pressure to fraction of inspired oxygen, a measure of pulmonar y function, were inversely related (r = -0.80; p < 0.008). PMNs from p atients with long aortic cross-clamp times generated three times more LTB(4) than those patients with short cross-clamp times (194 +/- 29.6 vs 64.9 +/- 9.7 ng per 5 x 10(6) PMN; p < 0.05). Similarly, the pressu re/inspired oxygen ratio was significantly lower on admission to the i ntensive care unit in patients with long cross-clamp times as compared with patients with short cross-clamp times (237 +/- 14 vs 342 +/- 5; p < 0.005). In addition, patients with long cross-clamp times remained intubated longer than patients with short times (1.6 +/- 0.2 vs 0.6 /- 0.4 days; p < 0.04). Conclusions. These data suggest a causal role for LTB(4) in the generation of pulmonary dysfunction in patients unde rgoing abdominal aortic aneurysm repair, similar to what has been show n in animal models.