RESUMO
OBJECTIVE: The role of aprotinin in the prevention of lung reperfusion injury was investigated in the patients undergoing cardio-pulmonary bypass (CPB) for coronary artery bypass grafting (CABG) operations. METHODS: The study was planned randomly and prospectively. Two hundred milliliters of physiological saline solution was added to the prime solution of patients in group I (n=10) whereas, 200 ml aprotinin (Trasylol, Bayer AG) was given to patients in group II (n=10). In order to measure lung tissue malondialdehyde (MDA) levels, glutathion peroxidase (GSH-Px) activity levels and polymorphonuclear leukocytes (PMNs) numbers, lung tissue samples were taken before CPB and 5 min after removing the cross clamp. In addition, alveolo-arterial oxygen difference (AaDO(2)) for tissue oxygenation was calculated by obtaining arterial blood gas samples. RESULTS: MDA levels before CPB increased from 41.72+/-21.00 nmol/g tissue to 66.71+/-13.44 nmol/g tissue in group I and from 43.44+/-5.16 nmol MDA/g tissue to 53.22+/-10.95 nmol MDA/g tissue in group II after cross clamp removal (P=0.001 and P=0.021, respectively). The increase in group II was found to be significantly lower than group I (P=0.048). With the initiation of reperfusion, GSH-Px activity decreased in group I from 3.05+/-0.97 to 2.31+/-0.46 U/mg protein (P=0.015) whereas GSH-Px activity in group II decreased from 3.18+/-1.01 to 2.74+/-0.81 U/mg protein (P=0. 055). This decrease in the group II was less than group I (P=0.049). AaDO(2) significantly increased in the group I and II (P=0.012 and P=0.020, respectively), but elevation in the group I was significant than in the Group II (P=0.049). In histopathological examination, it was observed that neutrophil counts in the lung parenchyma rose significantly following removal of cross clamp in both groups (P=0. 001). The increase in group I was significantly larger than in group II (P=0.050). CONCLUSION: Results represented in our study indicate that addition of aprotinin (2 million units) into the prime solution during CPB can reduce lung reperfusion injury.
