Clinical study of complement activation during cardiopulmonary bypass--analyses of complement activation pathway and transpulmonary leukosequestration
Miyamoto, Y.
Nihon Kyobu Geka Gakkai 34(12): 2055-2061
1986
ISSN/ISBN: 0369-4739 PMID: 3559305 Document Number: 285020
Complement activation during cardiopulmonary bypass (CPB) has been postulated to have deleterious effects on the lung postoperatively. This clinical study was undertaken to investigate the complement activation pathway during CPB, transpulmonary leukosequestration and complement activation in the lung itself after reestablishment of pulmonary circulation. A prospective study was made in 21 adult patients undergoing open heart surgery. Blood samples were obtained before and 10, 30, 60 and 120 min after starting CPB. Further samples from the pulmonary artery (PA) and left atrium (LA) were obtained a few minutes after defibrillation and also after termination of CPB. A rapid decrease in total hemolytic activity (CH50) to 81 .+-. 9% of pre-values occurred 10 min after starting CPB, (p < 0.01), and subsequently, no further changes were seen. Hemolytic activities complement components also fell significantly to 81 .+-. 7% (C4), 84 .+-. 8% (C2), 83 .+-. 9% (C3) and 86 .+-. 8% (C5) 10 min after starting CPB (p < 0.01). C3a, C4a and white blood cells (WBCs) significantly increased during CPB. Reestablishment of pulmonary circulation after defibrillation resulted in a significant decrease (p < 0.001) in WBCs in LA (5310 .+-. 3650/min3) compared with those in PA (7940 .+-. 3740/mm3). C3a levels (1016 .+-. 629 ng/ml) in LA were significantly (p < 0.05) higher than those in PA (701 .+-. 525 ng/ml). No difference in C4a levels was found in PA and LA. Furthermore, after termination of CPB, no difference existed in PA and LA values. It was concluded that: 1) complement during open heart surgery was activated by CPB itself and by the reestablishment of pulmonary circulation, 2) transpulmonary leukosequestration occurred at reestablishment of pulmonary circulation 3) complement activation during CPB occurred via both classical and alternate pathways, and 4) complement activations in the lung itself probably occurred via the alternative pathway.