Elevation of cytokines during open heart surgery with cardiopulmonary bypass: participation of interleukin 8 and 6 in reperfusion injury.

Myocardial ischaemia is one of the major causes of low output syndrome during open heart surgery. Injury associated with ischaemia and reperfusion has been considered to result, in part, from the action of neutrophils, the interaction of neutrophils with vascular endothelial cells, and the effects of cytokines which are mediators that induce and modify reactions between these substances. We investigated cell injury in relation to the concentrations of interleukins 6 and 8 (IL-6 and IL-8), which have recently received attention as neutrophil activators. Neutrophil counts, granulocyte elastase (GEL), IL-6, IL-8, tumour necrosis factor-alpha (TNF-alpha), CK, and CK-MB concentrations were determined serially in 11 patients undergoing open heart surgery with cardiopulmonary bypass (CPB). Neutrophil counts (mean +/- SD 2717 +/- 2421 microliters-1 preoperatively) peaked 60 min after declamping the aorta at 7432 +/- 4357 microliters-1 (P < 0.01) and remained elevated 7136 +/- 5194 microliters-1 at 180 min (P < 0.01). Plasma GEL level (168 +/- 71 micrograms.L-1 preoperatively) peaked at 1134 +/- 453 micrograms.L-1 120 min after declamping of the aorta (P < 0.01) and remained elevated, 1062 +/- 467 micrograms.L-1, after 180 min (P < 0.01). Serum IL-6 level (118 +/- 59 pg.ml-1 preoperatively) peaked at 436 +/- 143 pg.ml-1 60 min after declamping of the aorta (P < 0.01) and remained elevated, 332 +/- 109 pg.ml-1, after 180 min. Serum IL-8 level (37 +/- 44 pg.ml-1 preoperatively) peaked at 169 +/- 86 pg.ml-1 at 60 min after declamping of the aorta (P < 0.001) and remained elevated at 113 +/- 78 pg.ml-1 180 min after declamping of the aorta.(ABSTRACT TRUNCATED AT 250 WORDS)