APROTININ ENHANCES THE ENDOGENOUS RELEASE OF INTERLEUKIN-LO AFTER CARDIAC OPERATIONS

Background. Cardiopulmonary bypass (CPB) is characterized by the syste mic release of proinflammatory cytokines, such as tumor necrosis facto r-alpha and the interleukins 1 and 6, as well as endogenous antiinflam matory cytokines, including interleukin-10 (IL-10). Glucocorticoids re duce tumor necrosis factor-alpha plasma concentrations while enhancing IL-10 plasma concentrations after CPB. Aprotinin, a serine protease i nhibitor used primarily to reduce blood loss after CPB, reduces CPB-in duced proinflammatory cytokine tumor necrosis factor-alpha release sim ilarly to glucocorticoids. This study evaluates the effect of full-dos e aprotinin on the plasma concentrations of IL-10 after CPB. Methods. Twenty adults were randomized into a control (group C, n = 10) and a f ull-dose aprotinin-treated group (group A, n = 10). Plasma levels of I L-10 were measured by enzyme-linked immunosorbent assay technique at b aseline (before anesthetic induction), and at 1 and 24 hours after CPB termination. Results. A significant (p < 0.05) increase of IL-10 occu rred in both groups at 1 and 24 hours after termination of CPB when co mpared with the same group at baseline. In group A, the increase in IL -10 was significantly greater than in group C (p < 0.05) at 24 hours a fter CPB. Conclusions. These results demonstrate an endogenous antiinf lammatory response generated after CPB, characterized by IL-10 release , that is enhanced by aprotinin therapy. This study demonstrates a uni que antiinflammatory activity of aprotinin that may be of clinical sig nificance. (C) 1998 by The Society of Thoracic Surgeons.