RESUMO
Plasma concentrations of tumor necrosis factor α (TNFα), interleukin-1β (IL-1β) and interleukin-6 (IL-6) were measured successively during and after open heart surgery (13 cases). Plasma concentrations of TNFα did not increase during surgery but increased gradually after the 1st operative day reached the maximum level at the 7th operative day (128±15pg/ml, which was a 3-fold increase compared with the previous value). Plasma concentrations of IL-1β remained at the previous level during surgery and increased only once at 6 hours after operation. Conversely, plasma concentrations of IL-6 increased dramatically during cardiopulmonary bypass (CPB) reaching a peak at the end of CPB (260±200pg/ml, which was a 15-fold increase over the previous value) and recovered to previous values rapidly thereafter. Plasma IL-6 concentrations changed rapidly during surgery, while plasma concentrations of TNFα and IL-1β did not increase sharply. This may indicate that IL-6 may play a role as a mediator of acute inflammatory reaction.