[Interleukin-6 and glucocorticosteroid responses to cardiopulmonary bypass]

The responses of interleukin-6 (IL-6), ACTH, cortisol, WBC, CRP to cardiopulmonary bypass (CPB) were studied in 5 patients who underwent elective CABG (N = 4) and AVR (N = 1). IL-6 started to increase from 3 h after the beginning of the operation at which aortic clamp was removed and reached a peak after 4 h at which CPB was withdrawn. ACTH also reached a peak after 4 h. The increase of cortisol started from 2 h when aorta was clamped, which was earlier than that of IL-6. IL-6 and ACTH fell sharply to pre-CPB levels before first postoperative day (1 POD) while cortisol remained high postoperatively. CRP level and WBC counts were maximum at 2 POD. The results suggest that the cortisol response to CPB is not only caused by IL-6, but also by other factors, such as IL-1 and TNF.