Serum levels of IL-1, IL-6 and tumour necrosis factors in patients undergoing coronary artery bypass grafts or cholecystectomy

Abstract

Plasma levels of biologically active IL-1, tumour necrosis factor (TNF) and IL-6 were measured before, during and after coronary artery bypass graftings (CABG) (n = 9) and cholecystectomy (CHO, n = 9), and in normal controls (nine healthy volunteers). Mean pre-operative IL-1 concentration in four of the nine CABG patients was 0.452 + 0.03 ng/ml, significantly (P less than 0.001) higher than that of the other five (0.045 +/- 0.009 ng/ml), CHO patients (0.035 +/- 0.005 ng/ml) and controls (0.029 +/- 0.008 ng/ml). Three of the four patients with high pre-operative IL-1 had functional capacity IV, while the other five had functional capacity IIa or IIb. Slight IL-1 elevation after anaesthesia, followed by reduction after initiation of bypass, elevation on completion of surgery and reduction to basal levels after 7 days was found in patients undergoing CABG. Mean basal TNF levels of CABG and CHO patients did not differ, but were higher than those of controls (2.85 +/- 0.5 ng/ml for CABG, 2.05 +/- 0.06 ng/ml for CHO, 0.72 +/- 0.07 ng/ml for normals, P less than 0.001). A unique kinetics of release during CABG was observed also for TNF. Mean pre-operative IL-6 levels were normal (50 +/- 3 ng/ml for CABG, 50 +/- 0.5 ng/ml for CHO and 65 +/- 10 ng/ml for controls). Gradual elevation to a mean peak of 725 +/- 100 ng/ml on completion of CABG was observed as compared with 275 +/- 50 ng/ml in CHO (P less than 0.01). On the seventh post-operative day mean IL-6 levels returned to normal. Two patients with post-operative low-grade fever (38 degrees C) had high, late cytokine levels. One of these two patients had leucocytosis, sterile discharge from the operative wound and was diagnosed as suffering from the Dressler syndrome. In this study elevated cytokine values and unique kinetics of release into the serum were found in patients undergoing CABG.