Background
We investigated the cytokine response during coronary artery bypass grafting (CABG) surgery with and without cardiopulmonary bypass (off-pump) and the effect on patient's outcome in the early postoperative period.
Methods
Eighteen patients were studied, 9 patients undergoing off-pump surgery (group 1) and 9 patients with CPB (group 2). Demographic and preoperative characteristics were comparable in both groups. Plasma levels of TNF-α, IL-6, IL-8, IL-10, IL-4, tumour necrosis soluble receptors-1 (TNFsr-1) and tumour necrosis soluble receptors-2 (TNFsr-2) were measured before skin incision (0), before revascularization (1), after revascularization (2), 2 h (3) and 24 (4) hours after skin closure. Levels of myocardial enzymes were also measured in the first postoperative morning.
Results
Serum levels of TNF-α and IL-8 increased in group 2 at 3 and 4 more than at 0 (0.05). IL-6 increased in both groups with higher levels in group 2 than in group 1 at 3 (773 ± 331 vs 315 ± 189 pg/ml;  < 0.05). IL-10 was higher in group 2 than in group 1 at 2 (115 ± 119 vs 13 ± 4 pg/ml;  < 0.001) and at 3 (212 ± 171 vs 31 ± 29 pg/ml;  < 0.05). At 3 levels of TNFsr-1 and TNFsr-2 were higher in group 2 than in group 1 (TNFsr-1 4858 ± 1325 vs 2089 ± 584 pg/ml;  < 0.01 and TNFsr-2 4971 ± 63 vs 3801 ± 738 pg/ml;  < 0.05). Production of IL-4 did not increase in neither group. The length of ICU stay was less in group 1 than in group 2 (52 ± 33 vs 26 ± 11 h;  < 0.05) as well as was the length of hospital stay (7.1 ± 0.4 vs 5.3 ± 0.5 days;  < 0.001).
Conclusion
Off-pump procedure evoked a lower cytokine response than CABG with CPB. This minimised myocardial damage and shorten the stay in the ICU and the hospital.