Effect of low-dose methyl prednisolone on serum cytokine levels following extracorporeal circulation
The systemic inflammatory response to cardiopulmonary bypass (CPB) is associated with increased production of cytokines. This systemic inflammatory response characterized by the activation of interleukin-6 (IL-6) and interleukin-8 (IL-8) during and after CPB is well documented. A prospective randomized double-blind study was performed so as to understand the effects of low-dose methyl prednisolone sodium succinate (MPSS) on the circulating levels of serum cytokines and clinical outcome. Twenty patients were randomly divided into two groups on the basis of the administration of low-dose(1 mg/kg) MPSS in = 10) and placebo in = 10) into the pump prime solution. All patients were scheduled to undergo a primaryelective coronary artery bypass grafting operation. Patients receiving concurrent corticosteroids salicylates dipyridamol or anticoagulants were excluded from the study. Other exclusion criteria were concurrent chronic obstructive pulmonary disease chronic renal failure insulin-dependent diabetes congestive cardiac failure peptic ulcer history prior cardiac operations recent tin a one-month period) myocardial infarction and steroid dependency. Mild systemic hypothermia (30-32 degrees C rectal) was assured during the CPB. Four blood samples were drawn from the radial artery catheter immediately before starting CPB (T1) following protamine administration (T2) and at 24 (T3) and 48 h (T4) after completion of CPB. In each sample creatine kinase-myocardial band (CK-MB) white blood cell (WBC) IL-6 and IL-8 levels were measured. IL-6 and IL-8 concentrations were measured by enzyme immunoassay and enzyme-linked immunoabsorbant assay methods.