Cerebral And Systemic Effects Of Dexamethasone In Cardiac Valve Replacement Patients Undergoing Cardiopulmonary Bypass

Objective:To observe the protective effect of dexamethasone(DXM) on cerebral injuries induced by inflammation cytokines in cardiac valve replacement patients undergoing cardiopulmonary bypass(CPB).Methods:30 patients were randomized to received a single shot of 0.5 mg/kg dexamethasone(dexamethasone group) or placebo(control group) 60 minutes before operation.Neuropsychological tests(MMSET) were administered preoperatively and on the sixth postoperative day.Plasma levels of TNF-α,IL-1β,S100βand NSE were measured at the following times:before the dexamethasone or placebo were administered(T1),before starting CPB(T2),the end of CPB(T3),immediately after operation(T4),24h after skin closure(T5) and 48h after skin closure(T6).Results: Preoperative and intraoperative characteristics of patients were not different between groups.The Postoperative sixth day MMSET scores in the dexamethasone group were significantly higher than in the placebo groups(P＜0.05).Both the plasma concentration of TNF-α,IL-1β,S100βand NSE were upregulated after T2(P＜0.05) and almostly resume to normal level at T6.The plasma concentration TNF-α,IL-1β,S100βand NSE in dexamethasone group were lower than in placebo group(P＜0.05).Conclusion:Dexamethasone may reduce the injury of cerebral function.after cardiopulmonary bypass by inhibitting the release of proinflammatory cytokine.