Change Of Plasma Cytokines In Cardiac Surgery Under Cardiopulmonary Bypass

BackgroundIn morden era the mobility and mortality rate of open heart surgery have been decreased greatly for the improvement of cardiovascular surgery technique and the introduction of cardiopulmonary bypass.But for many factors during CPB,either material dependent(the exposure of blood to nonphysiologic surfaces and conditions) or material independent (surgical trauma,ischemia-reperfusion to the organs,changes of body temperature,and release of endotoxin). Cardiopulmonary bypass can induce complement system activation, lead initially to systemic inflammatory response(SIRS) including the release of inflammatory mediators such as cytokines. And even induces multiple6organs failure(MOSF).So how to elevate the open heart surgery safety and diminish the complications induced by CPB had been a study focus .However the precise mechanism of the change of cytokines involved in CPB and the role of cytokines in these responses had not yet been clear established.This study wanted to demonstrate the level and the regular of cytokines change and the relation between them by assay the 11 mitral valve replacement(MVR) cases' plasma level of cytokines (IL-6,IL?,IL-10,TNF). We hope it would be useful to develop effective therapeutic interventions to attenuate these problem occurred in CPB. Material and methodFrom Jan, 1999 to Dec,2001 we randomly selected 11 cases with rheumatic mitral valve disease who need undergo mitral valve replacement(MVR) under CPB.And excluding immune diseases and intake of immune drugs in last half a year. No coronary artery disease ,myocardial infarction in recent Smonths or hepatic/renal failure history.All patients received standard anesthetic.Moderate hypothermic CPB with the same roller-pump arterial drive system(San8000).Using same hollow-fiber membrane oxygenator(Baxter).All the patients use the same cold cardioplegicblood.heparin 2.5~4mg/Kg.And we finished these operations by mid-sternal incision.continuous suture in MVR. Experiment method and assay indexWe sampled 5ml venous blood at these points(Pre-op,Before-aortaclamped,During CPB,10mins after aorta declamging ,lh after aorta declamping,2h after aorta declamping,4h after aorta declamping,24h after aorta declamping).We withdrawal the blood serum after centrifugated and determinate the level of IL-6,IL-8,IL-10,TNF by using ELISA method. Statistical processingAll values were processed by t-Test and expressed by mean 盨E. when p<0.05 or less was considered to indicate statistical significance . All statistical process were completed via SPSS (V10. 0). ResultsAll 11 cases were got smoothly anesthesia , surgery and CPB . There was a significant elevation of the plasma of IL-6, IL-8,IL-10, TNF level in our study.But there was no significant difference between Pre-op and Before-aorta clamping(p > 0.05).The level of these cytokines were elevated after aorta clamped especially after aorta declamped . And IL-6, IL-8, IL-10 got to the peak at 2 hours after aortadeclamped(p< 0.01). TNF still remain a high level at 24 hours after aorta declamped (p< 0. 01). There were relativity among IL-6, IL-8, IL-10 by Spearman's analysis(p < 0. 01). Conclusion and commentIn our study there were significant elevate of plasma level of IL-10, as well as IL-6 and IL-8, increased during CPB, especially 2 hours after aorta declamped .and plasma TNF remain at a high level at 24 hours after aorta declamped. It demonstrated that there was rise of plasma proinflammatory cytokines , but also had elevate of antiinflammatory cytokine during mitral valve replacement under CPB. It may make a balance of antiinflammatory/proinflammatory cytokines.