外科心脏教材教学稿件.ppt

Surgical Treatment of Heart Disease ;Contents;Cardiopulmonary Bypass;Elements of cardiopulmonary Bypass. 1. Pump Oxygenator Oxygenation of the blood. Elimination of Carbon dioxide. Gas exchange occuring the blood-gas interface. ;2.Arterial pump Roller pump (nonpulsative flow) Centrifugal pump 3.Venous reservor Stores excess volume Siphonage of blood by gravity 4.Heat exchanger Regulate the temperature Blood returning Cardiotomy Suction lines;. 5.Cannulation Aortic root A. Cannula. Femoral A V. Cannula. Through R. Atrinum → each Vena Cava. Single V. Cannula → left side procedure. Single L.Cavoatrial (two-stage)V. Cannula. ; ;The connection of CPB;Myocardial protection;General cardioplegia solution composition;Method of perfusion Antegrade Retrogrde Coronay A Ostia Single Dose Continuous Intermittent ;Temperature control Mild hypothermia (25-32℃) * most commonly used * doubles safe ischemic time Moderate hypothermia(17-25℃) Profound hypothermia(≤16℃) *Complex congenital cardiac lesions (infants) * Aortic arch surgery (adults) Filtration;Warm heart Surgery Based on the Concept that delivery of Continuon.Northothemic cardioplegia causing electromechanical arrest of myocardim accounts for 90% of reduction in oxygen requirements.;Preconditioning Murry 1986 first described IPC Ischemic preconditional regarded as the most powerful form of endogenous myocardial Alkhlaif 1994 first clinical trial ;Method: Two cycles of 3 min ischemia by occulusion of vena cava Aortic cross-claming followed by 2 min reperfusion under CBP. Myocardial protection effect IPC protect against myocardiatissue necrosis to limit.infarct size. Induce favourable metabolic changes preservation of ATP attenuation of intracellar acidosis. Reduction of lactate Redu. in myocardial glycogen use Redu arrhythmias. ; Heart anato