外科学教学课件：体外循环

1、Cardiopulmonary Bypass,Congenital heart disease,Tetralogy of Fallot 6 years old,15 kg weight. cyanosis,clubbing fingers. wouldnt grown-up unless recieved cardiac surgery,To repair the cardiac defects Bloodless field Motionless field Stop the motion of the heart and lungs,Bloodless? Motionless? Life

2、maintenance,Cardiopulmonary Bypass,1 Definition 2 Basical equipments 3 Essential steps 4 Clinical application 5 Pathophysiology 6 Postoperative treatment,Drains venous blood from the right atrium or vena cava by the cannula inserted into the venous system.Finishs gas exchange process including oxyge

3、n and carbon dioxide by the artifial lung(oxygenator) to change the oxygen poor venous blood into the oxygen rich arterial blood.Pumps oxygenated blood back to the body by the artificial heart(pump) via arterial cannula to remain the living of the all the other organs of the body except the lung and

4、 the heart. Provides a limited 2-3 hours time during which the lung and the heart are not working for cardiac surgeon to open the heart and finish a operation precisely with bloodless and motionless field,Cardiopulmonary Bypass,By this way,the function of the lung and heart had been taken over by th

5、e extracorporeal circulation equipments. Provide the desired bloodless, motionless operative field and still supply all the other organs of the body with oxygen and nutrient-rich blood,Heat exchanger,Summary for CPB Purpose: 1) To provide a bloodless, motionless field for heart surgery 2) Rest of bo

6、dy perfused while heart and lung stopped Methods: 1) Drain out venous blood 2) Oxygenated by artificial lung 3) Oxygen-rich blood pumped back by artificial heart,History Landmark in cardiac surgery! Western countries in 1953 China in 1958 The hospital here 1963 1979,John H. Gibbon,吴英恺,1 Definition 2

7、 Basical equipments 3 Essential steps 4 Clinical application 5 Pathophysiology 6 Postoperative treatment,Basic equipments 1 artificial heart (blood pump) 2 artificial lung (oxygenator) 3 temperature exchanger 4 filter 5 tubes or cannulas,Artificial hypothemia,Using bionics principle of hibernation，l

8、owering the body temperature can strengthen the tolerance ablility for hypoxia. Decreasing 1 of the body temperature can reduce oxygen consumption by 5%-6%. Decrease the body temperature to 28 -20 , the metabolization will be reduced to 50%-80%. Therefore, low temperature can enhance the body tolera

9、nce to hypoxia. Combine the cardiopulmonary bypass and hypothermic anesthesia together widely used in the treatment of heart disease for open intracardio surgery,blood pump,oxygenator,temperature exchanger,tubes,1 Definition 2 Basical equipments 3 Essential steps 4 Clinical application 5 Pathophysio

10、logy 6 Postoperative treatment,Typical process for open heart surgery 1 Anesthesia 2 Supine position 3 Median sternotomy,4 Incision of the skin and subcutaneous,5 Sternum divided by saw,5 Thymus isolated 6 Incision of pericardium,7 Heart and great vessels exposed 8 Heparinize 9 Exterior exploration

11、Chest opened by sternotomy,10 Cannulations for Aorta,SVC,IVC 11 Connect cannulations to cardiopulmonary bypass machine the bypass system established 12 Start the bypass machine and hypothermia 13 Aortic cross-clamp placed cardioplegia injected the heart arrested,14 Open the heart . exploration and o

12、peration,Cardiopulmonary Bypass Technique,Cardiopulmonary Bypass Technique,Arterial & Venous Cannulation,Myocardial Protection,Strategies: 1 Hypothermia cold perfusate surface cooling 2 Cardioplegia K+ diastolic arrest Intermittent perfusion,Myocardial Protection,Cardioplegia: Route of administratio

13、n,Antegrade,Retrograde,CPB under going,Nonpulsatile / pulsatile flow C.O. - 2-2.5 L/min/m2,15 Re-warming de-air release aortic clamp heart resuscitation heart beating again 16 Heart incision suture 17 Off pump gradually remove the pipelines 18 Administration of protamine neutralize against heparin r

14、estore clotting function 19 Sternal fixation with wire 20 Close the skin incision,Anesthesia,Median sternotomy,Incision of pericardium,Exterior exploration,Heparinize,Cannulations for Aorta,SVC,IVC,Start the bypass machine and hypothermia,Aortic cross-clamp placed Cardioplegia injected,Intracardiac

15、exploration and open-heart operation,Re-warming,de-air,release aortic clamp,heart resuscitation,Off pump gradually,Neutralize against heparin restore clotting function,Sternal fixation with wireClose the skin incision,1 Definition 2 Basical equipments 3 Essential steps 4 Clinical application 5 Patho

16、physiology 6 Postoperative treatment,Clinical application: All the operations need open the heart Congenital heart disease Cardiac valve disease Coronary artery disease Great vessel disease Extended radical operation for various chest tumor,Congenital heart disease,Cardiac valve disease,Coronary art

17、ery disease,Great vessel disease,1 Definition 2 Basical equipments 3 Essential steps 4 Clinical application 5 Pathophysiology 6 Postoperative treatment,Pathophysiology after bypass 1 Metabolic changes: acidosis and alkalosis 2 Electrolytes turbulence: hypokalemia 3 Blood damage: blood cell damage,coagulation disorder 4 Renal or lung function decrease or damage,1 Definition 2 Basical equipments 3 Essential steps 4 Clinical application 5 Pathophysiology 6 Postoperative treatment