使心臟處於無血流進出、靜態的狀態，以利於心臟手術的執行 !

體外循環(cardiopulmonary bypass)

當心臟處於無血流狀態時 如何不發生心肌缺氧??

2.心肺機(泵)1.建置管路 +

體外循環的角色

• 靜脈端血流引流至儲存槽

• 進行血液氧合

• 調整電解質及其他化合物

• 調控血液溫度

• 送返血液至動脈端

• 輸送心臟麻痺液

動脈管路設置

Figure 1: Double-arterial cannulation technique. Two equally sized soft cannulas inserted into the innominate artery and the descending aorta are linked via a Y-connector.

靜脈管路設置

b. LV vent placed via the right superior pulmonary vein:A cannula is inserted at the junction of the right superior pulmonary vein with the left atrium and then threaded through the left atrium and MV into the LV.This method is used during aortic and MV surgery (especially in the presence of aortic regurgitation) and for patients with poor LV function.

排放 :血液/氣體

心臟麻痺液灌流系統

a. Aortic root vent (one limb of the antegrade cardioplegia cannula): This is the most common technique used during coronary artery bypass graft (CABG) surgery. Suction is applied to the antegrade cardioplegia cannula (directly or via a side branch). Aortic root venting of the LV is only effective when the aorta is cross-clamped, when antegrade cardioplegia is not being administered, and when the aortic root is not opened.

排放 : 氣體/血液

Aortic cannulation

Venous cannulation

aortic cross clamp

Cardioplegia system

Vent placed

心肺機(泵)

Components of the CPB circuit

1. Venous Reservoir(靜脈血儲蓄槽)

2. Arterial Pump(動脈泵)2a, Centrifugal Arterial Pump2b, Roller Arterial Pump

3. Oxygenator(氧合器)

4. Arterial Line Filter(動脈端過濾器)

1

2

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b. LV vent placed via the right superior pulmonary vein:A cannula is inserted at the junction of the right superior pulmonary vein with the left atrium and then threaded through the left atrium and MV into the LV.This method is used during aortic and MV surgery (especially in the presence of aortic regurgitation) and for patients with poor LV function.

a. Aortic root vent (one limb of the antegrade cardioplegia cannula): This is the most common technique used during coronary artery bypass graft (CABG) surgery. Suction is applied to the antegrade cardioplegia cannula (directly or via a side branch). Aortic root venting of the LV is only effective when the aorta is cross-clamped, when antegrade cardioplegia is not being administered, and when the aortic root is not opened.

c. LV vent placed directly through the LV apex: This is rarely used today because of difficulty in positioning and bleeding after removal.

d. Vent placed through the left atrial appendage or the top of the left

atrium (into either the left atrium or LV). Rarely used.

Arterial cannula

Venous cannula

Antegrade cardioplegia cannulaRetragrade cardioplegia cannula

LV vent