Venous drainage - gravity or assisted?

Abstract

Since the early start of cardiopulmonary bypass, vascular access has been recognized as a main variable for obtaining optimal blood flow during cardiopulmonary bypass. In particular, venous drainage can limit the maximum flow as the wide, low-resistance, collapsible veins are connected with smaller stiff cannulas and tubing. Due to the introduction of long venous cannulas for minimally invasive cardiac surgery and the desire to limit hemodilution during cardiopulmonary bypass, more and more centers have started using assisted venous drainage techniques. This article gives an overview of these techniques, with their respective advantages and disadvantages.

Cannulation Strategies and Pitfalls in Minimally Invasive Cardiac Surgery

“…Modern three-stage cannulas provide excellent drainage and decompression of the right heart with the aid of a kinetic drainage assist device. [1][2][3][16][17][18][19] The latter is an important element of myocardial protection during cardioplegic arrest. [2][3][16][17][18][19] The right femoral vein is favored because of the straighter alignment with the inferior vena cava.…”

“…[1][2][3][16][17][18][19] The latter is an important element of myocardial protection during cardioplegic arrest. [2][3][16][17][18][19] The right femoral vein is favored because of the straighter alignment with the inferior vena cava. 2,3,20,21 TEE is used to position the tip of the cannula in the superior vena cava, which is important for optimal drainage.…”

“…2,3,20,21 TEE is used to position the tip of the cannula in the superior vena cava, which is important for optimal drainage. 2,3,12,19,20 This is effective for most MICS procedures including those involving the mitral valve. 2,3,16 Similar to cannulation of the femoral artery, the cannula may be inserted open or percutaneously (Figure 4).…”

“…However, MICS AVR cases can still be performed by placing a low-profile cannula into the right atrium directly through the chest incision. 2,3,[17][18][19] Potential complications include perforation of the IVC during cannula insertion and entrapment of air with airlock during CPB. In addition, the length of the femoral vein cannula usually creates increased resistance to effective drainage.…”

“…A vacuum-assisted device is often used in MICS cases to overcome this downfall and prevent any air entrapment during CBP. 2,3,[17][18][19]…”