Venous cannulation is usually done after arterial cannulation. This is done to allow suction bypass in case of any problems. Cannulation can be either via the RA or selectively in the SVC and IVC . RA cannulation can be bi/tricaval (In the case of a left SVC) or two stage single cavo-atrial cannulation.The innominate vein can also be used for cannulation.Peripheral cannulation via the femoral vessels or internal jugular vein can be alternate sites of cannulation.
Inflow cannulation will also include non venous cannulation that would include LA cannulation and LV apical cannulation
Trans atrial SVC cannulationEdit
This is usually via the RA appendage or via a purse string in the RA just below the SVC. While placing the cannula into the SVC care must be taken while placing the cannula to avoid hooking it on a natural ridge between the SVC and the RA . This can frustrate attempts in entering the SVC . This can be avoided by grazing the tip of the cannula along the lateral RA wall allowing it to slip into the SVC. Placing the cannula low down near the SVC RA junction can be advantageous when using shorter tipped cannulae to prevent slippage of the cannulae. If there is a sinus venosus ASD the SVC cannula can be inadvertently placed via the ASD into the LA instead of the SVC so it is important to see/palpate the entry of the cannula into the SVC.