support (see Table 1), although the larger the cannula, the greater the flow that
can be achieved.
In the percutaneous approach, an ultrasound is usually used to identify the vein.
An introducer needle is used to access the vein under ultrasound guidance
followed by placement of wire through the needle. The wire can be confirmed by
fluoroscopy (the preferred approach at our institution) or echocardiography.
Systemic heparin should be administered after placement and confirmation of the
guidewire. After incising the skin next to wire, a series of dilators are placed
gently over the wire under guidance (fluoro or echo). Generous lubrication is
often necessary to place the dilators through the skin and subcutaneous tissues.
Aggressive force, however, should not be used to advance the dilators. The
ultimate cannula is then placed over the guidewire, with subsequent removal of
the wire. An extension is used to connect to the ECLS circuit and de-bubbling of
the circuit is performed prior to starting ECLS.
Transthoracic cannulation may be appropriate in the post-cardiac surgery
patient with cardiac and/or pulmonary dysfunction, or a patient with septic shock
to allow for increased blood flow with the larger cannulas that can be placed.[ 6 ]
In general, however, access for ECLS is provided via extrathoracic cannulation.
The first choice of venous access is the internal jugular vein since it is a large
vein which provides easy access to the right atrium via a short cannula. The
femoral vein is the second choice for venous drainage access during ECLS and
the first for reinfusion during VV support. Drainage via the femoral vein is