ECMO-/ECLS

while the axillary artery is difficult to dissect and cannulate. In patients under 5
years of age, the femoral and axillary arteries are of insufficient size to provide
arterial access: therefore, the iliac artery is the preferred site after the carotid
artery. [ 5 ] Distal perfusion of the lower extremity arterial circulation is required
when the femoral artery is cannulated, although distal perfusion is typically not
required after cannulation and ligation of the iliac artery in young children.
In patients supported using venoarterial ECLS using the femoral artery,
use of a distal reperfusion cannula has been described to improve limb perfusion.
A percutaneous distal femoral artery cannula, placed distal to the arterial
reinfusion cannula for ECLS, can be used in children.[ 10 ] A cutdown on the
posterior tibial artery has also been successfully used to provide retrograde blood
flow to the limb.[ 11 ] Limb reperfusion must be provided within 6 hours of the
ischemic event (arterial cannulation) to prevent irreversible neuromuscular
damage to the leg.
C. Monitoring
Once in place, the cannulas are connected to the ECLS circuit and
cardiopulmonary bypass is initiated. Flow is increased over the ensuing 10- 15
minutes. Once on extracorporeal support there typically is rapid cardiopulmonary
stabilization. All paralyzing agents, vasoactive drugs, and other infusions are
slowly discontinued during use of veno-arterial support, although some
vasopressor support may still be necessary when veno-venous bypass is
utilized.[ 12 ] Ventilator settings are adjusted to minimal levels in order to allow the
lung to rest and seal any air leaks secondary to barotrauma. Application of