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The extracorporeal membrane oxygenation (ECMO) is an extracorporeal procedure used for patients with cardiac or respiratory failures who do not react to conventional therapy (Harry Anderson, 1993; Paolini, 1994; Smith, 2001). Furthermore, it is also adopted as a post-operative circulation support after cardiac surgeries and as a prolonged but temporary support for weaning from the cardiopulmonary bypass (CPB) (Doll, 2004). The main clinical complications of the ECMO-treated patients are cerebral injuries and infarction, which can cause death (Doll, 2004; Risnes, 2005). Indeed, hemolysis, thromboembolic events and internal blending are the major complications related to the artificial organs (Goubergrits, 2006), and, above all, to the mechanical shear stress. To overcome them, anticoagulants must be administered even if they worsen the performance of the devices (Goubergrits, 2004).
As reported in (Ji, 2006), the pulsed perfusion during the extracorporeal circulation is healthier compared to the normal one, that is characterized by constant/linear flow. In 1977 the intra-aortic balloon pump (IABP) was proposed by (Bregman, 1977) as a useful device to provide pulsatile flow during CPB. The principal component of this mechanical support is a polyethylene balloon placed in the aorta after the left subclavian artery and before the iliac bifurcation, which inflates/deflates according to the cardiac cycle or setting the assistance level when there is no heart activity, such as during CPB or ECMO. Recently, some studies have highlighted different benefits of IABP-induced pulsatility during ECMO (Madershahian, 2009; Madershahian, 2011; Petroni, 2014; Yang, 2014).
Based to our knowledge, there is little information regarding the hemodynamic pattern in aorta and its incidence on clinical complications and, so, on illness development during normal/constant ECMO and IABP-induced pulsed ECMO. Therefore, a detailed analysis is necessary.