CPC: cerebral performance then class; ECLS: extra corporeal life support; ICU: intensive care unit.Data collectionAccording to French legislation at the time of the study and given the observational retrospective nature of the study, no ethical committee was requested and thus no informed consent was obtained from the patients. At the time of ECLS implantation the focus was specifically on hemodynamic (including electrocardiographic and echocardiographic), neurologic, respiratory, renal, liver, and hematologic data. Measured physiological variables were used to calculate the Simplified Acute Physiology Score (SAPS II)  and the Sequential Organ Failure Assessment (SOFA) score . The toxicological screening was recorded and drugs classified as with or without cardiotoxic effect or membrane stabilizing activity (MSA).
In addition, the clinical course of each patient during hospitalization was recorded. Vascular, neurologic, hemorrhagic, renal, and perfusion system complications were documented. The neurologic outcome at hospital discharge was assessed according to the cerebral performance class (CPC) categories : CPC 1 = good cerebral performance, CPC 2 = moderate cerebral disability, CPC 3 = severe cerebral disability, CPC 4 = coma or vegetative state, and CPC 5 = brain death or death.Cannulation techniqueDevice description, cannulation technique, management, and weaning from ECLS were previously reported in detail . Briefly, the hardware for cardiopulmonary circulation consisted of a Biomedicus portable system (Medtronic, Inc, Minneapolis, MN, USA) incorporating a centrifugal pump console and a water pump system.
The closed ECLS circuit consisted of pre-connected polyvinyl chloride tubing (Medtronic, Inc, Minneapolis, MN, USA) including a constrained vortex pump chamber, a hollow-fiber membrane oxygenator with an integral heat exchanger (Maxima PRF, Medtronic, Inc, Minneapolis, MN, USA), and a flow probe. All components were heparin-coated (Carmeda Bioactive Surface-coating). The cannulae were Biomedicus (17 F to 25 F), according to the size of patients.Once the decision to implant ECLS support was made, the circuit was quickly primed with normal saline. Heparin was administered to the patient at 50 UI/kg immediately before cannulation of the vessels. The activated clotting time (ACT) was kept between 150 and 200 seconds at full-flow assistance.
Peripheral femorofemoral cannulation was surgically set up using a modified Seldinger technique. Because cannulation-related limb ischemia was a major problem when we began this technique, additional distal limb perfusion was inserted Drug_discovery to avoid severe leg ischemia. The distal tip of the arterial cannula was positioned in the common iliac artery or distal abdominal aorta, whereas the tip of the venous cannula was set in the right atrium under echocardiographic guidance and confirmed by chest radiograph.