In Vivo Hemodynamic Performance Evaluation of Novel Electrocardiogram-Synchronized Pulsatile and Nonpulsatile Extracorporeal Life Support Systems in an Adult Swine Model

The primary objective of this study was to evaluate a novel electrocardiogram (ECG)-synchronized pulsatile extracorporeal life support (ECLS) system for adult partial mechanical circulatory support for adequate quality of pulsatility and enhanced hemodynamic energy generation in an in vivo animal model. The secondary aim was to assess end-organ protection during nonpulsatile versus synchronized pulsatile flow mode. Ten adult swine were randomly divided into a nonpulsatile group (NP, n=5) and pulsatile group (P, n=5), and placed on ECLS for 24h using an i-cor system consisting of an i-cor diagonal pump, an iLA membrane ventilator, an 18Fr femoral arterial cannula and a 23/25 Fr femoral venous cannula. Trials were conducted at a flow rate of 2.5L/min using nonpulsatile or pulsatile mode (with assist ratio 1:1). Real-time pressure and flow data were recorded using a custom-based data acquisition system. To the best of our knowledge, the oxygenator and circuit pressure drops were the lowest for any available system in both groups. The ECG-synchronized i-cor ECLS system was able to trigger pulsatile flow in the porcine model. After 24-h ECLS, energy equivalent pressure, surplus hemodynamic energy, and total hemodynamic energy at preoxygenator and prearterial cannula sites were significantly higher in the P group than those in the NP group (P<0.05). Urine output was higher in P versus NP (3379± 443mL vs. NP, 2598± 1012mL), and the P group seemed to require less inotropic support, but both did not reach statistical significances (P>0.05). The novel i-cor system performed well in the nonpulsatile and ECG-synchronized pulsatile mode in an adult animal ECLS model. The iLA membrane oxygenator had an extremely lower transmembrane pressure gradient and excellent gas exchange capability. Our findings suggest that ECG-triggered pulsatile ECLS provides superior end-organ protection with improved renal function and systemic vascular tone.