Introduction
The benefits of extracorporeal cardiopulmonary resuscitation (ECPR) remain an area of debate. Furthermore, studies on optimal patient selection and timing of extracorporeal membrane oxygenation (ECMO) application for patients with cardiac arrest are lacking. Nevertheless, ECMO has recently emerged as a major treatment modality for patients with refractory cardiac arrest.1-4 A small number of researches have reported favorable predictors for successful ECPR,5-8 but their results were based on comparisons of variables before and when ECMO was applied.
Post-ECPR care factors, for example, ECMO maintenance, left heart decompression, and hypothermia, are equally important.9, 10 The pulse pressure on arterial waveform after ECMO initiation decreases because preload decreases while the afterload increases.11 Furthermore, post-cardiac arrest myocardial dysfunction affects pulse pressure after ECPR.12 Lack of pulse pressure can lead to left ventricle (LV) dilation, myocardial injury, pulmonary edema, and development of LV thrombosis and systemic embolization. Previous reports suggested that pulsatile ECMO, which may provide physiologic pulsatile pressure, is more beneficial than non-pulsatile ECMO in terms of clinical outcomes.13-15 Sustained pulse pressure after ECPR may better maintain physiologic hemodynamic status like as pulsatile ECMO.
The purpose of this study was to identify predictors associated with successful weaning off ECMO support after ECPR, that involve post-ECPR care as well as pre- and intra-ECPR variables. We hypothesized that some post-ECPR variables would be associated with clinical outcomes.