Identification of cerebral perfusion targets during extracorporeal resuscitation

尽管不断努力优化复苏患者的护理，但平均只有8%的患者在院外复苏后存活并能活着出院。在成功复苏的情况下，这些复苏患者中的大量还表现出持续性的神经功能损害。各种研究已经证明，在常规的心肺复苏过程中，使用胸部按压只能达到脑血流不足的效果。为了改善心脏骤停后的再灌注，近年来体外循环泵系统越来越多地应用于复苏(称为ECPR)。在特定的患者中，ECPR相对于传统复苏的优越性已经被证明。然而，ECPR在很大程度上仍然是一种不确定的治疗方法。虽然有明确的常规复苏建议，但仍然没有关于ECPR的建议或目标标准。由于缺乏治疗建议，在临床实践中经常针对不同的再灌流。复苏引起的神经损伤包括缺血部分和再灌注部分。众所周知，在全脑缺血或心脏骤停后的再灌流期间，即使恢复了具有生理血流的体循环，也可以观察到大脑区域没有显示血流灌注。这种现象被称为无回流现象。到目前为止，这种现象的确切发病机制尚不清楚。在我们的Freiburg猪复苏模型中，我们首次成功地证明了使用高体外流量的体外循环系统(ECC)可以逆转无复流现象。这种无复流现象的可逆性提出了一个问题，即高再灌注流量甚至体外循环的已知副作用对无复流现象的影响程度。我们的模型为研究无复流现象的机制提供了可能，同时也为ECCs在复苏中的临床应用提供了信息。

Despite continuous efforts to optimize the care of resuscitation patients, on average only 8% of all patients survive out-of-hospital resuscitation and can be discharged from the hospital alive. A large number of these resuscitation patients also exhibit persistent neurological functional impairments in the event of successful resuscitation. Various studies have already demonstrated that only insufficient cerebral blood flows are achieved during conventional cardiopulmonary resuscitation using chest compressions. These insufficient flows contribute to the aggravation of reperfusion injury after ischemia.To improve reperfusion after cardiac arrest, extracorporeal pump systems have been increasingly used in resuscitation in recent years (called eCPR).In selected patients, superiority of eCPR compared to conventional resuscitation has already been demonstrated. However, eCPR remains a largely undefined therapeutic approach. While there are clear recommendations for conventional resuscitation, there are still no recommendations or target criteria for eCPR. Due to this lack of therapeutic recommendations, different reperfusion flows are often targeted in clinical practice.The neurological damage resulting from resuscitation consists of an ischemia component as well as a reperfusion component. It is known that during reperfusion after global cerebral ischemia or after cardiac arrest, cerebral areas can be observed that do not show perfusion even despite restoration of a systemic circulation with physiological blood flows. This phenomenon is called the no-reflow phenomenon. To date, the exact pathomechanism of this phenomenon remains unclear. In the past, changes of the to be perfused tissue on the one hand and changes of the perfusing blood on the other hand have been discussed.In our Freiburg porcine resuscitation model, we have now for the first time succeeded in demonstrating a reversibility of the no-reflow phenomenon using an extracorporeal circulation system (ECC) with high extracorporeal flows.This reversibility of the no-reflow phenomenon raises the question of the extent to which a high reperfusion flow or even known side effects of extracorporeal circulation influence the no-reflow phenomenon. This will be investigated in this project.Our model offers the possibility to investigate the mechanism of the no-reflow phenomenon and to collect information for the clinical use of ECCs in resuscitation at the same time.