This definition is more strict selleck KPT-330 and difficult to accomplish in comparison with other ROSC definitions used in similar settings, that is, “stable pulse with a systolic arterial pressure > 60 mmHg” [45] or “systolic pressure �� 80 mmHg for at least one minute continuously at any time during the resuscitation effort” [44]. Thus, we consider the VA ECMO-mediated CoPP increase to be responsible for an excellent resuscitability and a considerable hemodynamic stability after early ROSC. These findings are in accordance with myocardial metabolism and recovery as outlined in Figure Figure5.5. After a steep increase during cardiac arrest and the initial phase of ECMO treatments, lactate levels corresponding to global post arrest ischemia reach a peak value followed by a plateau level and then a gradual decline.

Interestingly, the peak and plateau lactate levels are significantly lower in the FF ECMO arm, possibly reflecting better organ perfusion. Lactate data are in accordance with myocardial O2 extraction: a steep increase during untreated cardiac arrest reflecting insufficient coronary perfusion is immediatelly reversed after initiating ECMO. Interestingly, no significant difference was noted in O2 extraction related to ECMO treatment arms. The possible explanation might be that despite detected lower coronary blood flow and perfusion pressure in the FS ECMO arm, low O2 extraction, most probably, reflects a sustained satisfactory O2 supply. This assumption might be supported by the threshold character of both myocardial O2 balance and CoPP, meaning that critically low levels have not been reached.

However, this observation has to be interpreted with caution, because the difference in O2 extraction has been detected to be significant between treatment arms already during the cardiac arrest period despite similar baseline values. In the FS ECMO arm, still sufficient CoPP has been generated during the whole protocol, see Table Table3.3. Such a value is well above the CoPP considered to be accompanied by a high probability of ROSC [43,44].We also designed this experimental study with the intention to evaluate cerebral and coronary reperfusion in terms of appropriate reoxygenation. As shown in Additional file 3 and Table Table2,2, both FF and FS ECMO regimens offered adequate (that is, not unintentionally high) brain and peripheral oxygenations expressed by regional O2 saturations immediatelly after ECMO initiation.

Re-oxygenation on ECMO can be easily controlled when using on-line monitoring of blood gases as in our protocol, thus avoiding the Brefeldin_A possible adverse effects of arterial hyperoxemia on outcome after reperfusion/ROSC [46,47].Study limitationsECMO and IABP have been implanted prior to induction of cardiac arrest, which is not the ?real” clinical scenario model.