Multi-Center Observational study to assess optimal ECMO settings during the first hours of Extra-Corporeal Cardiopulmonary Resuscitation.

Veno-arterial extracorporeal membrane oxygenation (vaECMO) during
cardiopulmonary resuscitation (ECPR) might improve outcome after cardiac
arrest. Two independent propensity matched observational studies show that
survival with good neurological outcome is more than doubled during ECPR
compared to conventional CPR: (10% vs 23% and 5% vs 23%). Eight observational
studies entered a meta-analysis and showed a benefit ratio of 3.15 for good
neurologic outcome one year after arrest, in favour of ECPR versus conventional
resuscitation. Due to the many observational studies, the European
resuscitation council decided that ECPR could be considered during refractory
cardiac arrest.
However, it is well established that reperfusion injury of the brain
can cause microvascular and endothelial dysfunction, leading to cellular
necrosis and apoptosis. Factors that may play a role are for example the rate
that PaCO2 decreases or PaO2 increases directly after arrest; in children for
example, a PaCO2 difference last pre-ECMO - first post-ECMO > 25 mmHg
significantly predicted for mortality. Furthermore, Kredel et al. demonstrated
in veno-venous ECMO that rapid decrease in PaCO2 resulted in a marked decrease
of cerebral tissue oxygenation.
While performing ECPR, following the European guidelines, it is yet
unknown how to adjust the ECMO settings in order to minimize
ischemia-reperfusion injury of the brain. In this study, we want to elaborate
on the optimal ECMO settings in the first three hours after initiation of ECPR.
In order to develop a reperfusion strategy to minimise ischemia-reperfusion
injury of the brain during ECPR, we plan to perform an international
observational multi-center study to determine relevant factors affecting
neurological outcome after ECPR.

Primary Objective: To prospectively identify parameters correlated with
Cerebral Performance Category (CPC)* * 2 at hospital discharge.

Secondary Objective(s):
- Parameters correlated with a CPC*1 * 2, 6 months after arrest
- Parameters correlated with a GCS>13 at day 28
- Parameters correlated with a GCS > 13 at any time
- Parameters correlated to 28 days Mortality
- Parameters correlated to Hospital survival

This is a multi-centre prospective observational cohort study, for a duration
of 1,5 year and will contain patients receiving ECPR during cardiac arrest.
Patients are followed until 6 months after arrest.

There are minimal burden expected to the patient: theoretical it is possible
that the adhesive sensors cause irritation to the skin. The extra blooddrawings
will be perfomed from existing indwelling cannulas. The patient will not
receive extra punctures for study purposes. In the first hour, 4 bloodgas
analysis will be performed (1.5 ml each), and the subsequent 2 hours one
bloodgas analysis (1.5 ml each) each 30 min. These procedures will not cause
any discomfort to the patients, these blooddrawings will be performed from an
existing indwelling catheter. 6 months after arrest, patients will receive a
telephone call by their attending doctor, asking 7 yes/no questions for
assessing their functional status. NSE and cardiac markers (Trop T, CK, CM-mb)
will be determined from routine blood drawings.