CO2 guided cardiopulmonary resuscitation – CPR-CO2

Cardiac arrest is estimated to be the third leading cause of death in the United States with a survival rate around 10%. Cardiopulmonary resuscitation (CPR) refers to the management of cardiac arrest patients. Aside the absolute priority to consider defibrillation to restore spontaneous circulation, CPR combines chest compressions (CC) with thorax insufflation to sustain organ perfusion and oxygenation. CC aim to maintain blood circulation via the so-called thoracic pump effect. In parallel to CC, ventilation is necessary to adequately preserve oxygen saturation and CO2 elimination. However, excessive ventilation may harmfully jeopardize circulation while insufficient ventilation may affect oxygenation and generate CO2 accumulation.

In this context, international guidelines recommend to perform high quality CC to optimize circulation and increase chances of survival. Recommendations concerning ventilation strategy exist; even if evidence regarding optimal ventilation and its monitoring during CPR is relatively weak. Despite the importance of such international recommendations, those guidelines may not be adapted to every type of patient and clinical settings, as one size does not fit all. Thus, monitoring tools allowing real time feedback to the rescuer to perform personalized fine-tuned ventilation and CC may permit to significantly improve CPR quality and outcome.

Here, we propose to use the capnogram, i.e., the analysis of the expired CO2 during CPR, as a surrogate marker of both ventilation and CC quality. Based on a strong physiological rationale, the objectives are to confirm and specify the added value of capnogram on an observational clinical cohort to reflect both ventilation and circulation quality during CPR and develop a capnogram-based ventilatory and circulatory (individually adapted) strategies. This CPR strategy will be developed within a transport ventilator and will allow to adjust ventilation parameters and CC in real time.