The invention relates to a device for treating an individual suffering from cardiac or circulatory arrest or from a stroke, comprising blood withdrawal means (BE) that can be applied to the individual (P), an analysis unit (BA) directly or indirectly connected to the blood withdrawal means for detecting and providing, in the form of a blood analysis result (BAE), at least one characteristic of the blood, directly or indirectly connected to a return means (BR) that can be applied to the individual (P) and is designed to deliver a substance to the individual via the return means (BR).
