Fig. 1

The ICU in vivo: This conceptual figure shows the physiological and technological requirements of the anticipated future of the ICU, where diagnostic devices and organ-assist devices now situated ex vivo will be transferred in vivo. Such an ICU in vivo will be based on personalized physiological tracking and control of bodily, organ, and cellular functions in a continuous manner. These are based on the four pillars of personalized physiological medicine (shown above) where assessment and (1) control of frailty and fitness, (2) organ function, (3) microcirculatory and cellular function, and (4) integration of information of the patient as a whole into a learning environment to provide feedback control of therapeutic modalities of the critically ill patient [3]. The technological components will have to be achieved to realize this concept of the ICU in vivo