I was looking at some extracorporeal membrane oxygenation (ECMO) images such as the one below and then I realized that only the two most-right parallel examples in this image (parallel VV, parallel VA) seem redundant. In the other four images it seems to me that if that the machine fails, the patient dies.
That made me think of life support machines in general and the importance of their reliability and availability. The patient is highly likely to die in case of mechanical failure. The same applies to mechanical ventilation and other life support machines. So my question is, are all life support machines always redundant and autonomous? Redundant in the sense that if one machine fails entirely the other takes over or keeps working. Autonomous in the sense that without human intervention they are able to restart or self-correct whatever small failure that occurs.
Some additional but related (sub)questions: Do life support machines self detect mechanical failure and shut-down? Do life support machines have batteries in case of grid power issues? How often do life support machine's fail and how likely is that to happen?