Because medical equipment is either operating in a strong interference environment, or used in a more hostile environment, even in hospitals, nuclear magnetic **** vibration in the work of the strong electromagnetic interference, so the chip's anti-interference ability is particularly important.
There is also a higher sensitivity, as amplification of bioelectrical signals, pre-amplification, higher sensitivity is essential, such as electrocardiograms, as well as some similar devices.
And then there's the lower power consumption, even micro-power chips that can have uA-level standby currents, or even less, for use in small, portable medical devices.