I agree. Using MicroPython in medical applications is with all due respect worrisome. It's not meant to be for crucial tasks and definitely not optimal at all for MCUs. It's really meant to be for simple, hobby applications. It's too high-level (synonym of inefficient) for MCUs.
C and Assembly are the way to go for these critical applications (that's why NASA & SpaceX use C and assembly in embedded electronics). Reliability, repeatability and fast performance is key.