That is whack. Although Saudi is known for being generally bat-shit insane. The authorities already abuse Sharia law and interpret it in whichever way they choose that suits their interests. That said, a fair punishment is agreeable. Their definition of "fair" is a whole new story.
I'd be inclined to agree with the hospitals ethical stance on the situation if it wasn't hypocritical. It's ok to use lethal injections on criminals pending final judgement but it's not ok paralyse criminals pending judgement. The question is really more detailed than that because it depends on the availability of a physician or surgeon willing to perform the necessary procedure.