Unohana is like the best healer in SS, she can't die fighting with zaraki... but he shouldn't die too (what would be the point of this training if he is going to die?). I think that there should be at least one good healer from SS (not only some random guys), and since Inoue can't heal everybody (she will probably just focus on ichigo), it would be very smart to save Unohana. But since in this manga no one ever died, we can expect that both of them is going to survive.