I don't think she will she stated pretty clearly that she has no intention to. We've seen her bankai in the past and it doesn't seem to have any offensive capabilities, which is very reflective of her personality so while she may or may not be capable of inflicting major damage to an opponent I don't think she will get involved in any fights. As we've seen in the past she tries to avoid confrontation and battles as much as possible.

Not only that but they are in enemy territory and there are already on a rescue mission, so her purpose is to heal the injured and escape with them as quickly as possible. That being said she won't engage any enemies because she herself might get injured and although Orihime is there they are under the impression that she is there voluntarily so they won't be relying on her.