Well, unless he was holding his breath or something in Smith and Jones (I can't remember), she saved him with cpr in that too and there might well be further occasions I've forgotten cos I don't bother to remember details like that. :-)

I'm fairly sure she used medical knowledge in The Lazarus Experiment too but I don't remember if that actually saved the day or not. And she tried to revive a redshirt in The Shakespeare Code and Jack in Utopia and... and... she did use her medical knowledge a lot and it's not the character's fault if the writers didn't let it count as a plot resolution. ::shrugs::