If you downloaded DKS recently, then I would think it should already be updated. Did you try checking anyway, if Steam isn't set to do so automatically?
I'm not sure what the latest version number is. The PC patch was released Dec 23rd, so I would have thought Steam would have been updated a few days or so after that.
If you do have the second patch, then apparently it doesn't prevent all situations that can cause certain boss type opponents to have over-powered attacks.
