Yes - right click on the skinned mesh and select input > all inputs. That should give you a list where you can middle mouse drag the blendshape node below the skinnode. If you have done stuff like changed the mesh etc. you might not be able allowed to drag the blend under the skin.
In that case I would surgest that you export/import the skinning. If you don't know allready here how I would do it:
Evaluate nodes >ignore all, return the joints to bindpose, export the skinning (Remember to have nice clean UV'S!), detach skinning, delete history, create the blendshapenode anew, skin again, import the weightmaps you saved and finaly evaluate nodes >evaluate all.
Again if you are not aware of this, remember that the joints you had in the skinning when exporting must also be present with the same names in the new skinning that you import to. (No more no less I think.. but i could very well be wrong there"
Hope you make it work!!