Shoulder Impalement (Abandoned Area situation)

My Fantasy Novel MC is in thier version of the military, and was with her partner (units of two) looking for a person through an abandoned modern day town. (Think half-finished buildings; rebar exposed and all that.) Explosion happens, knocks them both out, and along with the obvious bumps/bruises/other injuries caused by explosions, MC has been impaled through the shoulder and pinned to one of the surviving walls.

Now, knowing that medical help/evac is at least 10-12 hours away, what could be done to try and lessen the damage? I know that the shoulder has to be stabilized, along with making sure the pole isn't going to start moving and cause more damage. Her partner has basic first aid training, but is otherwise hopeless when it comes to medical treatment, and they have one small medic kit with them. Said kit consists of gauze, bandages, medical tape, gloves, painkillers, and the rest of the emergency gear you'd normally find in a first aid kit for military usage. Yes, I'm still looking into that one, too.