At me prison RP, I shotgun-ed what I thought to be all the guards. Then as I crawled through the vent to the gate, I was ambushed by all these guards of which I thought I have killed. So, unfortunately, I died. I also learned a lesson. Never go thinking you shot all the guards. Instead, to be safe, have one of your prisoner "Friends" go into the vent. If they get shot... run!