You would just aim for the exit you intended for the first time and do it again. My first deer was a spine shot and he dumped where he stood and dragged himself a few feet. I waited maybe 5 min. and climbed down and made a safe circle around him to get the shot I wanted. Turned out he died before while I was fixing to do him in and I didn't need to shoot. Years ago I popped a doe in the neck with a rifle and cut her throat with my knife. Seems to be a stupid thing to do looking back on it but she was suffering too long for me.