Don' t know if this helps but I hit a deer from a tree stand at 20 yards, the hit was high and passed through under his spine just over the back of the lungs. Decent blood in the snow for 80-100 yards, then nothing. I tracked the deer through the snow by following his tracks (which wasn' t fun as he used trails that had many tracks in it going both directions). On my hands and knees, I came to the deer nose to nose - he was just too week with the loss of blood but was still alive. Would he have died in a few hours? Who knows. Point is, the arrow passed through under the spine and didn' t hit lungs and seemed not to have hit artery (seems like he would have been dead long before I caught up to him if it were an artery).

I' m not sure I buy into that magical spot in the deer that gives them 9 lives or whatever, just bad shots and good shots. Tracking is part of bow hunting though - learn it, love it. Get your deer.