If you hit both lungs on a deer, they can not last longer than 8-10 seconds. If they run as hard as they can, they can make it between 75-90 yards usually. If they trot or walk, you will see them go down if you can see 50 yards. The lower exit would helps us track and it also keep the blood from puddling around the heart and lungs to help seal off the wounds. They will still die, but will last a few seconds longer. I got a beautiful shot on a deer on video this year and it took both lungs out. It went 25 yards, stopped, flicked its tail and fell over dead. I wish all shots were that quick and humane. I was standing over the deer in less than 5 minutes. What a feeling, I was still shaking.