Knowledge gained during Henry Hudson's four voyages significantly expanded on that from previous explorations made in the 16th century by Giovanni da Verrazano of Italy, John Davis of England and Willem Barents of Holland.
You are really asking three questions; Your brain begins to die after 4-6 minutes without oxygenated blood being delivered to it. If your blood is flowing out from a wound that causes a few things to happen...less blood is delivered to organs, therefore less oxygen and eventually you will bleed out and that's it.
Well that's what your tissues do when the shock waves kick them. Then the passage collapses. The high-speed firearm that produced the bullet created a disruption in your brain 10 times its diameter. But you're lucky, relatively speaking. If you were shot in the heart, your blood pressure would quickly drop, but it would take 10 to 15 seconds to lose brain function. In that time you could draw your gun, utter last words, or spend some time thinking about your unfortunate situation.