When you are bleeding you can lose around 2 liters of blood without dying.
However if you do lose 2 liters of blood you're gonna need a blood transfusion to replace the lost blood because without a blood transfusion you can die even when the bleeding has been stopped.
If you're bleeding severely you need to have the blood stopped from bleeding quickly or you can bleed to death.
It's very important to stop the bleeding especially if it's severe bleeding and seconds count so if you can stop your own bleeding you should do so even with a shirt, towel or anything else and get an ambulance on the way.
You will need to get to the emergency room and get stitches.
The good thing about calling an ambulance is that the paramedics are trained to help treat your injuries while you're on your way to the hospital.
Usually when you lose 2 and 1/2 pints of blood you die.
Blood is very important to us and without enough blood carrying oxygen to our brains we can easily die.