Wednesday, April 6, 2016
How fast a person can bleed to death is a very common question among authors and I've done several posts on the topic. About a month ago, I got a comment asking a variation of the question.
It's as follows:
It's hard in medicine to give actual time frames. The best demonstration I ever saw of how fast it took to bleed out was from a physician that drilled a hole into a two liter bottle of pop and then squeezed it mimicking a heartbeat. He said the size of the hole could be equated with an injury to the popliteal artery (which is behind your knee) and that bottle was empty in about two minutes.
Devastating injuries to larger arteries (your aorta for instance) can cause the patient to bleed out (hemorrhage or exsanguinate) in 1-2 minutes. It's fast. For instance, if you rupture your descending aorta in a hospital and they know exactly what is wrong with you, and even have a couple of IV's in place, your chances of survival are still not awesome.
Some general rules:
Arterial bleeding is faster than venous bleeding. This is because the pumping action of the heart causes more brisk blood loss. That being said, all bleeding can lead to death if not controlled. It's probably safe to assume that bleeding from an artery without any intervention could lead to unconsciousness in one to three minutes and death in under five minutes.
Uncontrolled venous bleeding might take upwards of twenty minutes or days. Again, if not controlled in any way. Again, this could be variable. The author has a lot of leeway.
Does a fast heart rate accelerate bleeding? Yes. The faster your heart beats, the more blood spills, particularly from an arterial bleed. This is a double edged sword because your body will compensate by increasing your heartbeat during blood loss to compensate for all those red blood cells on the pavement and not in your body carrying oxygen.
Here are other posts on the topic of blood loss:
Author Beware: Arteries vs. Veins.
Author Beware: Arterial Bleeding vs. Venous Bleeding.
Killing my Arteries: Truth or Die by James Patterson. Can IV drugs be given in an artery?
Pregnant Woman Bleeding to Death.
Pregnant Woman Bleeding after Delivery.
Bleeding to death from gunshot wound to the arm and back? What organs can be hit to bleed but not be lethal?
What other questions do you have about characters bleeding to death?