Erythropoietin and Survival Time

In victims of traumatic deaths, one of the questions that is often useful to investigators is how long the victim lived after the traumatic event. Let’s say someone is in an automobile accident or is shot or stabbed and bleeds to death. Did this take 15 minutes or 15 hours? A hormone within the blood might help with this determination.

Erythropoietin (EPO), a hormone produced in the kidneys and liver, regulates red blood cell (RBC) production. In people who are anemic, that is who have a low RBC count, erythropoietin production is revved up so that more RBCs will be produced by the bone marrow. The body has a way of taking care of itself. Erythropoietin is also a performance-enhancing drug in that it increases red blood cell production and therefore increases the capacity of the blood to carry oxygen. The more oxygen the blood carries the longer and more intensely someone can exercise. Distance runners and cyclists have often used erythropoietin to improve their performance in races. It is banned by virtually every competitive organization in the world.

So what does all this have to do with survival time after an injury? It is been found that when someone is bleeding and their blood count is dropping because of this blood loss, the kidneys and the liver began to produce larger amounts of erythropoietin. All they see is that the red blood count is dropping and that the blood pressure is low and their natural response is to increase the production of this hormone.

A group of researchers at the Osaka City University Medical School’s Department of Legal Medicine recently published an article in the journal Forensic Science International in which they looked at the blood levels of EPO in relationship to survival time after major injuries that caused massive bleeding. They found that victims who survived many hours after such injuries showed a rapid increase in EPO in their blood serum over the first six hours after the injury. They concluded that this test might be useful in determining if someone died early within the six-hour window versus dying later.

How would this be useful in a criminal case? Remember the case of Chante Mallard? This 27-year-old woman in Fort Worth, Texas decided to get drunk and stoned and then drive home at around three o’clock in the morning. Unfortunately Mr. Gregory Biggs was walking along the road. She struck him with her car. He flew through the passenger side windshield and was lodged in the shattered window head down in her passenger seat. Ms. Mallard did what anyone would do in that circumstance: she drove home, parked the car in the garage, and did some more drugs, leaving Mr. Biggs to bleed to death.

Mr. Biggs survived the initial impact and only died later because Ms. Mallard failed to do the right thing and call for the medical care that might have saved his life. The evidence for this was that his blood pooled within the door pocket of Ms. Mallard’s car where his hand had come to rest. The fact that blood ran down his arm and collected in this area proved that he was still alive for many hours after the impact. At death, the heart stops, the blood ceases its movement, and bleeding stops.

Had this new EPO test been available and used in this case, it would’ve shown a very elevated level in Mr. Biggs whereas had he died almost immediately from the impact these levels would be very low. In the latter case, Ms. Mallard would be guilty of reckless homicide but the fact that she ignored this man and allowed him to die a slow death added another level of depravity to this situation. This might explain why she was sentenced to 50 years in prison rather than some shorter time.