SACRAMENTO, Calif. — Buffalo Bills safety Damar Hamlin took a serious hit on the field Jan. 2. He collapsed and was resuscitated twice before he was taken to the hospital in critical condition.
Since then, he's received an outpouring of support from around the world and he was released from the hospital Wednesday, but there are still questions surrounding what happened that day.
Sutter Cardiologist and American Heart Association volunteer Dr. David Roberts says there are a couple possibilities, a type of cardiomyopathy or commotio cordis.
Hypertrophic cardiomyopathy is genetic. The heart muscle thickens and that can cause cardiac arrest but Roberts said an NFL player would go through screening for a condition like this.
Then there's Viral Cardiomyopathy where the heart isn't pumping as it should due to some type of viral infection. There is a long list of possibilities for what virus could cause this.
Lastly, commotio cordis. It's when the heart stops from a shock to the chest. Roberts says this is very rare and that in this case CPR would bring a person back immediately, which isn't what happened with Hamlin.
One thing Roberts says is for sure is using CPR and AED saved Hamlin's life.
"Certainly in this case, where you had trained personnel on the field very quickly, I would expect really good CPR was taking place almost immediately, and so I would be very optimistic in that regard. The fact that they got the heartbeat back tells me there's a really good chance the brain's going to be fine. The defibrillation is also a critical piece of this. AEDs, these automatic defibrillators, really should be in all sports facilities," said Roberts. "In this case there's no question that was available to them."
Roberts says there was also a common misconception around the coma Hamlin was in. He says the hit didn't put Hamlin in a coma. When a person needs CPR for more than five minutes, you have to assume the brain is stunned.
"It may not be permanent brain damage, but if the brain is stunned from the lack of normal blood flow and what's been shown to improve brain function and brain survival is to cool the brain down," said Roberts. "What we always do when someone who's had a prolonged resuscitation and the person is not awake right away, we will always cool the body down and put them in a medically-induced coma. We're going to leave them that way for 24 hours."
Then, it may take a few days for them to wake back up, but the goal is to give the brain a good chance of recovery.
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