Most people picture bleeding as something you can see, blood on the ground, soaking through a shirt. But some of the most dangerous bleeding of all makes almost no mess. It happens inside the body, where no bandage can reach it and no tourniquet can stop it.

This episode of First 5 Minutes takes on internal bleeding: the hidden injuries that follow serious car crashes, falls, and hard blows to the chest or abdomen, where a person can look shaken but intact while losing blood fast on the inside. The show draws on the work of Dr. Alexander Eastman, a trauma surgeon and EMS physician who led the Rees-Jones Trauma Center at Parkland Memorial Hospital in Dallas, serves as a reserve lieutenant and Chief Medical Officer with the Dallas Police Department, and contributed to the Hartford Consensus, the national effort behind Stop the Bleed.

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