Medical experts: Floyd’s speech didn’t mean he could breathe

MINNEAPOLIS — As George Floyd repeatedly pleaded “I can’t breathe” to police officers holding him down on a Minneapolis street corner, some of the officers responded by pointing out he was able to speak. One told Floyd it takes “a lot of oxygen” to talk, while another told angry bystanders that Floyd was “talking, so he can breathe.”

That reaction — seen in police restraint deaths around the country — is dangerously wrong, medical experts say. While it would be right to believe a person who can’t talk also cannot breathe, the reverse is not true – speaking does not imply that someone is getting enough air to survive.

“The ability to speak does not mean the patient is without danger,” said Dr. Mariell Jessup, chief science and medical officer of the American Heart Association.

“To speak, you only have to move air through the upper airways and the vocal cords, a very small amount,” and that does not mean that enough air is getting down into the lungs where it can supply the rest of the body with oxygen, said Dr. Gary Weissman, a lung specialist at the University of Pennsylvania.

The false perception that someone who can speak can also take in enough air is not part of any known police training curriculum or practices, according to experts on police training and use of force.

“I’m not aware of any standard training of police officers that lets them know, ‘Hey, if someone is still able to talk they are not having difficulty breathing, so you can just keep doing what you are doing,’” said Craig Futterman, professor at University of Chicago Law School and an expert on use of force. Floyd, a Black man who was handcuffed, died May 25 after officer Derek Chauvin pressed his knee on Floyd’s neck for nearly 8 minutes.

In a recent article in the medical journal Annals of Internal Medicine, Weissman and others wrote that when air is inhaled, it first fills the upper airway, trachea and bronchi, where speech is generated. The article says this “anatomical dead space” accounts for about one third of the volume of an ordinary breath, and only air that gets beyond this space goes to air sacs in the lungs for gas exchange, which is when oxygen is sent to the bloodstream and carbon dioxide is removed as waste.

The volume of an ordinary breath is about 400 to 600 mL, but normal speech requires about 50 mL of gas per syllable, so saying the words “I can’t breathe” would require 150 mL of gas, the authors wrote.

A person can utter words by exhaling alone, using reserve left over after a normal breath is exhaled. But, the article says, “adequate gas exchange to support life requires inhalation . ... Waiting until a person loses the ability to speak may be too late to prevent catastrophic cardiopulmonary collapse.”