Handcuffing George Floyd and pinning him face down to the sidewalk – with Derek Chauvin’s knees pressed against his neck and back – all combined to cut off his oxygen supply which led to his death, a respiratory expert testified Thursday called by the prosecution.
“Floyd died of low oxygen, and it caused damage to his brain which we see and it also caused a PEA arrhythmia which caused his heart to stop,” said Tobin, a specialist in lungs and intensive care at Edward Hines Jr. VA. The hospital’s school of medicine and Loyola University in Chicago, told the court.
In a direct glance at the defense case, Tobin said Floyd’s pre-existing health conditions had nothing to do with his death. The presence of fentanyl also didn’t have a significant impact, Tobin said.
“A healthy person subjected to what Mr. Floyd was subjected to would have died as a result of what he was subjected to,” Tobin said.
Floyd, a 46-year-old black man, died on May 25, 2020, after Chauvin, who is white, pressed a knee to Floyd’s neck and back for about nine minutes as two other officers held him down. Video of the arrest captured by a spectator sparked widespread outrage, sparking protests in the United States and around the world.
Chauvin, 45, former Minneapolis police officer, is on trial for unintentional second degree murder; third degree murder; and second degree manslaughter. Thursday marked the eighth day of the trial.
Expert rejects role of fentanyl
The prosecution claims that Chauvin pressing his knee against Floyd’s neck caused his death. But the defense contends that Chauvin did what his training taught him and that it was a combination of Floyd’s underlying medical conditions, drug use, and the adrenaline circulating in his system that ultimately got him. kill.
Tobin dismissed any suggestion that the fentanyl in Floyd’s system led to his death, saying that his calculations showed Floyd’s respiratory rate before he passed out would have been much lower if that had been the case.
When questioned by prosecutor Jerry Blackwell, Tobin conducted his detailed examination of Floyd’s death, based on medical records, videos and interviews. Tobin explained the actions that led to Floyd’s lack of oxygen and his eventual death: that he was handcuffed, put into a supine position (i.e. face down), and his knees Chauvin were squeezed into Floyd’s neck and back.
“All of these four forces will ultimately result in the low tidal volume, which gives you shallow breaths, ”he said.
Tobin said that the way the police pressed Floyd’s handcuffs, combined with the fact that Floyd was pressed against the hard pavement, was as if his left side was placed in a vise “which totally interferes with the central features of the way. which we breathe. “
“There were virtually very few opportunities for him to be able to get air through the left side of his chest,” he said.
“He’s stuck against the street. And so the street plays a major role in preventing him from expanding his chest.”
‘Examine your own necks’
Tobin also explained that Chavin’s knee on Floyd’s neck “is extremely important because it will obscure (stop) the air coming in through the passage.”
“Officer Chauvin’s left knee is practically around the neck most of the time,” he said.
At this point in his testimony, Tobin urged jurors to “examine your own neck, all of you on the jury right now” to better understand the effect of a knee on a person’s neck. Most jurors felt their necks as Tobin ordered, though the judge later told them they didn’t have to.
Based on videos of the incident, Tobin said he calculated that half of Chauvin’s weight, 91.5 pounds, fell directly onto Floyd’s neck.
Tobin told jurors what happens when the space in the airways narrows. Breathing then becomes “enormously more difficult”, he said, comparing it to “breathing through a straw”.
He said if the hypopharynx – the lower part of the throat – becomes totally blocked, it only takes a few seconds to reduce the oxygen level to where it would cause “either a fit or a heart attack.”
As for Chauvin’s knee squeezed into Floyd’s back, that meant there was “a huge increase in the work Mr. Floyd was doing just to try and cope with what was going on under the neck, leaving out what was going on. was happening above the neck, ”Tobin mentioned.
Tobin also explained that just because Floyd was talking and showing in motion on video doesn’t mean he was breathing properly.
He said a person can keep talking until the airway narrows to 15%, but once it goes below it is dangerous. “To the point where you can’t speak… you’re in big trouble,” he said.
The trial will continue on Thursday.