An emergency medicine doctor who treated George Floyd the night he died testified in court Monday that he believed Floyd had died of “asphyxia,” the common term for oxygen deprivation.

Dr. Bradford Langenfeld made the statement during his testimony in the trial of Derek Chauvin, the former Minneapolis police officer charged with murdering Floyd on May 25, 2020.

Bystander video showed Chauvin, who is white, kneeling on Floyd’s neck as Floyd, who is Black, repeatedly stated that he couldn’t breathe. Chauvin continued to kneel on Floyd’s neck for several minutes even after Floyd become motionless and ceased breathing.

Chauvin was charged with second- and third-degree murder as well as second-degree manslaughter. He has pleaded not guilty to all of the charges.

Langenfeld testified that Floyd was in cardiac arrest and “absolutely” suffering a medical emergency when paramedics brought him into Hennepin County Medical Center the night of his arrest. He said he tried to resuscitate Floyd for roughly 30 minutes before he officially pronounced Floyd dead at 9:25 p.m. CT.

Prosecutor Jerry Blackwell asked Langenfeld if his leading theory for Floyd’s cardiac arrest had been oxygen deprivation. Langenfeld said yes.

“That was one of the more likely possibilities,” Langenfeld testified. “I felt that ― at the time, based on the information I had ― it was more likely than the other possibilities.”

“Asphyxia is a commonly understood term,” he added when asked if there was another name for death by oxygen deficiency.

Chauvin’s attorney, Eric Nelson, has argued that Floyd’s death was caused in part by high blood pressure, heart disease and drug use ― not by Chauvin kneeling on his neck.

During his cross-examination of Langenfeld, Nelson asked the doctor if fentanyl and methamphetamine can cause hypoxia, or a lack of oxygen. Langenfeld said yes.

Earlier Monday, Langenfeld testified that the two paramedics who brought Floyd into the hospital that night ― Derek Smith and Seth Bravinder ― did not report that they believed Floyd had suffered a heart attack or drug overdose. 

Langenfeld said he had considered the possibility that Floyd’s cardiac arrest was caused by “excited delirium” but dismissed that theory since the paramedics did not report Floyd being “very sweaty” or “extremely agitated” ― two common symptoms of the condition.

“The absence of that information was telling in that I didn’t have any reason to believe that that was the case here,” Langenfeld testified.

He said he did not treat Floyd with Narcan ― a medication designed to rapidly reverse opioid overdose ― that night, and said the paramedics didn’t report treating him with Narcan either.