The murder of George Floyd

Explainer: Doctor’s testimony details Floyd’s heart activity

A man testifies in court.
Dr. Bradford W. Langenfeld testifies in the trial of Derek Chauvin on Monday. He worked at HCMC last year. After resuscitation efforts were unsuccessful, he pronounced George Floyd dead on the evening of May 25, 2020.
Screenshot of Court TV video file

George Floyd had “pulseless electrical activity” and his heart wasn’t beating when he arrived at a Minneapolis hospital, a doctor testified Monday.

Dr. Bradford Langenfeld was on duty at Hennepin County Medical Center the night Floyd was brought in after being restrained by police last May, and testified Monday at the trial of one of the officers.

Here’s what Langenfeld saw and what it means:

What is pulseless electrical activity?

It means that some feeble or disorganized electrical activity can be detected on a heart monitor but it’s not enough to make the heart beat and supply blood and oxygen to the rest of the body.

What else did the doctor see?

Floyd had no pulse when he arrived and was in cardiac arrest, which Langenfeld described as the “sudden cessation of blood flow to all the tissues of the body when the heart stops pumping.” The doctor described looking for possible explanations and theorized that hypoxia, or insufficient oxygen, was one of the top possibilities.

Doctors measured gases in Floyd's blood and saw extremely high carbon dioxide levels, again suggesting lack of sufficient oxygen.

What treatments were given?

Floyd was given some medicines that sometimes can help restore circulation, but that did not help. Defibrillators to shock a heart back into normal rhythm do not work in a situation like Floyd’s. A narcotics antidote such as Narcan also does not help once someone is in cardiac arrest, Langenfeld said.

When did the doctor pronounce him dead?

Floyd had been in cardiac arrest before arriving at the hospital and doctors worked on him for roughly half an hour after his arrival. After his heart activity stopped altogether — “flatlining” Langenfeld called it — the doctor pronounced him dead.

The county medical examiner ruled Floyd's death a homicide and said he died of “cardiopulmonary arrest, complicating law enforcement subdual, restraint, and neck compression.”