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

In this image from video, witness Dr. Bradford Wankhede Langenfeld, the doctor who pronounced George Floyd dead, testifies as Hennepin County Judge PeterCahill presides Monday, April 5, 2021, in the trial of former Minneapolis police Officer Derek Chauvin at the Hennepin County Courthouse in Minneapolis.  Chauvin is charged in the May 25, 2020 death of George Floyd. (Court TV via AP, Pool)
In this image from video, witness Dr. Bradford Wankhede Langenfeld, the doctor who pronounced George Floyd dead, testifies as Hennepin County Judge PeterCahill presides Monday, April 5, 2021, in the trial of former Minneapolis police Officer Derek Chauvin at the Hennepin County Courthouse in Minneapolis. Chauvin is charged in the May 25, 2020 death of George Floyd. (Court TV via AP, Pool)

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.