Oxygen Isn't Magic: Expanding on My Comments in "The retconning of George Floyd"
Once more, with feeling: "That isn't how this works."
Last week I had the incredible honor of helping out one of the best in the crime-explainer business, Radley Balko, with the second in his three-part series “The retconning of George Floyd,” It’s an excellent and thorough piece, debunking the plethora of misdirections (none uttered with enough of the filmmakers’ chests to call them lies) thrown at viewers by The Fall of Minneapolis, a documentary aiming to exonerate Derek Chauvin in public opinion by a thousand unexamined quibbles with the fact pattern.
The murder of George Floyd is one of the things that made me realize this work was necessary, and it was hardly new territory for me. Radley did, however, put a new one on me: the implication in Fall of Minneapolis that what nurse anesthetist Debra Nelson described as a “big mistake”—not connecting the bag-valve mask to an oxygen bottle—may have been the actual culprit in Floyd’s death.
Just the installment of the series I’m quoted in clocks in at the better part of 10,000 words; I’m sure he’d probably have another book on his hands if he reproduced every source’s rendition of “that’s not how that works“ in full. I do think, however, some of what ended up on his cutting room floor is vital to understand not only what happened to George Floyd, but the difference between what you see on TV and the act of violence against death that CPR actually is.
It Was a “Big Mistake”—And Not the Only One
In the segment of The Fall of Minneapolis relevant to our purposes here, Nelson vaguely states that the delayed release of video footage affected the outcome in some unspecified way. When asked about the most troubling finding, she describes how the video reveals that the oxygen tubing connected to the BVM was not connected to an oxygen source, which the documentary smarmily juxtaposes against a news clipping in which the service’s chief describes the paramedics as having “done everything right.”1 She’s not wrong that it’s a deviation from the standard of care. But it didn’t kill George Floyd.
What CPR Is, and Why It Matters
Generally, cardiac arrests fall into three broad categories:
The heart isn’t beating at all
The heart is beating too erratically to effectively pump blood
Something is blocking the heart, or there’s not enough blood to pump anywhere
In either case, the patient is not going to inhale or circulate oxygen, so Nelson is correct that medical personnel need to do it for them via chest compressions and rescue breathing. However, doing these steps alone will do nothing to restart the heart. Oxygen above and beyond what's in ambient air is a huge deal in preserving neurological function until we can get the heart restarted, but the literature doesn’t really show a statistically significant difference over ambient air.
As shown in the image above, restarting the heart takes vastly different paths based on which of the aforementioned problems it’s having. For ventricular fibrillation or pulseless ventricular tachycardia (the heart pumping too erratically), there are a few drugs and, more importantly, using electricity as a “reset button“ (known as defibrillation), to achieve the return of spontaneous circulation (ROSC). Contrary to what you’ve seen on TV, we can’t shock a flatline; for pulseless electrical activity (the heart conducting electricity but not beating) or asystole (no electrical activity), there’s epinephrine, fluids (overfilling the heart to make it pump harder, more or less), and shots in the dark at reversing the cause, like the sodium bicarbonate Floyd received2.
The paramedic who responded to Floyd testified that when they put the monitor on him, he was in asystole. He later converted to pVT and received a shock; this put his chances of survival at about 3%. The amount of oxygen Floyd received would not have improved this.
On CRNAs
Radley included my skepticism of the credentials of a CRNA to discuss street medicine; I’d like to clarify some of them here.
Certified Registered Nurse Anesthetists can be extremely good at their scope; if you enjoy my writing on lethal injection pharmacology, you have my soon-to-be-CRNA sister to thank, at least in part, for ferrying questions to her professors about drugs we both use but understand to vastly different extents. Her LinkedIn profile, however, shows no experience or familiarity with EMS, who practice a far more austere kind of healthcare. If a missed intervention that had no bearing on the outcome really is the most disturbing part of a cardiac arrest, it may be because you’re used to seeing an army of personnel with an alphabet soup of post-nominal certifications wheeling in everything you need. Trying to do the same thing in a moving vehicle with a guy who maybe knows how to use Narcan gives one perspective.
Nor can she claim any special expertise. Although CRNA is a doctoral degree, Nelson isn’t a physician—much less a cardiologist, the branch of medicine that writes the cardiac arrest guidelines; her expertise in the matter comes down to holding the same ACLS card I have (and I’d bet money I’ve put them to work more). The only reason to take her word on what constitutes a serious medical error in cardiac arrest is if you can’t find someone more qualified who’s willing to say what you need, which raises a more salient question than any posed by The Fall of Minneapolis.
A bit of a tangent here: after multiple threats to alert my supervisor of my “anti-police“ views—those views being that cops shouldn’t have killed this or that person—it should be surprising to see a police union president’s wife try to throw us under the bus. It isn’t, but it should be.
Paramedic educator extraordinaire Bob Page claims to have evidence that transcutaneous pacing (an external version of a pacemaker using the same pads as the defibrillator) can improve survival in asystole. I’ve learned a lot from Bob, but until the AHA changes their mind I’ll have to defer to them.