"What people die of" seems like the sort of question the medical community should be quite good at answering.

People are waiting for human heart transplants and dying from the wait. I don't think there will be a shortage of patients who we can ethically treat whilst researching this new technique. It certainly isn't binary with a hard "sensitive line".

> "What people die of" seems like the sort of question the medical community should be quite good at answering.

Does it? I'm definitely not a doctor, but it seems like a very difficult question to answer.

Even with perfect information, it seems unlikely there is always a simple/single answer. I would naively expect things like (and I'm making a bit up here, because I'm really not a doctor) "not enough oxygen reached his cells, because his lungs were bad at refreshing the air in them, his heart was bad at pumping blood in circles, his veins and arteries were in bad shape due to diet, and he wasn't moving around much because he had a cold further reducing circulation".

But also, we don't have perfect information. We have this set of measurements we could make without harming the patient, or consuming too much time on really expensive equipment like MRIs. Many of those measurements are no doubt themselves subject to some degree of interpretation error and confounding factors.

Maybe I underestimate our doctors, or overestimate the problem, but it doesn't sound easy to me.

One of Atul Gawande's books (Complications) mentions that amongst deaths where an autopsy is done, the cause of death was misdiagnosed by the doctor about 40% of the time. Quote from book [Page 197, Chapter name : "Final Cut"] ---

"How often do autopsies turn up a major misdiagnosis in the cause of death? I would have guessed this happened rarely, in 1 or 2 percent of cases at most. According to three studies done in 1998 and 1999, however, the figure is about 40 percent."

I think 100 years from now people will look back on our current medicine the same way we view medicine from 100 years ago. There is some impressive progress, but we know less than we think we do and conduct a lot of wasteful and harmful procedures.

It's disturbing to learn how thin the evidence is for a lot of modern medical operations. For example, the recommendations for certain cancer screenings have actually been reduced in recent years after it was found they were causing net harm.

It's a bit startling to realize just how young medical science is. I think it's not unreasonable to compare medicine (and a lot of biology) in the nineteenth century to the state of physics in the sixteenth century.

And certain major areas of medicine that people don't think about that much (outside of the field) such as medical informatics are younger still. This stuff has a huge impact on how medical care is actually delivered, but can be kind of left out of the broader public discussions around medicine due to the focus on the actual literal medicines.

Perhaps autopsies are much more likely if the doctor is unsure of the cause?

You're not overestimating the problem - and it's not an easy one to solve. Cause specific mortality is hard, which is why measures like all-cause and excess mortality are often used. For example, the whole "With vs. From COVID?" question is, in the actual field, not actually a controversy because this is how we've measured all infectious disease deaths basically forever.

This is especially true for severe cases like this, people in the ICU, etc.

If someone is in the ICU for multi-system organ failure, gets an infection, and then dies of multi-system organ failure, did the infection kill them? Was it a contributory cause? The same sort of question arises as in this case.

That's why I'm noticing studies that use "all cause mortality". In other words, some people receive X treatment and a similar control group does not. Then you look at how many died in each group regardless of cause because it's just too difficult (and death is pretty much a binary measure). For example, cholesterol lowering drugs (I don't have a source) seem to have no impact on all-cause-mortality, suggesting a failure in our understanding.

Certain invasive cancer treatments can look a lot more effective than they really are, if all cause mortality isn't measured. It's possible to reduce the risk of a patient dying from the particular cancer they have while also lowering their overall life expectancy, since the procedure itself can be extremely harmful.

I have a slide in a lecture somewhere noting that no one would ever die of a healthcare-associated infection if, when admitted to the hospital, they were put in a room full of ozone or hydrogen peroxide fog and intense UV light, while never being seen by a nurse or doctor.

Dying from lung damage is discounted in that scenario.

Indeed. That's the point of the example. "You will almost certainly die in this room, but you won't die of an infection. So if we just look at infection-related mortality, everything is fine."

> "What people die of" seems like the sort of question the medical community should be quite good at answering.

Yes and no, I think.

Technically my dad died of asphyxia. His cancer had spread to his lungs, he'd gotten pneumonia and was in hospital on oxygen. The doctors were clear he wouldn't be going home in the months he potentially had left. So he asked to be disconnected from the oxygen and he died an hour later.

So did he really die of asphyxia? Was it pneumonia, or the cancer? Clearly they were contributing factors, but in the end it was his decision to stop the oxygen, so as such was it suicide?

To me it doesn't really matter. He's gone and I'm just glad he didn't have to hang on to the bitter end.

They're not. Attribution is difficult.

> "What people die of" seems like the sort of question the medical community should be quite good at answering.

Does it? As far as I know, not only are they happy to admit that they can't do it, efforts to try have mostly ceased. We used to do autopsies.

https://www.todaysgeriatricmedicine.com/archive/SO17p26.shtm...

> In the United States it is estimated that the rate of major errors (eg, incorrect cause of death [CoD], incorrect manner of death) found on death certificates completed at academic institutions is approximately 33% to 40%. Internationally, this rate at some hospitals rises as high as 80%

> A wealth of literature is available highlighting the prevalence of death certificate inaccuracy seen at the national and international levels, as well as multiple studies that indicate lack of training as the root cause in the United States. Despite these noted errors, death certificate data continue to inform research pathways and drive medical practice.

https://americanmind.org/salvo/a-covid-death-the-bureaucracy...

> natural cause of death reports are known to have a 20 percent to 60 percent inaccuracy rate according to the peer-reviewed literature.

> The system isn’t built to allow for investigation. In fact, in the state where I worked, doctors are supposed to provide causes of death within 15 hours of the death

> 30 percent of doctors have reported being instructed by the coroner to put an inaccurate cause of death on purpose so the [coroner's] office won’t need to take the case.

> When I worked as a death certificate clerk, I occasionally would send death certificate worksheets to multiple doctors involved in a patient’s care if we had a rush to bury or cremate. In these situations we needed to cast a wider net to find a rapidly responding doctor to finish the record before final disposition. Many times each physician would report an entirely different cause of death.

Death certificates and cause-of-death attribution mainly exist to satisfy procedural requirements, not because they're supposed to be informative or helpful. Courts need to do cause-of-death attribution. It can't be done. So they solve their problem by the very simple method of pretending they can do it anyway. (Courts take this approach everywhere, not just in death certificates. Drug dogs, accounting errors, expert testimony...)

That was my biggest question too. patients die all the time after receiving a human organ transplant just due to the body being in a poor state and/or rejecting the organ. So it was either that case in which even if he received a human heart the same outcome of him dying would have happened. Or it was the pig heart that was the problem. Hopefully it can be determined which case happened, and I am glad he got to spend a few more months with his family.

I think that "Exactly what has happened since and the precise cause of Mr Bennett's death is not clear." indicates that the reporter is not clear, not the physicians. Other sources like https://www.wbaltv.com/article/man-received-historic-pig-hea... talk about infections and indicate his illnesses and treatment were well understood. Even though the patient was a public figure he has HIPAA rights and the hospital has obligations towards him. I don't doubt much more will come out in subsequent published research.

The chance they don't understand in great, great detail the cause of Mr. Bennett's death is nearly zero. The chance that IRBs aren't equipped to handle the ethics of this decision in the future are also very low.

My uneducated guess:

If he had survived for a long time, we would have known that it worked. He didn't survive, so we didn't learn much.

If we try with enough people who are as critical as him, eventually one could survive and we would know that the procedure works for at least some people.

I believe he surpassed several important “milestones” for a transplant patient so his death doesn’t mean the surgery was unsuccessful by any means. And even if it was a total “failure” of a surgery and the patient died on the table that doesn’t mean the team “didn’t learn much”. Not by a long shot.