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Nuclear-Powered Cardiac Pacemakers

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Re: Nuclear-Powered Cardiac Pacemakers

#71

Post by R0b0t1 »

hwillis wrote: post #33
mysterydip wrote: post #13

Earlier quoted context omitted.

> allowing for doctors to check in on their patients and replace either the batteries or the pacemakers themselves I cynically read this as "we needed to get more money out of these patients"

You really should not. 60 beats per minute means that in ten years the leads of a pacemaker will be bent *315 million* times. That's an order of magnitude higher than we typically test fatigue resistance, and even if we were that confident about being able to produce flawless materials, there are millions of different enzymes and acids and temperature fluctuations in the body. Any one of those could impact the fatigu…

> EDIT: oh, and heart disease is the #1 cause of death in the US, while heart surgery is one of the most difficult specialties to get in to. They are absolutely never short on patients, lol.

This is still relevant to his concern, but from the other end. They might be making the labor artificially scarce to increase pay.

Re: Nuclear-Powered Cardiac Pacemakers

#72

Post by kristopolous »

konschubert wrote: post #19
mysterydip wrote: post #13

Earlier quoted context omitted.

> allowing for doctors to check in on their patients and replace either the batteries or the pacemakers themselves I cynically read this as "we needed to get more money out of these patients"

I read this as: Most patients don’t survive those 10 years anyways.

I'd rather live an extra 9 years than 0.

We're all going to die and an extra 9 years is not bad.

Re: Nuclear-Powered Cardiac Pacemakers

#73

Post by NoSorryCannot »

ssizn wrote: post #67
kergonath wrote: post #37

Earlier quoted context omitted.

Yeah, tragic. They are no less human than you are. They had no clue what they were doing, like all of us in general. What fraction of the population is aware of the effect of radiation and the toxicity of medical sources? How would they go about assessing the risk in this situation? Uncontrolled contamination can also harm innocent bystanders, in this case children.

I know not to barge into buildings to steal stuff that doesn’t belong to me and that I know nothing about.

That's right, and it's illegal for rich and poor alike. That's how you know it's fair.

Re: Nuclear-Powered Cardiac Pacemakers

#74

Post by joezydeco »

xtracto wrote: post #39
Bakary wrote: post #17

Tragically relevant story to accompany this article: the Goiânia accident. https://en.wikipedia.org/wiki/Goi%C3%A2nia_accident

Ooh, the Cobalt-60 incident in Mexico is also pretty crazy: https://en.wikipedia.org/wiki/Ciudad_Ju%C3%A1rez_cobalt-60_c... There were houses built of contaminated rebar! The story gets crazier the more you read about it.

It was a thing in the US too. My favorite coffee shop in the suburbs of Chicago got a shipment of tables that had contaminated metal from this incident.

https://www.upi.com/Archives/1984/04/02/Radioactive-tables-r...

Re: Nuclear-Powered Cardiac Pacemakers

#75

Post by adrian_b »

klodolph wrote: post #7
drraj32 wrote: post #5

Just got me thinking: What would it take for us to get to a point where there are small, safe nuclear powered "batteries", that can supply enough electricity for a building.

It would take some kind of complete revolution. It’s not happening. These batteries have very poor power density and are very inefficient. The advantages of nuclear-powered batteries are: - They generate power over a long time, decades, - They generate some heat. They don’t generate much power. If you have a building, you would definitely think of a nuclear RTG as a “very shitty battery”, and that’s even if you don’t…

While Pu-238 is an alpha emitter, so it is difficult to capture the decay energy in any other way than by converting heat into electrical energy, for the radioactive isotopes that are beta emitters there is an alternative where the nuclear batteries function in a way very similar to a chemical battery.

The beta decaying substance is connected electrically to one electrode of a capacitor, while the electrons emitted due to the beta decay are able to pass through the insulating layer of the capacitor, reaching the other electrode.

Thus the capacitor is charged directly by the beta-decay and it can provide electrical energy to the external circuit.

Re: Nuclear-Powered Cardiac Pacemakers

#76

Post by furyofantares »

hwillis wrote: post #33
mysterydip wrote: post #13

Earlier quoted context omitted.

> allowing for doctors to check in on their patients and replace either the batteries or the pacemakers themselves I cynically read this as "we needed to get more money out of these patients"

You really should not. 60 beats per minute means that in ten years the leads of a pacemaker will be bent *315 million* times. That's an order of magnitude higher than we typically test fatigue resistance, and even if we were that confident about being able to produce flawless materials, there are millions of different enzymes and acids and temperature fluctuations in the body. Any one of those could impact the fatigu…

It's a weird argument, though, that we should be checking in on the state of the patient & these devices, but we don't do it unless we have the additional problem of needing to replace a battery.

Re: Nuclear-Powered Cardiac Pacemakers

#77

Post by marcosdumay »

saalweachter wrote: post #65
Bakary wrote: post #17

Tragically relevant story to accompany this article: the Goiânia accident. https://en.wikipedia.org/wiki/Goi%C3%A2nia_accident

It's the scary goldilocks of nuclear waste. On the one extreme, you have the Elephant Foot at Chernobyl, which even today will kill you if you, like, go up and lick it. But it's not going to sneak up behind you, so just don't go over there. On the other extreme you have the release of radioactive water from Fukushima, which instantly dilutes to nothing in the vastness of the ocean. Meh. In the middle, you have radiat…

> and never know it.

Nah... You will know it quite soon.

Re: Nuclear-Powered Cardiac Pacemakers

#79

Post by krisoft »

qbasic_forever wrote: post #10
drraj32 wrote: post #5

Just got me thinking: What would it take for us to get to a point where there are small, safe nuclear powered "batteries", that can supply enough electricity for a building.

RTGs have been around since the 50's and 60's: https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge... For example Russia used them to power lighthouses in super remote parts of their coast. Space probes, mars rovers, etc. use them too.

Absolutely. And not without incidents: https://en.wikipedia.org/wiki/Lia_radiological_accident

Short summary: Soviet engineers installed RTG powered radio relays to support the construction of a damn in Georgia. Political instability lead to the abandonment of the RTGs. Someone scavenged the generators and removed the radioactive cores from them.

Two of the radioactive sources were discovered by men gathering firewood in the forest. They decided to bring them to their camp(!) and cozy up to them to keep warm during the night(!!). Despite showing symptoms of radiation poisoning they kept the cores on their person while loading their truck(!!!). They all suffered terrible radiation injuries.

There are more sources "lost" from the same batch which remains unaccounted for to this day.

Re: Nuclear-Powered Cardiac Pacemakers

#80

Post by leeoniya »

toss1 wrote: post #43
mysterydip wrote: post #13

Earlier quoted context omitted.

> allowing for doctors to check in on their patients and replace either the batteries or the pacemakers themselves I cynically read this as "we needed to get more money out of these patients"

A friend had one of these units that extended his life for over a decade. He had it upgraded at least once, and the programing updated several times, and noted improvements each time (although he never got the one feature he really wanted [0]). So active maintenance is definitely not spurious or mercenary but is genuinely useful. [0] When the pacemaker detected a problematic arrhythmia it would give a couple of defib…

> He wanted a feature where it would tingle or beep or something just a few seconds ahead of time so he could mentally prepare; apparently the second one that was expected was a lot less traumatic.

reminds me of the pre-safe sound prior to collision

https://www.mercedesbenzofnatick.com/new-features-mercedes-b...

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