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Nuclear-Powered Cardiac Pacemakers

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Re: Nuclear-Powered Cardiac Pacemakers

#231

Post by sgtnoodle »

animatedb wrote: post #169
alphaoverlord wrote: post #110

Earlier quoted context omitted.

If you have complete AV block, a leadless pacemaker is less good than one with multiple leads, since it allows pacing multiple chambers and maintaining synchrony between A and V.

There are now leadless devices that communicate with each other using RF.

That's neat, although the left channel of my wireless earbuds drop out like 2% of the time!

What I want is a shoulder implanted pacemaker that's significantly smaller, with a quarter of the primary battery capacity, and an inductively charged supercap that can store enough charge to run at least week between charges.

Re: Nuclear-Powered Cardiac Pacemakers

#232

Post by sgtnoodle »

RavZterz wrote: post #198
sgtnoodle wrote: post #177

Earlier quoted context omitted.

I don't think my particular pacemaker has the necessary circuitry to generate more than 5V, in pulses less than a few milliseconds. The voltage doesn't really matter much to the muscle. If you got in you could probably put the leads into single-ended mode (so that there's more current path to cause mayhem) and pace my atrium and ventricles at 210bpm, and effectively give me a seizure. I can't imagine it would kill me…

If they were able to cause the pacemaker to fire when they wanted they could time it during the repolarization, which could possibly cause a fatal arrhythmia even in a heart that doesn't need a pacemaker. It's called R-on-T phenomenon and it's usually caused by malfunctioning pacemakers.

I doubt you could do that through configuration changes alone, simply because of how defensive the firmware would be about that exact scenario. You'd probably have to resort to code exploits on top of simply gaining access. Even then, there's probably a rudimentary interlock at the silicon level.

Re: Nuclear-Powered Cardiac Pacemakers

#233

Post by rmdashrfstar »

mabbo wrote: post #181
ToddWBurgess wrote: post #50

If it is a dead body and it is being cremated you take it out so it doesn't explode in the crematorium. I say this as a former funeral director who had to remove them.

HackerNews truly does pull from a large swatch of interesting people, doesn't it?

An appreciation for hypotheticals?

Re: Nuclear-Powered Cardiac Pacemakers

#234

Post by cfu28 »

mensetmanusman wrote: post #225
zaroth wrote: post #157

Earlier quoted context omitted.

I live near Boston which is known for its medical centers, so this might skew things somewhat, but it seems like every graduate I know is going into medicine of some form (surgery, anesthesia, nursing, surgical tech, hospice, etc. etc.) I heard consistently that residency slots are extremely competitive and a lot of qualified candidates get passed over. The more I learn about the process the more insane it seems. Fro…

We turn away beyond capable people, it’s just that we have decided to drastically reduce the number of doctors per capita by artificially limiting the number of medical schools.

It's not the number of medical schools that is the issue, it's the amount of residency spots available after graduating med school (in the us).

Re: Nuclear-Powered Cardiac Pacemakers

#235

Post by sizzle »

ToddWBurgess wrote: post #50

If it is a dead body and it is being cremated you take it out so it doesn't explode in the crematorium. I say this as a former funeral director who had to remove them.

Got any stories of it exploding or more generally speaking things the common public wouldn’t know about from your experience in this fascinating job.

Re: Nuclear-Powered Cardiac Pacemakers

#236

Post by segfaultbuserr »

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.

Tritium-powered betavoltaic batteries are off-the-shelf products, and have existed for decades. You can buy them today. But they can only supply a current on the microamp scale, only useful for some niche sensor applications... On the upside, these batteries are fairly safe.

Re: Nuclear-Powered Cardiac Pacemakers

#237

Post by eternityforest »

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…

I wish phones had radiation detectors(Aside from camera based ones that aren't accurate and use battery). If 100M people had radiation detection, I'm sure we'd get a few hits every once in a while.

Plus it can probably be done in roughly a headphone jack sized spot.

Re: Nuclear-Powered Cardiac Pacemakers

#238

Post by eternityforest »

hwillis wrote: post #46
darwingr wrote: post #23

Could I use it to power my iPhone? Frankly I’m fed up with the need for charging.

It would take about 50,000 hours (5.7 years) to charge a 10 Wh iPhone. A solar cell on the back of the iphone would take roughly a full sunny day to charge an iPhone, with ~2 watts peak output.

I wonder why solar phones don't exist? Even weak indoor light would eventually charge it.

Maybe it would make people put phones in the sun all the time and wear out batteries with heat.

Re: Nuclear-Powered Cardiac Pacemakers

#240

Post by Perenti »

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…

I have an ICD, and have had to have two lead revisions, once when the lead failed to implant, and the second when it cracked. My resting pulse is 100bpm, and the device overpaces me if I exceed 140bpm (unless having sex, when it kicks in at 220bpm. Is this so I'll die happy?). So in ten years my leads cop at least 500 million bends. Since my device does cardioversion and defibrillation there's no way a wireless implant in the atrium and ventricle will work.

The doctors keep quoting figures of how reliable this tech is, but I've had 3 procedures due to device failure in the last 5 years.

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