6 ms·

On Building My Own Artificial Pancreas

115 points by liamzebedee 7y ago

noir_lord 7y ago
It's a damn shame that years after this became a thing we are still waiting for a proper commercial product to hit the market at a reasonable price, I had a male relative with T1 diabetes and it was a complete burden on his life, We have the technology to improve peoples lives markedly (because we already did) but because of what the author mentioned in the article and the lack of "skin in the game" manufacturers are still dicking about and a lot of this only works because those manufacturers couldn't secure a blowjob in a brothel. $8000 is just insane (yes I know FDA approval, testing all that jazz) but there ~1.3m Americans with Type 1 diabetes alone, there is a massive demand for a cost effective product at scale.
- boogiewoogie 7y ago
  Making a class 3 medical device (really it's a system of devices, infusion + cgm) that works off the shelf versus something that a hobbiest can throw together are two different games.
- dekhn 7y ago
  Making a hardware product that is validated in a regulated market is non trivial. At least part of the cost goes to reducing overall risk to a large market, which open source projects aren't really resourced to address.
  - amelius 7y ago
    Isn't it possible to design the product such that its risks are greatly reduced? E.g. by limiting the amount of insulin it can deliver in a given timeframe?
    - dekhn 7y ago
      This comment falls under the "why don't you just..." cluster. Even implementing a feature like that (assuming it made sense) carries risk (imagine if your limiter's sensor broke and it failed open). Designing reliable systems is incredibly hard. It requires a ton of resources (money, lawyers, engineers) And experience and long time frames with relentless effort to document everything so that when somebody does die, you can root cause it and fix the problem without regressions. I've been continuously impressed with what open source hackers have done with open biology projects, but that doesn't mean any of these products are reasonable replacements for the products that are used by tens to hundreds of millions of people.
      - piersadrian 7y ago
        Agreed - open body-hacking projects are amazing feats of community and perseverance, but the systemic cost and access issues that plague high-end medicine will persist until they’re addressed systemically.
      - jacquesm 7y ago
        > This comment falls under the "why don't you just..." cluster. It does, but just this once it is spot on, the best pumps on the market do just that.
        dekhn 7y ago
        yes, it's spot on, but only a tiny part of a much larger system. And even implementing that feature is devishly complicated. Hence my statement "why don't you just".
    - liamzebedee 7y ago
      A bit of elaboration on the risks you could encounter here: - CGM sensors can be faulty, depending on the rate of change of glucose (they’re actually not measuring blood directly, but interstitial fluids, which are generally lagging by about 15mins and can be inaccurate with large swings) - battery dying out isn’t so bad, since the pump will just default back to its previous basal delivery settings - there are safety maximums on insulin delivery, which prevent among other things, your typical overflow/precision errors - maximums over time though is a more complex issue, something I haven’t yet dug into
      - jacquesm 7y ago
        And then there are... pump actuator failure, syringe seal failure (on syringe based pumps), valve failure (on valve based pumps), user error (on all systems), reservoir running out, occlusion, air bubbles and a thousand other things that can go wrong. This is not exactly easy material in the best of cases and most sensor packages do not have redundancy and will at best address only a small fraction of all possible failure modes.
        sgift 7y ago
        Delivering something fast, accurate and under wildly changing conditions in the human body is far more complicated than most people assume. I still remember when I had to be hooked up to an infusion pump for many hours at a time. In theory this was all pretty simple - I had a port (a permanent link to my blood system), the machine was hooked to the port, the machine was configured to deliver x ml per hour. Easy, right? Well ... moving my arm had a non-zero chance to trigger the alarm (alarm means "the machine has a problem to deliver the configured amount", please do something), moving in the bed had a higher chance, walking over the hospital corridor I could almost guarantee that at some point in a single walk (i.e. one length of the corridor) it would freak out and again start the alarm. And that's for a far easier system in very easy conditions. An insulin pump has to change what it delivers all the time and it has to work always. Sport, work, driving, running, ...
    - vineyardmike 7y ago
      Adding to what others said, too little insulin can be dangerous, so if users don't know/notice that it stopped delivering more insulin, they might not manually add the requisite amounts. Forgetting to take medication is dangerous, overdosing medication is dangerous. It is just not that easy to design a system like this.
- bsder 7y ago
  > It's a damn shame that years after this became a thing we are still waiting for a proper commercial product to hit the market at a reasonable price How many people is the device allowed to kill when it fails? Who pays the bill when that happens? The answer to those questions defines the price and availability of a medical device.
  - noir_lord 7y ago
    Except that you forgot profit. Also once the device is built and certified subsequent devices are at the cost of materials, support and production (and some profit) ... which I suspect is a bit a bit less than 8000.
- DoreenMichele 7y ago
  Someone who can and will build their own is very committed to understanding a great many things. This guy has gone and read what doctors with diabetes have to say because doctors without diabetes are not an adequate source of information for his purposes. To build one you can sell to anyone who has diabetes (and the money or insurance to cover it) you have to do a lot of "idiot proofing." You can't assume they will keep up with all the information, best practices, etc. They want it to just work and that's not what you are seeing with the build-your-own crowd.
- nshepperd 7y ago
  Seems to me this is a principle-agent problem, really. Manufacturers and the FDA are only liable for one part of the system's safety - immediate injury or death attributable directly to a specific error. They're not liable for the gradual systemic damage caused by not using closed loop algorithms (due to worse blood glucose control). Hence hobbyists home brewing this stuff. Only when you're making things for yourself are incentives properly aligned.
- refurb 7y ago
  Spoken like someone with little knowledge of what it takes to get a medical device approved by the FDA. As an FYI, you can’t “move fast and break things” when it comes to medical devices.
  - bayesian_horse 7y ago
    They apparently do, though.
- TrackerFF 7y ago
  One would think that insurance companies would jump through flaming hoops to get their diabetes clients the best possible treatment. It is such an expensive condition (I would guess the most expensive), which just gets worse with time. My sister has T1, and it's a sh!tty disease. She's young, lives a very healthy lifestyle, but still these complications keep creeping up. I (and my sister) are very lucky to live in a country with socialized healthcare, so there's no financial burden on her - but I can only imagine how expensive it would be for those without that option - worst case the uninsured; more so in the long run.
jacquesm 7y ago
So, for those of you that feel that this is worthy of hacking: Diabetes is one of those diseases that seems right where your average hacker would like it to be. A single value (Blood Glucose Level) which you can read using some sensor and an automated delivery method. Connect A to B using some 30 lines of Python and call it a day. But it is not that simple. The manufacturers of these devices have to go through some pretty strict testing regimes in order to ensure the devices work well when produced in quantity. And that is where the trick lies. Doing this once, for yourself with nobody at risk but you if you fuck up and getting away with it is easy. Doing it repeatably for 10's of millions of people with all your risks analyzed and regulators happy is very, very hard.
- phkahler 7y ago
  See Boeing MCAS for an example of how a seemingly simple fix is actually not.
- abtinf 7y ago
  Note that glucose is only a proxy for the actual thing we want to control, which is insulin.
  - DoreenMichele 7y ago
    Insulin controls blood glucose. So how do you figure blood glucose is merely a proxy for insulin and not the actual thing an artificial pancreas is intended to control?
    - Fr0styMatt88 7y ago
      My guess - where does the target blood glucose level come from in a non-diabetic? The thing the body can't produce is insulin. Higher than target blood glucose is a sign that not enough insulin is being produced. I can roughly see the logic there.
      - DoreenMichele 7y ago
chrispeel 7y ago
I'm curious what the build-your-own-pancreas people have to say about Tidepool's plan to build an iOS app to do the control logic, and at the same time developing standard interfaces to insulin pumps and glucose monitors. Any comments? https://www.tidepool.org/blog/tidepool-loop-medtronic-collaboration https://www.tidepool.org/blog/tidepool-loop-medtronic-collab...
- liamzebedee 7y ago
  Yes! I think this is fantastic. Tidepool’s employees actually have worked on many of these open-source projects, are funded a lot by the JDRF (one of the biggest T1 Diabetes NFP’s) ans seem to be the most aligned with diabetic’s interests. Personally I’ve been using their Tidepool software for two years before this and it’s very good. The Tidepool Loop is actually based off of another FLOSS APS called Loop - so it’s likely the efforts will not go to waste. That being said, there’s still possibility that the pump manufacturers have interest to stifle their development - but we’ll see.
- jacquesm 7y ago
  > Any comments? I hope they don't mess up the encryption on the pump commands. Especially with pumps that can deliver high doses that can be really problematic.
  - AdamJacobMuller 7y ago
    Is it possible to have interlocks whereby a pump will refuse to dose more than X ml over Y hours or is a fatal dose for some people in some scenarios less than a therapeutic does for others in other scenarios?
    - friedegg 7y ago
      Yes, dosages vary by your size, weight, gender, stress, and other factors. Part of type 2 diabetes is often insulin resistance, but people with type 1 can also suffer from it as well (although it's not the cause of type 1). Some people even need to use highly concentrated forms of insulin, ie U-500 instead of the standard U-100.
mirimir 7y ago
This is absolutely amazing! One thing that's unclear, and perhaps I didn't read carefully enough, is how you're connected to this system. Do you wear it? Or are you only connected while sitting, sleeping, etc?
- friedegg 7y ago
  Most insulin pumps are worn 24/7 or very close to it (some people will disconnect briefly when showering, plus switching out tubing/etc). Insulin pumps often use a faster acting type of insulin, so that within 3-4 hours, it's all gone, and from there, you quickly enter diabetic ketoacidosis. You can take it off for short periods of time if you make sure to dose for it or take shots periodically while you're disconnected.
- cypherpunks01 7y ago
  Read the man page! ;) https://openaps.readthedocs.io/en/latest/docs/Gear%20Up/pump.html https://openaps.readthedocs.io/en/latest/docs/Gear%20Up/pump...
  - mirimir 7y ago
    OK, I guess. But I was looking for something in TFA.
    - liamzebedee 7y ago
      Hey Vlad - I added some pictures of what I actually wear day-to-day at the bottom of the post. Hope this helps!
      - mirimir 7y ago
        Thank you! So really that's not much at all. Impressive. So I'm guessing that there's a strap/pouch for the pump, right? Are the CGM and injection port adhesive? And for sure, you're a cyborg now ;) With a body area network (BAN). And with much more stable insulin and glucose levels than you could achieve manually. Very cool.
bobowzki 7y ago
I'm a bit annoyed people keep calling this an artificial pancreas. The pancreas does a lot more than producing insulin.

115 points by liamzebedee 7y ago

It's a damn shame that years after this became a thing we are still waiting for a proper commercial product to hit the market at a reasonable price, I had a male relative with T1 diabetes and it was a complete burden on his life, We have the technology to improve peoples lives markedly (because we already did) but because of what the author mentioned in the article and the lack of "skin in the game" manufacturers are still dicking about and a lot of this only works because those manufacturers couldn't secure a blowjob in a brothel. $8000 is just insane (yes I know FDA approval, testing all that jazz) but there ~1.3m Americans with Type 1 diabetes alone, there is a massive demand for a cost effective product at scale.

boogiewoogie 7y ago
Making a class 3 medical device (really it's a system of devices, infusion + cgm) that works off the shelf versus something that a hobbiest can throw together are two different games.
dekhn 7y ago
Making a hardware product that is validated in a regulated market is non trivial. At least part of the cost goes to reducing overall risk to a large market, which open source projects aren't really resourced to address.
- amelius 7y ago
  Isn't it possible to design the product such that its risks are greatly reduced? E.g. by limiting the amount of insulin it can deliver in a given timeframe?
  - dekhn 7y ago
    This comment falls under the "why don't you just..." cluster. Even implementing a feature like that (assuming it made sense) carries risk (imagine if your limiter's sensor broke and it failed open). Designing reliable systems is incredibly hard. It requires a ton of resources (money, lawyers, engineers) And experience and long time frames with relentless effort to document everything so that when somebody does die, you can root cause it and fix the problem without regressions. I've been continuously impressed with what open source hackers have done with open biology projects, but that doesn't mean any of these products are reasonable replacements for the products that are used by tens to hundreds of millions of people.
    - piersadrian 7y ago
      Agreed - open body-hacking projects are amazing feats of community and perseverance, but the systemic cost and access issues that plague high-end medicine will persist until they’re addressed systemically.
    - jacquesm 7y ago
      > This comment falls under the "why don't you just..." cluster. It does, but just this once it is spot on, the best pumps on the market do just that.
      - dekhn 7y ago
        yes, it's spot on, but only a tiny part of a much larger system. And even implementing that feature is devishly complicated. Hence my statement "why don't you just".
  - liamzebedee 7y ago
    A bit of elaboration on the risks you could encounter here: - CGM sensors can be faulty, depending on the rate of change of glucose (they’re actually not measuring blood directly, but interstitial fluids, which are generally lagging by about 15mins and can be inaccurate with large swings) - battery dying out isn’t so bad, since the pump will just default back to its previous basal delivery settings - there are safety maximums on insulin delivery, which prevent among other things, your typical overflow/precision errors - maximums over time though is a more complex issue, something I haven’t yet dug into
    - jacquesm 7y ago
      And then there are... pump actuator failure, syringe seal failure (on syringe based pumps), valve failure (on valve based pumps), user error (on all systems), reservoir running out, occlusion, air bubbles and a thousand other things that can go wrong. This is not exactly easy material in the best of cases and most sensor packages do not have redundancy and will at best address only a small fraction of all possible failure modes.
      - sgift 7y ago
        Delivering something fast, accurate and under wildly changing conditions in the human body is far more complicated than most people assume. I still remember when I had to be hooked up to an infusion pump for many hours at a time. In theory this was all pretty simple - I had a port (a permanent link to my blood system), the machine was hooked to the port, the machine was configured to deliver x ml per hour. Easy, right? Well ... moving my arm had a non-zero chance to trigger the alarm (alarm means "the machine has a problem to deliver the configured amount", please do something), moving in the bed had a higher chance, walking over the hospital corridor I could almost guarantee that at some point in a single walk (i.e. one length of the corridor) it would freak out and again start the alarm. And that's for a far easier system in very easy conditions. An insulin pump has to change what it delivers all the time and it has to work always. Sport, work, driving, running, ...
  - vineyardmike 7y ago
    Adding to what others said, too little insulin can be dangerous, so if users don't know/notice that it stopped delivering more insulin, they might not manually add the requisite amounts. Forgetting to take medication is dangerous, overdosing medication is dangerous. It is just not that easy to design a system like this.
bsder 7y ago
> It's a damn shame that years after this became a thing we are still waiting for a proper commercial product to hit the market at a reasonable price How many people is the device allowed to kill when it fails? Who pays the bill when that happens? The answer to those questions defines the price and availability of a medical device.
- noir_lord 7y ago
  Except that you forgot profit. Also once the device is built and certified subsequent devices are at the cost of materials, support and production (and some profit) ... which I suspect is a bit a bit less than 8000.
DoreenMichele 7y ago
Someone who can and will build their own is very committed to understanding a great many things. This guy has gone and read what doctors with diabetes have to say because doctors without diabetes are not an adequate source of information for his purposes. To build one you can sell to anyone who has diabetes (and the money or insurance to cover it) you have to do a lot of "idiot proofing." You can't assume they will keep up with all the information, best practices, etc. They want it to just work and that's not what you are seeing with the build-your-own crowd.
nshepperd 7y ago
Seems to me this is a principle-agent problem, really. Manufacturers and the FDA are only liable for one part of the system's safety - immediate injury or death attributable directly to a specific error. They're not liable for the gradual systemic damage caused by not using closed loop algorithms (due to worse blood glucose control). Hence hobbyists home brewing this stuff. Only when you're making things for yourself are incentives properly aligned.
refurb 7y ago
Spoken like someone with little knowledge of what it takes to get a medical device approved by the FDA. As an FYI, you can’t “move fast and break things” when it comes to medical devices.
- bayesian_horse 7y ago
  They apparently do, though.
TrackerFF 7y ago
One would think that insurance companies would jump through flaming hoops to get their diabetes clients the best possible treatment. It is such an expensive condition (I would guess the most expensive), which just gets worse with time. My sister has T1, and it's a sh!tty disease. She's young, lives a very healthy lifestyle, but still these complications keep creeping up. I (and my sister) are very lucky to live in a country with socialized healthcare, so there's no financial burden on her - but I can only imagine how expensive it would be for those without that option - worst case the uninsured; more so in the long run.

jacquesm 7y ago

So, for those of you that feel that this is worthy of hacking: Diabetes is one of those diseases that seems right where your average hacker would like it to be. A single value (Blood Glucose Level) which you can read using some sensor and an automated delivery method. Connect A to B using some 30 lines of Python and call it a day. But it is not that simple. The manufacturers of these devices have to go through some pretty strict testing regimes in order to ensure the devices work well when produced in quantity. And that is where the trick lies. Doing this once, for yourself with nobody at risk but you if you fuck up and getting away with it is easy. Doing it repeatably for 10's of millions of people with all your risks analyzed and regulators happy is very, very hard.

phkahler 7y ago
See Boeing MCAS for an example of how a seemingly simple fix is actually not.
abtinf 7y ago
Note that glucose is only a proxy for the actual thing we want to control, which is insulin.
- DoreenMichele 7y ago
  Insulin controls blood glucose. So how do you figure blood glucose is merely a proxy for insulin and not the actual thing an artificial pancreas is intended to control?
  - Fr0styMatt88 7y ago
    My guess - where does the target blood glucose level come from in a non-diabetic? The thing the body can't produce is insulin. Higher than target blood glucose is a sign that not enough insulin is being produced. I can roughly see the logic there.
    - DoreenMichele 7y ago

chrispeel 7y ago

I'm curious what the build-your-own-pancreas people have to say about Tidepool's plan to build an iOS app to do the control logic, and at the same time developing standard interfaces to insulin pumps and glucose monitors. Any comments? https://www.tidepool.org/blog/tidepool-loop-medtronic-collaboration https://www.tidepool.org/blog/tidepool-loop-medtronic-collab...

liamzebedee 7y ago
Yes! I think this is fantastic. Tidepool’s employees actually have worked on many of these open-source projects, are funded a lot by the JDRF (one of the biggest T1 Diabetes NFP’s) ans seem to be the most aligned with diabetic’s interests. Personally I’ve been using their Tidepool software for two years before this and it’s very good. The Tidepool Loop is actually based off of another FLOSS APS called Loop - so it’s likely the efforts will not go to waste. That being said, there’s still possibility that the pump manufacturers have interest to stifle their development - but we’ll see.
jacquesm 7y ago
> Any comments? I hope they don't mess up the encryption on the pump commands. Especially with pumps that can deliver high doses that can be really problematic.
- AdamJacobMuller 7y ago
  Is it possible to have interlocks whereby a pump will refuse to dose more than X ml over Y hours or is a fatal dose for some people in some scenarios less than a therapeutic does for others in other scenarios?
  - friedegg 7y ago
    Yes, dosages vary by your size, weight, gender, stress, and other factors. Part of type 2 diabetes is often insulin resistance, but people with type 1 can also suffer from it as well (although it's not the cause of type 1). Some people even need to use highly concentrated forms of insulin, ie U-500 instead of the standard U-100.

mirimir 7y ago

This is absolutely amazing! One thing that's unclear, and perhaps I didn't read carefully enough, is how you're connected to this system. Do you wear it? Or are you only connected while sitting, sleeping, etc?

friedegg 7y ago
Most insulin pumps are worn 24/7 or very close to it (some people will disconnect briefly when showering, plus switching out tubing/etc). Insulin pumps often use a faster acting type of insulin, so that within 3-4 hours, it's all gone, and from there, you quickly enter diabetic ketoacidosis. You can take it off for short periods of time if you make sure to dose for it or take shots periodically while you're disconnected.
cypherpunks01 7y ago
Read the man page! ;) https://openaps.readthedocs.io/en/latest/docs/Gear%20Up/pump.html https://openaps.readthedocs.io/en/latest/docs/Gear%20Up/pump...
- mirimir 7y ago
  OK, I guess. But I was looking for something in TFA.
  - liamzebedee 7y ago
    Hey Vlad - I added some pictures of what I actually wear day-to-day at the bottom of the post. Hope this helps!
    - mirimir 7y ago
      Thank you! So really that's not much at all. Impressive. So I'm guessing that there's a strap/pouch for the pump, right? Are the CGM and injection port adhesive? And for sure, you're a cyborg now ;) With a body area network (BAN). And with much more stable insulin and glucose levels than you could achieve manually. Very cool.

bobowzki 7y ago

I'm a bit annoyed people keep calling this an artificial pancreas. The pancreas does a lot more than producing insulin.