There are three things to an "artificial pancreas": glucose sensor,insulin pump, and the control logic. The difference between an artificial pancreas and the "manual" operation is just that the control logic is automated.
You even can't "fuck up" very easily, unless you add other diabetic stupidities on top of a malfunctioning control logic. Two failure conditions: a) Too little (or no) insulin delivered. b) Too much insulin.
The second one is the more dramatic/short term. The insulin pump has a limited supply of insulin. The speed of injection is limited. There are probably additional safeguards in the pump's software around knowing you are not an elephant breaking into a candy shop. And you feel the pump acting. You can pull it out if it behaves strangely.
Too little insulin delivered may be trickier, but you still have to check the glucose levels occasionally, probably multiple times a day.
Patients already use "algorithms" for insulin delivery. But they are comparatively shitty and designed for example to deliver insulin as a bolus after a meal. Continuous administration of insulin over a pump already has a lot of benefits. A continuous monitoring already has benefits.
You wake up from hypoglycemia, long before there is more trouble. And the sensor doesn't post glucose levels for example if it gets detached.
Hypoglycemia also may not lead to "waking". After all, a diabetic coma may result from low blood glucose, depending on how quickly it crashes.
Source: my girlfriend is Type 1.
Hypoglycemia in healthy adults mainly results from not eating and develops rather slowly. It's hard to recognize at first, but it will get a lot more obvious before it gets serious.
Hypoglycemia in diabetic patients is more often caused by too much insulin delivered at mealtime and this happens more quickly. Patients can become unconscious before they notice the problem, but usually they recover even without treatment. The goal of diabetes treatment is to avoid this hypoglycemia, also because the body reacts with increased glycogenesis leading to an overshoot of blood sugar.
There are sometimes suicide attempts with insulin. This rarely succeeds, it can result in brain damage, but mostly the patients wake up sometime later.
At night an insulin pump would not need to deliver that much insulin. There are also very long-acting types of insulin, which may be preferable to the short-term insulin in the pump to achieve the "baseline" during the fasting period. Or not. That's a strategy question, I guess. I had type 2 for a short time, and I used long-term and short-term insulin at meal times, with the finger-pricking type of measurement.
I don't think insulin pumps would carry enough insulin or are able to deliver enough.
My point is that there is a relatively large margin of error for any algorithm or software before serious harm occurs, and that the continuous monitoring and delivery is already superior in achieving good glucose curves, regardless if the control loop is manual or automatic.
I've read that continuous sensors help patients to have fewer incidents of hypoglycemia.
> You wake up from hypoglycemia, long before there is more trouble
And this is one of the main styles of diabetic death - not waking up (diabetic comatose).
> And the sensor doesn't post glucose levels for example if it gets detached.
I was more referring to the circumstance when you're lying on your sensor in a funny way, and it begins reporting incorrect levels.
The diabetic coma thing is the opposite spectrum when the blood sugar is extremely high but the cell metabolism has to run on ketogenic fuel because it gets no glucose. Which leads to ketoacidosis, which can ultimately lead to a coma.
So, Theranos can exist, and if the money that had gone to Holmes and then this indeed would be a solved problem. But it didn't. Note that there are pumps with a closed loop option on the market today, but they are neither convenient nor simple to use. It is work in progress. I fully expect a simple to use closed loop system to be available in quantity somewhere in the next year or two based on recent market research. The time is indeed ripe. The basic tech is there and the pumps have achieved a level of miniaturization and reliability that it is feasible, there are still problems to overcome but those are all within the realm of the possible, do not require unobtanium and enough parties are working on it (competition is fierce) that at least one of them will solve it within that time frame.
It's surprisingly tricky to measure chemical concentrations continuously without replacing the "sensor". Blood and other liquids attack and clog everything.
Without continuous glucose monitoring, you can't do artificial pancreasing.
It has just taken time.
As far as I know, we haven't figured out what that mechanism is. But I'm not diabetic and I'm much less prone to being hypoglycemic than I once was, so my reading on the subject is fairly casual compared to when I did things like wrote a research paper on Functional Hypoglycemia in part for my own edification.
$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.
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.
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.
It does, but just this once it is spot on, the best pumps on the market do just that.
- 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
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, ...
Forgetting to take medication is dangerous, overdosing medication is dangerous. It is just not that easy to design a system like this.
Hence hobbyists home brewing this stuff. Only when you're making things for yourself are incentives properly aligned.
As an FYI, you can’t “move fast and break things” when it comes to medical devices.
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.
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.
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.
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.
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.
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?
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.
The pump is actually just in your pocket usually, with a big cord hanging out ready to catch on things hehe. The CGM/pump sets are adhesive but not as much as you'd want sometimes.