It seems we disagree on 6dos. I think it's a useful concept to anchor on, since you can predict the structure of your domain (social networks, renting) based on the size of the network, and then optimize your routing so you get to a certain node (a nice house to live) quickly. Or even in my case - realising there is a path in the first place.
I hope this translates more clearly into engineering terms. The original audience of this post was non-technical.
Haha, well you're right. The point of writing is to think. I never said it was going to be a scientific theory - and really, life is too complex a landscape to build a falsifiable theory anyways. We can still discuss anecdotes though.
Although I would highlight - there is additional high risk now if the sensor becomes faulty, in which case, more insulin could be delivered for incorrect levels while you sleeping, etc.
Insulin pumps (and their cannula; not a "needle") are installed 24/7. They can be "suspended" and the insulin delivery hose unhooked, but they are generally there, and active, at all times. Likewise, a CGM (continuous glucose monitor) will provide, as the name says, continuous monitoring. Both use adhesives to keep them attached and generally remain so, even while sleeping.
Hypoglycemia also may not lead to "waking". After all, a diabetic coma may result from low blood glucose, depending on how quickly it crashes.
Diabetic coma is caused by prolonged hyperglycemia (too much blood sugar) and diabetic ketoacidosis. Many diabetic patients go through months of hyperglycemia and even ketosis before they even know that they have diabetes.
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 can loose consciousness from hypoglycemia, but normally the body will do everything it can, even autophaging your heart muscle proteins to bring it back up. Unless you have been fasting for a really long time, it will just release glucose from glycogen reserves and you recover quickly.
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 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.
Body Area Network! Hahahaha love it, going to use this :)
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.
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
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.
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, ...
[1]: https://news.ycombinator.com/item?id=20606230