I’ve searched for my answer to no avail so I’ll post my question.
Is the inserter I see in the online stuff I’ve browsed reusable like my Medtronic inserter was? Or is each sensor inserted with its own one-time inserter?
It seems so obvious that Dexcom should design a reusable inserter to minimize waste and reduce the volume of stuff you need to pack and carry along if you travel with more than just one sensor. But it doesn’t look that way.
Yes.
Here is a video
If each new sensor is packed in a separate cardboard box rather than having a overwrap like the G6 does, it looks like may be larger to transport in luggage. I’m hoping by the time it gets to Medicare recipients that they use some sort of a pure plastic foil overwrap because that would make the size and similar to a rolled up pair of athletic socks.
From the message Tandem just sent out this week it looks like they won’t have pump integration done until the second half of 2023 so I figure 2024 before I can change over.
Does it seem that pump integration in the second half of 2023 is realistic? I’m waiting too, but sure hate to wait that long.
My engineering career was in communications and control with my last 10 years being a network engineer. I have a prety good idea how the system works “behind the scenes”.
I think that Tandem could make any changes and issue a software update tomorrow if it were up to them. They’ve had access to the G7 for months if not years.
What they haven’t had was an FDA-blessed production line G7 with which they can start the tests that the FDA requires for therapeutic medical equipment testing. That will take as long as it takes and nothing moves slower than a govenment bureaucracy in approving changes made by others. The FDA is restricted, understaffed and underfunded and it shows in the things they are required to ignore, things approved that were later withdrawn and the approved things that had no therapeutic improvements over proven safe previously approved drugs, just higher prices.
Here is a fuller explanation of the tech, and the likely process. It’s long, you could skip to the last 3 paragraphs.
All CGMs use analog sensors. They all have analog to digital converters, do scaling, store a limited amount of readings and when communcating send a requested interval of reading to the remote controller. It is relatively uncomplicated complicated. A “smart” wireless digital house HVAC thermostat has equivalent tech, just a much less expensive and more durable sensor.
Dexcom invested a lot of resources to get the basic tech of its CGM right and approved. All the developments since their first one have been refinements in sensor chemistry, packaging and mechanical engineering for manufacturing. Software is what they understand the least so they’re unlikely to make radical changes unless necessary to it.
Tandem on the other hand has devoted a major part of its effort in continuous software development. They are working at least 3 CGM makers, always looking at impoving their algorithm or licensing another, and could incorporate a new algorithm or whatever is needed to convert a completely different CGMs receiver code. Their only obstacle in offering new pump software - is the FDA.
The way it was described in the email makes me believe that what’s involved is relatively simple and that the difference is in a few settings relative to the Dexcom part of the software. The only number that was mentioned was the calibration code.
I could be wrong, but here’s what I know.
I use a 3rd party monitor app called Xdrip+. It does not communicate at all with my t:slim. XDrip+ gets readings from the CGM and it is compatible with several CGMs. It needs to know the type of sensor to switch between the different ways their transmitters encode information.
XDrip+ doesn’t need to have the G6s correct calibration code or know any corrections I make at the pump, I’ve changed changes sensors and seen the calibration codes displayed by XDrip+ and the t:slim be different, but both still show the same CGM number. I don’t need to enter manual calibrations at XDrip+.
So, the calibration code and manual calibations are sent to the transmitter by the pump/receiver-controller, the firmware of the transmitter uses that to scale the analog voltage from the sensor electrode and changes that to a number. All the pump software needs to do is send the sensor the calibration code, ask for and listen to receive the values.
The claimed increased accuaracy of the G7 would require better scaling of the A to D curve. That requires more correction points which requires the calibration code to have more digits or be a mix of numerals and characters. The former is much simpler to implement in the kind of chip usd by these transmitters.
So I figure that all the software needs to know are the calibration code to make the switch. Unless the G7 uses a significantly different way of encoding information between it and the pump/receiver-controller and has recently changed it, the changes that Tandem has to make should be simple.
I don’t know how the FDA certifies pump software. I’m doubt that they have the internal expertise to understand software, just statistically what it produces and how reliably.
So if I were the FDA, I’d ask for a test lab set up with sample G7 sensors, bathing them in varying glucose solutions and had them displayed on a T:slim x2 and a Dexcom receivers for 90 days. At 1440 readings per sensor per day, 100 sensirs would produce 1.29 million tests., and more than that need to verify that the pump displayed like the Dexcom receiver they’ve already approved and responded, just like it would to the same values for a G6 sensor.
I estimate it would cost Tandem $200,000 to do this test, document and submit it in 100 days. So I think Tandem will have proven software-in-pump within 6 months.
If the FDA monitors the test because of public demand, or other incentives and sees good enough statistics they might approve it early. If the FDA gets resources diverted, or has a lot of higher priority submissions to be processed at the same time, or it will take longer.
After FDA approval, then Medicare and the other insurers get involved.
Pstud123:
This is good stuff! I even mostly understood most of it! I agree with you that T’s work is more software and D’s is equipment, sensors, chemistry, etc.
I’m also curious about your use of a separate third party monitor, but that’s more personal and a separate thread. Perhaps a private conversation btwn us if you’d care to? Your call…
There are a lot of us using xdrip app, installed on our android phones/watches. There are advantages and disadvantages compared to Dexcom app, but the advantages outweigh disadvantages for me, so I’ve been using it for three years, since I started on G6.
You can find lots of info on this forum and elsewhere online, maybe start here:https://forum.tudiabetes.org/t/could-someone-provide-an-easy-explanation-of-xdrip/80816
p.s. as far as I know (I could be wrong) xdrip does not support G7 directly, but only in “companion” mode. This is not an issue for me since I am still using G6. If you are already using G7, then personally I would wait until xdrip supports G7 directly before switching to xdrip.
The new tandem pump, mobi was developed with the G7 in mind so when it hits the scene if it ever gets released, it will already be able to accept the G7 data and use it for control IQ.
I don’t know if it will be backwards compatible to the G6. We will have to see it when it comes out.
I was assured though that it will be already approved at release.
It’s a huge lay out to approve 3 different cgm. I’m pretty sure that the cgm companies are sharing that bill with the pump companies because they both gain a lot from the partnership