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3 September, 2012 in Kit & equipment
Continuous glucose monitors have been around for a while now, indeed Iâ€™ve been using oneÂ to improveÂ my controlÂ for the last 5 years. The market has been dominated by three main players, all with very similar devices, at very similar â€“ and for many out of reach – prices. That could be about to change.
I spent a few hours with California based C8 MediSensors last week looking at their new take on CGM, which just like the blood glucose meter, was invented by the father of a diabetic child looking at current treatment and thinking, we can do better than this.Â Rather than measure glucose levels from the inside, using a sensor beneath the skin, their device fires a beam of light through the skin to measure the level of glucose in the interstitial fluid. That’s right, no needles andÂ no blood. Theyâ€™re in the process of gaining CE Mark approval which will allow them to sell their optical CGM device in Europe, hopefully this year.
You wear the device, which is slightly bigger than an insulin pump, and its smaller battery pack next to your skin, attached via a material belt that goes around your waist. You view your BG measurements via an app on your smartphone.
Looking at this from the view of someone who already uses CGM, Iâ€™m excited. I know the benefits (and frustrations) CGM can bring, but I also know that that funding can be very hard to get and the ongoing cost of consumables make it too expensive for many people to consider. The C8 has the potential to change this. Let’s take a closer look…
The facts about C8 MediSensors Optical Glucose Monitor System:
- Accuracy:Â company data shows it to be in the same accuracy range as standard invasive CGM – like any CGM, this is about giving you a better view and context to your glucose levels, not an accurate number at a particular moment you can use to bolus from – you still need blood tests for that.
- Techy stuff:Â the C8 uses Raman Spectography to fire light through your skin and vibrate your molecules. As each molecule has a unique signature, the device can identify the glucose molecules and count them (in all honesty, itâ€™s a bit more complicated than that, but you get the idea, thereâ€™s a full explanation here).
- Cost: this is a major winner. The C8 will retail at US$4,000 (around ÂŁ2,500 at todayâ€™s exchange rate). Thatâ€™s about the same cost as one yearâ€™s supply of CGM sensors based on using one a week. The C8 will be guaranteed for around 2 years (varies according to country) and is expected to last at least 4, with running costs minimal in the tens rather than hundreds or thousands of pounds. That makes CGM, while still not cheap, significantly more affordable. Plus it comes with a 30 day money back guarantee â€“ so you have time to play around with it and if you decide itâ€™s not for you, send it back.
- Availability: hold your horses, this is an investigational device not yet on sale anywhere. CE Mark approval is on the cards for later this year, after which it will launch in Europe. I have no timescales on a US release.
UsingÂ non invasiveÂ CGM:
- No pain: as itâ€™s non-invasive there are no needles or insertion devices. Skin irritation is always a concern when you have something on your skin for long periods of time – but I guess you’d have to try it to see how it works for you.
- Getting started:Â when you strap on the system, it should be up and running in around 15-20mins and need one blood test to calibrate (it basically has to warm up, so if youâ€™re hot itâ€™ll be quicker, but will take a bit longer if youâ€™re cold). The only time it should take longer is the very first time you use the device, when youâ€™ll have a 45-60min warm up. This compares very favourably to around a 2 hour warm up for the invasive models.
- Monitoring the results: the C8 device has no separate monitor, instead it transmits its results to an app on your smart phone. The app currently works on Android phones, with an Apple version planned.
- Alerts: high/low alarms will sound on your phone, not on the device itself â€“ this might help with the perennial CGM problem of the alarms being too quiet â€“ on a phone they should be easier to tailor.Â At the moment there are no rate of change or predictive alerts, but they are a future possibility.
- Battery life: Around 10 hours, with 2 batteries provided as standard. So youâ€™re going to need to recharge daily, compared to weekly at the most for other CGMs. Powering your own laser beam takes a fair amount of power.Â Plus you need to make sure you keep your smartphone fully charged, as thatâ€™s how you view your results.
- Sex appeal: the device and battery are pretty bulky and are worn strapped to the stomach via a material belt. Compared to the tiny Dexcom and Medtronic transmitters, which are just a bit bigger than a 50p piece, itâ€™s a major difference. They are working on improving this for future versions.
- Exercise:Â the laser does like to be snuggled up close to the skin, without too much jigging around. So at the moment C8 recommend you donâ€™t use it while exercising as it might give erratic readings. I think thisâ€™ll be one of those things that users will have to play around with to work out for themselves. On the plus side, it is easy to take the belt off and on and start up time is very fast.
- What about the kids?: at the moment its only been tested for use for those over 18, so although theoretically ideal for kids it isn’t officially approved for them to use.
And of course, who wouldnâ€™t want to be able to say to their friends in the pub â€śDid you know, I have the worldâ€™s smallest Raman spectrometer strapped to my stomach?â€ť.
I think this has the potential to allow many more people to take advantage of using CGM as it reduces the big stumbling block of cost, and removes the issue that some have with painful sensor insertion. As someone who already uses standard CGM, Iâ€™m not tempted to switch at the moment â€“ the battery life and size of the device wouldnâ€™t fit with my life. But if I didnâ€™t already have CGM, Iâ€™d be looking at this with interestÂ when it comes out.
For more info, take a look at a video of the C8 in action.
As youâ€™d expect, I didnâ€™t spend my own hard earned cash to go and see this, C8 lured me to their offices with promises of expenses, nice sandwiches and an interesting product, which they delivered on.
As much as I love, cherish and adore my continuous glucose monitor, I have to say there has never been a piece of diabetes kit so expertly designed to mess with your head. My pen, pump and meter combined have never provoked such a wide range of emotions as my CGM. In one day I can go from ecstasy to blind rage, all provoked by one tiny little machine. Here are just a few of the emotional responses it provokes:
Celebration. You wake up in the morning and the graph looks like youâ€™re dead. Youâ€™ve been a 5 all night, one single flat line right across the screen. You celebrate sheer basal brilliance.
Comfort. Youâ€™re a 3. Youâ€™ve finally admitted that it might be a good idea to acknowledge the low and actually eat something. Thereâ€™s something very comforting about seeing the numbers start to climb again on the screen. It happens very slowly, 3.0, 3.2, 3.3, 3.6 but they give you hope that things are moving in the right direction and that a second bottle of juice would be overkill.
Convenience. Youâ€™re just getting on with your day. A quick glance at the CGM shows that all is well with the world.
Reassurance. Youâ€™re going to sleep, on your own. You can see youâ€™re a 6, you have no insulin on board and youâ€™re holding flat. You know the CGM will alarm if you drop below a 4. Youâ€™re reassured and sleep well.
Irritation. There is little more irritating than having a smug little machine remind you that youâ€™re high, when you know youâ€™re high, youâ€™ve been high for several hours and no amount of insulin is bringing it down. Thereâ€™s no need to go on about it. Thatâ€™s why I like the â€śalert silenceâ€ť setting so much, itâ€™s the CGM equivalent of â€śyes, I know, now shut upâ€ť.
Fury. The machine alarms to tell you youâ€™re 17, when you really werenâ€™t expecting that at all. Youâ€™re torn as to where to direct your fury. First you shout at the CGM because thereâ€™s no way in this world you can be a 17 and it is obviously making stuff up. Useless piece of junk. Then you check on your meter and that says youâ€™re actually 16.5, so to be fair to the useless piece of junk it was pretty spot on. So now you have to admit you were wrong and split your raging fury equally between your useless pancreas, your brain which seems to have lost its ability to play at being a pancreas, and the rest of your body because no doubt thereâ€™s something going on in there that caused the 17 in the first place. Aaargh!
Never has one machine provoked so many emotional responses in so little time. Itâ€™s only because itâ€™s delivering great results that the thing hasnâ€™t been pitched out of the window before now.
10 June, 2011 in Kit & equipment
Iâ€™m a couple of months into life with the new Enlite CGM sensors, so howâ€™s it going? Have my thoughts changed since my first impressions?
Insertion. Genuinely, it has never hurt once when Iâ€™ve inserted an Enlite sensor. The marketing spiel claimed it wouldnâ€™t hurt, but I didnâ€™t actually believe it! Iâ€™ve got the hang of inserting it now and itâ€™s pretty much second nature.
Accuracy. The marketing spiel proclaimed greater accuracy. Is it true? Iâ€™d say possibly. I find them to be less accurate during the first 24 hours than the old sensors which is a pain and doesnâ€™t seem to be improved by calibrating more often. After that first day, I find theyâ€™re the same or better than the old sensors. Theyâ€™re definitely more accurate when it comes to lows and highs.
With my old sensors, if they werenâ€™t accurate I would sometimes use the tried and trusted method of fixing anything technical â€“ turn it off and turn it back on again. For sensors, this means turning the sensor off on the pump, turning it back on again and then doing â€ślink to sensorâ€ť so it thinks itâ€™s a new sensor. That often sorted any issues for me, although I havenâ€™t tried it with the Enlites before the 6 day mark.
Longevity. Theyâ€™re licenced to last 6 days and all of mine so far have made it that far. I got one to 12 days.Â All others have lasted the full 6 days, at which point on half of them Iâ€™ve turned off the sensor, removed the transmitter, recharged it, reattached it to the sensor, turned the sensor back on and done â€ślink to sensorâ€ť. Two hours later it asks for a calibration. When Iâ€™ve restarted after 6 days, for all but one Iâ€™ve found the accuracy has tailed off after about 9 days of use.
Positioning. Where to wear the sensor? I wore my old sensors on my back and stomach and always found the ones on my back to be more accurate. Iâ€™ve tried the Enlite on both, and found there to be no difference in accuracy between the two.
Securing. To tape or not to tape? The Enlite comes with tape attached to secure the transmitter which seems pretty robust, but Iâ€™ve never relied just on that, Iâ€™ve always added some extra tape over the top.
All in all, they’re not life changingly better than what came before, but they seem a bit more accurate and they certainly hurt less to insert. Compared to others I seem to have had a pretty smooth ride with CGM and have had few problems over the last 4 years. That experience has continued with the Enlite. It’s a step in the right direction.