1. Get the Diabetes Forum App for your phone - available on iOS and Android.
    Dismiss Notice
  2. Guest, we'd love to know what you think about the forum! Take the Diabetes Forum Survey 2020 »
    Dismiss Notice
  3. Diabetes Forum should not be used in an emergency and does not replace your healthcare professional relationship. Posts can be seen by the public.
    Dismiss Notice
  4. Guest, stay home, stay safe, save the NHS. Stay up to date with information about keeping yourself and people around you safe here and GOV.UK: Coronavirus (COVID-19). Think you have symptoms? NHS 111 service is available here.
    Dismiss Notice
Dismiss Notice
Find support, ask questions and share your experiences. Join the community »

Dexcom CGM

Discussion in 'Insulin Pump Forum' started by GeminiJohn, Aug 24, 2017.

  1. GeminiJohn

    GeminiJohn Type 1 · Member

    Messages:
    16
    Likes Received:
    3
    Trophy Points:
    23
    Hi everyone

    I have a Medtronic 640g insulin pump and recently trialled the CGM sensors that support this pump however after deciding to self fund these sensors on a pay as you use basis....this week I've received an email telling me there's a waiting list of up to 6 months or more due to high demand.
    So I've decided to look into maybe getting the Dexcom instead, I would be interested in any opinions on this like accuracy, smartphone compatibility, price etc??
     
  2. mark4785

    mark4785 Type 1 · Active Member

    Messages:
    33
    Likes Received:
    25
    Trophy Points:
    58
    I use the Medtronic 640g insulin pump and trialled their CGM sensors for a period of about 6 months and to my amazement the CGM had many problems. The main issue was that despite calibrating it as instructed it would only show correct glucose readings 20% of the time. It was a horrendous product and I strongly suspect you will experience the same issue with the Dexcom since this is another product that requires calibration.

    If you are looking for accuracy and smartphone compatibility you should consider the Freestyle Libre. It is not a CGM but its a flash glucose sensor requiring no calibration that you can scan with a device called a Reader as frequently as you like.

    CGM's do not work and I'm surprised they are on the market.
     
  3. paulliljeros

    paulliljeros Other · Well-Known Member

    Messages:
    416
    Likes Received:
    426
    Trophy Points:
    103
    A bit confused why you are suggesting the Dexcom CGM will automatically not be accurate. Have you ever tried it? I find it extremely accurate, but the point of CGM/Flash GM is not so much to get a precise reading at a given time, but to see where your BG has been, and understand where it is heading. Whilst I personally trust my readings each and every day, what I would say is that when I see a reading of, for example 5.2, that in itself is quite meaningless, it is only when you add in the context of what the reading has been doing over the previous 30 minutes, how much IOB and how many carbs have recently been consumed, that you actually see the meaning of the reading.
    As for phones, you should look at the Dexcom G5 for out of the box compatibility, as whilst you can do it with the G4, you would need to invest in some additional tech, such as nightscout and xDrip.
    For anyone in doubt about the benefits of CGM, the book "Sugar Surfing" is well worth a read.
     
    • Like Like x 2
    • Agree Agree x 2
    #3 paulliljeros, Aug 25, 2017 at 8:09 AM
    Last edited: Aug 25, 2017
  4. Deleted Account

    Deleted Account · Guest

    Interesting observation.
    I have trialled both the Libre and the Dexcom G4 and my experience was the complete opposite of yours.
    I wonder if there is something about our bodies/our activities/our diabetes which causes the difference.

    Maybe it is psychological but I was more confident with the Dexcom reading because it was calibrated by me in my body rather than the Libre which is generically calibrated in the factory.

    I guess the lesson is that it is horses for courses - the Libre suits some and a CGM suits others.
    Therefore, if considering either, I would strongly recommend pushing for a trial (I had no trouble organising free trials for both) before investing any money.
     
    • Like Like x 1
  5. mark4785

    mark4785 Type 1 · Active Member

    Messages:
    33
    Likes Received:
    25
    Trophy Points:
    58

    The Dexcom CGM requires multiple blood glucose calibration input like the Medtronic CGM so I see no reason why the Dexcom would be anymore accurate, for me at least. When I say the Medtronic CGM was inaccurate I mean it would indicate a downward trend to silly readings like 3.0 m/mol when multiple physical lancet blood tests showed an upward trend on the other end of the scale. So it was providing inaccurate readings and trends.

    Having switched to the Libre system, it is able to demonstrate accuracy in the readings and trends it provides at all times.
     
  6. donnellysdogs

    donnellysdogs Type 1 · Master

    Messages:
    13,202
    Likes Received:
    12,462
    Trophy Points:
    298
    I got funded medtronic guardian cgm abd its so accuatevto within 0.1 or 0.2?the vast majority of times. I do not calibrate unless my bloods are static though, so this may be a difference.

    They are only able to provide to those that are funded, like you said though. In the interim I would have gone with a libre and waited.
     
  7. ringi

    ringi Type 2 · Well-Known Member

    Messages:
    3,366
    Likes Received:
    1,218
    Trophy Points:
    158
    There will be a lag between the BG level of a finger pick and what a CGM measures, so I can see how only calibrating at times of static BG readings can help.
     
  8. GrantGam

    GrantGam Type 1 · Well-Known Member

    Messages:
    2,607
    Likes Received:
    1,582
    Trophy Points:
    178
    I find it funny that you're negatively reviewing a product that you've never tried...

    Anyway, the calibration feature is actually a benefit, and the Libre's lack of one, is the main reason I migrated to a true CGM. Dexcom G5 in my case.

    Your disproval of all CGM's because of your poor experience with one brand, is a lot like me never buying a red car again because the red one I used to own often broke down...

    For your information, the Libre is not accurate at all times. That much is fact.

    It's a shame you had such a poor experience with the Medtronic CGM, but I'm not surprised. It shouldn't put you off ever trying a Dexcom system though. Believe me, I wouldn't be investing money in garbage. Neither would thousands of other diabetics.
     
    • Like Like x 6
  9. donnellysdogs

    donnellysdogs Type 1 · Master

    Messages:
    13,202
    Likes Received:
    12,462
    Trophy Points:
    298
    Please note with CGMs and Libres you are not advised to calibrate when you have arrows going up or down....

    A libre needs 24hrs to settle... easily done after the first one is in.

    The medtronic cgm is accurate if you dont calibrate whilst you have up n down arrows. Especially if you have had food/correction etc...

    I have huge DP and do not intentionally calibrate when I know I can get rapid changes. Fortunately these are getting fewer, and if need be I do calibrate but normally I would never calibrate with any arrows in any direction.

    CGM's are good nowadays. Years ago I had a freestyle navigator-and boy, that was useless and totally inaccurate. If someone can ouck holes in anything, its me!!

    All CGM's and Libre for blood start up and any callibrations need levels without swings.
     
  10. GeminiJohn

    GeminiJohn Type 1 · Member

    Messages:
    16
    Likes Received:
    3
    Trophy Points:
    23
    Thanks for the replies everyone I'm going to trial the Dexcom G5 as soon as I can....although the accuracy could be a little bit better do people find that the trend arrows are normally true!?
     
  11. paulliljeros

    paulliljeros Other · Well-Known Member

    Messages:
    416
    Likes Received:
    426
    Trophy Points:
    103
    Yes, absolutely ... [for me] the trend arrows are spot on. Don't invest assuming it is a replacement for finger pricks, but it definitely reduces the number required, without a doubt. It also gives your Diabetes team information about your control that you cannot imagine. You are able to give them 1440 BG per day, every day, but that value comes in the trends, more than anything. What I would say, is that for me, taking the average BG over a 3 month period, has always given an accurate (within 0.2 or 0.3) prediction of my HbA1c.
     
    • Like Like x 1
  12. catapillar

    catapillar Type 1 · Well-Known Member

    Messages:
    3,390
    Likes Received:
    2,892
    Trophy Points:
    198
    I have used both Medtronic and dexcom CGMs, but never tried the libre. Personally, I hugely prefer the dexcom: it's easy to insert, it didn't require 24hr warm up (for me), I never experienced a single sensor failure, I only very occasionally saw noticeable accuracy problems and these were usually attributable to an old sensor or fast blood sugar changes, it only needs calibration twice a day. In contrast Medtronic needs the sensor to be in for 24 hrs before transmitter is connected, medtronic wants calibrating multiple times a day yet will only accept a calibration if within 2 of what it thinks you are, I had numerous sensor failures (I have lost count), and had numerous occasions when accuracy was way out.

    So, I don't get on with Medtronic, I find them high maintenance and unreliable. But I think maybe it might just be that my body is not a very good environment for a Medtronic sensor - I can't think of another reason why I get the rate of sensor failures I do.

    On the other hand, I love the Dexcom. I find it easy to use and I'm confident in its accuracy. I'm desperate to go back to it!

    So I think the experience between CGMs can be very very individual and variable, it's probably not sensible to write off all CGMs because of experience with one @mark4785
     
    • Like Like x 2
    • Agree Agree x 1
  13. Tracyann35

    Tracyann35 Type 1 · Well-Known Member

    Messages:
    104
    Likes Received:
    43
    Trophy Points:
    48
    Hi I’m currently on a Accuchek pump which is funded by hospital would you have to fund the Dexcom yourself? Have recently heard good things about this pump!!
     
  14. DunePlodder

    DunePlodder Type 1 · Well-Known Member

    Messages:
    823
    Likes Received:
    613
    Trophy Points:
    153
    This is a very old post.
    Most people do have to self fund Dexcoms.
     
  • Meet the Community

    Find support, connect with others, ask questions and share your experiences with people with diabetes, their carers and family.

    Did you know: 7 out of 10 people improve their understanding of diabetes within 6 months of being a Diabetes Forum member. Get the Diabetes Forum App and stay connected on iOS and Android

    Grab the app!
  • Tweet with us

  • Like us on Facebook