Dexcom one + calibration help please

[Loobyloo]

I am trialling Dexcom one + sensors as have found Libre to be very innaccurate for me. I have fitted it fine and have my first reading which is 0.7 less than a finger prick which is promising as was finding Libre 1.7 - 4 mmols out. I have seen there is a calibration option and can someone kindly explain at what point and how often i enter finger prick readings? I am assuming not to do on first evening of wearing as may need a settling in time.

 

[goodybags]

I am trialling Dexcom one + sensors as have found Libre to be very innaccurate for me. I have fitted it fine and have my first reading which is 0.7 less than a finger prick which is promising as was finding Libre 1.7 - 4 mmols out. I have seen there is a calibration option and can someone kindly explain at what point and how often i enter finger prick readings? I am assuming not to do on first evening of wearing as may need a settling in time.

I’m sure Dexcom don’t recommend any re-calibration within its first 24 hrs
always remember your not going to get the same reading on a CGM as a BGM for reasons including accuracy of both items
also one is getting its reading obviously from your drop of blood
and the other from your interstitial fluids

 

[Loobyloo]

I’m sure Dexcom don’t recommend any re-calibration within its first 24 hrs
always remember your not going to get the same reading on a CGM as a BGM for reasons including accuracy of both items
also one is getting its reading obviously from your drop of blood
and the other from your interstitial fluids

Yes i understand neither are 100% accurate but not having calibration on Libre i just wondered when i should do and how many times to get to work as it should. Is it an ongoing thing i do once in a while or just for first few days. I won't do today like you mentioned i did think maybe best leave for first day.

 

[goodybags]

Yes i understand neither are 100% accurate but not having calibration on Libre i just wondered when i should do and how many times to get to work as it should. Is it an ongoing thing i do once in a while or just for first few days. I won't do today like you mentioned i did think maybe best leave for first day.

I currently use the Libra myself but have previously as you are currently
trialed the DexcomOne+
here’s what Dexcom say regarding calibration (maybe if I’ve copied & posted correctly)

What is optional calibration? | Dexcom

Calibrating your Dexcom ONE+ is optional.

www.dexcom.com

 

[Loobyloo]

I currently use the Libra myself but have previously as you are currently
trialed the DexcomOne+
here’s what Dexcom say regarding calibration (maybe if I’ve copied & posted correctly)

What is optional calibration? | Dexcom

Calibrating your Dexcom ONE+ is optional.

www.dexcom.com

Thanks for the link Goodybags. It doesn't say when or how often i should do so perhaps i will just do when stable a few times over first few days and hope thats ok.

 

[Proud to be erratic]

I have the Dexcom G7, so my experience could be a little different.

I find that once my sensor has settled in, it often doesn't need any calibration. But just sometimes it can be a bit adrift (>1 mmol/L). Embarking on calibration needs considerable stability, ie no bolus insulin on board, and no recent meals nor recent energetic exercise or activity. If this fundamental stability is not in place, then the natural lag between your own BG and your interstitial levels can wholly confuse things; the perception you might get that the 2 readings are comparable can actually be misleading.

Once you've made the decision that you have steady readings for at least 30 minutes and there is a significant constant differential, do the calibration AND THEN keep your nerve - leave it alone for several hours. Let the sensor not only have time to make its change, but further time to settle with its calibrated position.

I've read comments that some folk need to make iterative or incremental calibrations. I've not needed to do this with my G7. Once calibrated and given time to settle I find the process very satisfactory from one calibration. The calibration seems to be happening within the sensor itself, not from an algorithm from the app. I'm lucky enough to have a Receiver as well as a smart android phone. Calibration from my phone is reflected in readings from my Receiver.

 

[Taighnamona]

I am trialling Dexcom one + sensors as have found Libre to be very innaccurate for me. I have fitted it fine and have my first reading which is 0.7 less than a finger prick which is promising as was finding Libre 1.7 - 4 mmols out. I have seen there is a calibration option and can someone kindly explain at what point and how often i enter finger prick readings? I am assuming not to do on first evening of wearing as may need a settling in time.

I tried Libre 2 way back and found it inaccurate too although I’ve heard the Libre plus is better.
I have self funded the Dexcom 1+ for over 6 months and find it to be very accurate overall. Don’t calibrate in the first 24 hours as it can take time to settle.
If it’s less than 1mmol difference I tend to leave it and just add a note highlighting the discrepancy. If it’s more than 1mmol difference then I would calibrate.
In over 6 months of using I’ve only calibrated a few times as I find it to be very accurate. I use a T2 monitor.
EDIT. I should add that I finger prick test twice a day or more if I’m going to be driving.

 

[Loobyloo]

I have the Dexcom G7, so my experience could be a little different.

I find that once my sensor has settled in, it often doesn't need any calibration. But just sometimes it can be a bit adrift (>1 mmol/L). Embarking on calibration needs considerable stability, ie no bolus insulin on board, and no recent meals nor recent energetic exercise or activity. If this fundamental stability is not in place, then the natural lag between your own BG and your interstitial levels can wholly confuse things; the perception you might get that the 2 readings are comparable can actually be misleading.

Once you've made the decision that you have steady readings for at least 30 minutes and there is a significant constant differential, do the calibration AND THEN keep your nerve - leave it alone for several hours. Let the sensor not only have time to make its change, but further time to settle with its calibrated position.

I've read comments that some folk need to make iterative or incremental calibrations. I've not needed to do this with my G7. Once calibrated and given time to settle I find the process very satisfactory from one calibration. The calibration seems to be happening within the sensor itself, not from an algorithm from the app. I'm lucky enough to have a Receiver as well as a smart android phone. Calibration from my phone is reflected in readings from my Receiver.

Thanks

I have the Dexcom G7, so my experience could be a little different.

I find that once my sensor has settled in, it often doesn't need any calibration. But just sometimes it can be a bit adrift (>1 mmol/L). Embarking on calibration needs considerable stability, ie no bolus insulin on board, and no recent meals nor recent energetic exercise or activity. If this fundamental stability is not in place, then the natural lag between your own BG and your interstitial levels can wholly confuse things; the perception you might get that the 2 readings are comparable can actually be misleading.

Once you've made the decision that you have steady readings for at least 30 minutes and there is a significant constant differential, do the calibration AND THEN keep your nerve - leave it alone for several hours. Let the sensor not only have time to make its change, but further time to settle with its calibrated position.

I've read comments that some folk need to make iterative or incremental calibrations. I've not needed to do this with my G7. Once calibrated and given time to settle I find the process very satisfactory from one calibration. The calibration seems to be happening within the sensor itself, not from an algorithm from the app. I'm lucky enough to have a Receiver as well as a smart android phone. Calibration from my phone is reflected in readings from my Receiver.

Well i am so far very pleased with the accuracy of this compared to Libre 2 and 2 plus which were just so far out i couldnt trust them at all. I thjink like others have said some bodies just don't get on with them. I gave it a good try in case bad batch but after 5 being pretty much the same i have tried the Dexcom one + and fingers crossed seems fine.

 

[Loobyloo]

The only problem so far is the green sticky plaster that surrounds the sensor is rubbish and fell off in bed and found hubby had on his cheek when he woke lol. Couldnt find any specifically for the one + on Amazon. Didn't know if have to let the top cover exposed to air or could cover.

 

[Inka]

You could try below for a patch or underpatch @Looby They have lots:

https://www.typeonestyle.com/collections/bestselling-patches

.

 

[everydayupsanddowns]

I used Hypafix over the top of my Dexcom G6 sensors (which I think are the same size as Dex One). Looks like One Plus follows the size of Dex G7?

A roll of hypafix was a vary cost-effective and soft way of getting G6’s through their restart 10 days when I was self funding. It’s not exactly subtle though.

Opsite Flexifix is transparent and very thin. That might work? You’d just need to cut whatever shape / size you wanted from the roll 🙂

 

[Loobyloo]

I used Hypafix over the top of my Dexcom G6 sensors (which I think are the same size as Dex One). Looks like One Plus follows the size of Dex G7?

A roll of hypafix was a vary cost-effective and soft way of getting G6’s through their restart 10 days when I was self funding. It’s not exactly subtle though.

Opsite Flexifix is transparent and very thin. That might work? You’d just need to cut whatever shape / size you wanted from the roll 🙂

Thanks for that cost effective answer. Some of the stickers are a crazy price. Did you need to cut a hole to expose the sensor or just stuck the plaster over it?

 

[everydayupsanddowns]

Thanks for that cost effective answer. Some of the stickers are a crazy price. Did you need to cut a hole to expose the sensor or just stuck the plaster over it?

Unlike Libre (which has a hole to allow the skin to breathe) my Dex G6 (and Guardian G3 before that) were solid, so I’d just slap a square over the top!

 

[PerSpinasAdAstra]

The One+ is very similar to a G7 - it's the same sensor with the pump integration functionality removed/disabled and without the 'prediction' function the G7 app has. By the way and just to be sure there's no confusion, the sticky patch that comes with it isn't green - it has two layers of plastic, top and bottom, and the top layer of plastic is green. With that peeled off, after the patch has been applied, the patch is white. It's not great though definitely - the adhesive Abbott uses with the Libres appears to be much better than the Dexcom adhesive.

You can calibrate in the first 24 hours if you wish but the readings can be so variable that it's hard to achieve and doesn't provide much benefit. I'd only bother calibrating in the first 24 hours if the readings were very far off the mark. If readings are very far off it may be necessary to calibrate incrementally - as in doing repeated calibration attempts. The sensor doesn't seem to fully accept very big corrections. I read a recommendation somewhere that if the needed correction is bigger than 1 mmol/L then calibrate up or down by 1, wait 25 minutes then calibrate again to the level you want.

Calibration will only result in accurate readings if levels are very stable when it's attempted, which for a non insulin user is typically best done just before meals. The meter you use also matters - some meters are much better than others. I've experimented with three One+ sensors so far and wore a Libre 2 at the same time. I've been using xDrip+, a 3rd party CGM app, with the One+ sensors. In that app it's possible to record finger stick readings and the app places a dot on the graph for that type of reading, but it places it with a 10 minute offset - i.e. it places the finger stick reading as a dot on the graph 10 minutes into the future. This is to help account for the lag time between changes in blood glucose and glucose in interstitial fluid. This enables a person to test and observe the accuracy of the CGM even when BG levels aren't entirely stable. If the CGM is calibrated well and if BG levels aren't changing too rapidly the CGM graph should almost intersect with the finger stick readings (10 minutes into the future).

I have been amazed at how often this happens when using a Contour Next meter to calibrate and verify. The level of correlation between the One+ and the Next readings, once calibration is done well, is astonishing. Between the three One+ sensors I've used so far I found that calibration can last for several days or for less than one day. It appears to drift over time, so if accuracy is important to you it may be worth checking it once per day.

It makes the Libre 2 look like a toy by comparison, at least for me, as the automatic calibration on the Libre 2 never worked well for me. Using the One+ and after verifying calibration I learned that some meals that I had been avoiding as an every-day thing were actually a lot better for me than the Libre 2 made them appear. It seems for example that the expensive low carb bread I've been eating as toast for breakfast most mornings might not be much better for me than normal whole grain bread. That knowledge is important to me and so I'm delighted that I switched to the One+ and have the facility to calibrate it.

 

[Loobyloo]

The One+ is very similar to a G7 - it's the same sensor with the pump integration functionality removed/disabled and without the 'prediction' function the G7 app has. By the way and just to be sure there's no confusion, the sticky patch that comes with it isn't green - it has two layers of plastic, top and bottom, and the top layer of plastic is green. With that peeled off, after the patch has been applied, the patch is white. It's not great though definitely - the adhesive Abbott uses with the Libres appears to be much better than the Dexcom adhesive.

You can calibrate in the first 24 hours if you wish but the readings can be so variable that it's hard to achieve and doesn't provide much benefit. I'd only bother calibrating in the first 24 hours if the readings were very far off the mark. If readings are very far off it may be necessary to calibrate incrementally - as in doing repeated calibration attempts. The sensor doesn't seem to fully accept very big corrections. I read a recommendation somewhere that if the needed correction is bigger than 1 mmol/L then calibrate up or down by 1, wait 25 minutes then calibrate again to the level you want.

Calibration will only result in accurate readings if levels are very stable when it's attempted, which for a non insulin user is typically best done just before meals. The meter you use also matters - some meters are much better than others. I've experimented with three One+ sensors so far and wore a Libre 2 at the same time. I've been using xDrip+, a 3rd party CGM app, with the One+ sensors. In that app it's possible to record finger stick readings and the app places a dot on the graph for that type of reading, but it places it with a 10 minute offset - i.e. it places the finger stick reading as a dot on the graph 10 minutes into the future. This is to help account for the lag time between changes in blood glucose and glucose in interstitial fluid. This enables a person to test and observe the accuracy of the CGM even when BG levels aren't entirely stable. If the CGM is calibrated well and if BG levels aren't changing too rapidly the CGM graph should almost intersect with the finger stick readings (10 minutes into the future).

I have been amazed at how often this happens when using a Contour Next meter to calibrate and verify. The level of correlation between the One+ and the Next readings, once calibration is done well, is astonishing. Between the three One+ sensors I've used so far I found that calibration can last for several days or for less than one day. It appears to drift over time, so if accuracy is important to you it may be worth checking it once per day.

It makes the Libre 2 look like a toy by comparison, at least for me, as the automatic calibration on the Libre 2 never worked well for me. Using the One+ and after verifying calibration I learned that some meals that I had been avoiding as an every-day thing were actually a lot better for me than the Libre 2 made them appear. It seems for example that the expensive low carb bread I've been eating as toast for breakfast most mornings might not be much better for me than normal whole grain bread. That knowledge is important to me and so I'm delighted that I switched to the One+ and have the facility to calibrate it.

Yes i have had a similar experience to you and find the Dexcom far more accurate than Libre 2 or 2 plus which are up to 4mmol out at times. I just don't think my body likes the Libre (I have tried 4). Dexcom One plus however is almost identical to my finger pricks after calibrating a couple of times on day 2 and 3. No need to calibrate after that.