• Please Remember: Members are only permitted to share their own experiences. Members are not qualified to give medical advice. Additionally, everyone manages their health differently. Please be respectful of other people's opinions about their own diabetes management.
  • We seem to be having technical difficulties with new user accounts. If you are trying to register please check your Spam or Junk folder for your confirmation email. If you still haven't received a confirmation email, please reach out to our support inbox: support.forum@diabetes.org.uk

How off should my libre be

Status
This thread is now closed. Please contact Anna DUK, Ieva DUK or everydayupsanddowns if you would like it re-opened.
Jo-Jo-T1

Jo-Jo-T1

Member
Relationship to Diabetes
Type 1
My sugar's have been great but I was down my allotment and was feeling low so I grabbed a nescafe sachet had that whilst with my eldest done a sensor reading about hour later and it said 11.6 so I checked on my blood glucose monitor and I was 23.6 is the sensor supposed to be that far out. Sometimes it says I'm 2.0 and BG is 5.7 I'm a bit curious as to any advice this is my first sensor
 
Those examples sound a bit extreme but there are some things to consider
- Libre sensors are less accurate for some people during the first 24 to 48 hours as our bodies get used to having an alien object inserted. I always insert my sensors at least 24 hours before starting it to overcome this.
- Libre is about 15 minutes behind finger prick. This could lead to a significant difference if my blood sugar is rising or falling quickly.
- Libre is most accurate between 4 mmol/l and 8 mmol/l. The further from this range, the least accurate the sensor is. This is most obvious for high numbers so I always try to double check highs with finger pricks before correcting.
- I find my sensors can drift through their life. For this reason, I always do a finger prick check when my blood sugars are stable.
- Libre are "factory calibrated". Unfortunately, some of us seem to have different physiology to the Factory Man. There are alternative, non-official phone apps which use a different algorithm to convert interstitial fluid readings to blood sugar readings. This can include calibration against a finger prick reading. I use xDrip+ on my Android phone. Other apps include Glimp on Android and Spike on Apple.
- Just as sensors may struggle when first inserted, they can also be affected by infections. Some people find their sensors are out when they get itchy.
- Some sensors are inaccurate. Abbot are aware of this and will replace them if you call them. I strongly encourage you to call them even if you get the sensors of prescription - NHS does not have enough spare cash to waste on faulty goods.
 
The sensor always lags when the blood glucose changes rapidly. The sensor measures the glucose in the interstitial fluid, not the blood, so it takes a around 15 minutes to catch up either way. If it persists in situations where you know a rapid change hasn't occurred, ring Abbott and they will send a replacement sensor. They will want to know the serial number of the sensor, which you will find in System Status on your reader.

Later edit: @helli types faster than me!
 
I find that my Libre can be one whole unit out (lower than finger prick result) at low levels (hypo) and may be higher at the other end of the scale although I rarely get the opportunity to do a double check when it is stable at high levels and as others have said, when levels are changing rapidly there will be a time lag difference, so you can really only compare when levels are stable... ie when the graph shows a pretty horizontal line or very gentle slope and the arrow on the Libre is horizontal.

Was there a reason why you didn't scan when you were feeling low rather than an hour later? It really is important to check before you treat as a hyper can sometimes feel like a hypo and adding carbs to an already high BG is not a good idea. The Libre is there to make readings more easy and convenient so it seems odd not to use it at the time.
Also, not quite sure what a Nescafe sachet is but assume it is coffee of some sort and therefore probably not suitable to be treating a hypo which is what it sounds like you were doing.
 
helli said:
Those examples sound a bit extreme but there are some things to consider
- Libre sensors are less accurate for some people during the first 24 to 48 hours as our bodies get used to having an alien object inserted. I always insert my sensors at least 24 hours before starting it to overcome this.
- Libre is about 15 minutes behind finger prick. This could lead to a significant difference if my blood sugar is rising or falling quickly.
- Libre is most accurate between 4 mmol/l and 8 mmol/l. The further from this range, the least accurate the sensor is. This is most obvious for high numbers so I always try to double check highs with finger pricks before correcting.
- I find my sensors can drift through their life. For this reason, I always do a finger prick check when my blood sugars are stable.
- Libre are "factory calibrated". Unfortunately, some of us seem to have different physiology to the Factory Man. There are alternative, non-official phone apps which use a different algorithm to convert interstitial fluid readings to blood sugar readings. This can include calibration against a finger prick reading. I use xDrip+ on my Android phone. Other apps include Glimp on Android and Spike on Apple.
- Just as sensors may struggle when first inserted, they can also be affected by infections. Some people find their sensors are out when they get itchy.
- Some sensors are inaccurate. Abbot are aware of this and will replace them if you call them. I strongly encourage you to call them even if you get the sensors of prescription - NHS does not have enough spare cash to waste on faulty goods.
Click to expand...
Thanks for that very helpful
 
Status
This thread is now closed. Please contact Anna DUK, Ieva DUK or everydayupsanddowns if you would like it re-opened.
Back
Top