Sensor glucose and blood glucose: What's the difference?
Many of you have been wondering what the difference is between sensor glucose and blood glucose values. To help give you a better understanding, this video demonstrates and explains why the two values will rarely match and are expected to be different. Have questions after watching the video? Let us know in the comments below.
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Occasionally, my BG and SG will differ by 100 points, or more. I understand the roller coaster concept, however, it would be great to have something more dependable to rely on. I still test my blood glucose at least a dozen times a day and my HA1C is 5.4 so guess I'm doing OK.
Hi Rebecca, when glucose levels are rising or falling quickly, there may be a larger difference between your BG and SG meter values, such as after meals or taking a bolus of insulin. You may also find this information helpful: http://www.medtronicdiabetes.com/customer-support/sensors-and-transmitt…. I will have someone from my team connect with you to try and help.
Like Rebecca I too experience differences of more than 100 points between SG & BG. When it happens my SG is the lower # and BG is the higher #. Today my 8 am BG was 224 and SG 124. The trend line overnight was fairly steady but in the 120 range on the graph. I did a calibration. At 11 am my BG was 282 and my SG was 120, again with the trend line fairly steady in the 120 range. I received NO alarms. My sensor is 3.5 days old. I contacted Medtronic to find out why I didn't get an error that the BG & SG were so different. After 45 minutes speaking with Christina, the only thing she could suggest was to change my sensor. When I asked her why I didn't get any alarms, she said the pump isn't setup to give those kind of alarms. Shouldn't I get a calibration error if the BG & SG are more than 100 points different for more than 3 hours? I am beginning to rely on that trend graph for knowing when my BG is going up or down. Am I going to have to go back to testing 6-8 times a day like Rebecca??? If so, then what's the advantage of the sensor?
Hi Debbie. I understand this can be frustrating. We do recommend calibrating 3 to 4 times a day for optimal sensor performance. You may find this information on why sensor readings are different from BG readings helpful: http://www.medtronicdiabetes.com/customer-support/sensors-and-transmitt…. You may also find this article from one of our customer’s initial experience using the system helpful, too: http://www.loop-blog.com/blog/My-Initial-Thoughts-on-the-MiniMed-530G-w…. I will have one of our advanced specialists connect with you to try and help. Please let me know if there’s anything else I can help you with.
This is good information. It makes understanding the values a bit better and why they differ.
Very nicely done and comprehensive. I can't wait to get mine! I am waiting to see if affordable care act will cover the new pump. Especially the sensors, which I was told cost like $300.00 + for one of them.....or was it 10 of them. Nevertheless, VERY expensive for an insurance to pay for.
I get this part. What I can't get a clear answer on is why when my blood glucose is steady (over several hours) that the SG can remain 50-100 points different. I'm seeing this happening more and more often and the way I monitor, calibrate, etc. has not changed.
The roller coaster model makes sense most of the time. But I frequently find that my BG (tested every 2-3 hours) is steady, but the SG rises 50-80 points. I can't find anything to explain this.
Jeannine and Greg, I am sorry to hear you’ve been experiencing this, and understand your frustration. I will make sure to have someone from my team contact you shortly to help out. Please let me know if there’s anything else I can help you with.
That comparison made a lot of sense. It was very helpful.
Glad you found the SG and BG comparison video helpful, Mary! We are committed to delivering more of the content that our community wants to see, so keep checking back.
My daughter has the enlite cgm. Our questions are: when is the best time to calibrate? How often should she be updating and should she only update sensor if her blood sugar is in her normal range? Thank you.
Those are great questions, Mary. We recommend calibrating the Enlite sensor three to four times throughout the day. Your daughter can calibrate before bedtime, before insulin, or anytime during any rate of change. However, please keep in mind, calibrating with two down arrows may decrease accuracy until the next calibration. It’s important your daughter enters her meter BG reading into the pump immediately after testing her BG. Here’s an article on Enlite calibration the both of you may find helpful: http://www.loop-blog.com/how-to-calibrate-your-cgm-system/. Please let me know if you’d like me to connect your daughter with someone from my team for additional information.
i changed my infusion set today when i was filling the tube with insulin it kept coming out soi checked the needle again and it stopped dripping out should i have chane the set cause i didn't please help
Hi Loleatha, please call our 24-Hour HelpLine to discuss your experience. You can reach someone 24/7 at 1.800.646.4633, option 3.
I too get a (sometimes significant) discrepancy between my BG and SG. Sometimes during the night my BG might be between 100 and 150 but the SG will be in the low range (ie 60) which triggers the alarm and will keep me up to the point that I off the sensor. I know this is not good, but I need to sleep. Is there a better answer?
Bill Babb
Bill, this is a great conversation to have with someone from our 24 HelpLine. I have asked that my team reach out to you.
I've been on the 760 since Feb 2018, keep getting lows everyday. Even when my sensor says 80 in auto the pump will give me a bolus. It wants to get me in the low 70s, but when I check my bg it's n the 40s and im about to pass out. I don't feel my lows.
Ansel, we've had such positive feedback from our customers using the MiniMed 670G system and I'm so sorry you’re not having that same experience. Have you had a chance to speak with your healthcare team regarding your settings? An update may help with your lows. Of course, our 24-Hour HelpLine is always available to you at 800.646.4633 option #1.
Why am I getting sensor readings at 11.8 but my BG reading is 17.1 ?? I had a low after evening meal hence it being higher but wow this is a huge difference in readings and may explain why my levels haven’t came down 3 hrs later.
This would be a great conversation to have with your local technical support team, Angela. They can troubleshoot with you and help identify the cause. You can find your local team's information here: http://bit.ly/1ce3pEc
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