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Continuous glucose monitoring CGMS

Houston CGM continuous glucose monitor. Iprohouston CGM continuous glucose monitor dexcom

A continuous glucose monitoring system (CGMS) is an FDA-approved device that records blood sugar levels throughout the day and night.


There are several approved devices -- Medtronic iPro device, DexCom G4, G5, or G6 device, and the Abbot Libre systems, for example (details below) -- that can provide up to many blood sugar measurements continuously.  The doctors at Houston Thyroid and Endocrine use this technology to help manage a patient's blood sugars.

How is it placed?

First, a tiny glucose-sensing device called a "sensor" is inserted just under the skin of the abdomen. The insertion is quick, and is usually not painful. Tape is used to hold it in place.

The sensor measures the level of glucose (painlessly) in the tissue every 5 minutes and sends the information via a wire to a cell phone-sized device monitor that you attach to a belt or a wireless device in your purse/pocket. The system automatically records an average glucose value every five minutes for up to seven days.

When is this used?

The continuous glucose monitor is now intended for day-to-day monitoring or long-term self-care, and it is a replacement or equivalent to standard blood sugar monitoring.  It gives trends.  This helps your health care team make the most appropriate decisions regarding your diabetes treatment plan.
Here are video tutorials:

Is it accurate?  NO and neither is your glucometer. But it is precise. 
The gold standard blood sugar is obtained from whole blood at a laboratory from your arm and this would be the most ACCURATE blood sugar. Within a range of 80-150 all glucose meters and CGM (Dexcom, Libre, Enlite, Eversense)  are approximately  plus or minus 15% versus whole blood.  The same applies to any blood glucose meter as well. Therefore, a blood sugar meter and a continuous glucose monitor  could potentially be up to 30% different from each other. Both devices however are PRECISE within their own measurements and can be used for trends. This difference worsens with more extreme lower or higher blood sugars. Example image to explain accuracy versus precision is here:


Comparisons between Libre and Dexcom:

**********PLEASE BE AWARE IF YOU OBTAIN A CGM AND YOU WOULD LIKE FOR US TO HELP YOU PUT IT ON, PLEASE CALL THE OFFICE 713-795-0770 OR SEND PORTAL MESSAGE TO SCHEDULE A DATE FOR A 30 MINUTE TRAINING.

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-------- Continuous glucose monitoring systems (CGMS) ------
There are two primary free-standing CGMS which are quarter-sized devices that are taped on you to provide blood sugar readings every 5 minutes without a finger stack each time. Each system has its pros and cons. If we would like you to try both out to determine which is most affordable and best for you.
COMMERCIAL INSURANCE PATIENTS (non-Medicare):
1) Freestyle libre systems will be ordered directly to your local pharmacy. You will need to have our office send the prescription
2) Dexcom systems -
If we send your Dex-com G6 prescription to the Walgreens Specialty Pharmacy (281-578-8884) or to your mail-order pharmacy, please contact these pharmacies after 10-14 days if you have not heard from them.
Patients should call 1-888-738-3646 and tell them to send Houston Thyroid and Endocrine for a request to order. Our fax number is 713.795.0855. Your last office visit with the doctor must have occured within the last 6 months and the doctor should have already discsused with you.
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MEDICARE PATIENTS:
1) For a Freesyle Libre patients should call 1-855-632-8658 and tell them to send Houston Thyroid and Endcrine a fax with the request for order. Our fax number is 713.795.0855. Your last office visit with the doctor must have occured within the last 6 months and the doctor should have already discsused with you
2) For Dexcom systems--If we send your Dex-com G6 prescription to the Walgreens Specialty Pharmacy (281-578-8884) or to your mail-order pharmacy, please contact these pharmacies after 10-14 days if you have not heard from them. Patients can call 1-888-738-3646 and tell them to send Houston Thyroid and Endocrine for a request to order. Our fax number is 713.795.0855. Your last office visit with the doctor must have occured within the last 6 months and the doctor should have already discsused with you.
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TRAINING: Once a commercially insured patient has received a device they can request a virtual televisit for training. Please send a portal message. Medicare patients should contact the device company for training.
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COMPARISONS OF EACH SYSTEM:
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Dexcom system:
-Sensor lasts 14 days and is waterproof.
-Taped on your abdomen or arm, not in your body
-New reading to receiver or smartphone every 5 minutes
-Proactive Personalized alerts on receiver or phone
G6 version is pre-calibrated so NO finger sticks anymore, just like Libre
In order to set up an in-person training with a Dexcom representative, patients can contact Dexcom CARE at 1-877-339-2664 Mon-Fri 7:30 AM-10 PM CT or email patientcare@dexcom.com .
Houston Thyroid and Endocrine can set up a virtual training in the office and in some cases at your home (not for medicare or humana or aetna patients)
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Freestyle Libre
-Sensor lasts 14 days
-Glucose measured every minute but can only be viewed by scanning the sensor
-Cannot alert user of low or high BG without scan. NO proactive alerts
-Device is factory-calibrated and does not require fingerstick calibrations
-Generally lower cost than Dexcom
Most patients are able to self-train by using the detailed tutorial videos available online at https://www.freestylelibre.us/support/overview.html . If they want to meet with a rep, they can call 1-855-852-4527.
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Dexcom might be the right CGM for you if...
1) You are on multiple daily insulin injections or an insulin pump.
2) You experience hypoglycemia (<70 mg/dL), especially overnight.
3) You are willing to do at least 2 fingersticks daily with your current blood
sugar meter.
4) Your caretaker or loved one wants the capability of viewing your BG
readings from their own smartphone (Dexcom Share).
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Freestyle Libre might be the right CGM for you if...
1) Dexcom CGM is too expensive.
2) You have trouble with daily fingersticks.
3) You prefer a device that does not alarm at all.
4) You are not on insulin but would like to see more of what happens to your
blood sugar during the day (in response to meals, exercise, etc.).
5) You have watched the Dexcom sensor insertion video online and would
prefer a more simple insertion process.
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INSURANCE COVERAGE
Dexcom systems are covered either by your pharmacy benefit or your durable medical equipment insurance benefit. We can send an inquiry and you should receive then receive a call from dexcom with your costs in about 10 days.
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Libre systems are covered with your pharmacy benefit only and is avaialble at certain local pharmacies. 
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