Monday, December 18, 2006

Day Seven: CGM Trial

I went to see my doctor today and got a new batch of supplies for the Navigator. I also learned briefly to use the software and I really like what I've seen.

My favorite part of the software is a Daily Combination page that shows blood sugars on a line graph and meals directly below the blood sugars, using circles that are relative in size depending on how many carbs are eaten. Below that is a bar graph showing insulin dosage. I am a very visual person, so I completely dig the small and large circles, right under the line graph. It is so easy to see where you need adjustments based on pre-meal, post-meal and all in relation to insulin dosages. When I get the software downloaded (after the holidays) I will post a screen shot of this page. With the software I went over my readings with my doctor and it was great. We were able to balance my basal vs. bolus ratio in a way that never would have been possible with 4-6 finger stick tests. He loved seeing the line graph floating in the low side of my goal range for hours and hours.

I inserted a new sensor in my left arm this time and it bled for a bit, but we dabbed at it with the corner of gauze until it stopped. Totally no big deal. The insertion was relatively easy. I twisted my straight arm and crossed it over my chest so I could reach the back ; where most folks tend to do injections. I was able to do it one handed, but I would need a mirror to check the insertion and check for blood which can impact the sensor negatively if there is too much. It was a little tough to get the transmitter snapped into the sensor today. Not sure if it was my arm postion or the unit.

I did not use Tegaderm as I need to remove the sensor Wednesday morning and I'd like to see how well the adhesive does this time. I have to wait 10 hours from insertion to get readings.

Basically, the 10 hour window is said to be there because when you poke a hole in your skin, there is trauma. The tissue needs time to heal before it can take readings of the interstitial fluid effectively. That could be two hours with some people and much longer with others, so ten hours should be safe for most everyone to get good readings. Once the ten hours are up I will calibrate the Navigator with a finger stick, using the Navigator receiver, which is also a stand alone meter. I will have to check again in two hours, so that will be late tonight.

Next post I'd like to start a dialog about cost and insurance. I am very concerned about the cost of CGMs and sensors, as well as the timeline when insurance campnaies will begin picking up some of the bill. This technology WILL save lives and WILL save $$$ in emergency room care, not to mention the opportunity to prevent or prolong the onset of serious complications.

I should note that my decision to start this blog was because I felt totally compelled to share this information with my family and anyone interested in the technology. It is not monitored by anyone with the study, in fact, they have no knowledge of this blog. The information I am communicating is based soley upon my personal experiences. I am not a doctor, just a woman living with diabetes and caring for a chld with type one diabetes. If you have any questions about whether a CGM is right for you, talk with your doctor.

Ahh! My navigator just beeped for my first calibration--150 and doing great. Let the readings begin!


Anonymous said...

Just want to thank you for your blog, I check it everyday! We are all eagerly waiting for more info about Navigator.

On paper it suppose to be better that DexCom/Guardian, I hope it is true. We used DexCom but is not satisfied with the accuracy, even though we found it useful. If Nevigator is as good as it seems to be, based on your post, we will definitely try to get one when it is out!

p.s. I did not see you comparing Navigator with finger sticks, is that because it is forbidden by the clinical trial rule? If not, could you post some comparison? Thanks!!!

Wendy Morgan said...

I have done a few tests against my own BG meter and the results have been very similiar, within 10.

I have really enjoyed NOT taking my blood sugar with finger tests, so I have not done comparisons often and will do some in the next few days, after my travel.

Gary said...

Sounds like the software might be more useful than what I use for DexCom. I have to manually transcribe handwritten detailed notes regarding insulin boluses and carbs, etc., onto the reports that DexCom gives, with a pencil; extra work that I would like to cut out, and it makes the analysis more difficult.

For me, accuracy with the DexCom has not been an issue, except if you're trying to calibrate with the one touch ultra meter when you're in a wild swing, or either very high. Low numbers seem to be quite accurate in comparison with the BG meter, which is what I'm really interested in, in addition to adjusting my basal rates for my Animas 1250 pump.

I have found that the sensors get more accurate with time, and after a couple of days, DexCom tracks closely with my ultra.

I'm very interested in hearing more! Any issues with water? You've got to be very careful with the Dex, it's not waterproof so one needs to use tricks to keep the water from showers affecting the results.

Thanks again!

Gary (

Wendy Morgan said...

Regarding water and the Navigator; the tansmitter and sensor are waterproof up to a depth of three feet (where it has been tested). I do not need to remove it to shower or hot tub, but the receiver needs to be away from the water and has a range of ten feet.

So, if the receiver is by the pool and you are swimming within range, you could still get a warning if you are getting low. Darned cool!