Sunday, 30 June 2013

CGM/Sensor

I recall writing a post on my CGM before, but I think I rushed it so I'd like to take the time to write a more detailed post on my own experiences with it.

I have been wearing my Continuous Glucose Monitor, or sensor- for the past few days and I'm due to take it off on Monday. I have a Medtronic Paradigm Veo insulin pump so I use the Medtronic enlite sensors in collaboration with the integrated CGM feature on the pump. It's a wonderful thing to have and I love looking at my insulin pump and knowing what my blood sugars are doing, I know the sensor has a bit of a lag time and takes a few minutes to catch up, but most of the time it's only a couple of points off and sometimes it's actually spot on which is very helpful.

I wear the sensor on my stomach, which is the most common site that I use for sensor insertions- it just feels comfortable for me there although sometimes it is annoying trying to get it to stick in a place that is not underneath my waistband as it was recommended at sensor training not to wear it under a waistband as it may affect the connection between the pump and sensor.

The very first time I wore the sensor, it was a blind session as I didn't have the pump- so I couldn't actually view my results in real-time, I wore the "blind sensor" about two times before I finally got my insulin pump. This was extremely beneficial for both myself and the hospital because we managed to see what my blood sugars were doing during the night. However, I did not like wearing the sensor at the time because for one, it didn't have an inserter so the insertion was done by hand which freaked me out a little bit and it hurt, to get straight to the point if I'm honest. It was pretty uncomfortable, but I didn't flinch and the nurses were actually really surprised by my bravery.

Every time my diabetes team would suggest wearing the sensor I would turn it down simply because I didn't fancy going through the insertion as I really didn't like it. Then, a new sensor was released which is the best thing because it has an inserter, it doesn't have to go in at a funny angle and it is much more accurate than the old one- the old ones were called iPro, the ones that I use now are called Enlite. It is simply brilliant in my eyes because it means I am now not so afraid to wear the sensor because it is a more comfortable experience than before. (But I'm still a little afraid of it, even though it hardly ever hurts that much)

When I insert the sensor under my skin, I have to wait for the green light to flash on the "mushroom" as I like to call it, to let me know that it is connected- let me tell you that is a very tense moment; if it doesn't flash you need to remove the sensor and fire it in all over again- No thank you! On Wednesday it took around three minutes to flash, I was just about ready to crawl into a cave. Anyway, then I have to go into my pump and connect the sensor to the pump via it's snazzy little 'Bluetooth' connection that goes underway once I turn on the sensor and it takes me through the sensor settings and then a little funky graph appears on my pump screen and says 'Warm up'. I stick 'IV3000' over the sensor to hold it in place then I'm ready to roll.

It takes the sensor a little while to warm up and then it will alert me to test my blood sugar to calibrate it- once I enter my blood sugar it gets to work and then over the days that I wear it, my blood sugar will appear to me on a little graph and I can see the graph over 3 hours, 6 hours, 12 hours or 24 hours. In the settings, I can also set high and low glucose alerts, so that the sensor will alert me when my blood sugar is too high or too low. I can also do other things such as prediction rates, where I will be alerted if my blood sugar is rising or falling and I can stop a high or low blood sugar before it happens- which is very helpful. Other features include low suspend, where the pump will automatically suspend itself if my blood glucose falls to low- a total lifesaver during the night.

The low suspend feature has come into play a couple of times but there was one occasion in which I believe it probably quite literally saved my life. My friend slept over that night and in the morning she told me that my pump was alarming, she was trying to wake me up but (because I'm such a deep sleeper) I didn't wake up and she didn't know what to do so she just went back to sleep, she told me that when she woke up she thought the noises from my pump were a bomb, I laughed a lot when she told me this. Anyway, I checked my pump immediately after to see why it was making such a fuss and vibrating against my hip...the screen read "I am diabetic. Call for medical assistance" err? I thought "what? I am in no need of any medical assistance?" I soon realised this was the message that my insulin pump gives when it goes into low suspend for a long time with out it being addressed, obviously I was asleep so I was unaware of my low blood sugar- I looked back at my graph and to my dismay my blood sugar had fallen very low during the night to about 2.5mmol.

I scrambled through my bag for my tester and my blood sugars were 9mmols, exactly what it said on the sensor. It was scary to think that if it wasn't for my sensor suspending my pump and stopping insulin delivery plus, my trusty glucagon producing liver, things might have been a whole lot different. That event made me truly appreciate how lucky I am to have a CGM.

There are some drawbacks to wearing a sensor but they all depend on how the person can cope with annoying alarms, an extra needle to conquer, wearing another object on their bodies (if they already wear a pump)...things like that. On occasions the sensor may stop working but for me this only really happens when it is coming to the end of it's six days of action, or sometimes it may lose connection with the pump but it soon reconnects after I move them next to one another. (it did this yesterday and I had to move my insulin pump over to the same side as my sensor, but then once it reconnected I could move it back)

A frustrating thing about the CGM is that it needs to be calibrated, I don't mind doing this during the day- but it's the times when it needs calibrating during the night that are the worst. If it doesn't get calibrated it will stop receiving blood sugars as it needs "updating" so to speak, to help it along the way in staying accurate. If I don't wake up to it's alarms during the night I will be missing readings for a few hours which annoys me, plus it makes my graph look ugly!

However, those small annoyances are a small price to pay for the benefits that the CGM brings. It has helped me so much. To be honest, it has also helped me mentally to control my blood sugars- seeing good sensor graph results really encourage me to continue doing the best that I can do to keep my blood sugars in a normal range, it makes me really happy to see good results and it also really reassures me that I'm on the right tracks.

For example, the other day during my hospital appointment, we changed my basal rates during the night because the results from my CGM revealed that during the early hours of the morning my blood sugar peaked from what is known as the "dawn phenomenon" but then around 7 or 8 in the morning they begin to fall and if I sleep in late on weekends or days off school- I find that I almost always wake up low. So adjustments were made to try and fix this problem and now I am wearing the sensor to see if these basal rates are working for me and so far so good- the line on the graph stays pretty stable all throughout the night which makes me happy and I haven't been waking up low or going high during the early hours of the morning!

Now, when I take off the sensor on Monday, I can send off my results to my diabetes team at the hospital and they can take a look at them and know that we are heading in the right direction with my basal rates and blood sugar control. It's just very reassuring to have something that really helps me to gain tighter glucose control, especially because I am always doing different things and experiencing different factors that will affect my blood sugar such as hormones and stress- my sensor helps me to get to know my body better and the effect that different activities have on my blood sugar to make way for an easier life with type one diabetes.

I am very tired now though so I am going to head off to bed; I hope you found this useful and gained some insight into how the sensor works. If you have any questions please do not hesitate to ask me any questions because I love answering questions c:

Goodnight.

-Ellie
[Peace&Insulin]

2 comments:

  1. My sensor is called a Dexcom. It's unfortunately not connected to my insulin pump so i have a 'diabetic ipod' as i like to call it that has the graph and stuff. i have to calibrate mine at 10 in the morning and then 10 at night. Mine lasts me for a whole week. The insertion scared the shit out of me the first time (you can watch the video at www.dexcom.com) it's not that bad anymore. i quite like it now. i wear it on my stomach also because no one can see it during dance class which is very helpful when i don't want people to know. how long have you had the CGM? I've had mine about four months.

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  2. Thank you . This is very helpful

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