CGM and diving

[Sgtcongo]

I am type 1 Diabetic and have used Dexcom G6 for diving for the last few years with no issues. Both in Caribbean and in Lake Superior and other local lakes. I have been down to about 110 feet without issue. I am looking at moving to a Pump and was wondering if anyone on here has experience using a Medtronic CGM for diving and whether they have had any issues diving with it? It may be required based on which pump I go with. In particular the Guardian 4 CGM is what I'm looking at.

 

[Sgtcongo]

We make CGM systems (I was Chief Scientist when MiniMed got the first CGM approved by FDA). We routinely test them to the equivalent of 100 ft salt water to make sure there were no issues. The only issue might be if you were diving dry and you used nitrox to fill your suit. You might see a very small increase in glucose compared to 21% O2 since the enzyme everyone uses has oxygen as a reactant. But the effect will be pretty small maybe a 2% increase in estimated glucose.
Bill

Bill would you know if the Guardian™ 4 sensor would work for diving?

 

[bvanant]

Guardian should be fine. Is MDT still selling Guardian, I was under the impression that they were selling a custom version of Libre
Bill

 

[tridacna]

I am type 1 Diabetic and have used Dexcom G6 for diving for the last few years with no issues. Both in Caribbean and in Lake Superior and other local lakes. I have been down to about 110 feet without issue. I am looking at moving to a Pump and was wondering if anyone on here has experience using a Medtronic CGM for diving and whether they have had any issues diving with it? It may be required based on which pump I go with. In particular the Guardian 4 CGM is what I'm looking at.

Were you using a cover on the CGM while you dived?

 

[bvanant]

Well we took Libre 3 to 200 feet (in our chamber). Still works fine. If you are in a drysuit and using Nitrox your readings might be a bit low (a few percent).
Bill

 

[Sgtcongo]

Were you using a cover on the CGM while you dived?

I did not use a cover on it, if you look close at my photo you can see I am wearing the Dexcom in it. I have now tested my Minimed CGM in Cozumel and went to 90 feet with no issues. On the Guardian 4 (Minimed) it was covered with Tegaderm film cover. You do have to watch because the salt water is hard on the adhesives. and it did fall off on my 6th day out of 7. I now know to keep an eye on that and add a new Tegaderm patch when it starts coming off.

 

[Akimbo]

I just ran across this video on an implantable CGM (Continuous Glucose Monitor) sensor that might be interesting, especially for divers and people that spend a lot of time in the water:

I used a CGM for two weeks for a health monitoring project but don't have diabetes. Pretty interesting to see how I reacted to different foods. More info:

Google: eversense 365

 

[bvanant]

The eversense is interesting but not terribly convenient unless you are really needle phobic. After a year (6 months now, a year pretty soon) you still need to remove it (scalpel and forceps) and put a new one in. Most folks you now see wearing Libre are in fact not diabetic but rather after "wellness". If you are pre-diabetic you should wear one to figure out which foods to eat (and which to avoid).
Bill

 

[Scubagermany]

Hi at all diabetics.
Please keep in mind that with the CGMs you are measuring your tissue glucose levels.
They are usually lower the the blood glucose levels (some things excempt).
Variations up two 20mg/dl are normal and show a correct function of your device.
I am thrilled to learn that the sensors can be used while diving because I have been asked that question by some patients and was unable to answer it.
I would recommend to check anyway randomly after each dive to see if the sensor keeps working.
Greetings from a German Diabetologist.

 

[bvanant]

Hi at all diabetics.
Please keep in mind that with the CGMs you are measuring your tissue glucose levels.
They are usually lower the the blood glucose levels (some things excempt).
Variations up two 20mg/dl are normal and show a correct function of your device.
I am thrilled to learn that the sensors can be used while diving because I have been asked that question by some patients and was unable to answer it.
I would recommend to check anyway randomly after each dive to see if the sensor keeps working.
Greetings from a German Diabetologist.

Yes indeed. Those of us who have developed CGM systems constantly worry about the blood/tissue kinetics. At MiniMed (now Medtronic) we published the 2-compartment model for blood-tissue dynamics and still worry about it. Both Abbott and Dexcom use published and patented "look forward" algorithms to use the CGM interstitial data to predict what the blood should be.

Bill