Scuba Diving with dexcom G5

My only desire to do this would be for experimentation and sharing the information as a public service. Ideally, I would have a transmitter that was about to expire, so I would not be out too much if it died. If it was just for my own purposes, I wouldn’t wear it on a dive. But I am always curious on how to break things! :slight_smile:

That strikes me as potentially dangerous. Since you are inhaling through your mouth, having a piece of hard candy in there seems like a choking hazard. And what makes it worse, is if your airway got blocked and you tried to surface, you could have pulmonary barotrauma.

You know I am a gambler, but I would never put hard candy in my mouth when breathing through a reg!

You know that funny piece of plastic that one has to remove in order to insert the Dexcom sensor? It is actually a tool to remove the transmitter if needed in between sensor changes. I have used mine several times to get the transmitter off. It is an ingenious bit of plastic.

@Martina4 , since you are a pro, what do you think? Is there a safe way to take carbs in the middle of a dive?

If I remember correctly, DAN guidelines advise going up to the surface before ingesting any. But I know some divers recommend bringing glucose gels along during the dive. Would you feel comfortable with something like that?

You can get PADI certified with T1D - you will need a certification from your doctor. In my case this was a two sentence letter from my GP stating that my control was good enough to allow me to dive safely. As a PADI certified diver he will be restricted to depths of 40 metres and normal air mixtures only (no nitrox). There are even hand signals for “my BG is Low”. You can buy small waterproof dive containers that clip to your BCD to hold your emergency glucose tabs (you will need one for the buddy too)

The British Sub Aqua Club has a lot of online information on diving. When I started to dive which was around 15 years ago, there was little information from PADI, but I suspect this may have changed.

You cannot dive with a pump - he will have to go untethered and take at least a small amount of long acting insulin. The potential for long disconnect times makes it unsafe to rely on pump basal.

I have snorkelled with a Dexcom (and pump disconnected). The transmitter and sensor were fine but I never went below 4 metres depth - even as a “learner” he will be diving to 20 metres accompanied by a dive instructor. However, I would give it a go. At 20 metres you are at a pressure of 2 bar. The transmitter doesn’t have any obvious holes so it might do OK.

Don’t worry about nitrogen narcosis

www.bsac.com/core/core_picker/download.asp?id=26420

The link above will give you some tips. There’s a whole established procedure for checking BG before diving but with a Dexcom it should be easier.

Joel

Edit: Missed the post above about removing the transmitter. That might work well.

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One other thought. The excitement of diving will possibly cause the adrenaline to give him a good spike. Be prepared to treat the high BG when he gets back up on the boat! Once he gets more familiar with it, that response will settle down.

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Hi WestOfPecos , I have a friend . He has diabetes for over 30 years now and is a technical diver . I always watch out for him . But he does take gel and eats underwater when he starts feeling low. Me as an instructor would never suggest that even tough I agree is better then hard candy. And is also always good to be prepared , you never know how fast your sugar can drop

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Joel, great info in your post and in your link too!

While I have not SCUBA-dived since starting with my Dexcom, I did dive quite a bit prior. I always carried a 15g glucose gel tube with me in my BCD. While I never had to use it specifically for a hypo event, I did “waste” one to see if I could consume one quickly while underwater. It took two intakes and a bit of nasty salt water included, but I determined that I could “safely” take in 15 g of carbs while diving. The test really relieved a concern I had with SCUBA and I never looked back.

W/r/t the Dex, I would just remove the transmitter before the dive and give both the transmitter and the attachment area a good fresh water rinse, then alcohol wipe (to displace the water) before reattaching after the transmitter.

FWIW, my dive target was to start @ 100-170 mg/dl (and NOT trending down) and rarely finished a dive above 200 mg/dl; easily corrected when I reattached to the pump.

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@YogaO , that is great news! You are an experimenter like @Eric2 and myself:-)

I was thinking the same MO. My only question was - will the sensor survive the dive? I don’t see why not, and the guy on the earlier quoted thread has done it successfully.

I am assuming you started the dive with little or no IOB?

No IOB!! No IOB!!
Please, no IOB!!!

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Almost always. I think I had maybe a couple dives where I was over 200 and trending up, so I took half the correction dose.

I only had one dive (in Bonaire) where I was worried about being low, but it was actually after the dive. I had a long swim after surfacing to get back to my dinghy against the wind. When I finally got on board and tested, I was @ 73 mg/dl and I could feel the low coming on. I had glucose tablets in the dink, so I downed 5 (20g) to get me back up.

I can’t imagine a sensor not surviving the dive unless it’s older, starting to lose the adhesive, and gets pulled out when taking off the wetsuit.

Wondering if anyone on this thread did try to reinsert the transmitter after diving and if it worked? Heading on a dive trip in two weeks and wondering how to handle it. I don’t want to ditch my son’s Dexcom the whole week bc it would us some valuable info about trends in this situation (we are one year in). Dexcom said to start a new sensor after diving, but at $75 each, I am not going to do that two or three times. Also, I have read the PADI guidelines and the report from the meeting that generated them. Any advice for bolusing meals beforehand? My son is on MDI. We will reduce basal the night before. Thinking I may do half the breakfast bolus? He is pretty resistant to insulin in the morning.

I have a question… I am diving in Iceland in a week with a dry suit of course and wanted to know what people’s thoughts were on keeping the dexcom on during diving since it won’t be getting wet. Diving no more than 35 feet so pretty shallow but wanted to know if anyone knew about pressure and it affecting the dexcom??? Any help appreciated. Thanks

I am T1D and am currently DiveMaster in training with Padi. Recently forgot that I was still wearing my Dexcom G5, went on a 45feet dive for about 35 minutes. Once back at the car, my iPhone registered an ideal glucose value, and gave me a profile for during the dive, too. So 45 feet for 35 minutes no problem! Gabby diving!!!

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My son has a G6. Doesn’t seem to be a way to remove the transmitter without breaking the sensor in the process. He is 12 and I’m teaching him to dive in the pool. Any suggestions on removing the transmitter and just keeping the sensor on and using some type of wrap to keep it somewhat protected from water log…??
He loves to snorkel so this was the next step.

So, what are you doing with your CGM while you are diving. Do you normally remove it or have you been keeping it on while diving and just start the dive a little high and bring a gel pack with you if you feel low?

So I have gained a little more experience with the G5 while diving. These are my experiences only and should not be taken as professional medical advice!

  1. I have recently run an experiment (repeated about 10 times) and have taken my G5 sensor with the transmitter down on scuba dives. All dives were between 45 and 75 feet. There were a few dives as deep as 106 feet. Upon return to the boat the receiver has registered the transmitter almost immediately, and displayed my BG levels in 5 minute intervals for the entire dive. → The sensor and transmitter both can withstand 106ft scuba dives. I was wearing my 7mm wetsuit which helps with prevention of any mechanical issues under water, incl. failing glue.

  2. Do not take the receiver, as it is not waterproof. My procedure allows me to monitor immediately before I enter the water, immediately after, and gives me the history for the time during my dive. If you want data while under water you need to think pressure and waterproof but transparent containers. Not sure that is the way to go. If you control your BG before and after, you should be fine for the up to 60 minutes in the water. If not, as a professional I recommend calling the dive, which I have done several times out of caution.

  3. I have seen a significant impact of body hydration on the reliability of the readouts. If you go through cycles of hydration and dehydration the data will not be very reliable and appear “jumpy”. The same seems to be true on some occasions related to pressure. I mostly had good quality readings for times during my dives, but once in a while get noisy data readouts, likely due to a combination of surrounding pressure, hydration state, and insertion site for the sensor.

As far as BG levels go: I am trying to go in somewhere between 150-200mg/dL and then come out around 90-100mg/dL. During classes that I help teaching, especially when retrieving weights or during heavy surge, I go in a little higher just to be safe.

I recently came back from a deep dive (100+ft actual depth at 6250ft altitude), and I encountered severe problems keeping my buoyancy upon ascending around 25 ft. Turns out my BG had dropped below 55mg/dL, which could have been very dangerous at depth. So bring a gel, monitor closely, and consider energy consumption upon entry, and during the dive (surge, drift, search&recovery operations, …)

Sorry for the long response, but I hope it provides some valuable information for others, too.

I recommend this very well written article from DAN:
http://www.alertdiver.com/Diving_with_Diabetes

I actually started a thread on this question a couple of weeks ago and was surprised to find out that it is actually doable. I think there are some how-to videos on youtube about it as well. Here’s the thread:

Though I haven’t done any significant dives with my Dexcom transmitter and sensor on, I will be experimenting in a few weeks on a Cozumel dive trip. For glucose consumption, I usually keep a camelBak bladder with the on/off switch for the mouthpiece full of apple juice in my BCD pocket. The mouthpiece fits in mouth and you can control the intake without swallowing the surrounding water. I use with regulator out of mouth, and haven’t tried with both regulator and camelBak mouthpiece in together.

Obviously no readings while diving.

I’ve done a few dives to about 45ft for 50 minutes.

I would like to get some depth testing going on. Worst case is you burn a transmitter. I would encourage divers to post max depths and times that were dove and still got a reading.

The other issue is just adhesive- stay in the water long enough and it’ll fall off. Wetsuits compound that issue.

I wouldn’t dive with it if you can’t afford to burn a sensor and a transmitter.