Diabetic Diving

[JDMerk]

My father is a type I, insulin dependent diabetic. He has been since he was 13. However he is a NAUI OW certified diver since 1977, but he may have dove a handful of times since then.
I just earned my NAUI AOW and am already an addict. I would like very much to share my new hobby with him and dive together when we go on our annual family vacation to the NC outer banks.
The only problem is that I am concerned about his diabetes. He is insulin dependent but he has been on an insulin pump for 7+ years. His blood sugar has been managed very well his whole life but particularly well since the pump. As diabetics go he is in very good health, he has no outstanding medical issues other than the diabetes and is in his early 50's.

I want to get him in the water but am not sure if its safe, before I got certified we went hookah diving to 20' but the dive op wouldn't let him do any more than snorkle, even as a certified diver. Their reasoning was because he was a diabetic.

Are there any diabetic divers on the board or do you personally know any or have experience with one? What special issues do they have to contend with?

PS. My mom is OW certified since 1978 but I cant drag her in the water with an anchor...she wants nothing to do with SCUBA other than taking pictures from the boat

 

[bleeb]

This subject is frequently discussed, both here on ScubaBoard and in dive medicine circles. For example, have a look at the following recent threads:
Diving & Epilepsy
New to diving not to diabetes
Diabetes and diving
Also, DAN has this to say about diabetic diving.

As you can see, it used to be an absolute contraindication, although now some people are allowing exceptions under certain specific conditions. In your particular case, one thing to check would be whether your dad's pump can take the increased pressure if he's going to dive with it (most medical devices don't seem to be pressure-rated), or adequately sealing the somewhat open wound if he's not.

BTW, as a general recommendation to ScubaBoard newcomers: If you're looking for "collective knowledge", don't be afraid to try the function. Many common issues have been talked over at length, and there will probably be far more information already collected in an existing extended discussion than gets posted in response to a new thread.

 

[HBO MD]

Another thing to remember about diabetes and diving is that insulin sensitivity changes with depth, such that less insulin is required to achieve stabilization. This is due to the effect of pressure on insulin receptors. It also doesn't take into account the effect of muscle activity or exertion on blood glucose and the effects of exogenous insulin.
I would advise against it, as the risk of hypoglycemia at depth is very real.

 

[SteveAD]

The only person even remotely qualified to answer this question would be a physician who is well acqualinted with your dads medical history.

 

[ppo2_diver]

Another thing to remember about diabetes and diving is that insulin sensitivity changes with depth, such that less insulin is required to achieve stabilization. This is due to the effect of pressure on insulin receptors. It also doesn't take into account the effect of muscle activity or exertion on blood glucose and the effects of exogenous insulin.
I would advise against it, as the risk of hypoglycemia at depth is very real.

Do you have any resources about this? I haven't heard of this yet and would like to learn more.

 

[TSandM]

Another thing to remember about diabetes and diving is that insulin sensitivity changes with depth, such that less insulin is required to achieve stabilization.

I hadn't heard of this, either, but a quick search of the Rubicon archives pulled up a bunch of papers confirming that hypoglycemia is a real phenomenon during hyperbaric treatment of diabetics, and far rarer and less significant in normal controls. Thank you, HBO MD, for posting this -- I learn something every day!

 

[nereas]

See if you can find a local scuba store that would train and certify a Type 1 diabedic.

I am guessing that you won't.

You can also call DAN and see what their physicians say: 1-919-684-2948. It's printed on the back of your card.

If you don't have a card, get one soon.

I am surprised that TS&M did not share her opinion. She is a surgeon.

 

[HowardE]

While I'm not a doctor, nor do I play one on TV... I did have a conversation with a hyperbaric physician 2 weeks ago about PO2 and toxicity. An interesting tidbit he told me is that under higher PO2's - it causes your blood sugar to drop. According to him... he's had people "tox" in the chamber and while it appeared to be ox-tox (overtly) - the data revealed that it was a diabetic seizure.

Something to look into if you are diabetic...

 

[TSandM]

It's fairly clear, from the DAN publications, that diabetics, given a number of factors, can dive with reasonable safety (remember, diving is a sport of risk assessment, because the only truly safe dive is the only you don't do). Some diabetics -- those who are very brittle, poorly compliant, easily go into ketoacidosis, or are unwilling to exercise the discipline required -- should not dive at all. Any diabetic who dives needs to inform his buddy or buddies of his problem,the potential symptoms, and what rescue glucose source he is carrying and where.

I would concur that one would have to investigate the performance of the insulin pump under pressure, or work out a pump-independent insulin regimen that reliably kept blood sugar in an acceptable range.

I'm not big on telling people, "You can't do that." I think adults should gather data and assess risk. In this case, there is quite a bit of information available about diabetics and diving, and the individual diabetic can compare his own disease and control to the parameters that are published, and decide whether it is reasonable that he will be able to design a glucose management strategy that will keep his blood sugar high enough to prevent any neurologic impairment, and low enough to keep him from getting DKA. For some people, the answer will be yes, and for others, it will clearly be no.

 

[HBO MD]

Hi Guys,
I'm actually a Hyperbaric Physician and a Critical Care physician so my experience is in real time and not theoretical. I just want people to dive as safely as possible ; hence I am happy to share my thoughts, ideas and experience. Ultimately it is up to you guys.
People are absolutely correct ; before one can make a categorical decision about your dad, they need to be clear about his history, diabetic control, any complications, the type of pump etc.
To my knowledge, there are no pumps in clinical use that work in any other way, than basal rate with incremental doses of insulin. In other words, there are no pumps yet which function through feedback loops to correct for blood glucose levels. This is part of the goal as is islet cell transplantation etc for optimal therapy of diabetes. But these solutions lie in the not too distant future and aren't yet relevant to this discussion.
Nevertheless, hypoglycemia at depth is related to altered receptor sensitivity. By the same token, as we exert ourselves, hormones are released which antagonize the effects of insulin, such as adrenaline ; particularly if we are under stress, while muscle activity enhances insulin activity to promote muscle tissue glucose uptake. Confused yet? I don't blame you. This means that the direction of blood glucose shift is not always clearly predictable. In the resting patient lying within the chamber, we preempt a decline by decreasing insulin infusions/doses and increasing glucose infusions. In the field this is not as straight forward for the reasons I've outlined. So there are a number of options ; run high and avoid a hypo. Some people might suggest that, however, glucose is a potent diuretic and draws electrolytes with it which could destabilize the blood chemistry and precipitate heart arhythmias for example. In addition, there is the risk of diabetic keto acidosis. A similarly very serious complication arising from a relative lack of insulin. It would be important to know if your Dad has experienced this before, and if he is prone to such a complication.
Others may advocate to leave his infusion rates since many diabetics can relate when they are going into hypo. However, this is on land when they can ingest some orange juice or candy. That would be challenging at 60'. With increasing diabetic complications, the nervous system is damaged and those signs, such as sweating, fast heart rate etc may not occur with altered conscious state being the first and only signal that metabolic mischief is at hand. At depth, this adds the risk of aspiration, hypoxia, hypercapnia etc transforming a problematic situation to a potentially lethal one.
And I have not even touched upon the complicating factors of any additional medications which he may be taking.
So the question remains as to what is the solution? Experiment in a chamber to determine blood glucoses and a potential insulin profile? Unfortunately this does not take into account temperature or work load.
Hence my recommendation. I realize that this is based upon a very rudimentary outline of the situation, but I also realize that you very much value your father's participation. And I hope he can share your experiences for many years to come.
Good luck with your search for answers and coming to a well informed decision that will support your dad's physical well being.