Abstract
Each time I jump into the water, I’m in awe of what I discover. For those of you who SCUBA (Self-Contained Underwater Breathing Apparatus), I suspect you have similar feelings. I’ve had the privilege of exploring the Great Barrier Reef in Australia, swimming alongside monk seals and green sea turtles in Hawaii, and meandering through the massive stalactites and stalagmites of the Great Blue Hole in Belize. While a SCUBA certification can be completed in a week, it takes months or years to fully understand the nuances of the craft. Participating with diabetes, though, adds some “depth” that I hope to “dive” into throughout this piece.
For many years, individuals with diabetes were barred from participating in scuba diving. That all changed in 2005, when professional societies released consensus guidelines about scuba diving with insulin-dependent diabetes. The Divers Action Network (DAN), an amazing organization focused entirely on diving safety, was one of the parties responsible for establishing these set of rules that have allowed patients with insulin-dependent diabetes to explore the reaches of the ocean. DAN has incredible resources and articles for any health professional working with scuba divers with diabetes.
The “Guidelines for Diabetes and Recreational Diving” can be found on the DAN website.
Individuals beginning their scuba dive training must undergo health screening. For those of us with chronic disease, this includes an evaluation by a health care provider. This can be completed by an endocrinologist or primary care physician, but patients should be referred to a specialist in dive medicine if additional expertise is needed. In the United States, the Undersea and Hyperbaric Medical Society (UHMS) provides helpful resources to find a professional licensed in dive medicine. Although I am certainly not an expert in dive medicine, I believe my medical training in emergency medicine and experiences with type 1 diabetes facilitate a nuanced understanding of scuba diving with diabetes.
Before every dive trip, I review the DAN/UHMS guidelines (Table 1). I typically scuba dive through guided tours at dive shops. These dives are led by divemasters, who help orient and guide divers to individual dive sites and ensure appropriate safety protocols are followed. However, the safety of each diver is their own responsibility. To dive safely, individuals with diabetes must be knowledgeable and responsible for their own health during each of their excursions.
Summary of Recommendations From the Guidelines for Diabetes and Recreational Diving
A couple months ago, I went scuba diving in the blue, warm waters of the US Virgin Islands. Knowing I had fulfilled all the criteria in the guidelines related to “selection and surveillance,” such as having an A1C <9% in the month leading up to my trip, I started preparing for the day of my dive adventure. The day before my scuba dives, I focused on adequate hydration, drinking a lot of water and sugar-free electrolyte drinks while avoiding those sugary (yet delicious) alcoholic beverages. I also pack my dry bag with my water sport essentials but also with extra water, glucagon, glucose tabs, glucometer, and snacks. For me, granola bars are the best snack between dives to keep my blood glucose ideal.
I was scheduled to do a morning 2-tank dive, meaning I would be doing 2 separate scuba dives with an appropriate time on the boat in between. Before leaving for the dive shop, I ate sugar-free yogurt with granola and some of the juiciest mango I’ve ever had. This provided a perfect amount of energy and carbohydrates before leaving for the day. I often dose reduce my insulin by about 25% so that my blood sugar rises to be between 150 and 300 mg/dL, as recommended by the DAN/UHMS guidelines.
When driving to the dive shop, I keep a close eye on my continuous glucose monitor (CGM) to make sure my blood sugars are stable or rising within the appropriate range. After checking in at the shop, I stop to talk with the divemaster. I disclose my diabetes to them and to my buddy and show them where I keep my glucagon in the case of any emergency. I keep an updated letter of medical clearance from my physician with me when I travel in case my divemaster requests it, although this is rare.
As our boat leaves the dock around 8 am, I continued keeping a close eye on my CGM and ended up giving an additional small bolus of insulin because my blood glucose was rising a bit too quickly. When we near our first dive site, I detach my insulin pump and tuck it into my bag. I don my gear and straddle jump into the blue abyss. After an amazing 50 minutes, I climb aboard the boat and after prepping my equipment for my next dive, reattach my insulin pump and check my CGM reading. I also double-check my blood glucose levels with my glucometer to make sure this reading is accurate. My blood glucose is 249, so I give myself a small bolus to keep my blood glucose stable during my next dive.
After repeating this procedure for dive number 2, it’s time to rinse off my gear and enjoy the beautiful (but bumpy) ride back to the dock. Scuba diving can be quite strenuous, especially if currents or winds are particularly strong, so I avoid any intense activity the rest of the afternoon and evening to prevent my blood glucose from dropping later in the day.
As always, every dive will vary, and every person will react differently. When I’m at all unsure, the safest decision is to avoid diving. A little extra time on the boat may be what is needed to have the best (and safest) dive the next time around!
Hopefully this guide helps you with your next patient embarking on a dive trip. When they get back, ask to see all their pictures! The ocean is an awe-inspiring ecosystem that all of us, including those with insulin-dependent diabetes, should explore. ■
Footnotes
Author Contributions
AG wrote, reviewed, and edited the manuscript.
Declaration of Conflicting Interests
AG reports no conflicts of interest.
Funding
None.
Guarantor Statement
AG accepts full responsibility for the integrity and accuracy of the finished work.
Andrew Golden, MD, is assistant professor of Emergency Medicine and Medical Education with Case Western Reserve University School of Medicine, Cleveland, OH.