Diabetes and Recreational Diving

thedivingbear
Aug 9
4 min read

Updated: Aug 16

What you should know

Dear divers,

Some of you might wonder "what if I have diabetes" and it is certainly a good idea to be aware of what you can or cannot do. I am not a doctor to be clear, but I compiled a couple of information for you. I hope it will be a useful, although short, recap.

Diabetes is a major chronic disease affecting millions globally. For long, the diving medicine community has traditionally viewed it as a contraindication for diving. Observations of successful diving by individuals with diabetes have prompted a reevaluation of this stance.

A workshop on diabetes and recreational diving, sponsored by the Undersea and Hyperbaric Medical Society and Divers Alert Network in June 2005, gathered experts to review data, discuss concerns, and develop consensus guidelines on diabetes and diving - talking about recreational diving here.

The guidelines emphasize personal responsibility (what's new...)for health and safety, advising divers to adhere to them for their protection and that of their partners.

Do you qualify

Individuals with diabetes who wish to dive must complete the same medical fitness evaluation as other candidates to ensure, firstly, that no other exclusionary conditions (e.g., epilepsy, pulmonary disease, heart disease, etc.) are present; and secondly, that there are no diabetes-related complications that could increase the risk of injury while diving.

They should hae a well-established treatment plan, well-maintained plasma glucose levels, and the ability to maintain those levels efficiently amidst the changing demands of daily activities. Candidates and divers with diabetes must undergo an annual medical examination, and if they are over 40 years old, they should be regularly assessed for silent cardiovascular disease. Well, that last piece if valid for all of us I guess, diabetes or not!

How to dive with diabetes

Completed the fitness evaluation and standard scuba training? Good job. Now, do follow the diabetic diving protocol. You should dive only in favorable environmental conditions, without any overhead obstacles. Your dives should not exceed a depth of 30 meters (100 feet of sea water), last longer than one hour, or involve mandatory decompression stops.

Divers with diabetes should have a buddy who is informed about their condition and knows how to respond appropriately in case of a hypoglycemic event. It is advised that the buddy does not have diabetes.

Glucose management on the day of diving

Divers with diabetes who are on medication that may increase the risk of hypoglycemia should follow a protocol to manage their health on diving days.

Have oral glucose in an easily accessible and consumable form both at the surface and during all dives. The dive buddy or someone at the surface should be trained in using glucagon (don't assume the dive operator/ dive master or dive instructor have that knowledge). If signs or symptoms of hypoglycemia are detected underwater, the diver should ascend, ensure positive buoyancy, consume glucose, and exit the water. An informed buddy should be ready to help during this process. Using an “L” signal with the thumb and index finger is suggested as a signal for suspected hypoglycemia.
Blood glucose levels should be checked after every dive. Decide on the appropriate response based on their plans for the rest of the day. It is important to note that the blood glucose requirements remain the same for any subsequent dives. Given the potential for delayed decreases in blood glucose levels after diving, it is strongly advised to check levels frequently for 12-15 hours after diving.
Divers with diabetes are strongly advised to ensure proper hydration on diving days (well, applicable to all divers regardless). High blood glucose can lead to increased urination. Although data is limited, evidence from divers with diabetes suggests that an increase in hematocrit observed after diving (indicating dehydration) can be prevented by intentional fluid intake. A bit technical, in short, drink more water!

For those who want to go further

Informative list from the DAN (reference at the end)

Age ≥18 years (≥16 years if in special training program)
Delay diving after start/change in medication:
- Three months with oral hypoglycemic agents (OHA)
- One year after initiation of insulin therapy
No episodes of hypoglycemia or hyperglycemia requiring intervention from a third party for at least one year
No history of hypoglycemia unawareness
HbA1c ≤9% no more than one month prior to initial assessment and at each annual review
- values >9% indicate the need for further evaluation and possible modification of therapy
No significant secondary complications from diabetes
Physician/Diabetologist should carry out annual review and determine that diver has good understanding of disease and effect of exercise
- in consultation with an expert in diving medicine, as required
Evaluation for silent ischemia for candidates >40 years of age
- after initial evaluation, periodic surveillance for silent ischemia can be in accordance with accepted local/national guidelines for the evaluation of diabetics
Candidate documents intent to follow protocol for divers with diabetes and to cease diving and seek medical review for any adverse events during diving possibly related to diabetes

Scope of diving

Diving should be planned to avoid
- depths >100 fsw (30 msw)
- durations >60 minutes
- compulsory decompression stops
- overhead environments (e.g., cave, wreck penetration)
- situations that may exacerbate hypoglycemia (e.g., prolonged cold and arduous dives)
Dive buddy/leader informed of diver’s condition and steps to follow in case of problem
Dive buddy should not have diabetes

Glucose management on the day of diving

General self-assessment of fitness to dive
Blood glucose (BG) ≥150 mg·dL-1 (8.3 mmol·L-1), stable or rising, before entering the water
- complete a minimum of three pre-dive BG tests to evaluate trends
Sixty minutes, 30 minutes and immediately prior to diving
- alterations in dosage of OHA or insulin on evening prior or day of diving may help
Delay dive if BG
- <150 mg·dL-1 (8.3 mmol·L-1)
- >300 mg·dL-1 (16.7 mmol·L-1)
Rescue medications
- carry readily accessible oral glucose during all dives
- have parenteral glucagon available at the surface
If hypoglycemia noticed underwater, the diver should surface (with buddy), establish positive buoyancy, ingest glucose and leave the water
Check blood sugar frequently for 12-15 hours after diving
Ensure adequate hydration on days of diving
Log all dives (include BG test results and all information pertinent to diabetes management)