Recreational Diving Medical Screening System

The diver medical form, with or without the physician evaluation, is a status assessment. There is no inherent expiration date, but completion dates are included in both the participant questionnaire and physician evaluation form.

Organizations (or individuals) choosing to use the form can apply their own standards for currency.

For example, an instructional entity may decide that new students should provide forms completed within three months of a program start date. An event organizer may have different requirements. Additional standards can be applied where appropriate.

Many issues related to diving may not be good indicators of future risk.

A history of DCS, for example, could be associated with increased future risk if the diver is cavalier and ignores safety protocols. But it could also be associated with reduced future risk if the diver took an earlier case as a warning and increased conservatism and thoughtfulness.

Complicating the picture further, it is also possible that a diver experienced DCS as part of a controlled study of decompression stress. In this case, the outcome may well have not been related to diver decision-making, and the quick treatment that would be provided as part of the study is not known to increase future susceptibility.

The bottom line is that such a question would have a greater likelihood of being pejorative than truly useful.

The questionnaire was developed to uncover areas of concern with some subtlety, and with thought given to how information might be used and misused.

No. The value of the form is dependent upon honest and correct answers. Efforts to hide issues can result in seriously compromised safety. Honest reporting is critical to identify risks, some of which may not be apparent to the person completing the form.

Ultimately, the screening materials are intended to help the community

Close blood relatives are biological parents, grandparents and siblings.

As a diagnosis, the range of symptom severity and history with this disease varies greatly. Exacerbations and disease control are the principle areas of medical decision making related to fitness to dive evaluations.

Asthma is a topic of interest for diving medical examinations, and our primary focus as physicians is on how well someone is controlled as well as their triggers for exacerbation, not just whether they have asthma or use inhalers. Inhaler use per se is not a stand-alone disqualifier.

The goal of the questionnaire is to find those who have had exacerbations within the last year, as an indication of their overall disease control.

BMI is not a measure of body composition; it is simply a height-weight ratio. It can be informative, but it can also be misleading. BMI values will be higher for individuals with larger frames and greater muscularity, or lower for those with less muscle and more fat mass. Healthy body composition and general cardiac fitness are important, but these cannot be confirmed with BMI data.

Imaging, whether standard CXR or CT, may or may not correlate clinically, are frequently not ordered as a standard on everyone in the outpatient environment either to make the diagnosis of pneumonia nor in follow up.

Fit-to-dive determinations related to a history of pneumonia are based on the medical and clinical history and current health status.

Depending on health history or clinical status at the time of evaluation, pulmonary function tests may be performed as well as imaging, but there is no single approach that would appropriately apply to all divers.

The type of imaging study ordered by physicians will depend upon the clinical history and/or examination. In cases where a higher resolution is desired, CT scans are often preferred.

The cardiovascular system is critical for diving health. As such, heart disease, as well as conditions that are associated with or contribute to it, elevate to the medical concern about diving safety.

Obstructive sleep apnea (OSA) is an independent risk factor for heart disease and is frequently associated with other risk factors or disease processes that either individually or collectively increase an individual’s risk of sudden incapacitation while diving. While not all those with OSA are at definable risk of heart disease or sudden incapacitation, it is worth describing the potential issues associated with OSA from the perspective of a screening questionnaire and diving safety.

The incidence of obstructive sleep apnea is highest amongst obese males, due in part to male pattern fat deposition to the neck and posterior tongue, which increase the risk of airway compromise when lying flat. Associated risk factors for heart disease include obesity, hypertension, elevated cholesterol, and diabetes. Some or all of these conditions are commonly seen either independently or as part of the health history in people with OSA.

Obstructive sleep apnea is not simply about pauses in breathing. Apnea places strain on the right ventricle (the chamber of the heart that pumps blood to the lungs). Over time, this strain increases ventricular muscle size, which elevates the risk of heart failure, as well as rhythm problems (arrhythmias), especially atrial fibrillation. Cardiac arrhythmias may spread to the ventricles, which carry a marked risk of incapacitation. Atrial fibrillation carries additional concerns related to blood clot formation in the heart, pulmonary embolisms, stroke, and reduced exercise tolerance. People with atrial fibrillation are frequently on blood-thinning medications, which is an additional health concern for divers.

If the questionnaire highlights the need for a medical examination, please bring this material (including the Diving Medical Guidance) to your physician.

If your physician wishes to discuss your case with a specialist in diving medicine, they may contact DAN, free of charge.

The Diving Medical Guidance material is currently available in several languages, and they may be viewed here. Additional translations may be added in the future.

The "additional comments" box was expressly removed from the medical form because it can create more issues than it solves. Depending on what is written in such a box, recipients of the signed form could be put in a position of having to make judgments that are outside their expertise. The physician's evaluation form was intentionally kept simple. The status of "Approved" or "Not approved" requires no hand-wringing by those who must decide if they can accept the form. Decision-making could be much more difficult with extra text.

Additional guidance can be provided to divers in separate documents. These can be generated as notes or letters, including guidance and/or practice agreements between patient and physician to help ensure best practice.

Our understanding of the impact of COVID on both short-term and, in some cases, longer-term health continues to evolve. It is clear that critical systems can be affected in ways that could produce serious risk to divers. We have revised the medical screening tool to focus on symptoms most likely to be problematic. It remains essential for anyone with health concerns or compromise to be medically evaluated prior to diving.

For additional information, see:

UC San Diego Guidelines for Evaluation of Divers during COVID-19 pandemic: https://www.uhms.org/images/Recreational-Diving-Medical-Screening-System/forms/Diving_Medical_Guidance_EN_English_2021-01-29.pdf

DAN Alert Diver bulletin April 2021: https://alertdiver.eu/en_US/articles/what-you-should-know-about-diving-after-covid-19

An axiom of diving medicine is that those with epilepsy are considered at an unacceptably high risk of sudden incapacitation, and therefore are most frequently not medically cleared to dive.

However, a history of seizures (especially those induced by trauma, surgery, or medication) does not equate to a diagnosis of epilepsy nor necessarily constitute a lifelong risk of seizures.

A recently updated definition states that “Epilepsy is a disease characterized by an enduring predisposition to generate epileptic seizures and by the neurobiological, cognitive, psychological, and social consequences of this condition. A seizure is an event and epilepsy is the disease involving recurrent unprovoked seizures.” (https://www.epilepsy.com/article/2014/4/revised-definition-epilepsy)

The importance of this definition is that the diagnosis of epilepsy requires ‘unprovoked’ and recurrent seizures. It follows that if you have not had any seizures off medication for more than 20 years, your risk of a seizure is statistically equivalent to the general population.

The following quote comes from the website above and is a more explicit explanation of the clinical diagnosis:

“1. At least two unprovoked (or reflex) seizures occurring greater than 24 hours apart.

2. One unprovoked (or reflex) seizure and a probability of further seizures similar to the general recurrence risk (at least 60%) after two unprovoked seizures, occurring over the next 10 years.

3. Epilepsy is considered to be resolved for individuals who had an age-dependent epilepsy syndrome but are now past the applicable age or those who have remained seizure-free for the last 10 years, with no seizure medicines for the last 5 years.”

In conclusion, if you have been seizure free off any kind of antiseizure medication for a sufficiently extended period of time, we recommend that you seek a neurology evaluation. If cleared by the neurologist (they may perform an EEG and/or other studies) and that doctor determines that you do not have epilepsy, then you could be cleared to dive.

The short answer is that in-person examinations are not always necessary or required. The utilization of telemedicine, especially during the current pandemic, can be an effective mechanism to provide appropriate efficient healthcare. One of the primary goals of the revised diving questionnaire was to reduce the number of physician evaluations required, while still providing enough screening sensitivity to catch issues that may warrant further evaluation or examination. The screening questionnaire does not state that face-to-face evaluations are required. Ultimately, the physician who signs the form takes their share of responsibility that the issue or issues that the diver marked on the form have been sufficiently addressed.

From an administrative perspective, physicians providing telemedical care will need some way to electronically sign the form and send it back to the diver. In addition, we strongly recommend that these visits have an accompanying formal note recorded that outlines the topic(s) discussed, especially those related health issues that may affect diving safety. Lastly, while some topics may be amenable to telemedicine, others like heart and lung disease where you may want to perform an ECG, chest X-ray, or pulmonary function tests, would warrant in-person evaluation.

The question of diabetes and diving safety has long been of interest to the diving and diving medicine community. It is important to understand, though, that the relatively small amount of diving conducted by persons with diabetes means that the data collection is slow. This is reflected in the relative rarity of meetings to discuss guidelines. The 2005 joint Undersea and Hyperbaric Medical Society (UHMS) and Divers Alert Network (DAN) workshop was the seminal event to discuss meaningful empirical data.1,2 The 2020 South Pacific Underwater Medicine Society (SPUMS) diving medical guidelines are the latest update from that organization.3 Little has been published recently, mostly review or commentary on the incremental adoption or application of the existing guidelines.4-6 Neither the UHMS-DAN nor SPUMS guidelines are outdated, but the application and acceptance of them continues to evolve, both for medical evaluators and the diving community.

References

1. Pollock NW, Uguccioni DM, Dear GdeL, eds. Diabetes and recreational diving: guidelines for the future. Proceedings of the Undersea and Hyperbaric Medical Society/Divers Alert Network 2005 June 19 Workshop. Durham, NC: Divers Alert Network; 2005; 136 pp.

2. Pollock NW, Uguccioni DM, Dear GdeL. Diabetes and recreational diving: guidelines for the future. Diving Hyperb Med. 2006; 36(1): 29-34.

3. SPUMS Guidelines on Medical Risk Assessment for Recreational Diving. Victoria, Australia: South Pacific Underwater Medical Society; 2020; 34 pp.

4. Koufakis T, Karras SN, Mustafa OG, Karangelis D, Zebekakis P, Kotsa K. Into the deep blue sea: a review of the safety of recreational diving in people with diabetes mellitus, Eur J Sport Sci. 2019, doi: 10.1080/17461391.2019.1606286

5. Jendle J, Adolfsson P. Continuous glucose monitoring diving and diabetes: and update of the Swedish recommendations. J Diabetes Sci Technol. 2020; 14(1): 170-173. doi: 10.1177/1932296819826584

6. Jendle J, Adolfsson P, Pollock NW. Recreational diving in persons with type 1 and type 2 diabetes: advancing capabilities and recommendations. Diving Hyperb Med. 2020; 50(2): 135-43. doi: 10.28920/dhm50.2.135-143.

The participant screening process is intended to allow individuals with an extremely low level of perceived risk to bypass medical evaluation. When the potential for elevated risk is evident, medical evaluation is warranted to more fully ascertain individual circumstances and to open a dialogue to consider the pros and cons of participation. Learning and decision-making abilities are critical in diving to understand the risks - many of which are largely abstract - and to respond appropriately in times of need. The wording of the follow-up text in Box E is intentional:

"Been diagnosed with a mental health condition or a learning/developmental disorder that requires ongoing care or special accommodation."

Formal diagnosis warrants further investigation before participation in diving activity should be considered. This will best be accomplished through the collective efforts of personal medical monitors and clinicians familiar with diving medicine. The very practical goal is to ensure the capacity, understanding, and safety of all persons wishing to participate.

The participant questionnaire does capture protected information. If candidates are able to confirm "No" for all of the first 10 questions this signed form would be shared with whatever organization needs the declaration. The required disclosure is effectively one confirming no issues. If candidates confirm "Yes" for any of the first 10 questions and then "Yes" for any of the follow up questions medical evaluation and clearance is required. The examining physician would see all responses from the candidate and would learn additional confidential information during the evaluation, but the only documentation that has to be returned to the organization needing the declaration is the final "Physician's Evaluation Form" page. This includes the candidates name and birthdate and the medical decision ("Approved" or "Not Approved"). It contains no other protected health information. Neither the disclosures made in the medical questionnaire nor any other information disclosed to physicians need to be shared. Candidates may choose to share the internal pages, but the separation of the final page is intentional to protect patient confidentiality.

Our primary goals with the diving medical screening tools are to identify non-controversial elements to minimize the call for medical examination and to promote community understanding of medical health issues relating to diving. The challenge with hormone replacement therapy (HRT) is that it may be administered in a variety of formulations, and for a variety of reasons, and that in some cases it can be associated with an altered, and possibly increased, risk of coronary heart disease, stroke, deep vein thrombosis, and pulmonary embolism. Given the potential complexity of both prescription patterns and possible effects, medical consultation is appropriate to consider the treatments received and the implications for general and diving health.