I find the decision that recommendations are made purely on the understanding of physiology and pathophysiology to be a little disconcerting, as the history of medicine is littered with things we thought would work (or were dangerous) had bioplausability, but turned out to be dead wrong.
As I noted earlier, CT scans have noted small amounts of air trapping in some otherwise perfectly healthy appearing individuals. It would stand to reason that some divers likely have this finding and continue to apparently dive safely.
None the less I will acknowledge that data generation in this one specific space would be difficult to say the least. I also do not know how many people we are talking about - the number of divers who appear healthy but due to prior injury/surgery/illness there is some desire to screen them for diving. Is there enough demand to justify the resources spent in this population? I agree that anyone involved would love more data to hang their hat on when making these decisions. I do think it is imporntant that our patients are aware that when these evaluations are being performed we often do not have any solid data one way or the other when deciding if someone is fit or unfit to dive once we get away from the margins (obviously healthy or obviously unfit)
I will argue that saying the lack of a clearance to dive does not prevent someone from diving is not always true. Certainly there are professional divers who if not cleared would not be permitted to continue to work. I would argue that significant evidence should be needed to end someone’s career. I would also argue that the risk of downstream problems related decision to not clear a professional diver (loss of income, possible depression/substance abuse, loss of insurance, personal relationship strain, etc) should be considered together with the risk of diving, as one risk may outweigh the other.
Additionally even recreational divers may have issues if that diver needs the assistance of a dive shop for rentals or guides and the shop wants a physician note for one reason or another. Or perhaps a spouse who insists on a “clean bill of health” to dive. Perhaps their insurance coverage requires a fitness to dive exam. Any of these reasons may find a recreational diver now land locked with a failed medical.
I do thank you for sharing that generally the dive physician community looks for reasons someone should be allowed to continue diving vs looking for reasons to disqualify someone, but I would still find it more reassuring if all of the decisions (either yes or no) had better evidence beyond expert opinion based on bioplausible theories. Although I will also acknowledge this issue is in no way limited to dive medicine alone.
As to the discussion about incidental findings - I do not use the risk of unanticipated findings as a sole reason to not run a study, but I do believe it is something that should be considered; IE how informative is this study going to be for the clinical question that I want the study for vs the cost/time/risk of the study itself (radiation, injury, etc) vs what do I do with any incendential findings that pop up.
Over the last decade or so there has been much more research and talk about the increasing rates of incidental findings as imaging as gotten more detailed and prevalent. There is at least an ongoing conversation that more harm rather than good is being done.
“Incidental imaging findings are common and analogous to the results of screening tests when screening is performed of unselected, low-risk patients. Approximately 15–30% of all diagnostic imaging and 20–40% of CT examinations contain at least one incidental finding. Patients with incidental findings but low risk for disease are likely to experience length bias, lead-time bias, overdiagnosis, and overtreatment that create an illusion of benefit while conferring harm.”
“In an analysis of medical records gathered from more than 300 hospitalized patients, a team of researchers reports that routine imaging scans used to help diagnose heart attacks generated “incidental findings” (IFs) in more than half of these patients.
The investigators say only about 7 percent of these IFs were medically significant and urged imaging experts and hospitals to explore ways to safely reduce the added costly — and potentially risky — days in the hospital the IFs generate.”
“As practitioners increasingly rely on cross-sectional imaging, they are faced with a rising burden of incidental findings. In a retrospectively identified, contemporary cohort of patients who underwent 1426 imaging studies in the setting of clinical research, 567 (39.8%) had a minimum of one incidental finding.<a href="
The Economic Burden of Incidentally Detected Findings - PMC">19</a> Further work-up definitively benefitted patients in 6 cases (1.1%) in which significant infections or neoplasms were identified.<a href="
The Economic Burden of Incidentally Detected Findings - PMC">19</a> While incidental findings occasionally present an opportunity to cure or halt an otherwise lethal disease, many downstream consequences are negative. For patients, they can create anxiety and additional work-up for findings which are ultimately benign or unlikely to affect their life expectancy. For busy practitioners, the recommended follow-up can be difficult to organize, and can detract care from more important medical issues. Furthermore, these consequences can translate into substantial downstream expenditures.”
pmc.ncbi.nlm.nih.gov
