What medical testing should Rebreather divers get?

fireman

I was a rescue diver for the fire department. Before we could get in the water we where required to pass a medical test. It consisted of: Background, stress test, hearing test, lung test(blow into a spirometer), a couple of things involving rubber gloves and KY, some x rays.

How about some expert opinions on extent and frequency for medical testing for Rebreather diving.

Also we swam hard at least twice a week. The test for surface rescue (lifeguard) requires 500 meters or 550 yards in 10 miniutes.

best wishes and stay safe.

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diverreb

I assume you are talking strictly voluntary stuff here.... Any activity with a degree of risk involves individual risk/reward choices, so to speak.

I for one am ready to hit 60 this year. I have certainly modified my diving habits & profiles to a large extent to reflect this. I am not what you would consider a well tuned physically fit individual.

I am aware that I'm at higher risk for a possible Cardiological Event due to age & physical condition. From what I've seen, I'm certainly not alone in this.

Being aware that I'm no longer super human, I won't dive in situations that are high stress. If the currents are running hard, I'll pay my dime & sit out the dive. I slow down or stop if I feel I'm over breathing. I'm not afraid to turn a dive if conditions change & I feel that it's becoming too challenging. With age comes wisdom...and less testosterone!

Even with that attitude, I realize that some things can get out of hand. If it does, it's my choice, my risk.

People generally know their own fitness levels. They don't need a Doctor & testing to let them know if they really should exercise more and eat better.

So if you really want to limit the risks or do more strenuous dives then get in shape & eat a better diet.

I know that if I want to continue diving at my current level that I have to do a better job of just that.

A few years back I was talking to my Cardiologist about some new imaging tests that would show blockages. He told me that even if it did, you can't infer that it will or won't cause an event. That if you are concerned about it, then change your lifestyle to reflect that it would. Great advice & easier said than done!

Hey.... why not a battery of mental tests. It seems that the statistics point to mental lapses rather than physical issues as a major cause of fatalities.

I would think that the physical tests are basically the standard tests we take to gauge our over-all health currently. Then what you choose to do or not do about it is on the individual.

Richie

scubanimal

I would recommend a blood test for CO2 retention, and a PFO test if you plan to do deep/deco Rebreather dives. Plus the usual stress tests for cardio etc.

For many folks Rebreather breathing is different, its much more relaxed and it is easy to get into a very calm relatively shallow breathing cycle; a bit like sitting watching tv. This can raise the CO2 being retained and if you naturally are a CO2 retainer this could pre-dispose you to CNS or Pulmanary toxicity.

PFO tests appear to be a very good idea prior to getting into deep diving.

After that, good health for any athletic sport is wise. I've seen recommendations that a mild workout before diving deep/extended is good.

Since I'm not an MD. My best recommendation is find a good MD who is into dive medicine and ask them. Maybe D Ebersole will speak up.

Shawn

Aside for your standard health screening I would recomend that you get tested for a PFO ( patent Foramen Ovale ).

Divers who dive deep and incur decompression are the ones who are most often affected by this. basically when you develope micro bubbles in the blood they can pass through the Ventral septum and cause an AI ( air Imbolism ) and death.

The test usually runs about $2000.00 if you can't get it covered by your insurance.

cramerdn

My wish list..

PFO check- My doc would'nt write the referal since I had no reason to think I had one. Of course the only thing that would make him give the referal was a DCS hit. A genius of the medical profession.

Some Test for CO2 Retention

Supervised controled hits of CO2, O2 tox, and Hypoxia

A good calabrated measure of RMV for rest, light effort, and heavy work

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fireman

Yes, Is there a test for CO2 retention?
I think Dave Sutton mentioned long ago that simulation of hypoxia, hypercampia, hyperoxia under controlled conditions would be a good idea. How about a CO2 hit on a tread mill.


Absolutely.
Voluntery--I'm just trying to encourage "us" to do it.
No old bold pilots, or Rebreather divers. Being aware of what you are doing and who you are key. But I think some people are in denial about how much risk they are taking, and what sort of shape they are in.

Mental tests--Isn't that what training is for. Or thats what rebreather diving is, a mental and physiological test.

Regarding the imaging, I still think the stress test is the way to go. (laymans opinion)

__________________
Heres to you Capt. Bill
Never Forget, and stay safe everyone.

Dsix36

Why do I feel like this was directed at me

Some of us might have trouble passing these tests.

Just sayin


.

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THE MORE THAT I LEARN, THE MORE THAT I STILL NEED TO LEARN!!!!!!

diverreb

No problem Don.... just take some waterproof crib sheets down with you & study them passing the time away while you're stuck in the various wrecks!

Richie

Gene_Hobbs

Thought you all might enjoy reading through these reviews:

Southerland DG. Medical Fitness at 300 FSW. In: Lang, MA and Smith, NE (eds.). Proceedings of Advanced Scientific Diving Workshop: February 23-24, 2006, Smithsonian Institution, Washington, DC. RRR ID 4659

Ma, AC and Pollock, NW. Physical Fitness of Scientific Divers: Standards and Shortcomings. NW Pollock and JM Godfrey (Eds.) The Diving for Science…2007, Proceedings of the American Academy of Underwater Sciences (AAUS), Twenty-sixth annual Scientific Diving Symposium, University of Miami, Miami, FL. RRR ID 6991

As for CO2 retention... There seems to be quite a bit of variability but these papers are interesting:

Eynan M, Daskalovic YI, Arieli Y, Arieli R, Shupak A, Eilender E, Kerem DH. Training improves divers' ability to detect increased CO2. Aviat Space Environ Med. 2003 May;74(5):537-45. PubMed ID: 12751583

Kerem, D; Daskalovic, Y; Arieli, R; Shupak, A. CO2 retention during hyperbaric exercise while breathing 40/60 nitrox. Undersea Hyperb Med. 1995 Dec;22(4):339-46. RRR ID: 2202

Kerem, D; Melamed, Y; Moran, A. Alveolar Pco2 during rest and exercise in divers and non-divers breathing O2 at 1 ATA. Undersea Biomed Res. 1980 Mar;7(1):17-26. RRR ID: 2876

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Simon Mitchell

Hello,

I think you are being unfair on your doctor whose stance is more sensible than you think. However, like most doctors who have not had extensive experience and training in diving medicine, he / she is probably not equipped to logically explore the issue of PFO screening with you. This hoary old chestnut has been debated ad infinitum on forums like this. I do not intend rehashing it all here but two points are germaine to the present discussion.

First, the overwhelming weight of medical opinion is that PFO screening is not appropriate for all divers entering the sport (that is, enrolling for open water courses).

Second, and notwithstanding the first, there is debate over whether screening is better justified in divers regularly undertaking more provocative dives (such as yourself), and this remains one of the most controversial issues in diving medicine today.

I have no problem with technical divers opting to be screened, but only after counselling about the implications of the process they are embarking on. Once you have been screened (and there is a 30% chance a PFO will be found) then the genie is out of the bottle and you can't put it back. Some difficult interpretations and decisions then have to made. Mike Bennett and I have written reasonably comprehensively on this in our recent chapter on fitness for diving in Neuman and Thom's "Physiology and Medicine of Hyperbaric Oxygen Therapy".

There is no blood test that indicates a tendency to carbon dioxide retention in healthy divers. Nor is there any way of easily or reliably testing that tendency by other means. I'm not saying that carbon dioxide retention cannot be experimentally identified, but pragmatically speaking, it cannot be offered to recreational divers as a valid screening test.

Warm regards,

Simon M