Diving too carefully?

[X181]

From a readers point of view Simon is the only one making any sense in this. You just keep ducking for questions rossh, and Simon keeps coming up with articles and facts to prove what he says.

Lol facts like DCS of people with a BMI of 34 and full of drugs? Ok its a fact, but a not relevant and absolutely unuseful one. Bring me facts of undeserved type 2 of fit divers, RL tested, hydrated, rested, none smokers, etc. Honestly the rest im not interested in.

Simon argumented that its cheaper to treat hits than check the divers! Ok if the next chamber is operating and near and not in use and and and.

Im not the NHS i dont care for the overall costs to prevent or treat a DCI hit. I care only for my team.

 

[Simon Mitchell]

Lol facts like DCS of people with a BMI of 34 and full of drugs? Ok its a fact, but a not relevant and absolutely unuseful one.

The point of raising the case was that Ross refused to believe that cardiopulmonary DCS could occur early after a normal properly conducted ascent. The case proves that it can. If you believe that it is irrelevant because the diver was overweight and treated for high blood pressure then you are sorely out of touch with the demographics of the global diving scene (especially rebreather diving).

Bring me facts of undeserved type 2 of fit divers, RL tested, hydrated, rested, none smokers, etc. Honestly the rest im not interested in.

I can assure you that I have treated many such cases. One of the contemporary hypotheses to explain some of these cases is that VGE may have crossed pulmonary shunts which are not excluded by PFO tests.

Simon argumented that its cheaper to treat hits than check the divers!

That is a fact, and it was a direct response to Ross's claim that "the test is cheaper than the treatment". At least partly because of economic considerations and in recognition of the principles of sensible screening, 2 days ago the UHMS PFO consensus workshop at Montreal attended by over 100 diving physicians (including most of the world's leaders) unanimously endorsed the SPUMS / UKSDMC statement:

Routine screening for patent foramen ovale (PFO) at the time of dive medical fitness assessment (either initial or periodic) is not indicated.

The full SPUMS / UKSDMC statement can be found at:

SMART D, MITCHELL SJ, WILMSHURST P, TURNER M, BANHAM N. Joint position statement on persistent (patent) foramen ovale and diving. South Pacific Underwater Medicine Society (SPUMS) and the United Kingdom Sports Diving Medical Committee (UKSDMC). Diving Hyperbaric Med. 2015:45:129-131

I would also like to point out that I did not say no diver should ever be tested. I summarised my views on this in an earlier post. It is a different (and more complex) issue to the one we have been debating (the importance of VGE), and if you would like to discuss it in a different thread I would be glad to.

Simon M

 

[michael_fisch]

I had a bad Type 2 hit back in september 2014 at the age of 57. Tested with TEE and TCD back in 2013 > no shunts. Happened after 2nd dive on day4 after 4 days of 2 mixed gas deco dives a day. min O2 deco each dive greater than 30 minutes. Minimum pause between dives was 3 hrs. GF High set at 90% on a OSTC2 (which has an additional safety factor of 10% built in in addition to the GF settings).
was successfully treated in the 2nd hospital with a TT6 incl 3 extensions, a TT5 4 hrs later and 2 further chamber treatments at 2.4Bar O2 to clean up lingering problems.

Important Advise!! Don't get on the helicopter alone, if you do you will get whatever the doctors, who have never heard about DCS, decide to give you, and nobody in a hospital ever takes advice from a patient. Have your buddy who accompanies you to a hospital be armed, locked and loaded, at least that way somebody is going to have to listen.
I was alone, very sick and it took the IC doctors in the first hospital 5 hrs to finally decide that O2 at 1lpm and an IV Drip just fast enough to keep the lines from clogging wasn't doing me a lot of good. the 2nd helicopter ride was much better and my litter was on the move being run, while the wheels were still settling, by 6 people right into the chamber. 2 minutes after landing I was at 2.8Bar on O2 and starting to feel again. Due to all the tissue damage I gained 20lbs before I started peeing again, and it took almost a month to lose all the extra fluids in my damaged cells.
BMI 27, age 57, nonsmoker since Dec 1999, active diver - 100+ Deco Dives a year for over 20 years, in reasonably good shape, lownormal cholestoral levels, good heart, no circulation problems - just age over 50! Old folks can't decompress as quickly as 20 year old navy seals who don't have a PFO. Now I dive a rebreather, GF High is 80% max, and I no longer do 2 deco dives a day for more than 3 1/2 days before restarting the schedule (means on a 8 day dive trip, I'll do 14 deco dives instead of my buddies 16 deco dives). Getting old is hell, but it is still better than not getting any older.

Michael

 

[X181]

The point of raising the case was that Ross refused to believe that cardiopulmonary DCS could occur early after a normal properly conducted ascent. The case proves that it can. If you believe that it is irrelevant because the diver was overweight and treated for high blood pressure then you are sorely out of touch with the demographics of the global diving scene (especially rebreather diving).



I can assure you that I have treated many such cases. One of the contemporary hypotheses to explain some of these cases is that VGE may have crossed pulmonary shunts which are not excluded by PFO tests.



That is a fact, and it was a direct response to Ross's claim that "the test is cheaper than the treatment". At least partly because of economic considerations and in recognition of the principles of sensible screening, 2 days ago the UHMS PFO consensus workshop at Montreal attended by over 100 diving physicians (including most of the world's leaders) unanimously endorsed the SPUMS / UKSDMC statement:

Routine screening for patent foramen ovale (PFO) at the time of dive medical fitness assessment (either initial or periodic) is not indicated.

The full SPUMS / UKSDMC statement can be found at:

SMART D, MITCHELL SJ, WILMSHURST P, TURNER M, BANHAM N. Joint position statement on persistent (patent) foramen ovale and diving. South Pacific Underwater Medicine Society (SPUMS) and the United Kingdom Sports Diving Medical Committee (UKSDMC). Diving Hyperbaric Med. 2015:45:129-131

I would also like to point out that I did not say no diver should ever be tested. I summarised my views on this in an earlier post. It is a different (and more complex) issue to the one we have been debating (the importance of VGE), and if you would like to discuss it in a different thread I would be glad to.

Simon M

As far as i know RL test cover also pulmonary shunts at the time of the test. I'm aware that new ones may build later.

What i don't get is where you want to draw the line. Every model works in certain bounderies. If i got you right you want to cover BMI 34 under drug intake because that is what people do, even if they know that they violate the bounderies of the model. At a certain point every model will fail. There are so many things to see in the shallow water, why do they risk their lifes?

If we lift the level again people will break also the new level because they are now 65 with a BMI of 40! In other sports the limits are very clear. In diving people tend to ignore the reality and that they should change their behaviour if they get older and less fit.

 

[Simon Mitchell]

As far as i know RL test cover also pulmonary shunts at the time of the test.

Unfortunately not.

Occasionally there is evidence for right to left shunting of VGE across the lungs during a PFO test when right heart bubbles appear in the left heart after a delay. Also, if you are skilled with transesophageal echo you can image the pulmonary veins entering the left atrium, and it is possible to see bubbles exiting them. However, the big problem with pulmonary shunts is that they usually don't become apparent until the subject exercises. This has been demonstrated multiple times by Marlowe Eldridge's team who have published extensively on the subject. Marlowe was also at the UHMS PFO meeting 2 days ago and talked about this. One of his recent publications on the subject is:

Lovering AT et al. Transpulmonary passage of 99m Tc microaggregated albumin in healthy humans at rest and during maximal exercise. J Appl Physiol 2009;106:1986-92.

Normal PFO tests don't include exercise, and it would be very difficult to do this. Thus, normal PFO tests do not reliably cover pulmonary shunts unfortunately.

What i don't get is where you want to draw the line. Every model works in certain bounderies. If i got you right you want to cover BMI 34 under drug intake because that is what people do, even if they know that they violate the bounderies of the model. At a certain point every model will fail. There are so many things to see in the shallow water, why do they risk their lifes?

I understand why you would ask that question, but divers make individual risk decisions and I cannot answer it for them. I don't consider it ideal, but nor do I think there is anything particularly unusual about an overweight diver with treated hypertension. They are part of the diving world. I don't want to make this about specific models necessarily; that argument has been had many times. This debate has been about the significance of VGE. If we can finally accept that high VGE grades are associated with higher risk, and if (as Mark pointed out) there were differences between approaches to decompression such that one approach produces more high VGE grade events than another despite the dives being of equal length, then that would be an important finding for divers contemplating which approach to use, irrespective of their state of health.

Simon M

 

[X181]

I had a bad Type 2 hit back in september 2014 at the age of 57. Tested with TEE and TCD back in 2013 > no shunts. Happened after 2nd dive on day4 after 4 days of 2 mixed gas deco dives a day. min O2 deco each dive greater than 30 minutes. Minimum pause between dives was 3 hrs. GF High set at 90% on a OSTC2 (which has an additional safety factor of 10% built in in addition to the GF settings).
was successfully treated in the 2nd hospital with a TT6 incl 3 extensions, a TT5 4 hrs later and 2 further chamber treatments at 2.4Bar O2 to clean up lingering problems.

Important Advise!! Don't get on the helicopter alone, if you do you will get whatever the doctors, who have never heard about DCS, decide to give you, and nobody in a hospital ever takes advice from a patient. Have your buddy who accompanies you to a hospital be armed, locked and loaded, at least that way somebody is going to have to listen.
I was alone, very sick and it took the IC doctors in the first hospital 5 hrs to finally decide that O2 at 1lpm and an IV Drip just fast enough to keep the lines from clogging wasn't doing me a lot of good. the 2nd helicopter ride was much better and my litter was on the move being run, while the wheels were still settling, by 6 people right into the chamber. 2 minutes after landing I was at 2.8Bar on O2 and starting to feel again. Due to all the tissue damage I gained 20lbs before I started peeing again, and it took almost a month to lose all the extra fluids in my damaged cells.
BMI 27, age 57, nonsmoker since Dec 1999, active diver - 100+ Deco Dives a year for over 20 years, in reasonably good shape, lownormal cholestoral levels, good heart, no circulation problems - just age over 50! Old folks can't decompress as quickly as 20 year old navy seals who don't have a PFO. Now I dive a rebreather, GF High is 80% max, and I no longer do 2 deco dives a day for more than 3 1/2 days before restarting the schedule (means on a 8 day dive trip, I'll do 14 deco dives instead of my buddies 16 deco dives). Getting old is hell, but it is still better than not getting any older.

Michael

For me very interesting, despite of several risk factors. If it was really out of the blue this looks for me as a undeserved type 2.

 

[tripntx]

I had a bad Type 2 hit back in september 2014 at the age of 57. Tested with TEE and TCD back in 2013 > no shunts. Happened after 2nd dive on day4 after 4 days of 2 mixed gas deco dives a day. min O2 deco each dive greater than 30 minutes. Minimum pause between dives was 3 hrs. GF High set at 90% on a OSTC2 (which has an additional safety factor of 10% built in in addition to the GF settings).
was successfully treated in the 2nd hospital with a TT6 incl 3 extensions, a TT5 4 hrs later and 2 further chamber treatments at 2.4Bar O2 to clean up lingering problems.

Important Advise!! Don't get on the helicopter alone, if you do you will get whatever the doctors, who have never heard about DCS, decide to give you, and nobody in a hospital ever takes advice from a patient. Have your buddy who accompanies you to a hospital be armed, locked and loaded, at least that way somebody is going to have to listen.
I was alone, very sick and it took the IC doctors in the first hospital 5 hrs to finally decide that O2 at 1lpm and an IV Drip just fast enough to keep the lines from clogging wasn't doing me a lot of good. the 2nd helicopter ride was much better and my litter was on the move being run, while the wheels were still settling, by 6 people right into the chamber. 2 minutes after landing I was at 2.8Bar on O2 and starting to feel again. Due to all the tissue damage I gained 20lbs before I started peeing again, and it took almost a month to lose all the extra fluids in my damaged cells.
BMI 27, age 57, nonsmoker since Dec 1999, active diver - 100+ Deco Dives a year for over 20 years, in reasonably good shape, lownormal cholestoral levels, good heart, no circulation problems - just age over 50! Old folks can't decompress as quickly as 20 year old navy seals who don't have a PFO. Now I dive a rebreather, GF High is 80% max, and I no longer do 2 deco dives a day for more than 3 1/2 days before restarting the schedule (means on a 8 day dive trip, I'll do 14 deco dives instead of my buddies 16 deco dives). Getting old is hell, but it is still better than not getting any older.

Michael

Thanks for sharing. What was your low GF setting then and what do you set it at now?

 

[Captain Starfish]

...Simon engages in slurs, slander, libel, innuendo, baseless accusations, irrelevant criticism, groundless denunciations, semantics, and on and on its goes.

But he doesn't act like a two year old throwing a tantrum because he isn't getting his own way.

Well done, Ross. I've been taught to "play the ball, not the man" but I'll admit I'm not very good at it. It saddens me that I'm small enough of a man that it's only a small part the science but mostly on the basis of your performances on these forums, I will never use VPM or any variation of it. Because what I see is a model that's had some doubt cast over its validity and the champion of that model is the mad monk screaming "Heresy!" anytime anyone is mean about it.

I already have one mad monk running our Australian government and country into the ground as fast as he can. There's no way I'm handing my life over to another one.

Perhaps you should look up Brad Horn and start a sub-forum on the do's and don'ts of interacting with other people in a public forum.

 

[silentbob]

The Dunning Kruger effect. :0)

The Dunning Kruger effect is a cognitive bias wherein unskilled individuals suffer from illusory superiority, mistakenly assessing their ability to be much higher than is accurate. This bias is attributed to a metacognitive inability of the unskilled to recognize their ineptitude.

 

[michael_fisch]

GF Low was and is 45%. But I ascend from depth slowly anyway at a rate of 6-7M / minute. This means that my first couple of 1 minute stops disappear before I get to the stop depth. Gas switchs are always at least 5 minute stops in order to allow the blood to travel twice through my circulatory system with the new gas before ascending further. This often means that after the gas switch at 21M, my next 1 or 2 stops are no longer necessary.
15-20 years ago I was using GF High at 125% w/o any problems, trying to use GF High at 150% (as Buchaly and Waldbrenner were using) didn't work out well, I'd be really exausted for 5-8 hours after a dive, no such symptoms using 125% though. As I got older I started to lose the ability to handle high GF Highs well, and finally ended up using 90% with an extremely slow ascent from my last stop at 6M. Now I'm doing the same using a GF High of 80% on multiday repetive dive trips. What screwed me up in september was the 2 deco dives a day for 4 days in a row coupled with fast ascent from 6M, excertion geting back on the boat, and then transferring all the gear from the boat to the dive base 45 minutes after the dive, coupled with my age.
10 minutes after I started feeling that something wasn't right I fell down while breathing O2 and was unable to get up onto my hands and knees. Totally marbled skin from the neck down, breathing problems, inability to touch my nose with my fingertips irrespective of weather my eyes were open or closed, loss of ability to pee, and I think that I also had visual disturbances, since I wasn't able to see the letters on all the papers that need signing. Thank God the chamber doctor really knew her shit, by the time I got into the chamber the window of opportunity had long closed, and I was sure that, at best, I'd be using a walker for the rest of my life. I was wrong, she was right, and she extended the TT6 enough to make sure that she was right. and followed it up 4 hours later with a TT5, giving the rest of the hospital a 4 hour window to examine me before the 2nd chamber ride. Never before in my life have I had department heads lined up in order to examine me.

Michael

Michael

 

[rossh]

This was classical cardiopulmonary DCS that occurred because of massive VGE formation. It is a well recognised (though thankfully rare) manifestation of DCS that typically onsets early after a dive.


The point of raising the case was that Ross refused to believe that cardiopulmonary DCS could occur early after a normal properly conducted ascent. The case proves that it can. If you believe that it is irrelevant because the diver was overweight and treated for high blood pressure then you are sorely out of touch with the demographics of the global diving scene (especially rebreather diving).

Simon M

Your characterization of my beliefs, is invalid and deliberately derogatory... again.

I already described two "chokes" examples - SurD, and emergency ascent. Also add pre/post dive exercise on extreme dives.

***************



Simon wrote: "The case proves that it can."


Proof... ha. You mean your opinion overruled another doctor's different opinion. The second opinion I asked for, excluding your own, suggested other causes.


Tell us Simon where did this "massive VGE" you describe come from? His dive profile was a relatively small beginner level deco dive, with a relatively small total gas load.

He didn't do a SurD deco or emergency ascent here. He doesn't have a massive gas load to create VGE from, or have any unusual or extreme post dive activity. Even if he did a SurD procedure, he would still have many minutes before the cardiopulmonary DCS symptoms appear. He did his normal deco and climbed the ladder, just like a millions others have done.


But this man was immobile within minutes of surfacing and died shortly after that, but He didn't have the total gas load within him, or the procedure failures, or enough time, to get the injury you claim.

 

[Simon Mitchell]

Proof... ha. You mean your opinion overruled another doctor's different opinion. The second opinion I asked for, excluding your own, suggested other causes.

Drs Edmonds, Gorman, Fock and Mitchell believed it was cardiopulmonary DCS arising from massive formation of VGE. Not a single one of the diving medicine experts involved in the case dissented with this view. The pathologist who did not have training in diving medicine and did the autopsy (and found gas everywhere as you do following a fatality early after a dive) initially said arterial gas embolism, but immediately changed his opinion when he heard evidence from the diving medicine experts. You could learn from his example.

Tell us Simon where did this "massive VGE" you describe come from? His dive profile was a relatively small beginner level deco dive, with a relatively small total gas load.

It was actually the 4th deco dive over a 2 day period.

Not for the first time you are revealing your ignorance of both the literature and the clinical diving medicine field. This sort of event caused by early bubble formation is well recognised. It may not fit your preconceptions but you just have to get over that and learn from it.

I have already provided you with a reference demonstrating VGE from the point of surfacing in short bounce dives. Who knows why the bubble formation was greater after this dive than others. The fact is that it can happen.

Now, since you believe VGE are harmless, can you explain why DCIEM rejected profiles producing VGE greater than grade 2 on more than 50% of occasions???

Simon M

 

[rossh]

Now, since you believe ...... (I'm telling you what you think)

Simon M

There it is again.... You change and frame my position in a way that suits you, so you can make easy arguments against it.


Why do you keep doing these antagonistic and diversionary switch and bait tactics? I think you are trying to bully anyone out of your way, because you can't stand it when other people have opinions that do not agree with yours.

We saw this kind of behavior from you towards your peers on these forums a few years ago. Anytime one wrote a different view point to yours, you would viciously attack them, until they give up and left.


**********

... can you explain why DCIEM rejected profiles ...
Simon M

Yes.


But I would prefer that people read the report by the DCIEM that explains all this in full context. The link is here: download

Because your simplistic interpretation of the reasons Simon, is well... not accurate.




*************

It was actually the 4th deco dive over a 2 day period.

Simon M

He had a 4 hour surface interval. The math says his tissue pressure levels before the last were low. If he used ZHL-C, he would have needed a only a few extra minutes of deco time.

His surfacing pressures were around 800 mb + tissue gradient, with 550mb supersaturation. These are typical of every dive by anyone. His supersaturation had diminished to 0 at 2 hours after the last dive - also typical of all dives.

VGE peaks at about 90 mins after a dive and is insignificant to non existent after 4 hours.


More relevant, his dive, profile and repeats, are typical of everyday diving done the world over. Yet this divers death appears to be atypical.


So I ask again Simon, Where did this VGE come from? The model math does not support massive VGE, and the everyday experience of divers shows they do not suffer this sudden death problem.


I'm asking because I want you to explain. Please do not wave your arms around again and try to dismiss me and the question.

 

[Simon Mitchell]

There it is again.... You change and frame my position in a way that suits you, so you can make easy arguments against it.

Your "belief" about VGE has been made abundantly clear by..... you:

"Post 99: High VGE is not a bad thing. It says you have an abundance of gas leaving the tissues and heading to the lung to be exhaled - that is of course exactly what is supposed to happen in decompression."

"Post 95: As I discussed above, VGE is not a good measure and adds nothing to DCS avoidance. VGE has been ignored for these reasons for 40+ years since Spencer found then in the early 70's. No new information is available by watching VGE, so they should be ignored."

Except that DCIEM who you have lauded in the past, didn't ignore them in testing and choosing their schedules, nor did any scientist conducting decompression research since the 1970s, and nor did any of the major chapters on DCS pathophysiology in any of the current texts. Guess they / we are all wrong because you say so.

And by the way...

"ignored for these reasons for 40+ years since Spencer found them in the early 70s" ??

Perhaps you should read this paper:

Spencer MP. Decompression limits for compressed air determined by ultrasonically detected blood bubbles. Journal of Applied Physiology 1976;40(2)229-35.

Guess he must have started ignoring them after he wrote that paper.

Because your simplistic interpretation of the reasons Simon, is well... not accurate.

Well, that "simplistic interpretation" was straight out of the mouth of the test program director and former DCIEM chief scientist two days ago. But I guess he's wrong too.

So I ask again Simon, Where did this VGE come from? The model math does not support massive VGE, and the everyday experience of divers shows they do not suffer this sudden death problem.

I'm really sorry that real world pathophysiology doesn't always conform with model math. I guess the model math must be right.

I'm asking because I want you to explain. Please do not wave your arms around again and try to dismiss me and the question.

Didn't you say this a few pages back??

"VGE volumes are highly irregular - with a 50% variance between individuals. VGE amounts can be altered drastically by pre-dive activity like warming the diver, and vibration"

One of the few accurate things you've said on this thread. There's your answer Ross. Sometimes it just happens and we don't have a good explanation for it.

Cardiopulmonary DCS is just a tangible (but thankfully rare) example of VGE being bad. This rarity makes a protracted debate over it somewhat pointless. The much more common and important issue with VGE is their potential shunting from the venous to arterial circulations, and the association of that with inner ear, spinal, cerebral, and cutaneous DCS.

Simon M

 

[Mark Chase]

But I would prefer that people read the report by the DCIEM that explains all this in full context. The link is here: download

Ross i just speed read this document and focused on what i felt were the critical parts and all I found was referance to the use of Dopler testing to validate the model

Dopler testing is how they check VGE is it not?

Could you refer me to the page where theres something that suports your argument

ATB

Mark

 

[Ben Field]

I had a bad Type 2 hit back in september 2014 at the age of 57. Tested with TEE and TCD back in 2013 > no shunts. Happened after 2nd dive on day4 after 4 days of 2 mixed gas deco dives a day. min O2 deco each dive greater than 30 minutes. Minimum pause between dives was 3 hrs. GF High set at 90% on a OSTC2 (which has an additional safety factor of 10% built in in addition to the GF settings).

HI Micheal, glad to hear you received good treatment in the end, I hope you made a complete recovery?

Several posters below your OP seem to think this was "undeserved" but (no offense intended) the description above is what I would describe as Provocative... Multiple deco dives on mixed gas and short intervals using deco based on deco based on animal testing intended to generate algorithms for 20yr old fit navy divers with minimal safety thresholds is aggressive

10-15yrs ago most people rarely did back to back deco dives, or the second was at least alot shallower and even took days off on longer trips to "reset the clock" with modern computers people are doing back to back mixed gas dives because the math appears to allow it. The fact is the math in an OSTC2 (and all other computers) is essentially guessimations on top of very old data.

Your bend wasn't undeserved, it was unlucky perhaps.

Every time anyone dives we risk a bend, the art/luck/science is to surface at 99% or less the threshold of clinical symptoms, our tables and decompression computers have a level of accuracy we could probably measure in only minutes for certain individuals, you only have to stray slightly into these grey areas to take a chance.

Your story is a good cautionary one though- the recovery should stand as an example of what can happen with ease and we all need to be mindful of that.

 

[tripntx]

GF Low was and is 45%. But I ascend from depth slowly anyway at a rate of 6-7M / minute. This means that my first couple of 1 minute stops disappear before I get to the stop depth. Gas switchs are always at least 5 minute stops in order to allow the blood to travel twice through my circulatory system with the new gas before ascending further. This often means that after the gas switch at 21M, my next 1 or 2 stops are no longer necessary.
15-20 years ago I was using GF High at 125% w/o any problems, trying to use GF High at 150% (as Buchaly and Waldbrenner were using) didn't work out well, I'd be really exausted for 5-8 hours after a dive, no such symptoms using 125% though. As I got older I started to lose the ability to handle high GF Highs well, and finally ended up using 90% with an extremely slow ascent from my last stop at 6M. Now I'm doing the same using a GF High of 80% on multiday repetive dive trips. What screwed me up in september was the 2 deco dives a day for 4 days in a row coupled with fast ascent from 6M, excertion geting back on the boat, and then transferring all the gear from the boat to the dive base 45 minutes after the dive, coupled with my age.
10 minutes after I started feeling that something wasn't right I fell down while breathing O2 and was unable to get up onto my hands and knees. Totally marbled skin from the neck down, breathing problems, inability to touch my nose with my fingertips irrespective of weather my eyes were open or closed, loss of ability to pee, and I think that I also had visual disturbances, since I wasn't able to see the letters on all the papers that need signing. Thank God the chamber doctor really knew her shit, by the time I got into the chamber the window of opportunity had long closed, and I was sure that, at best, I'd be using a walker for the rest of my life. I was wrong, she was right, and she extended the TT6 enough to make sure that she was right. and followed it up 4 hours later with a TT5, giving the rest of the hospital a 4 hour window to examine me before the 2nd chamber ride. Never before in my life have I had department heads lined up in order to examine me.

Michael

Michael

Thank you. While I like 55 to be the minimum low number and prefer 70, I might settle on something in-between them. Although I frequently change my high number between 80-90 on a regular basis. Might use 65/85 for this summer.
Just for stats: my age upper 40's, BMI 29, currently doing cardio 30 minutes a day to get BMI back into lower 20's. Non-smoker, and seldom drink. My BMI had crept up to 31, and it was driving me crazy. Spent first 20 yrs of adult life in USAF so I was required to maintain a healthy BMI. I can tell you, BMI above 25 makes you sluggish and my lower back starts hurting with it near 30.

I do not want to have my deco profile restricted or altered due to the people with PFO. That's like saying we need to ban alcohol or vehicles because people cause deaths by drinking and driving.

 

[Ben Field]

I do not want to have my deco profile restricted or altered due to the people with PFO. That's like saying we need to ban alcohol or vehicles because people cause deaths by drinking and driving.

Pretty sure no one is suggesting that here!

 

[michael_fisch]

That's like saying we need to ban alcohol or vehicles because people cause deaths by drinking and driving.

Can't agree with that. Assuming that 20% of accidents are caused by drunk drivers, if you eliminated drunk drivers you would still only reduce the total number of accidents by 20%.
Getting rid of sober drivers would make the roads much safer since that would eliminate the 80% caused by sober drivers.:drink:

BTW, my hit was not undeserved, I was provoking my body past it's limits. Although 5 years earlier I would not have had a problem, at my age (now 58) I had a serious problem. The combination of 8 deco dives within 100hrs actually 77hrs, minimal deco at GF90, excertion climbing a boat ladder, no post dive hydration, transporting dive gear 45 minutes after surfacing, and my age were too much for my body to handle.


Michael

 

[rossh]

Cardiopulmonary DCS is just a tangible (but thankfully rare) example of VGE being bad. This rarity makes a protracted debate over it somewhat pointless. The much more common and important issue with VGE is their potential shunting from the venous to arterial circulations, and the association of that with inner ear, spinal, cerebral, and cutaneous DCS.

Simon M

So you failed to answer the pertinent question - where did this "massive VGE" come from? The man did not have the total gas load to produce this. He did a normal ascent. The dive profile and repeat pattern is common in diving. But this man experienced a deviation - orders of magnitude greater than normal - that you say killed him shortly surfacing. It seems your VGE explanation does not stand up to analysis.

Of course, I am asking for the impossible - a doctor to correct his mistaken opinion.


*********

Well I thought about your earlier question: "why DCIEM rejected profiles producing VGE greater than grade 2 on more than 50% of occasions"

The answer is they wanted everyone to enjoy the pleasures of VGE. By using a level 2, and with the 50% variance between individuals, it means that over 90% of all divers can benefit from VGE coursing through their system, accumulating in their lungs, and making little blips on doppler screens everywhere. Almost no one is left out. Wasn't that thoughtful of them.