Are Rebreathers Safer for DCI prone divers than OC

hchoat · 9th January 2006, 20:56

While you give us some idea of your background, you don't provide us with information regarding profiles, gasses, etc. I would suggest to you that 2 minor "hits" in 500 plus dives for a very active diver is not unreasonable. Bear in mind that DCI is a sports injury. There are NO guarantees that you won't take a "hit" on any given dive for no perceptible reason. I would be far more concerned with your hydration level, fatigue level, etc. at this point than saying you are "prone" to DCI.

Heather

wizbang · 9th January 2006, 22:19

Quote: (Originally Posted by hchoat)

While you give us some idea of your background, you don't provide us with information regarding profiles, gasses, etc. I would suggest to you that 2 minor "hits" in 500 plus dives for a very active diver is not unreasonable. Bear in mind that DCI is a sports injury. Heather

I have had no hits in 2200 odd dives (not an instructor).
Certainly 2 in 500 would have made me think twice about my chosen sport.

A sports injury? An injury aquired while playing sport. Sure
A twisted/sprained ankle in Netball / football is my definition of sports injury.
A broken neck from football also fits the definition but is certainly at the extreme end.

Quote:

There are NO guarantees that you won't take a "hit" on any given dive for no perceptible reason. I would be far more concerned with your hydration level, fatigue level, etc. at this point than saying you are "prone" to DCI.

I agree.
IMHO Deco Theory is pseudoscience. Best guess by some smart people is how I look at it.
I do think some people are more "prone" than others. (ie std distribution curve) but the factors you mention can make it better or worse depending on how you look after yourself.

Def · 9th January 2006, 22:48

Gday Shellback,

To Answer your questions, I will quote them as B1 and B2 (bend 1 and Bend 2)

>What was the temp of the water of said hits?
B1 - 18-19d water temp, 23-24d Air Temp, Diving in a Dry Suit...
B2 - 27-29d water temp, 29-34d Air Temp, in a 3mm wetsuit...

Do you get cold during an average dive ?
No, Never got Cold on either dives

Would you say that your exposure wear is tight?
Nup, The Drysuit has been my best friend for 2 years at that time, and was well Stretched in both neck and wrists, the wetsuit was nice an new, comfortable and yesh good!

My Diving Habbits... I am a photographer, videographer and a instructor, so all these things do not help... but I do NOT push limits, I dive to my tables or Computer, and compaired to some of the diving I have done the dives that I got the Hits from... were lets say MILD!

I have gotten just over 2k worth of dives, and 1000 of these were on the GBR in Australia chasing critters to 50-60m daily - 4-5 dives a day (not all that deep) and I have no issues, it just comes down to these easy ones that get me!

All this info has been great, please ask any questions as I am soaking all the information up!

Cameron.

Quote: (Originally Posted by shell-back)

when you say you are inherently prone to DCI, it sparks my interest in to your diving style and habits, you said both hits are in the arms "joint" elbow and muscle.

What was the temp of the water of said hits?
what type of exposure wear was used ?
Do you get cold during an average dive ?
would you say that your exposure wear is tight?

this is just speculation on my part but I,m interested in the questions posed and have a theory formulated in my own mind about capilary restriction due to temp and exposure of the joints.

As already stated the advantages of the higher po2 would be negated with longer exposures and I would be willing to bet the longer exposure would put you at higher risk for dcs if any correlation could be drawn of my opinion to the previous hits.

I'm not a doctor but I am married to one. It was the hardest degree I ever earned.Every once and a while I play one in the bedroom.

Def · 9th January 2006, 22:52

Hello Heather.

B1 was around dive 200ish, I was hydratred, rested, warm and comfortable, on a dive site I know way to well, diving with someone I knew very well... No grog for at least a week (hey it happens)

B2 was around dive 2000ish, again I was VERY hydrated (was packing down 6+ ltrs a day of water, plus any other drinks I had), no grog, lots of sleep and alot fitter than when B1 Happened (I was not UNFIT at b1, just fitter)..

I do dive 5-7 times a week, plus any courses I do, so Yes lets say I am in the water more in a month than most divers are in a year ... but .. why the ramdoms, why on easy dives.

These questions are the ones I am asking my self!

Thanks for the input !

Cameron.

Quote: (Originally Posted by hchoat)

While you give us some idea of your background, you don't provide us with information regarding profiles, gasses, etc. I would suggest to you that 2 minor "hits" in 500 plus dives for a very active diver is not unreasonable. Bear in mind that DCI is a sports injury. There are NO guarantees that you won't take a "hit" on any given dive for no perceptible reason. I would be far more concerned with your hydration level, fatigue level, etc. at this point than saying you are "prone" to DCI.

Heather

Def · 9th January 2006, 22:59

Gday Neil,

Yeap I got a referrel to a specialist who did a full echocardiogram and unfortonalty nothing was found except a beating heart (much to my GFs suprise) so now I am talking to Dr Ryan about other tests that will 100% rule that out.

Cameron.

Quote: (Originally Posted by Sutty)

I would expect RBs to be better in terms of DCI risk - but only if you use them to make it so. If you use them to do longer, deeper dives and rack up similar amounts deco as you used to on OC then perhaps not. If you dive to OC air profiles with one then yes.

You say you got the docs to check your heart and don't have a "hole". Was this a full checkout ie an echocardiogram looking specifically for a PFO, etc. Simple tests like listening with a stethoscope (and some more complex tests) may not show a PFO. I'd want some input from a cardiologist with an interest in diving medicine.

Neil

Def · 9th January 2006, 23:12

Rob,

This is what I am planning to use the Rebreather for, as I have not been able to find me a cute blond swedish female gas blender who is happy to mount my back for a hour while we get all wet together.....

It will be a safty device to give me the best % of O2 for that depth, my diving will not overly change in depths and time, but even if it does, I still have the advantage of having the best 02% for the dive.

Quote: (Originally Posted by ROB DAVIE)

Cameron,

Just so an eCCR will reduce your inert gas intake on any dive, again within its physical limits, of course, because it is akin to having a gas-mixing technician strapped to your back to provide the "best" possible gas fractions at any position in the water column.

Rob Davie
Rebreather World Admin

Sutty · 9th January 2006, 23:16

Quote: (Originally Posted by Def)

Gday Neil,

Yeap I got a referrel to a specialist who did a full echocardiogram and unfortonalty nothing was found except a beating heart (much to my GFs suprise) so now I am talking to Dr Ryan about other tests that will 100% rule that out.

Cameron.

I believe some of the more definitive tests involve injecting you with some bubbles (I think they use CO2), and seeing if they go from right heart to left heart with various manoevres. I forget the details though.

You mention that the hits were on "easy dives", is there a possibility that when you are on no-deco dives your ascents are a bit quick, whereas having to do stops obviously slows you, and you are getting bent on the no-stop ones?

shell-back · 9th January 2006, 23:26

HMMMMMMM ?
Looks as though you have that concept covered.
there goes that theory. If you are logging some serious repetative dives as I see from your reply. I think the rebreather is more suitable for you in terms of your "inert Load". Now you will have to keep a keen eye on the 02 clock and should with out a doubt have a Theoretical Physiological who-ha advantage.

you should play the lotto.

Quote:

Bear in mind that DCI is a sports injury.

Heather , I think that is a great analogy. It rates up there with the "death by misadventure".

Mike · 9th January 2006, 23:40

Quote: (Originally Posted by Def)

In 2001, I had a minor Joint 'unexplained' bend in my right arm, that was looked at and treated in POW Sydney, I was upto about dive 500 at the time.

Now in 2005 I had a second 'unexplained' bend in my left arm, this time it was not a joint but a muscel pain,

This may be a stupid question, but are you completely sure that you were actually bent on both occasions?

My understanding is that Drs will generally throw you in the chamber just to be sure, and there is really no way to definatively prove whether muscle pain was a bend, or a strain. If the pain immediately disappeared on pressurisation, I'd take that as a pretty strong indication however.
I know I've come home from diving with some pretty sore muscles/joints, sometimes I remember picking a twinset up in one hand at full stretch, sometimes I can't remember anything and I'm left rubbing a shoulder. It would have to be pretty bad pain for me to assume that, absent of any other factors, I had a localised unexplained hit.

As far as whether diving a rebreather will put you at less risk of DCS, I'd actually say no. Most likely you will find that you end up doing more deeper diving, and diving with people who are running minimum deco profiles for the dives. This will theoreticually increase your risk of getting DCS to twice bugger all...

If you dive the same profiles as you were doing on OC (does anyone do this?), then yes, your risk may decrease to half bugger all.

Mike

Def · 10th January 2006, 00:39

Mike,

I am pretty sure I was bent

B1 Symptoms - Inital - Pain in the wrist, Post - Pain Continued in Wrist, moved to elbo, then sholder, then lost of strengh in whole arm (was unable to turn the key in my car..., then the lost of appitite, then the whole I NEED to sleep...

B2 Symptoms - Inital - Apon Surfacing, Throwing up, getting on boat, 2minutes in Arm throbs like it was hit with a sledge - Post - Pain increased, head ache, O2 gave an near instant releif.

This dive was done on a single Steel 100 ....

If you can think of anything else that causes this, I am more than happy to listen.... I am not a pot screaming sissy

I only see a doc, or even make an issue when I am really in pain, or really sick....

This dive was done on twin 88's with 2 stages, but all carried to the boat by staff, and gear put on in water...

Regarding deeper / longer dives, I am happy to dive 60-70m on OC every day... there is not many wrecks or things I film for work past this depth, bottom times will increase maybe, but I think the joy of starting to off gassing as fast as possible using the best mix possible can only help.

I hope all this makes sense.

Cameron.

Quote: (Originally Posted by Mike)

This may be a stupid question, but are you completely sure that you were actually bent on both occasions?

My understanding is that Drs will generally throw you in the chamber just to be sure, and there is really no way to definatively prove whether muscle pain was a bend, or a strain. If the pain immediately disappeared on pressurisation, I'd take that as a pretty strong indication however.
I know I've come home from diving with some pretty sore muscles/joints, sometimes I remember picking a twinset up in one hand at full stretch, sometimes I can't remember anything and I'm left rubbing a shoulder. It would have to be pretty bad pain for me to assume that, absent of any other factors, I had a localised unexplained hit.

As far as whether diving a rebreather will put you at less risk of DCS, I'd actually say no. Most likely you will find that you end up doing more deeper diving, and diving with people who are running minimum deco profiles for the dives. This will theoreticually increase your risk of getting DCS to twice bugger all...

If you dive the same profiles as you were doing on OC (does anyone do this?), then yes, your risk may decrease to half bugger all.

Mike

9th January 2006, 20:56	#11 (permalink)
hchoat Resident Selkie Current Rebreather/s: Megalodon Other Rebreather/s: Join Date: Aug 2005 Location: Pensacola, FL- USA Posts: 227	Re: Are Rebreathers Safer for DCI prone divers than OC While you give us some idea of your background, you don't provide us with information regarding profiles, gasses, etc. I would suggest to you that 2 minor "hits" in 500 plus dives for a very active diver is not unreasonable. Bear in mind that DCI is a sports injury. There are NO guarantees that you won't take a "hit" on any given dive for no perceptible reason. I would be far more concerned with your hydration level, fatigue level, etc. at this point than saying you are "prone" to DCI. Heather __________________ Duct tape is like the force... it has a light side and dark side, and it holds the universe together.
(Online)

9th January 2006, 22:19	#12 (permalink)
wizbang WEB MERMEN Current Rebreather/s: Inspiration Classic Dolphin Home Build Other Rebreather/s: Not Bought Yet Inspiration Vision Evolution Prism Topaz Sport Kiss Classic Kiss Dolphin Home Build Join Date: Feb 2005 Location: Perth Australia Posts: 386	Re: Are Rebreathers Safer for DCI prone divers than OC Quote: (Originally Posted by hchoat) While you give us some idea of your background, you don't provide us with information regarding profiles, gasses, etc. I would suggest to you that 2 minor "hits" in 500 plus dives for a very active diver is not unreasonable. Bear in mind that DCI is a sports injury. Heather I have had no hits in 2200 odd dives (not an instructor). Certainly 2 in 500 would have made me think twice about my chosen sport. A sports injury? An injury aquired while playing sport. Sure A twisted/sprained ankle in Netball / football is my definition of sports injury. A broken neck from football also fits the definition but is certainly at the extreme end. Quote: There are NO guarantees that you won't take a "hit" on any given dive for no perceptible reason. I would be far more concerned with your hydration level, fatigue level, etc. at this point than saying you are "prone" to DCI. I agree. IMHO Deco Theory is pseudoscience. Best guess by some smart people is how I look at it. I do think some people are more "prone" than others. (ie std distribution curve) but the factors you mention can make it better or worse depending on how you look after yourself.
(Offline)

9th January 2006, 22:48	#13 (permalink)
Def New Member Current Rebreather/s: Inspiration Vision Other Rebreather/s: Join Date: Jan 2006 Location: Sydney Posts: 83	Re: Are Rebreathers Safer for DCI prone divers than OC Gday Shellback, To Answer your questions, I will quote them as B1 and B2 (bend 1 and Bend 2) >What was the temp of the water of said hits? B1 - 18-19d water temp, 23-24d Air Temp, Diving in a Dry Suit... B2 - 27-29d water temp, 29-34d Air Temp, in a 3mm wetsuit... Do you get cold during an average dive ? No, Never got Cold on either dives Would you say that your exposure wear is tight? Nup, The Drysuit has been my best friend for 2 years at that time, and was well Stretched in both neck and wrists, the wetsuit was nice an new, comfortable and yesh good! My Diving Habbits... I am a photographer, videographer and a instructor, so all these things do not help... but I do NOT push limits, I dive to my tables or Computer, and compaired to some of the diving I have done the dives that I got the Hits from... were lets say MILD! I have gotten just over 2k worth of dives, and 1000 of these were on the GBR in Australia chasing critters to 50-60m daily - 4-5 dives a day (not all that deep) and I have no issues, it just comes down to these easy ones that get me! All this info has been great, please ask any questions as I am soaking all the information up! Cameron. Quote: (Originally Posted by shell-back) when you say you are inherently prone to DCI, it sparks my interest in to your diving style and habits, you said both hits are in the arms "joint" elbow and muscle. What was the temp of the water of said hits? what type of exposure wear was used ? Do you get cold during an average dive ? would you say that your exposure wear is tight? this is just speculation on my part but I,m interested in the questions posed and have a theory formulated in my own mind about capilary restriction due to temp and exposure of the joints. As already stated the advantages of the higher po2 would be negated with longer exposures and I would be willing to bet the longer exposure would put you at higher risk for dcs if any correlation could be drawn of my opinion to the previous hits. I'm not a doctor but I am married to one. It was the hardest degree I ever earned.Every once and a while I play one in the bedroom.
(Offline)

9th January 2006, 22:52	#14 (permalink)
Def New Member Current Rebreather/s: Inspiration Vision Other Rebreather/s: Join Date: Jan 2006 Location: Sydney Posts: 83	Re: Are Rebreathers Safer for DCI prone divers than OC Hello Heather. B1 was around dive 200ish, I was hydratred, rested, warm and comfortable, on a dive site I know way to well, diving with someone I knew very well... No grog for at least a week (hey it happens) B2 was around dive 2000ish, again I was VERY hydrated (was packing down 6+ ltrs a day of water, plus any other drinks I had), no grog, lots of sleep and alot fitter than when B1 Happened (I was not UNFIT at b1, just fitter).. I do dive 5-7 times a week, plus any courses I do, so Yes lets say I am in the water more in a month than most divers are in a year ... but .. why the ramdoms, why on easy dives. These questions are the ones I am asking my self! Thanks for the input ! Cameron. Quote: (Originally Posted by hchoat) While you give us some idea of your background, you don't provide us with information regarding profiles, gasses, etc. I would suggest to you that 2 minor "hits" in 500 plus dives for a very active diver is not unreasonable. Bear in mind that DCI is a sports injury. There are NO guarantees that you won't take a "hit" on any given dive for no perceptible reason. I would be far more concerned with your hydration level, fatigue level, etc. at this point than saying you are "prone" to DCI. Heather
(Offline)

9th January 2006, 22:59	#15 (permalink)
Def New Member Current Rebreather/s: Inspiration Vision Other Rebreather/s: Join Date: Jan 2006 Location: Sydney Posts: 83	Re: Are Rebreathers Safer for DCI prone divers than OC Gday Neil, Yeap I got a referrel to a specialist who did a full echocardiogram and unfortonalty nothing was found except a beating heart (much to my GFs suprise) so now I am talking to Dr Ryan about other tests that will 100% rule that out. Cameron. Quote: (Originally Posted by Sutty) I would expect RBs to be better in terms of DCI risk - but only if you use them to make it so. If you use them to do longer, deeper dives and rack up similar amounts deco as you used to on OC then perhaps not. If you dive to OC air profiles with one then yes. You say you got the docs to check your heart and don't have a "hole". Was this a full checkout ie an echocardiogram looking specifically for a PFO, etc. Simple tests like listening with a stethoscope (and some more complex tests) may not show a PFO. I'd want some input from a cardiologist with an interest in diving medicine. Neil
(Offline)

9th January 2006, 23:12	#16 (permalink)
Def New Member Current Rebreather/s: Inspiration Vision Other Rebreather/s: Join Date: Jan 2006 Location: Sydney Posts: 83	Re: Are Rebreathers Safer for DCI prone divers than OC Rob, This is what I am planning to use the Rebreather for, as I have not been able to find me a cute blond swedish female gas blender who is happy to mount my back for a hour while we get all wet together..... It will be a safty device to give me the best % of O2 for that depth, my diving will not overly change in depths and time, but even if it does, I still have the advantage of having the best 02% for the dive. Quote: (Originally Posted by ROB DAVIE) Cameron, Just so an eCCR will reduce your inert gas intake on any dive, again within its physical limits, of course, because it is akin to having a gas-mixing technician strapped to your back to provide the "best" possible gas fractions at any position in the water column. Rob Davie Rebreather World Admin
(Offline)

9th January 2006, 23:16	#17 (permalink)
Sutty Classic Kiss diver Current Rebreather/s: Classic Kiss Other Rebreather/s: Join Date: Jun 2005 Location: Glossop, Derbyshire, UK Posts: 802	Re: Are Rebreathers Safer for DCI prone divers than OC Quote: (Originally Posted by Def) Gday Neil, Yeap I got a referrel to a specialist who did a full echocardiogram and unfortonalty nothing was found except a beating heart (much to my GFs suprise) so now I am talking to Dr Ryan about other tests that will 100% rule that out. Cameron. I believe some of the more definitive tests involve injecting you with some bubbles (I think they use CO2), and seeing if they go from right heart to left heart with various manoevres. I forget the details though. You mention that the hits were on "easy dives", is there a possibility that when you are on no-deco dives your ascents are a bit quick, whereas having to do stops obviously slows you, and you are getting bent on the no-stop ones?
(Online)

9th January 2006, 23:26	#18 (permalink)
shell-back I do all my own stunts Current Rebreather/s: Other CCR Dolphin Ray Azimuth Other SCR Home Build Other Rebreather/s: Other CCR Dolphin Ray Azimuth Other SCR Home Build Join Date: Jul 2005 Location: middle of US Posts: 481	Re: Are Rebreathers Safer for DCI prone divers than OC HMMMMMMM ? Looks as though you have that concept covered. there goes that theory. If you are logging some serious repetative dives as I see from your reply. I think the rebreather is more suitable for you in terms of your "inert Load". Now you will have to keep a keen eye on the 02 clock and should with out a doubt have a Theoretical Physiological who-ha advantage. you should play the lotto. Quote: Bear in mind that DCI is a sports injury. Heather , I think that is a great analogy. It rates up there with the "death by misadventure".
(Offline)

9th January 2006, 23:40	#19 (permalink)
Mike Prism 'prentice Current Rebreather/s: Prism Topaz Other Rebreather/s: Inspiration Classic Evolution Join Date: Feb 2005 Location: Melbourne Posts: 329	Re: Are Rebreathers Safer for DCI prone divers than OC Quote: (Originally Posted by Def) In 2001, I had a minor Joint 'unexplained' bend in my right arm, that was looked at and treated in POW Sydney, I was upto about dive 500 at the time. Now in 2005 I had a second 'unexplained' bend in my left arm, this time it was not a joint but a muscel pain, This may be a stupid question, but are you completely sure that you were actually bent on both occasions? My understanding is that Drs will generally throw you in the chamber just to be sure, and there is really no way to definatively prove whether muscle pain was a bend, or a strain. If the pain immediately disappeared on pressurisation, I'd take that as a pretty strong indication however. I know I've come home from diving with some pretty sore muscles/joints, sometimes I remember picking a twinset up in one hand at full stretch, sometimes I can't remember anything and I'm left rubbing a shoulder. It would have to be pretty bad pain for me to assume that, absent of any other factors, I had a localised unexplained hit. As far as whether diving a rebreather will put you at less risk of DCS, I'd actually say no. Most likely you will find that you end up doing more deeper diving, and diving with people who are running minimum deco profiles for the dives. This will theoreticually increase your risk of getting DCS to twice bugger all... If you dive the same profiles as you were doing on OC (does anyone do this?), then yes, your risk may decrease to half bugger all. Mike __________________ Open ....... Closed Mind ........ Loop
(Offline)

10th January 2006, 00:39	#20 (permalink)
Def New Member Current Rebreather/s: Inspiration Vision Other Rebreather/s: Join Date: Jan 2006 Location: Sydney Posts: 83	Re: Are Rebreathers Safer for DCI prone divers than OC Mike, I am pretty sure I was bent B1 Symptoms - Inital - Pain in the wrist, Post - Pain Continued in Wrist, moved to elbo, then sholder, then lost of strengh in whole arm (was unable to turn the key in my car..., then the lost of appitite, then the whole I NEED to sleep... B2 Symptoms - Inital - Apon Surfacing, Throwing up, getting on boat, 2minutes in Arm throbs like it was hit with a sledge - Post - Pain increased, head ache, O2 gave an near instant releif. This dive was done on a single Steel 100 .... If you can think of anything else that causes this, I am more than happy to listen.... I am not a pot screaming sissy I only see a doc, or even make an issue when I am really in pain, or really sick.... This dive was done on twin 88's with 2 stages, but all carried to the boat by staff, and gear put on in water... Regarding deeper / longer dives, I am happy to dive 60-70m on OC every day... there is not many wrecks or things I film for work past this depth, bottom times will increase maybe, but I think the joy of starting to off gassing as fast as possible using the best mix possible can only help. I hope all this makes sense. Cameron. Quote: (Originally Posted by Mike) This may be a stupid question, but are you completely sure that you were actually bent on both occasions? My understanding is that Drs will generally throw you in the chamber just to be sure, and there is really no way to definatively prove whether muscle pain was a bend, or a strain. If the pain immediately disappeared on pressurisation, I'd take that as a pretty strong indication however. I know I've come home from diving with some pretty sore muscles/joints, sometimes I remember picking a twinset up in one hand at full stretch, sometimes I can't remember anything and I'm left rubbing a shoulder. It would have to be pretty bad pain for me to assume that, absent of any other factors, I had a localised unexplained hit. As far as whether diving a rebreather will put you at less risk of DCS, I'd actually say no. Most likely you will find that you end up doing more deeper diving, and diving with people who are running minimum deco profiles for the dives. This will theoreticually increase your risk of getting DCS to twice bugger all... If you dive the same profiles as you were doing on OC (does anyone do this?), then yes, your risk may decrease to half bugger all. Mike
(Offline)

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode