Creatine & DCS Prevention?

[Web Monkey]

Being tired may be a sub-clinical indication of a bubble load, but still be far away from causing any lasting harm. Of course there could be any number of other things that cause fatigue. So saying fatigue is due to DCS is conjecture. I’d just ask if there is anything other than folklore that relates hydration to DCS. I suspect no one will be able to point to a study that shows a correlation. Which does not mean it does not exist. But the foundations may be far less firm than you imagine.

Reasonable amounts of water are safe? Reasonable amounts of many things are safe but not generally claimed to be preventive.

Whether or not water prevents DCS is irrelevant. The point is that it does no harm.

Creatine has a number of known effects and side effects and no clear indication that it's safe for diving.

Terry

 

[Mr Carcharodon]

Whether or not water prevents DCS is irrelevant. The point is that it does no harm.

Creatine has a number of known effects and side effects and no clear indication that it's safe for diving.

Terry

The claim was relevant to this discussion. Specifically the claim was creatine equals increased hydration and that leads to decreased DCS risk. I was pointing out there is no verifiable indication that hydration decreases risk of DCS. Water may be safe, but many safe things do nothing to decrease the risk of DCS. Performing a harmless activity like drinking water and decreasing your DCS risk are not the same.

I am poking at what I believe to be unverified conventional wisdom. I'd be happy to be shown wrong. But the premise of the original post may have no foundation.

 

[Bubbletrubble]

I was pointing out there is no verifiable indication that hydration decreases risk of DCS.

I am poking at what I believe to be unverified conventional wisdom. I'd be happy to be shown wrong. But the premise of the original post may have no foundation.

@Mr Carcharodon: You could make a far more compelling argument if you cited some peer-reviewed papers which suggest that dehydration does not increase the incidence of DCS. Here's one:

• Skogland S, Stuhr LB, Sundland H, Olsen RE, Hope A. Venous gas emboli in normal and dehydrated rats following decompression from a saturation dive. Aviat Space Environ Med. 2008 Jun;79(6):565-9.
  The methodology for this study consisted of dehydrating rats by withholding water for 2 days prior to trials. Control rats were given access to water ad libitum. The rats were subjected to a saturation dive to 5 ata and allowed to breathe heliox for 16 hrs. At the end of the dive, they ascended at a rate of 0.3 MPa/min. Bubble grade scores were actually lower in the dehydrated rats.

 

[Bubbletrubble]

I suspect no one will be able to point to a study that shows a correlation.

@Mr Carcharodon:

• Gempp E, Blatteau JE, Pontier JM, Balestra C, Louge P. Preventive effect of pre-dive hydration on bubble formation in divers. Br J Sports Med. 2009 Mar;43(3):224-8. Epub 2008 Feb 28.

Here's a direct link to the article on the British Journal of Sports Medicine website.

The methodology used in this study consisted of divers who, in one trial, drank a saline-glucose beverage pre-dive and, in another trial, did not engage in any pre-dive hydration. The saline-glucose beverage had a volume of 1300 mL (324 mOsm/L), and subjects drank this beverage over a time frame of 50 and 60 min. The dive profile was 30 msw for 30 min followed by a safety stop at 3 msw for 9 min.
Precordial pulsed Doppler was used to determine bubble scores (Spencer scale then converted to KISS). Divers during the pre-dive hydration trial had significantly lower bubble scores than during the trial lacking prehydration. Plasma volume was shown to be significantly higher in the prehydration trial. There was no difference in plasma surface tension between the two trials.

 

[Bubbletrubble]

Mr Carcharodon makes a good point, though. A look at the literature will show that there is a fair amount of disagreement as to whether adequate hydration decreases the incidence of DCI.

Perhaps instead of flooding ourselves with fluids before a dive, we should be doing a little exercise:

• Claybaugh JR, Lin YC. Exercise and decompression sickness: a matter of intensity and timing. J Physiol. 2004 Mar 16;555(Pt 3):588. Epub 2004 Feb 6.

Here's a direct link to the editorial commentary on PubMed Central.

Here's a PubMed citation link to the primary research article discussed in the editorial.
Here's a direct link to that primary research article by Dujic et al.

 

[Web Monkey]

Mr Carcharodon makes a good point, though. A look at the literature will show that there is a fair amount of disagreement as to whether adequate hydration decreases the incidence of DCI.

Perhaps instead of flooding ourselves with fluids before a dive, we should be doing a little exercise:

Or just staying away from the NDL.

Terry

 

[Mr Carcharodon]

Thanks for the links. I have only read the first one so far. The last sentence in the abstract was: "This difference was not significant". Which is to say there was no significant difference in bubble load with hydration levels.

Also bubble load does not equal DCS at least below a threshold. So about the best you can argue is that hydration might decrease bubble loads which might in turn put you over a DCS threshold in certain circumstances. I'll look forward to reading the other two. Thanks again for the links.

I’d recommend longer stops since those clearly work.

 

[Bubbletrubble]

Also bubble load does not equal DCS at least below a threshold.

I agree. This is something that many divers don't realize. Doppler measurement of venous gas emboli is straightforward to do...but what is the true relevance of those readings to DCS? As you point out, bubbles can be present with no overt clinical symptoms. Still, the occurrence of lots of bubbles is clearly linked to a high risk of DCS. We don't really now how to interpret this. More research needs to be done.

So about the best you can argue is that hydration might decrease bubble loads which might in turn put you over a DCS threshold in certain circumstances.

Yup. (The key word is "might"...and you used it twice!) I included links to those two citations because the detection methodologies were similar -- bubble scores generated by precordial Doppler. This highlights the discrepancy in the results/conclusions. Something that I wonder about is how reproducible Doppler measurements are in the rat model -- smaller anatomy could make consistency problematic.

In all of the papers I've read on the subject, the authors have been very responsible in discussing the limitations of correlating bubble load with DCS. We should be just as careful.

Thanks for bringing up some very good points in this thread. Hopefully others have found the info thought-provoking.

 

[scubadobadoo]

The claim was relevant to this discussion. Specifically the claim was creatine equals increased hydration and that leads to decreased DCS risk. I was pointing out there is no verifiable indication that hydration decreases risk of DCS. Water may be safe, but many safe things do nothing to decrease the risk of DCS. Performing a harmless activity like drinking water and decreasing your DCS risk are not the same.

I am poking at what I believe to be unverified conventional wisdom. I'd be happy to be shown wrong. But the premise of the original post may have no foundation.

I look to a whole list of things to decrease my DCS risk and those include being hydrated (because being dehydrated IS a concern and does lead to problems even if increased hydration alone can't be proven to reduce your risk of DSC) , well rested, diving within my limits, staying warm, going to the gym and being reasonably fit, slowing my ascents etc.........

Simply pick up a cup and drink baby. In the end, I think DEHYDRATION is the concern. I don't think it can be proven that being well hydrated or more hydrated reduces your risk of DCS but anyone can clearly see that being dehydrated could lead to all kinds of problems on a dive. Therefore, drinking that water may in fact reduce your risk of a diving accident if it helps to keep you from becoming DEHYDRATED as we know it can.

 

[Mr Carcharodon]

I look to a whole list of things to decrease my DCS risk and those include being hydrated (because being dehydrated IS a concern and does lead to problems even if increased hydration alone can't be proven to reduce your risk of DSC) , well rested, diving within my limits, staying warm, going to the gym and being reasonably fit, slowing my ascents etc.........

Simply pick up a cup and drink baby. In the end, I think DEHYDRATION is the concern. I don't think it can be proven that being well hydrated or more hydrated reduces your risk of DCS but anyone can clearly see that being dehydrated could lead to all kinds of problems on a dive. Therefore, drinking that water may in fact reduce your risk of a diving accident if it helps to keep you from becoming DEHYDRATED as we know it can.

By all means go ahead and drink water if you want to it will do no harm and it may help a bit (apart from the potential for a smelly wetsuit). I am just suggesting that the things we know with confidence reduce DCS risk are staying away from no decompression limits or doing conservative stops to decompress on the way back up. Dehydration may be a factor but it is a weak one at least within extremes. Three to five minutes between twenty and ten feet will do more to prevent DCS than drinking a liter of water. Please focus in the right place.

I did troll around a bit tonight in the literature and did not find a smoking gun that relates dehydration to DCS. Although I do not have subscriptions to all the relevant journals. Rubicon does have a number of citations but few things checked in. If I am am headed down a wrong path please do let me, and everyone else, know.