Alternative to Chamber?

[graywhale]

DCBC,

I'm sure you are much more experienced on these technical issues and experience. So the reports and stories I am retelling can have counterweights and stories from people like your that caution differently. We need all aspects of this, though the reports I am reading from MDs and cases is compelling that IWR is effective. But maybe I'm missing something, that's why discussions are healthy and provoke the exchange of information.

So let's take your personal experience: Let's pretend that you believed IWR was effective in your experience. What condition or symptom of your buddy would have prevented you from reintroducing him back into the water? Does a face mask not work as the MD says it should, or was the medical condition such that it would have been impossible? IF so, could you give some more details?....I'm not being nosy or judgmental, just trying to see if there are details the other reports are missing.

 

[Mr Carcharodon]

If you go much deeper than 30 fsw on air you will be on gassing rather than offgassing unless you were near saturation for a greater depth to begin with.

 

[DandyDon]

I think our new member GW makes a lot from anecdotal information of questionable accuracy. As far as the two divers story, we do not know details on how badly each was hit or other factors in play. Interesting story of little real value.

 

[DCBC]

graywhale: To take my team member as an example, his Type II DCS symptoms included:
1. Dyspnea to the point that breathing was unsteady. He latter told me he felt suffocated which was complicated by a burning chest pain, this resulted in bouts of panic.
2. Vomitting (FFM or not, this is a problem).
3. General seizure followed by a brief loss of consciousness
4. Dehydration most likely complicated by the use of the Hot Water Dry Suit
5. This DCS was severe in that it had neurological symptoms

Another point is that AGE may accompany DCS. This was not the case in my example, but they often accompany each other. Things can get complicated really fast and there you are still in the water. I can't stress the problems and complications of prolonged cold water immersion strongly enough.

This case turnedout positively due to an on-site chanber and qualified medical help available. It did however scare the hell out of me...

 

[graywhale]

Dandydon,
well I have no direct experience, so I have to read up on it as it was a question I was wondering about and lo and behold, there actually is a ton of empirical information and studies done on dods and hogs regarding IWR.

In all fairness, if you or anyone is against IWR, please state the exact reason, so we may all learn. Otherwise the post is useless. Why for instance, would you say that the information I have quoted is anecdotal information of questionable accuracy?? That's a very strong statement that I think you should clarify in detail. If what you are saying is true, that would shed a very bad light on the many studies and MDs I have quoted and should become known.

Ignorance is the evil here. Just saying don't do it, it doesn't work, it's dangerous, etc...without anything to back it up, is really not helpful in finding the optimal course of action in my hypothetical situation were you are bent and far from a chamber. What to do in that situation?

The current DAN recommendation is breath 100% oxygen topside and transport to a chamber, no matter how far it is, how severe the DCS symptoms are or how quickly they are developing. After doing all the reading today, I am convinced that in severe cases IWR is the best unless a chamber is available within 10 minutes.

In mild cases IWR is best if a chamber is not available within 3 hours tops. The reason is because DCS gets worse over time and bubbles grow and accumulate over time. At 100 FSW it takes all of 3 minutes for the bubbles to go away. That's why people see almost instant relief by going down again. It then becomes a question to have a planned procedure of how deep for how long breathing what gas mix, ascending at what rate and the post surface treatment.

In panel discussions, it's also been speculated that if 100% Oxygen is not available, that breathing NITROX during the IWR with as high an Oxygen content as possible would also do better than pure air.

The Hawaii method is to dive back to at least 100 feet on air and then once back up to 30 feet, switch to 100% oxygen and the continue on 100% oxygen once back on the surface for a few hours. They're convinced it works and the professional divers of Hawaii use this. That's all I can say.........

 

[graywhale]

DCBC,
Thanks for sharing. You did have the chamber. What would you have done if it was not available? In a severe situation like yours, it's a question of life and death for sure. Do you think your buddy would have survived without the quick chamber access? How long did ti take for unconsciousness to set in? In the studies I've read, the researchers indicate that at 100 feet it takes no more than 3 minutes for bubbles to be completely undetectable via doppler. So if unconsciousness and other major symptoms set in after say 20 minutes after surfacing, then immediate IWR would have avoided a lot of those symptoms to begin with.

I understand the issue about cold water, but your buddy was already equipped for cold water as you stated anyway, no? In any case, this is a severe stress test situation where the choices can only be amongst the least worst, if all the choices are not desirable.

Thank God you had an on site chamber and your buddy turned out OK. But my question is what to do precisely when there isn't a chamber available well past 3 hours?

 

[Gene_Hobbs]

Seeing the direction of this tread makes me think it is worth defining DCS and what might be in need of attention or not. This might be of interest to a few of you.

Mitchell SJ, Doolette DJ, Wachholz CJ, Vann RD (eds.). 2005. Management of Mild or Marginal Decompression Illness in Remote Locations Workshop Proceedings. Durham NC: Divers Alert Network. 240 pages. RRR ID: 5523

 

[graywhale]

"it is worth defining DCS and what might be in need of attention or not."

That is an excellent starting point. This should be taught in the OW courses right off the bat. And even teach that divers will get bent for sure if an uncontrolled rapid ascent or emergency rapid ascent happens for any number of reasons. If this happens, there is no need to wait for the onset of symptoms to kick the emergency plan into gear, either going to chamber or IWR or both.

The frustrating thing for me is that what we are discussing here in this thread is not taught in OW courses. It is not discussed what DCS really is nor what to do about it except for seeking immediate medical help if certain common symptoms crop up.

The topic of IWR has already been well thought out by the different diving communities, but it needs to be taught as a first aid procedure to at least the DMs and above to be applied - when other help is too far away or when it would clearly be beneficial.

Otherwise, what was said by another poster will remain true, namely that it will seem too complicated, vague and unknown - because nobody teaches it formally and no authoritative body endorses it - and so it will always be completely avoided.

That's my take and many thank to Rubicon for storing the documents I downloaded on this subject. It's invaluable to read the information directly from the horses mouth.

Thanks again all. I've learned a lot today and played out in my mind what I would do and I'm sure I'll continue to learn..........

 

[bamamedic]

In water recompression is an option, but for the vast majority of DCS cases, it's a bad option.

For one thing, you've got to consider the mental state of the patient/diver. He or she is feeling horrible, is in pain, and may very not be mentally up to a dive that could last hours. There's no point in putting a bent diver back in the water, if he or she is just going to bolt for the surface after a few minutes.

Then, there's the whole thing about O2 toxicity. Sur,e, the answer seems simple...slap a FFM on the bent diver and send him back down. However, (and I don't know about you), but I don't dive with a FFM, and I don't know any divers (other than public safety divers while working) who do. Furthermore, those things are expensive, and I doubt many recreational divers will be adopting them. Plus, a diver who has experienced a seizure will go thorugh a postictal phase, where he or she may be lethargic, confused, and even combative. Truthfully, the thought of having a postictal diver underwater (and not in an air-filled habitat) kind of scares me. The last thing the bent diver needs to do is become confused, pull off his or her FFM or bolt for the surface.

Plus, recompression therapy isn't as simple as sending the diver for a chamber ride and he's all better. Many divers suffering from DCS require multiple treatments for symptom resolution...that's not really practical with IWR. The DCS symptoms alone might rule out IWR...you don't want to send a diver back down who's experiencing pulmonary or neurological issues...and neurological symptoms can be very subtle at first.

You've also got to consider the environment you're diving in. Long exposures in cold water are not a good thing for offgassing. If the offgassing isn't going to be effective, there's little point in sending the diver back underwater.

There's the training and personnel issue. Is the bent diver capable of holding a 20 foot or 30 foot stop, even while feeling horrible? Are there medical personnel aboard the boat or readily available on shore in order to diagnose the diver with DCS and prescribe IWR? (not all illnesses are what they first seem).

Of course, you've got to think about supplies. There is absolutely no point (and you may very well do more harm than good), to sending a diver back down and then realizing that you do not have enough gas for them to complete IWR. Plus, you've got to account for the potentially increased SAC rate of a stressed diver.

Generally, (even when help/a chamber is a long ways away), DCS symptoms are better treated with 100% O2 on the surface, and transport to a medical facility, than with IWR. If the symptoms involve joint pain only, then the O2 should help quite a bit...and if the symptoms are neurological or pulmonary in nature, than IWR seems to be a really bad idea.

Well, that's my two cents....it's worth what you paid for it

 

[graywhale]

Thanks Bamamedic,
Good points. I was just reading "Management of Mild or Marginal Decompression Illness in Remote Locations Workshop Proceedings" from May 24-25, 2004.

There, many of your points are also discussed by various physicians. I for one think that the reason IWR is such a good solution if done with proper topside support and previously planned as a contingency, is that it is done very quickly, before the onset of very serious symptoms. From what I have been reading and my logic concurs is that waiting hours to treat a patient after an incident is exactly what causes severe symptoms and real damage and complications, which then need many treatments to overcome. Immediate recompression as only IWR can accomplish, is what saves the day. The harm and symptoms never even appear as in those that are out for hours before recompression. Speed is the factor.

Perhaps I should then clarify that IWR should be a pre-planned contingency option in case recompression is needed, and that it be done immediately or with minimal delay. The other thing is that the divers are educated in IWR and plan it as a contingency. Ad hoc would be crazy, I agree. It is precisely because divers have no plan execpt to call DAN, that the harm is exasperated.

Apparently technical divers do IWR all the time. This is from comments from that workshop. They don't even hesitate according to their statements, and the events are never reported nor are medics called. So this is not widely known nor are there reliable statistics gathered, like for military or recreational diver incidents. But the Tech divers are convinced and do IWR all the time when DCS is suspected. I'd assume they would not be enthusiastic if it didn't work for them.

Of course the know what they are doing, are prepared and do not hesitate and waste time at the surface. That's also key to their success. So I say, let's emulate success, get educated and prepared. That way a DM could call DAN and if the Physician determines that the DM is educated and prepared to do IWR to advise him to do it asap. Otherwise no.