Article: In-Water Recompression

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

Saying that in water recompression "never" is an option is like saying its never an option to chop your arm off to save your life..
Some measures may be risky, but risky beat being permanently disabled or dead any day in my book.
 
Another tank of air? Probably not. Breathing pure oxygen at 20', in a full face mask ideally with voice communications to the surface, monitored by a tender, adequate thermal protection, in protected waters, and everyone involved well trained to identify Oxygen toxicity symptoms? Probably yes if the symptoms aren’t too severe.

Keep in mind that a decompression treatment starts with a Table 5 at 60' on pure O2 in a chamber. The increased PPO2 and compression is pretty significant and adverse reactions are much more manageable. This may help explain some of it: http://www.scubaboard.com/forums/diving-medicine/440726-oxygen-toxicity-limits-symptoms.html

There is a risk-reward balance: http://www.scubaboard.com/forums/ad...thoughts-water-recompression.html#post5419046

I sure would prefer O2 at 60 feet in a chamber but saying that it can't be done on air is really saying that decompression diving doesn't work, that once you have the nitrogen in your body, going through a series of decompression stops on air just puts more nitrogen in your body and you are in more and more danger. I've seen a decompression chamber that I don't believe was ever used with anything but air. Was that just snake oil with no hope for the guy inside it?
 
I sure would prefer O2 at 60 feet in a chamber but saying that it can't be done on air is really saying that decompression diving doesn't work, that once you have the nitrogen in your body, going through a series of decompression stops on air just puts more nitrogen in your body and you are in more and more danger…

Sorry for the confusion. Nobody said it can’t be done. It is more a question of efficacy. Recompressing to 20-30' in the water on pure O2 is much more effective than doing all air treatment for which tables don’t exist. Much deeper in the water and the risk of Oxygen Toxicity starts to exceed the benefit.

In-water Recompression | Rubicon Foundation

It is an extremely complex calculation to determine what critical tissues are absorbing more Nitrogen/diluent gas instead of giving it off. No calculations are necessary breathing pure Oxygen. There isn’t any that can be absorbed. In addition, diluent gas will transfer across the alveoli at accelerated rates, even on deck.

Increasing the ambient pressure accelerates blood to lung transfer even more — in the water or in a chamber. It also compresses any gas bubbles that may be compromising blood flow or even physically damaging tissue. That part is pretty simple — until the diver convulses and/or has serious DCS-induced medical complications. That is the whole basis of the IWR debate and what makes it far less prudent without a lot of preparation and training.

…I've seen a decompression chamber that I don't believe was ever used with anything but air. Was that just snake oil with no hope for the guy inside it?

I have ever seen a treatment chamber without oxygen, even ones made in the 1920s. In fact, I don’t recall ever seeing a treatment table that didn’t use pure Oxygen shallower than 60'. There are a few chambers that have been converted for recreational diver training that are no longer set up for treatment, which may be what you saw.

A treatment chamber without pure O2 is non-operational. It is snake oil if some idiot says otherwise.
 
I have ever seen a treatment chamber without oxygen, even ones made in the 1920s. In fact, I don’t recall ever seeing a treatment table that didn’t use pure Oxygen shallower than 60'. There are a few chambers that have been converted for recreational diver training that are no longer set up for treatment, which may be what you saw.

A treatment chamber without pure O2 is non-operational. It is snake oil if some idiot says otherwise.

I'm not trying to be confrontational but to learn. Can you show me a reference to hyperbaric O2 treatment for DCI before the 30's?
 
… Can you show me a reference to hyperbaric O2 treatment for DCI before the 30's?

Pure O2 was introduced for DCS treatment in the late 1930s by the US Navy’s Dr. Albert Behnke. I wouldn’t be surprised if it took until the 1940s to make it into a Navy Manual. Robert H. Davis wrote about US and British Royal Experimental Diving Units (and the US’s predecessor at the Brooklyn Navy Yard) studying use of pure O2 to accelerate decompression during the 1920s in his book, Deep Diving and Submarine Operations. That work lead to some of the Helium-Oxygen decompression tables and Surface Decompression Using Oxygen tables that also came in the 1930s and 40s.

I never meant to imply that chambers built in the 1920s were fitting with Oxygen BIBS masks... I wouldn't know. I only wrote that the chambers I have seen that were built as early as the 1920s were fitted, probably retro-fitted, with oxygen by the time I saw my first chamber in the mid-1960s. I don’t have any US or Royal Navy manuals older then the 1950s where there may have been some air DCS treatment tables. Wish I did. I do have a re-print of the USN 1916 Diving Manual, but there are only two pages of decompression tables.

http://www.hogrefe.com/program/media/catalog/Book/978-0-88937-361-7_Chapter1.pdf See page 6:

The potential benefits of using oxygen under pressure for the treatment of decompression sickness were first realized by Dräger, who in 1917 devised a system for treating diving accidents (Figure 1.6). For some unknown reason, however, Dräger’s system never went into production. It was not until 1937 - the very year that Cunning-ham's "air chamber" hotel was demolished - that Behnke and Shaw actually used hyperbaric oxygen for the treatment of decompression sickness. The age of Hyperbaric Oxygen (HBO) therapy had finally arrived.
 
Last edited:
That's what I found too. There are references to recompression chambers earlier but it doesn't really say how they did it, if they did some sort of a schedule on air or not. Of course for history like that a library may be better than the internet.
 
Is the author accurate in representing IWR as non-medical? What concerns me is the author's definitive "best method" without apparent caveat as a conclusion, yet the story was filled with opportunity for disaster.
 
… There are references to recompression chambers earlier but it doesn't really say how they did it, if they did some sort of a schedule on air or not. Of course for history like that a library may be better than the internet.

There isn’t much in books either. Diving before the 1950s was virtually all using deep sea gear. There were a few sponge divers going deep and the very rare submarine rescue, but for the most part the work was less than 40'. The first decompression tables were developed more for caisson workers building bridges than divers.

The world’s navies paid for virtually all hyperbaric research but budgets were tiny because all their work was in harbors. Submarine disasters loosened up what little money was spent, and even then it was a low military priority. If it weren’t for a few powerful personalities willing to put their careers at risk it wouldn’t have been funded until decades later.

From what I could gather from divers ready to retire when I was in the Navy, early chambers were justified to treat omitted decompression more than what we would consider a treatment. Even then, the decompression probably resulted from entrapment than planned. Most were single lock chambers, and all were riveted. I understood that the “treatment” for DCS at the Experimental Diving Unit while they were developing/improving decompression tables mostly consisted of running them back down to their deepest stop and repeating or adding some time. You also have to remember that slide-rules were all they had to aid in the calculations.

As a result, there wasn’t much motivation to develop proper treatment tables until about the time that Oxygen was finally accepted in the late 1930s. Dräger’s system in 1917 never went anywhere because the war was nearing the end and money was needed to fight.

That is the same Dräger that we know today. I did some work with Dräger outside of Lübeck in the 1970s. There were photos of some of their early chambers on the wall but I couldn’t read any of the captions. If you are really interested you might get some insight from Gerhard Haux’s book Tauchtechnik Volume 1 & 2, Springer Verlag 1969. It deals mostly current Dräger products of the day but there might be some history buried in the text. Unfortunately, I don’t read German. Tons of photos and illustrations though.

You might be able to dig out some clues from Robert Davis’ book mentioned above. It is probably the best history of diving in that era available. You might be able to find a US Navy diving manual from 1924, 43, and 52 that might give you more insight as well. Of course the best library is at EDU in Panama City Florida. Please let us know what you learn.
 
Last edited:
This diver Joe, is a total idiot.
 

Back
Top Bottom