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Skin bends...

Discussion in 'Ask Dr. Decompression' started by Pebbles Photo, May 13, 2019.

  1. Storker

    Storker Divemaster

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    Hugon et al., Diving and Hyperbaric Medicine 48(3) (2018), 132-140, doi: 10.28920/dhm48.3.132-140
     
    Duke Dive Medicine likes this.
  2. Duke Dive Medicine

    Duke Dive Medicine Medical Moderator Staff Member

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    Subclavian vein has been used as well; you get a picture of the upper extremities with that.
     
  3. Storker

    Storker Divemaster

    # of Dives: 100 - 199
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    Yep. My point exactly. And apparently some researchers think that it might give at least as reliable results as measuring the heart or the pulmonary.

    Me, I haven't a clue. Hyperbaric medicine isn't my specialty, so I lean heavily on the appeal to authority fallacy.
     
  4. michael-fisch

    michael-fisch Manta Ray

    # of Dives: 2,500 - 4,999
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    Sorry guys, when I stated limiting tissue I meant tissues that were limited by their gas supersaturation caused either by the helium in trimix or the nitrogen in slower gasses.
    Usually in a trimix non saturation deco dive the helium supersaturation in the tissues is higher than that caused by nitrogen, making helium the gas that limits the tissue and defines the necessary decompression. On longer trimix dives, the sum accumulation of nitrogen can also cause an undesireable supersaturation that has to be taken care of with your deco, unusual on the shorter decompression spike dives that most of us do, but with bottom time approaching 90 minutes (cave!) not uncommon. Thats one of the reasons why there are so many different decompression models, none of them right under all circumstances, but most of them work well, most of the time.

    Michael
     
  5. michael-fisch

    michael-fisch Manta Ray

    # of Dives: 2,500 - 4,999
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    It works best when done by people who know what they are doing, compared to it the carotid is easy enough to find with an 8mhz probe that any person can find it, hear it and understand what they are hearing with less than 60 seconds of instruction, the second time they can do it without instruction.

    Michael
     
  6. Storker

    Storker Divemaster

    # of Dives: 100 - 199
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    I have some issues squaring this with what Møllerløkken et al. are saying in Diving Hyperbaric Medicine 46(1), 26-32. Care to enlighten me?
     
  7. michael-fisch

    michael-fisch Manta Ray

    # of Dives: 2,500 - 4,999
    Location: Germany
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    Ok, I'm not sure that every politician can learn how in 60 seconds, but I was taught by Michael Waldbrenner about 20 years ago in less than 60 seconds, and have over the years taught 25+ Tekkies and Dive Instructors how to do it including finding the vein, and holding on it while listening to the blood flow and the bubbles swish past with around 60 seconds of instruction. Then testing that they can still do it 30 minutes later.
    Admittedly hearing the exact Spencer grade cannot be easily learned, but what counts is really differentiating between :
    Occasional bubble
    Bubbles
    Still countable bubbles
    and Too many bubbles to count

    Instead of riding your high horse, why don't you buy a cheap 8mhz doppler, and try it on yourself, your wife, and your son?
    Now you will understand what you are hearing, how to find it and what it sounds like. When you finally hear bubbles after the day's diving on a dive boat, you will know what you are hearing, and then you'll have to differentiate betweel occasional, steady but countable and too fast to count.

    Michael
     
  8. Storker

    Storker Divemaster

    # of Dives: 100 - 199
    Location: close to a Hell which occasionally freezes over
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    Which politician are you talking about? Honest question.

    I'm not riding any horse at all. I'm just a diver with a background in another science trying to understand hyperbaric medicine to the best of my abilities and what people without demonstrable scientific credentials are saying.

    And my apologies, but for some reason I'd rather trust credentialed scientists like Møllerløkken, Doolette and Pollock than some unidentified, uncredentialed bloke on an Internet forum.
     
  9. michael-fisch

    michael-fisch Manta Ray

    # of Dives: 2,500 - 4,999
    Location: Germany
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    If you can't get repeatable results, you will be the 1st person who can't.
    An expensive huntleigh 8mhz doppler is overkill, the cheap korean 8mhz dopplers for $120 work just as well for this purpose.

    Michael
     
  10. michael-fisch

    michael-fisch Manta Ray

    # of Dives: 2,500 - 4,999
    Location: Germany
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    Lets not get started with whoever's next term will hopefully be for life in Dannemora, NY

    This is about DCS and using a doppler as a diagnostic aid, lets try and keep politics out of it.

    Michael
     
    Schwob likes this.

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