+ Reply to Thread
Page 3 of 3 FirstFirst 1 2 3
Results 21 to 24 of 24

Thread: Missed the talk on deep CCR at Eurotek =(

  1. #21
    New Member Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell's Avatar
    Join Date
    May 2005
    Location
    New Zealand
    Posts
    683

    Re: Missed the talk on deep CCR at Eurotek =(

    Quote Originally Posted by jneves  View Original Post
    I obviously don’t know the testing and the results you mention but I would like the consult them… Would you be as kind as telling me where I could get those? Thanks.
    Hello again,

    You could try:

    Thalmann ED et al. Effects of immersion and static lung loading on submerged exercise at depth. Undersea Biomed Res 1979;6(3):259-90

    Hickey DD et al. Respiratory function in the upright working diver at 6.8ATA (190fsw). Undersea Biomed Res 1987;14(3):241-62

    Derion T et al. Static lung load and posture effects on pulmonary mechanics and comfort in underwater exercise. Undersea Biomed Res 1992;19(2):85-96

    We should not become too "bogged down" in debate about static lung loads, lest it be interpreted that this is the most important aspect of the problem. As I have alluded to earlier it is just one link in a multifactorial chain of events that can lead to hypercapnia and possibly respiratory failure underwater.

    Also, on reading your initial post again more carefully, it seems to me that what you are describing is an increase in dead space by distension of the conducting airways when there is a positive static lung load. If that were to happen, and it were associated with an increase in the dead space : tidal volume ratio (VD/VT) then it could contribute to hypoventilation, and as I have said, alveolar ventilation is the crucial issue in elimination of CO2. However, I am unaware of any evidence that this actually happens.

    Warm regards,

    Simon M

  2. #22
    RBW Member jneves is on a distinguished road jneves is on a distinguished road jneves's Avatar
    Join Date
    Apr 2007
    Location
    Lisbon
    Posts
    335
    Se7en/Mk6 Discovery/O2ptima

    DIY/Dolphin/Ray

    Re: Missed the talk on deep CCR at Eurotek =(

    Quote Originally Posted by Simon Mitchell  View Original Post
    Hello again,

    You could try:

    Thalmann ED et al. Effects of immersion and static lung loading on submerged exercise at depth. Undersea Biomed Res 1979;6(3):259-90

    Hickey DD et al. Respiratory function in the upright working diver at 6.8ATA (190fsw). Undersea Biomed Res 1987;14(3):241-62

    Derion T et al. Static lung load and posture effects on pulmonary mechanics and comfort in underwater exercise. Undersea Biomed Res 1992;19(2):85-96

    We should not become too "bogged down" in debate about static lung loads, lest it be interpreted that this is the most important aspect of the problem. As I have alluded to earlier it is just one link in a multifactorial chain of events that can lead to hypercapnia and possibly respiratory failure underwater.

    Also, on reading your initial post again more carefully, it seems to me that what you are describing is an increase in dead space by distension of the conducting airways when there is a positive static lung load. If that were to happen, and it were associated with an increase in the dead space : tidal volume ratio (VD/VT) then it could contribute to hypoventilation, and as I have said, alveolar ventilation is the crucial issue in elimination of CO2. However, I am unaware of any evidence that this actually happens.

    Warm regards,

    Simon M
    Hi again Simon,

    Sorry for taking your time and I do appreciate your help you are providing here. The reason for me to try to get as much information and different opinions as possible it the fact that I recently personally experienced moderately deep (85 m) in a cave the “down spiral” of Hypercapnia respiratory distress. I was lucky I got out alive. The drag is that I have been at those depths before, and at least with the same workload, and it never got so ugly… until that day. So I am very curious on what may have gone wrong.
    It is very important to get some insight as to the mechanics of the issue because some factors involved may only need a slight change to become the main trigger the CO2 off gassing unbalance. Let me know if I may PM you if you are willing to discuss this further.

    J Neves

  3. #23
    New Member Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell has a reputation beyond repute Simon Mitchell's Avatar
    Join Date
    May 2005
    Location
    New Zealand
    Posts
    683

    Re: Missed the talk on deep CCR at Eurotek =(

    Quote Originally Posted by jneves  View Original Post
    Hi again Simon,

    It is very important to get some insight as to the mechanics of the issue because some factors involved may only need a slight change to become the main trigger the CO2 off gassing unbalance.


    Totally agree.

    Quote Originally Posted by jneves  View Original Post
    Let me know if I may PM you if you are willing to discuss this further.

    J Neves
    No problem. There is quite a lot of material I can send you. If you pm me your email address I will respond with mine.

    Simon M

  4. #24
    Resident bibliophile Gene_Hobbs is a name known to all Gene_Hobbs is a name known to all Gene_Hobbs is a name known to all Gene_Hobbs is a name known to all Gene_Hobbs is a name known to all Gene_Hobbs is a name known to all Gene_Hobbs is a name known to all Gene_Hobbs is a name known to all Gene_Hobbs is a name known to all Gene_Hobbs is a name known to all Gene_Hobbs is a name known to all Gene_Hobbs's Avatar
    Join Date
    Sep 2006
    Location
    Durham, NC, USA
    Posts
    179
    Megalodon

    and links to the papers...

    Quote Originally Posted by Simon Mitchell  View Original Post
    Thalmann ED et al. Effects of immersion and static lung loading on submerged exercise at depth. Undersea Biomed Res 1979;6(3):259-90
    RRR ID: 2862

    Quote Originally Posted by Simon Mitchell  View Original Post
    Hickey DD et al. Respiratory function in the upright working diver at 6.8ATA (190fsw). Undersea Biomed Res 1987;14(3):241-62
    RRR ID: 3091

    Quote Originally Posted by Simon Mitchell  View Original Post
    Derion T et al. Static lung load and posture effects on pulmonary mechanics and comfort in underwater exercise. Undersea Biomed Res 1992;19(2):85-96
    RRR ID: 2604

    More where these came from! :)



    Please check this out!

+ Reply to Thread
Page 3 of 3 FirstFirst 1 2 3

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts