Dr Deco
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Hello readers:
Flying after Diving :umnik:
There are various safety recommendations based on the expected dissolved nitrogen (tissue gas) elimination. This is a very general concept and can lead to difficulties in a few instances.
Naturally we are assuming that the 18-hour rule is safe since we are not discussing decompression diving. Multiple dives over multiple days could likewise lead one to treat the interval more conservatively.
Not an Exact Science :doctor:
I could get some argument from my fellow research barophysiologists on this - but not many. It might surprise people to know how repeatable decompression bubble formation is under laboratory conditions. Diving in the field is not a laboratory-controlled environment. Exercise and rest conditions vary considerably, as well as gas loads. In addition, one does not know their individual level of susceptibility to gas bubble formation.
Thus while we have some degree of repeatability, for a population of tens of thousands of divers, it is really like a well-mixed deck. You deal the hand and everyone is random.
Dr Deco :doctor:
Readers, please note the next class in Decompression Physiology is September 10 11, 2005 :1book:
http://wrigley.usc.edu/hyperbaric/advdeco.htm
Flying after Diving :umnik:
There are various safety recommendations based on the expected dissolved nitrogen (tissue gas) elimination. This is a very general concept and can lead to difficulties in a few instances.
- Not all people have similar uptake and elimination rates. This is dependent on heart rate and activity level [that largely determines blood flow in extremities].
- Dissolved nitrogen elimination will be slowed if it enters the gaseous (in bubbles) state. This will occur if there is strenuous activity, e.g., hauling heavy dive gear after the dive and later heavy luggage.
- Hydration is important, since it plays a role in tissue perfusion [blood flow]. It probably also influences the surface tension of the tissue fluids. Low surface tension [from dehydration] is undesirable, since it will stabilize tissue gas bubbles once they are formed.
- Sleep following the dive is not particularly desirable since it reduces the tissue blood flow to its lowest level. It is better to remain awake and mildly active for the first few post-dive hours.
- Resistant and DCS-susceptible divers exist. If you are not aware that you are very resistant, I would treat myself as a susceptible diver and decompress accordingly. [All laboratories that test tables know who are the susceptible members of the dive test-team. They are the canaries and are the acid test of any decompression scheme.]
Naturally we are assuming that the 18-hour rule is safe since we are not discussing decompression diving. Multiple dives over multiple days could likewise lead one to treat the interval more conservatively.
Not an Exact Science :doctor:
I could get some argument from my fellow research barophysiologists on this - but not many. It might surprise people to know how repeatable decompression bubble formation is under laboratory conditions. Diving in the field is not a laboratory-controlled environment. Exercise and rest conditions vary considerably, as well as gas loads. In addition, one does not know their individual level of susceptibility to gas bubble formation.
Thus while we have some degree of repeatability, for a population of tens of thousands of divers, it is really like a well-mixed deck. You deal the hand and everyone is random.
Dr Deco :doctor:
Readers, please note the next class in Decompression Physiology is September 10 11, 2005 :1book:
http://wrigley.usc.edu/hyperbaric/advdeco.htm
