I was just making a joke for now. But the topic is well worth looking at. But:
FLOODING OF THE LUNGS WITH ANY KIND OF FLUIDS HAS TO BE CONSIDERED EXTREMELY DANGEROUS. SO DON'T TRY IT AT HOME.
there is several severe problems related with a flooding of the lungs:
-reflexes preventing fluids from getting into the airways
-hypoxia (not taken into account at the aspiration phase)
-hypoxia (decrease in oxygen delivery to vital tissues following a-phase)
-distress/anxiety (at least during aspiration) /effects on nervous system
-rupture of blood cells with to anemia (freshwater) /hypertonia
-pulmonary edema (salt water) /hypotonia
-pulmonary damage and subsequent hypoxemia
-unability to drain the flooded lungs
- etc etc.
The topic might have been discussed by freedivers, specialists and spectators of the film The Abyss. Sorry - I am not aware of any of these discussions. Let me post some thoughts for a lung filled 200m+ dive.
scenario 1:
-the apneist starts his nolimits dive as usual with full inhale/buccal pumping
-flooding of all airfilled spaces at a certain depth, e.g. -130m
(e.g 0.6l remaining airspace at this depth =600ml of seawater in his lungs)
-the apneist descents to -200m+
-he returns to the surface with the lift bags and inflates his
lungs by the use of his own respiratory musculature.
no laryngospasm occurs.
-enough oxygenisation from spontaneous breathing
or - enough oxygen stores remain for the first time (ok sign?)
-artificial respiration has to be applied to him with positive
pressure to provide reoxygenation and prevent drowning
or -the apneist recovers without artificial respiration
scenario 2:
-the apneist starts his nolimits dive with a forced exhale, neg. buccal
pumping followed by an intentional aspiration of 0.9% NaCl to completely fill
the lower airways
(when fluid goggles are fine for WR, why should fluid lungs be?)
-on the way down the apneist floods his upper airways with seawater
-the apneist descents to -200m+
-he returns to the surface with the lift bags and inflates his
lungs by the use of his own respiratory musculature.
no laryngospasm occurs.
-enough oxygenisation from spontaneous breathing
or - enough oxygen stores remain for the first time (ok sign?)
-artificial respiration has to be applied to him with positive
pressure to provide reoxygenation and prevent drowning
or -the apneist recovers without artificial respiration
A total amount of 600ml aspirated seawater may (I don't know it) not be fatal (equals a tolerance of 7.5ml seawater/kg bodyweight) although subsequent damage of the lung tissues may occur. An amount of 600ml isotonic NaCl would at least not damage the tissues. It may have a way better effect on post-dive recovery/reoxygenisation.
The idea of a reduced metabolism allowing to withdraw the O2-stores in the lungs by an intentional aspiration is as follows:
scenario 1: the diver at -130m is already undergoing bloodshift and bradycardia
scenario 2: the phyisiological changes are triggered by a forced exhale.
I consider the following limits to be significant:
- occurance of reflexes/anxiety -->laryngospasm --> high O2 consumption
- hypoxia (no residual O2-stores in the lungs!)
- post-dive recovery/hypoxia/damages to lung tissue
So, both scenarios could end up with an asphyxiated apneist.
Maybe most of you consider me crazy - maybe someone already prepares a 200m+ dive with a certain lungfill technique...
Yours Pat
