Woman dead, husband injured on 230 meter dive - Greece

[fsardone]

Exactly, as Laura surmises, way more likely a so-called inner ear 'bend'. And VERY nasty business that from what I know from those that have experienced it / survived it.

Anything that has to do with ear is very very nasty.
A buddy of mine had a bad issue with middle/inner ear while on a relatively shallow dive (60 mt, wreck of Loredan in the gulf of Cagliari).
Once down on the wreck he was unable to stay in trim and started thumbling around. It could not be an inner ear bend since it happened once reached the bottom. He had no issue equilibrating on the way down.
Fortunately the wreck has a permanent shot line (12 mm or half inch) and by guiding him on the way up we were able to complete deco.
He had to be dekitted and almost lifted out of the water.
beside hanging to the shot and rising when I told him to and switched gas when I told him to, he was completely non functional and he his a better diver than I am. He was (we were) lucky there was no vomiting involved.
His ENT specialist found a nasty infection which has thinned the ear drum and he believes my buddy suffered a slow water entry, which filled the middle ear creating sensorial issues. He has been off diving for more than 12 months before starting again in rec depth ranges.
Bottom line an ear issue without third party support, in my view, is not (easily) survivable. A very good reason for not diving solo (I am solo cert and sometime I do ... so no judgment involved here)

 

[Tuscany]

One general question tho - 230m and 5h30m dive sounds a bit tight to me? Isn't this a bit non-conservative?

 

[fsardone]

One general question tho - 230m and 5h30m dive sounds a bit tight to me? Isn't this a bit non-conservative?

It is.
Using a fast hack with VPM, I get 500 minutes even using 6 or 7 deco gasses. I would not recommend to plan such dive with VPM, Bulmhan with GF will increase the shallow time way more than I have got with VPM.

A 230 mt bounce (not that I have direct experience, I just read it in books about Exley) should not last less than 7-8 hours ... and this is also confirmed by current planning software.

Cheers

 

[oceancurrent]

It does look like people have bounced to these depths on one breath without any deco stops whatsoever (AIDA freediving World Records | Freedive Earth).

 

[Dan]

Free diving is totally different physical condition where the free diver lung shrinks to the size of apple by the time the diver reaches that depth, while scuba diver would maintain the same size of lung as before.

 

[rossh]

One general question tho - 230m and 5h30m dive sounds a bit tight to me? Isn't this a bit non-conservative?

Using all the fastest tricks to minimize time, its about a 5 or 6 hour dive. (13 second bottom time, sped up descent / ascent rates). But that kind of short cutting has zero margin for delays or deviations. example: Deco time accumulates at 40 mins per extra minute at the bottom. A realistic plan would include margins for small errors.

.

 

[Kay Dee]

It does look like people have bounced to these depths on one breath without any deco stops whatsoever (AIDA freediving World Records | Freedive Earth).

Free diving is totally different physical condition where the free diver lung shrinks to the size of apple by the time the diver reaches that depth, while scuba diver would maintain the same size of lung as before.

Well, besides, the freediver takes his / her 'gas' (i.e. a lungful of air) from the surface with him / her, while the deep scuba / ccr diver takes his with him on his / her back and is continually saturating his / her tissues breath-after-breath the deeper he goes / the longer he stays at the inceased pressurse of depth. A very very different kettle of fish (as opposed to a free diver)!

 

[TrimixToo]

...which prevents oxygen from binding and reducing the amount of oxygen being carried by the hemoglobin. It is the lack of oxygen being delivered to the tissues that causes the problem--the CO by itself does not cause tissue damage.

However, at those depths, the plasma in the blood often carries enough oxygen to overcome that. This allows more oxygen to get to the tissues. Additionally, the presence of the excess oxygen helps undo the chemical reaction of the CO binding to the hemoglobin. As the diver ascends, the PPO2 generally decreases, lessening that benefit. However, when a trimix diver ascends and switches gases, that switch usually creates a greater O2 partial pressure than the diver had during the working part of the dive, thus restoring the high oxygen environment.

treatment for CO poisoning is usually breathing pure oxygen. Hyperbaric oxygen treatment is also used, although the benefits of that over just breathing oxygen are inconclusive.

At last year's BTS, Dr. Sotis explained that at higher ambient pressures, sufficient O2 dissolves in the blood plasma to support the body's needs without any hemoglobin transport at all (with the numbers to show it). IIRC, this is linearly proportional to depth. However, as one ascends, the amount of dissolved O2 decreases, and one depends to a progressively greater extent on hemoglobin transport. Thus, CO problems often present on ascent even though we normally change to progressively higher PPO2 as we go. The higher PPO2 cannot compensate for the lower ambient pressure, the O2 reaching the tissues drops, and you pass out.

She also said the dissolved O2 in plasma is why hyperbaric treatment is the reason it's effective in treatment. Since 100% O2 cannot compensate for CO-saturated hemoglobin, it is apparently the treatment of choice in her view.

 

[cerich]

At last year's BTS, Dr. Sotis explained that at higher ambient pressures, sufficient O2 dissolves in the blood plasma to support the body's needs without any hemoglobin transport at all (with the numbers to show it). IIRC, this is linearly proportional to depth. However, as one ascends, the amount of dissolved O2 decreases, and one depends to a progressively greater extent on hemoglobin transport. Thus, CO problems often present on ascent even though we normally change to progressively higher PPO2 as we go. The higher PPO2 cannot compensate for the lower ambient pressure, the O2 reaching the tissues drops, and you pass out.

She also said the dissolved O2 in plasma is why hyperbaric treatment is the reason it's effective in treatment. Since 100% O2 cannot compensate for CO-saturated hemoglobin, it is apparently the treatment of choice in her view.

was her assertions peer reviewed?

 

[Dan]

Well, besides, the freediver takes his / her 'gas' (i.e. a lungful of air) from the surface with him / her, while the deep scuba / ccr diver takes his with him on his / her back and is continually saturating his / her tissues breath-after-breath the deeper he goes / the longer he stays at the inceased pressurse of depth. A very very different kettle of fish (as opposed to a free diver)!

I guess I didn't state my post clearly enough. Free diver uses the same air volume from atmospheric pressure down to the bottom. So, if the bottom pressure is 10 atmospheres (90m depth), then his / her lung volume would be closed to 10% of it at the surface. That's what I meant by "shrinks". So, going back to the surface without stopping would not be a problem. His or her lung just returns to normal volume.

Scuba diver will maintain the same lung volume at depth & surface. That's why we need to be careful ascending to avoid AGE (blowing the lung up like a balloon).

For those who like deep sea fishing, you will notice those cods would float like balloons by the time you reel them to the surface faster than the fish can bleed out their swim bladders. I remember the boat crew had to poke its belly & let the fish go when it was not a legal size for keeping.