Three dead and one in recompression chamber in Italy, Tuscany

[DandyDon]

LOL more speculation by totally unqualified people, it wasn't CO if it had been, the survivor would not have improved from recompression and he would have gotten worse and died.

I think the lack of knowledge here has been well established. Thanks for playing.

 

[2cold4california]

I think the lack of knowledge here has been well established. Thanks for playing.

We will see who the fool is when the report comes in, you say (with absolutely zero evidence besides the presence of a fatality) that's it's CO. I say uncontrolled ascent and resultant DCS/embolism.

It really speaks poorly of the board that people like posts like yours.



Re: Lecter I agree it would help in a band-aid way but that man would need blood transfusions if it was CO which a recomp chAmber makes problematic.

---------- Post added September 4th, 2014 at 02:46 PM ----------

Why then would hyperbaric oxygen therapy be used in the treatment of CO poisoning.

It isn't. Not in the most severe cases.




Thanks

 

[Dr. Lecter]

We will see who the fool is when the report comes in, you say (with absolutely zero evidence besides the presence of a fatality) that's it's CO. I say uncontrolled ascent and resultant DCS/embolism.

Did you not read the linked news articles? Presence of CO in the tanks from a specific supplier has been confirmed; I seriously doubt they're just making up the specific readings (1600ppm-2400ppm across the four tanks) cited therein. Sub morti, nelle bombole monossido di carbonio fino a dieci volte più del consentito | Umbria24.it Sub morti, c?è un altro indagato. Il monossido anche in altre bombole: grave malore per un quarto uomo | Umbria24.it

 

[2cold4california]

Did you not read the linked news articles? Presence of CO in the tanks from a specific supplier has been confirmed; I seriously doubt they're just making up the specific readings (1600ppm-2400ppm across the four tanks) cited therein. Sub morti, nelle bombole monossido di carbonio fino a dieci volte più del consentito | Umbria24.it Sub morti, c?è un altro indagato. Il monossido anche in altre bombole: grave malore per un quarto uomo | Umbria24.it

At those cited concentrations at depth they all should be dead

 

[fire_diver]

If everybody died when they "should be dead", we would have a lot few people in the world. I have seen people die from seemingly non life threatening injuries and I have seen people in accidents just don't look like much. What happens in the human body is still a mystery some times.

 

[grf88]

We will see who the fool is when the report comes in, you say (with absolutely zero evidence besides the presence of a fatality) that's it's CO. I say uncontrolled ascent and resultant DCS/embolism.

It really speaks poorly of the board that people like posts like yours.



Re: Lecter I agree it would help in a band-aid way but that man would need blood transfusions if it was CO which a recomp chAmber makes problematic.

---------- Post added September 4th, 2014 at 02:46 PM ----------



It isn't. Not in the most severe cases.




Thanks

Making a categorical statement when ill informed is one thing. Repeating it after being given the opportunity to examine the facts is downright...... To be polite I will let others fill in the rest.

 

[DandyDon]

We will see who the fool is when the report comes in, you say (with absolutely zero evidence besides the presence of a fatality) that's it's CO. I say uncontrolled ascent and resultant DCS/embolism.

Have you not bothered to read the whole thread, all posts? I don't think I mentioned CO at all until the initial reports said it was found in the tanks. Actual evidence is not available to us here, but the reports do say CO.

Sub morti, c?è un altro indagato. Il monossido anche in altre bombole: grave malore per un quarto uomo | Umbria24.it

the news said: carbon monoxide in almost all the tanks filled and used that day.
in the same day a forth diver survived from a tank with 2300 ppm of carbon monoxide.,

the three divers got 2400. 2100, 1600 ppm.

:-(

I am curious about those numbers, and we are discussing reports translated from Italian. It's also easy to get confused about decimal placement, percentages vs ppm, etc.

Why then would hyperbaric oxygen therapy be used in the treatment of CO poisoning.

It isn't. Not in the most severe cases.

I checked your profile for medical credentials? I see "Experienced Diver" with more than 10 years diving, less than 100 dives, but I don't see any mention of you being a physician or having other training that might support your claims.

The most common treatment for CO poisoning is oxygen therapy, preferably HBO - altho there still is controversy about whether HBO helps or not. See Carbon monoxide poisoning Treatments and drugs - Diseases and Conditions - Mayo Clinic

Blood transfusions for CO poisoning is not commonly mentioned, altho it is an option. Excerpting from https://www.uam.es/departamentos/medicina/anesnet/journals/ijeicm/vol1n2/articles/co.htm

Currently the Undersea and Hyperbaric Medical Society recommend HBO for those patients with signs of serious intoxication regardless of their COHB levels.⁵⁶ This includes patients with a history of unconsciousness, presence of neurological signs, cardiovascular dysfunction or severe acidosis. Pregnant women should be evaluated with liberal criteria for HBO due to the increased toxicity risk to the fetus In the absence of access to HBO therapy, severe poisoning should be treated with 100% oxygen, with endotracheal intubation in patients who cannot protect their airway. In these patients, consideration should be given to transfusion of packed red blood cells.⁵⁷

Anyway, the reports given to us so far say CO tainted tanks, and HBO was used on one diver who survived.

 

[iain/hsm]

At those cited concentrations at depth they all should be dead

If no one else will agree with you, allow me to be the first.

As well as building gas compressors I design and have supplied a number of diving chambers some of which have been used for the hyperbaric treatment of carbon monoxide poisoning.
Mainly these CO poisonings are either suicide attempts using car exhaust or by faulty gas heaters in mobile homes, caravans and the like.

When they arrive at the chamber most are pretty ill already and I suspect a factor in the low rate of recovery is in some part attributed to the chamber being the "last chance saloon" aspect these chambers offer.

However carbon monoxide CO in a cylinder used in diving is aggravated by the partial pressure depth effect of the dive. Air divers in UK commercially max depth is 165 FSW 50MSW 6 bar ATA
but practically mostly anything under 100fsw, 30msw is done on breathing air.

We also incidentally manufacture carbon monoxide compressors for the gas companies. Hence my interest in the safe human exposure limits.

From a breathing concentration of CO in say a workshop environment atmospheric gas perspective and to get the decimal point corrected.

At the surface your three divers cylinders had the following CO content:

Diver One: 2400ppm is 0.24% of CO at surface
Diver Two: 2100ppm is 0.21% of CO
Diver Three: 1600ppm is 0.16% of CO

I would also really like to see the full gas spec reports for each of the cylinders as this would at least allow us to speculate further the cause however

From a gas toxology position we have always used 4000 ppm or 0.4% as the lethal concentration for a 30 minute duration exposure at the surface to be a lethal dose

And here's the kicker at 5000ppm or a 0.5% CO concentration for a lethal dose the duration reduces to 5 minutes.

So at 36MSW depth these lads would be at nearly 5 bar ATA IMHO if the above figures I gave for lethal doses are about correct then I would have to agree with you they all should, yet thankfully are not. Iain Middlebrook


Adder.
I would add that the real kicker when faced with CO is that the lethal to say pleasurable range is remarkably close. CO sticks to the haemoglobin in the blood and its hard to release it.
One hour at 1000ppm is not dangerous, yet 1500 to 2000ppm over an hour would be.

To explain a medic would give a better explanation but in essence its the level of CO in the blood that is the critical aspect to measure. (not necessarily the percentage of CO in the breathed gas)

In essence Carboxhemoglobin COHb is the marker to measure.

30 minutes at 1200ppm will produce 10 to 13% COHb and all you get is a headache
at 30% COHb you begin to loose dexterity and at 40% COHB in the blood and your out of it.

Now a blood toxicity reading of COHb of the deceased blood, together with the CO ppm reading of his tank/cylinder, together with a download of his dive computer
and we could make some good quality detailed analysis of the narrow band of safety CO in a gas offers the breather.
And the simple and easy ways to avoid. Iain Middlebrook

 

[raftingtigger]

I'll start with a disclaimer. I do not read or understand Italian and my only info on this tragic accident is what is posted in this thread.

IIRC, 3 divers died, 1 was taken to a chamber, and several others reported feeling ill. One common factor was the source of the gas fills. There may have been other common factors, but they were not all buddies. Excessive CO was found in the dead diver's gas tanks.

CO poisoning has a dose/time relationship. The higher the concentration, or the longer the time, the more toxic it is. The concentration of CO is a function of what percentage is in the gas AND what pressure the gas is at. Or in simpler terms - the partial pressure of that gas. The higher the partial pressure, the less time before symptoms develop. Of course there are individual variabilities in a person's response to the same CO dose.

I do not recall any information (in English on this thread) that gives the ACTUAL depths, profiles, or exposure times for any of the divers involved. Without that information it is only speculation as to what the actual dose of CO any of the divers experienced.

Multiple divers, in different teams, but using the same gas fill source became ill. Some of these divers died. The deceased divers MAY have had a rapid ascent. A rapid ascent MAY (but by no means always) result in an AGE event. To have 4 (apparently highly experienced) divers suffer an AGE event at the same time doesn't sound reasonable. There is evidence of excessive CO in the tanks (I don't care if the decimal is in the right place) - this gives a very plausible explanation for multiple divers being affected. Therefore, I'm with DandyDon and am getting a CO tester.

Sensorcon has them back in stock. http://sensorcon.com/products/porta...pector-carbon-monoxide-tester-for-scuba-tanks I paid $169 + shipping and the sensor is good for at least 2 years.

 

[grf88]

I'll start with a disclaimer. I do not read or understand Italian and my only info on this tragic accident is what is posted in this thread.

Google translate can help you there.