Finnish diver missing in Swedish mine

[TONY CHANEY]

The team climbed the ladder up to about 6 to 7 meters deep and headed for the Rabbit Hole. After diving for about 28 minutes, diver 1 started began moving into the about 2 meters in diameter Rabbit Holen, diver 2 to the place behind him and provided light. Diver 3 was next to Diver 2, behind and at a diagonal. When diver 1 had gone about two feet, he suddenly began to back up, using hands, pushing heavily. As he reached the mouth opening, diver 2 noticed that there was air in the feet of diver 1, but the legs had not risen to the ceiling of the corridor. He noticed that everything was not OK when the diver 1 kicked with the legs all the time without the kicks being effective.

The team is entering a restriction of about 6' in diameter. By all means, not the tightest of restrictions but with back mounted doubles it can be a little tight. I am by no means speaking for the entire cave diving community, but I was taught to always dump any excess air from the BCD as well as the dry suit before entering a major restriction. I believe that this team would have also known this. This is why I suspect that the dry suit was self inflating thus making it impossible to to advance past the restriction. (You see a lot of cave divers with the dry suit dump valve on the forearm). Now you are stuck in a restriction and without any way to dump excess air from the suit. Now you try to kick but the fins are not on your feet. Here is where the diver begins to use his/her hands backing up "pushing heavily." This is not fairy fanning or sculling. This is grabbing the rock formations and pushing like heck to get out of the restriction. So now we have a team about 1312' back in a cave, one diver just appeared to have gotten stuck in a restriction and now once freed has lost their fins and this in taking place in about 20" of vis. After that, your guess is as good as mine.

OBTW, please stop using Metabolic acidosis. Metabolic acidosis is a severe lost of HCO3 and not an increase or decrease in CO2.

This place is amazing!

 

[Kevrumbo]

. . .OBTW, please stop using Metabolic acidosis. Metabolic acidosis is a severe lost of HCO3 and not an increase or decrease in CO2. . .

It is NOT Respiratory Acidosis symptomology as in chronic pulmonary lung disease that is the primary pathophysiologic genesis here, but rather the special case of acute Hypercapnia in Diving (or pathological CO2 Toxicity in an immersed hyperbaric environment).

As a Respiratory Therapist yourself: Do you understand @TONY CHANEY ?

. . .Rising blood CO2 (‘hypercapnia’) is a problem in diving for several reasons. In particular, high CO2 can produce symptoms such as headache, shortness of breath and anxiety. At very high levels these symptoms might lead to panic and drowning. Collectively, these manifestations are often referred to as ‘CO2 toxicity’. The second reason high levels of CO2 are a problem in diving is that CO2 can precipitate other diving-related problems. In particular, CO2 is a narcotic gas and high CO2 levels will substantially worsen nitrogen narcosis. Similarly, high levels of CO2 are known to significantly increase the risk of cerebral oxygen toxicity, which can manifest as a seizure with little or no warning. The mechanism for this is probably that high CO2 levels cause a substantial increase in blood flow to the brain, thus increasing the brain’s exposure to oxygen. . .

". . .To give you some sense of the small changes in arterial blood levels required for these phenomena, PCO2 around 5kPa is the average normal level, 6.2kPa is the upper limit of the normal range, and over 8.5kPa sudden incapacitation is likely. Experiments show that levels between 6.5 and 7.5 are not uncommon in divers working underwater. The point is that small changes in PCO2 of 1kPa or less can have very important implications for the safety of the diver. . ."

. . .This normal process of CO2 control can be disturbed in diving because of an increase in the work required to breathe. The work of breathing increases because we are respiring a denser gas through a regulator or rebreather. CO2 retention is a pathophysiologic condition in Scuba diving in which we are not ventilating efficiently enough to eliminate the CO2 we are producing. The more the work of breathing increases (e.g. because we are deeper breathing a denser gas like Air or Nitrox), and the more CO2 that is being produced (e.g. because of exercise) then the more likely CO2 retention/build-up is to occur because we cannot expel enough of it, and the vicious cycle quickly spirals out of control into acute Hypercapnia. . .

Advanced Knowledge Series: The Gas Density Conundrum | Dive Magazine

See also 4:00 mark in the video below about CO2 in the context of diving:

 

[TONY CHANEY]

Acute it the fundamental word. Metabolic acidosis is not an acute situation. If a person was throwing up, not eating and had a severe case or diarrhea over several days then yes metabolic acidosis is very likely. Thanks for the "Respiratory Failure in Technical Diving" which I truly enjoy and have watched in several times in the past. It also has nothing to do with Metabolic acidosis. Thanks for sharing my Respiratory Therapist Credentials and proving my point.

 

[Kevrumbo]

Acute it the fundamental word. Metabolic acidosis is not an acute situation. If a person was throwing up, not eating and had a severe case or diarrhea over several days then yes metabolic acidosis is very likely. Thanks for the "Respiratory Failure in Technical Diving" which I truly enjoy and have watched in several times in the past. It also has nothing to do with Metabolic acidosis. Thanks for sharing my Respiratory Therapist Credentials and proving my point.

IMHO my friend, it's not only about moderating Nitrogen Narcocsis, but also preventing high CO2 levels as well: instead of Nitrox 27 to 29% at 36m depth average, a 25/25 mixture of O2/He Triox could have lessened the gas density and improved work-of-breathing margin enough to moderate exercise CO2 retention from developing into acute Hypercapnia.

Cause of Death: Drowning.
Manner of Death: Accident. Rule Out Acute Hypercapnia as precipitating pathology, with possible secondary Oxygen Toxicity Syndrome & Convulsions.

 

[TONY CHANEY]

Dr Mitchell is talking about the density of a gas at great depths. Here the MAX depth was 36 meters and then they “climbed the ladder” to about 30 meters. No one I know of dives 90 feet on trimix just to lower gas density. And again it has absolutely nothing to do with metabolic acidosis.
Why can’t you just say I made a mistake and said metabolic when you meant to say respiratory.

 

[Kevrumbo]

Dr Mitchell is talking about the density of a gas at great depths. Here the MAX depth was 36 meters and then they “climbed the ladder” to about 30 meters. No one I know of dives 90 feet on trimix just to lower gas density. And again it has absolutely nothing to do with metabolic acidosis.
Why can’t you just say I made a mistake and said metabolic when you meant to say respiratory.

Not necessarily a gas density at great depths per se. Indicative of frank CO2 retention, the exhaled threshold metric of 8.5 kPa PCO2 with exercise is at a breathing gas density of over 6 g/L, which coincidentally happens to be the recreational depth limit for Air at 40m. In this case, with EANx28 at max depth 36m, the gas density is 5.57 g/L which is getting close to gas density threshold. The victim could have been just a normal functional physiologic "blue bloater" CO2 retainer, but easily overcome with the physical activity and hyperbaric immersion stressors of this particular dive. See again: Advanced Knowledge Series: The Gas Density Conundrum | Dive Magazine

 

[TONY CHANEY]

Ok my Respiratory Therapist credentials are on the table. What are your credentials? I am so done with this sideways conversation. This is pure BS!

 

[Kevrumbo]

Ok my Respiratory Therapist credentials are on the table. What are your credentials? I am so done with this sideways conversation. This is pure BS!

Just a regular hypercapnic Scuba Diver -as we all are- to a degree:

. . ."Normal respiration in divers results in alveolar hypoventilation resulting in inadequate CO2 elimination or hypercapnia. Lanphier's work at the US Navy Experimental Diving Unit answered the question, "Why don't divers breathe enough?"

http://archive.rubicon-foundation.o...le/123456789/3327/NEDU_1956_02.pdf?sequence=1
http://archive.rubicon-foundation.o...le/123456789/3362/NEDU_1958_07.pdf?sequence=1
http://archive.rubicon-foundation.o...ndle/123456789/3809/NEDU_56_05.pdf?sequence=1

The lesson learned from this unfortunate event is simply to follow the PADI mantra:
STOP. BREATHE. THINK. ACT.

 

[Kevrumbo]

Panic and the Hypercapnic Alarm Response

 

[BoltSnap]

The lesson learned from this unfortunate event is simply to follow the PADI mantra:
STOP. BREATHE. THINK. ACT.

This isn't something specific or originated by PADI.