Shallow depth DCI

[DevonDiver]

I heard about a tourist that was taken on a Discover Scuba dive, to the maximum PADI guideline depth of 40 feet (12 metres), and was subsequently recompressed in the chamber with symptoms of DCI. I am surprised-what do you think.

12 meters is more than double atmospheric pressure...which means the body will on-gas substantially over time at depth. A DSD could last, what, one hour? That would mean a lot of inert gas absorbed...even though it was well within 'table limits'. However, in the holiday market, it is also quite possible that the DSD participant could be displaying several pre-disposing factors for DCI. Being overweight, severely dehydrated, hungover and possibly carrying an injury or other limitation to the cardio-vascular system can enable a DCI hit WELL WITHIN table limits.

I've heard of students getting evacuated from OW dives 1-2 for DCI recompression treatment - and this would essentially be the same dive as the 12m DSD....so this story doesn't surprise me.

 

[Prostar]

I had a chat with a nice lady from DAN at a show a few years ago. She said they have had a few reports of DCI from students in the pool at four feet.

 

[Nemrod]

Reports of are not the same as facts of. I don't buy it, the laws of physics are against it, the laws of partial pressure must be obeyed and to aquire enough nitrogen loading at a partial pressure sufficient to cause DCS is impossible at four feet. People can claim anything, I am sitting here with Big Foot at the moment having a beer and the likelyhood of either is about the same. Neither exist.

These people may be having an embolism, that is possible as we all know in very shallow water, but DCS, no. Let's look at this. Atmospheric pressure at sea level is approximately 15 psi (14.7 standard day). For simplicity sake let's take 30 feet in seawater as equal to one atmosphere (15 psi). At 30 feet seawater you will see a total pressure absolute of 30 psi. At four feet at .5 psi per foot you are only looking at an additional 2 psi. So at four feet your seeing 17 psi. A two psi differential is not enough to cause DCS.

N

 

[Scubadaddy]

I once heard about a guy who found and married a mermaid. PADI heard about it too...charged the guy $200 for the PADI underwater marriage course.

 

[String]

DDRC has at least 4 published cases in the last few years where it was definitely DCI and not embolism. They should know- they treat them.

 

[Jim Lapenta]

Reports of are not the same as facts of. I don't buy it, the laws of physics are against it, the laws of partial pressure must be obeyed and to aquire enough nitrogen loading at a partial pressure sufficient to cause DCS is impossible at four feet. People can claim anything, I am sitting here with Big Foot at the moment having a beer and the likelyhood of either is about the same. Neither exist.

These people may be having an embolism, that is possible as we all know in very shallow water, but DCS, no. Let's look at this. Atmospheric pressure at sea level is approximately 15 psi (14.7 standard day). For simplicity sake let's take 30 feet in seawater as equal to one atmosphere (15 psi). At 30 feet seawater you will see a total pressure absolute of 30 psi. At four feet at .5 psi per foot you are only looking at an additional 2 psi. So at four feet your seeing 17 psi. A two psi differential is not enough to cause DCS.

N

Better watch that big foot statement buddy. I've got an 8 foot hairy looking guy out in my backyard from time to time that might disagree with you. Wait there he is now! Hey c'mere. Oh forget it. It's just the neighbors mother in law scrounging for leftovers. Big ol beasty hog she is.

 

[captain]

DDRC has at least 4 published cases in the last few years where it was definitely DCI and not embolism. They should know- they treat them.

A may simply be the mindset of medical system to err on the side of caution. Someone comes in with symptoms that resemble DCI and has been diving. There is no clinical way such as xray, CT scan or MRI or other test to positivly determine it is DCI so they treat it as DCI and it goes on record as DCI. It could be if those same people went home and took a nap the result would be the same as the DCI treatment.

 

[Dadvocate]

All jokes aside, folks, this is a serious enough topic for quite a few people, especially those considering our sport or still wondering what happened to them when they thought they were within accepted limits.

I have a good friend who no longer dives because she got hit on a “typical” 18 meter dive. She came to the surface, started feeling poorly, the dive instructors and crew did a great job getting her on oxygen and to a doctor, and then later she went to a hyperbaric chamber a few times for treatment.

She is not one to point fingers and accepts that she is ultimately responsible for herself. No litigation came up at all for her. She paid the bill (no DAN) and then decided diving was done for her.

At the same time she is interested in better understanding how this type of thing happens, and what it was that made her more of a candidate for DCS than other people. She is healthy and active and wants to dispell the nagging suggesiton in her head that tells her she did something wrong and thus got DCS as a result.

If what she had was an embolism, would the treament have been the same, needing to require the chamber? If so, that could bring a lot of comfort to her. I ask this with only part of the picture of events given its second hand nature, but that isn’t really a crime in this thread as it seems.

Nonetheless, perhaps some of you could suggest ideas that might help her better understand what happened. She says DCS, but I think that might be reflective of her not really seeing an embolism as a possible, much more common source.


Cheers!

 

[Nemrod]

DDRC has at least 4 published cases in the last few years where it was definitely DCI and not embolism. They should know- they treat them.

They have an opinion, that is mostly what medicine is of this type. Thats is why when you have serious medical problems you should wisely get multiple opinions--opinions. My opinion as a scientist is he/they are wrong. Otherwise people would be getting bent taking a day hike to the top of a mountain for the view. It is just not a reasonable thesis.

There are various reasons some individuals may be more prone to DCI than others, those people should take up another sport. Even for an individual it might vary day to dsay and over time. If your getting bent in less than 30 feet of water after short immersion times you definitly need to go to golf or skateboarding or something, not diving.

I don't believe in little green men, big foot, moth man, ghosts, flying saucers, Bermuda Triangle, energy vortexes, elves, Atlantis, fairys or DCI after a four foot dive, sorry.

N

 

[tridacna]

I don't believe in little green men, big foot, moth man, ghosts, flying saucers, Bermuda Triangle, energy vortexes, elves, Atlantis, fairys or DCI after a four foot dive, sorry.

N

Add chiropractors, god and homeopathy to that list and I'm covered too.