Gamow Bags for Altitude Diving?

[otter-cat]

Hi, Dr. Deco -

Do you think it could be effective to use a Gamow bag to aid a patient suffering from DCS after an altitude dive, while waiting for emergency services to arrive, and during transport to a recompression chamber facility?

I know that Gamow bags cannot achieve pressures even close to those experienced by divers underwater, but since in-water recompression is generally impossible in a recreational diving situation, could use of a Gamow bag at the surface have any potential to improve the situation for someone suffering DCS while they wait for full care?

I am thinking specifically about altitude dives that I do at about 7000 - 8000 feet above sea level. However, I also wonder whether a Gamow bag (or a similar device designed for higher pressure environments) could be successfully used in the ways I mentioned above, but at sea level.

Any thoughts or information you have about Gamow bags being used as an on-site treatment for scuba DCS at various altitudes would be very much appreciated.

Thanks,
otter-cat

 

[pasley]

...
Any thoughts or information you have about Gamow bags being used as an on-site treatment for scuba DCS at various altitudes would be very much appreciated...

You have an intersting subject here. I know they do make collapsible, portable decopression chambers. Not sure if the Gamow bag would generate adequate pressure. The below models are made to do the job.

http://www.sub-find.com/chambers.htm

http://www.nautilussystems.com/chambers/chamber-frame.htm

 

[Dr Deco]

Hello otter-cat:

Gamow Bag

The basic problem with the Gamow bag with respect to decompression sickness is its limited over-pressure capability. When treating mountain sickness, a small increase in pressure can readily change the course of the disorder. However, in the case of DCS, small pressure increases are not usually of much benefit.

Portable Hyperbaric Chambers

These are flexible chambers that can be inflated on site. They do not require a great deal of storage space although even a little required room can be consequential on a small boat. There are considerations of flammability if the bag is inflated with oxygen (and carbon dioxide scrubbing), or the placement of a mask if such is provided for the patient (and a very adequate oxygen supply). It is not easy to check vital signs nor can one easily administer medicines, since the patient is alone in the chamber. :doctor:

Dr Deco :doctor:

 

[fdog]

Once a bubble has formed, it takes a lot of pressure to squish it back down to nothing, and provide relief.

The 1 ATA or so of a mountaineering bag isn't enough. In the limited number of DCS treatments (3) I've done in a chamber, it seems the patient usually had relief at about 70-100'.

All the best, James

 

[otter-cat]

Thanks for the responses!

I have another question. One of the places that I dive sometimes is Crater Lake National Park in Oregon. It is a somewhat unusual dive site, in that the lake surface is at about 7100 feet above sea-level, however, the lake is in a caldera (crater at the top of a volcano), the top of which is around 8100 feet (or maybe the lake is at 6100 feet and the caldera top is at 7100 feet - I forget which.) To exit the lake area, you MUST ascend to the top of the caldera. Which means that even in cases of DCS, there is no way to avoid acending in altitude to reach treatment. In severe incidences of DCS, this would presumeably be by helicopter.

Do you think that in the admittedly uncommon situation I have described, a Gamow bag might be of use to avoid exacerbating the DCS during evacuation? Similarly, could it be of use during other helicopter evacuations, even from sea-level?

Thanks again for any opinions and information!

otter-cat