Age

[BILLB]

This is a basic question about the possibility of an AGE in four feet of water. On the surface this seems a bit extreme but my training agency states this as fact and I present it as fact in my classes.
The question is this: Under what circumstances is an AGE a possibility at four feet. Does the the victim have to have some other condition to make this happen? Or, are our lungs really that fragile?

 

[Dr Deco]

Dear BILLB:

Shallow-water Embolism

Strange as it sounds, it is possible to suffer arterial gas embolism from pulmonary barotraumas in as shallow as four feet. There are two cases on record of which I am aware.

The first involved some children who had inverted a tub underwater and were breathing from the air pocket inside. The story does not have a happy ending for the youngster who took a deep breath and held it the four feet to the surface. It never regained consciousness and was treated for what was thought to be drowning.

The other had a better ending. In practicing “ditching” of a helicopter in pool water, a crewmember breathed from an underwater breathing supply and held his breath the short distance to the surface from the simulator. Even this four feet was sufficient with a full lung of air to cause a rupture.

Fragile

Surprising as it might seem, lungs are quite fragile in this aspect. They were not made to be blown up similar to a balloon. Pressure is normally applied to the lung tissue by the diaphragm and the chest muscles and the lung is squeezed. If the lungs are pumped from the inside, the chest will expand along with the diaphragm and the lungs will inflate beyond their mechanical capacity.

Never hold your breath, is the prime directive in SCUBA. :nono:

Dr Deco :doctor:

Readers, please note the next class in Decompression Physiology :grad:
http://wrigley.usc.edu/hyperbaric/advdeco.htm

 

[BILLB]

Thanks! Examples like this will make presentations even more vivid to the diving students.