spontaneaous pneumomediastinum and scuba/free diving ?

[juju01]

Hello,

I want to ask if having a spontaneous pneumomediastinum more thant 10 years ago is blocking for diving (seems yes) and freediving (uncertain) ?

It's not a pneumothorax. It's air between mediastinum, pleura intact.

Thanks

More on:
Medscape: Medscape Access
http://www.cardiothoracicsurgery.org/content/3/1/59
Spontaneous Pneumomediastinum from Running Sprints

 

[cutlass]

Unexpected gas anywhere in the body is reason enough to stop diving activity until it is examined and risks are assessed. In this case, not only is barotrauma a concern but also the possibilities of cardiac arrhythmias, impaired breathing, and altered mental status due to abnormal displacement of mediastinal (chest) structures; i.e. heart, key blood vessels and nerves.

Since SPM most commonly begins with alveolar rupture from overpressure*, then there is a risk even for breathhold diving. A simple cough can give peak pressures around 50cm H2O which is generally above the limit of which alveolar injury is likely. Usually this kind of pressure spike is cushioned by normally less-than-full lungs, a reserve of chest wall excursion, and healthy, elastic lung tissue. But very full lungs as during a breathhold, or less than healthy lung tissue, might not so readily tolerate such a spike.

*"Volutrauma" as in this post .

 

[TSandM]

Air in the mediastinum had to get there from another air-filled thoracic space. Although it can occur as a result of rupture of the esophagus, those patients get horrendously sick, and it's unlikely you would be unaware of the source. More commonly, pneumomediastinum shares an etiology with pneumothorax -- a weakness of the wall of alveoli. In the case of PM, the air that escapes from the lung, instead of entering the pleural space (between the lung and chest wall), tracks along the bronchus and enters the mediastinum. It tends not to be as serious an acute problem, and in the vast majority of cases, requires no specific treatment. But it has the same implications of anatomic abnormality as PTX.

Because of the potential lethality of pneumothorax underwater, I remain of the opinion that people who have experienced spontaneous pneumothorax should not scuba dive, and it would be my position that spontaneous pneumomediastinum would be no different. I don't really think free diving would run a significantly higher risk than exercise on land. If you did suffer a rupture underwater, the air in your lungs would still only be at 1 ATA, so there would be no risk of tension physiology.

 

[TSandM]

A correction, thanks to one of our fellow SB members: The air in the lungs was inhaled at 1ATA. It will, of course, come close to or equal ambient (depending on the degree of chest wall collapse) at depth, while freediving. But on ascent, it will not expand beyond the original volume inhaled at 1 ATA, so tension physiology is not a risk.

 

[juju01]

Thanks for all your feedback.

Summary:
* diving NOK
* freediving OK, without any special constraints (depth, length or others)

For the archives, the incident occurs fifteen years ago (on land) and current condition is completely normal without any trace.

Thanks everyone !