Snorkeling Barotrauma?

[H2Andy]

http://www.scuba-doc.com/pfo.htm

I hope one of our board member doctors chime in but it may be possible your son has a pfo and should be tested before he does any more diving, free or scuba.

he might and he should ... but i don't think this was a factor here.

a PFO (patent foramen ovale) can lead to passage of bubbles into the arterial
circulation (rather than venous circulation) which means the blood containing bubbles goes across the PFO into the arterial circulation and the usual filtering process of the lungs is by-passed.

that's not what it sounds like here