What would happen if the pleural cavity was punctured underwater?

I'm just doing a little research. In a story I'm writing, a character is practicing water resilience techniques off the coast of an island. Accidentally, she crushes her ribcage on a sharp stone and one bone shrapnel punctures to pleural cavity, letting water enter and thus, collapsing the lung. She cannot make it to the surface in time to breathe and drowns. I know, it's a little far-fetched, but is it possible? Thanks, and you have a good one!