Agonal gasps..

Agonal gasping (in the context of Basic Life Support) is a condition in which the victim of cardiac arrest has occasional (perhaps once every 10 seconds) 'gasping' breaths.  This breathing pattern is usually accompanied by a snoring type sound, and perhaps a slight shrugging of the shoulders. 

To oversimplify-

When a healthcare provider shakes a victim ("hey, hey, are you ok?"), they should also... (read more here..http://www.carpentercprsolutions.com/-blog/agonal-gasps)