Most of us have seen an MBS report that recommended a thick liquid due to “risk of aspiration” on thin, or penetration on thin… or both…but IS penetration ALWAYS a bad thing? Multiple studies have shown that plenty of healthy, normal people penetrate. During the development of the Penetration-Aspiration scale, 95 healthy subjects demonstrated a total of 55 penetration events. All penetration during this study was scored at a 2 or a 3 (2 meaning that the penetration stayed above the vocal folds and was then expelled, 3 meaning that the penetration went to the same depth, but that there was residue in the laryngeal vestibule after the swallow).
In a study by Dagget et al, penetration was noted in 16.8% of swallows in individuals over the age of 50. It’s also important to know that a cough would NOT be an expected response to penetration, given that innervation to the hypopharynx is provided by the internal branch of the superior laryngeal nerve-which doesn’t trigger a cough response. So citing “silent penetration” or residue in the airway vestibule after penetration shouldn’t be a reason given for increased “risk” with penetration.
Confession time: here is a lovely swallow of.. myself! In which I penetrate on repeated swallows of thin liquid. I actually had no idea that I penetrated until I watched the replay. I still can’t decide if I’m proud or a little embarrassed of myself.
See links below for further reading!!