What does a laryngeal mask provide?

sorry, I was cut off. LMA's maintain patency of the airway but also allow inhalational anesthetics to be administered.

Olly, If I had known the meaning before, I would have chosen the right answer according to the picture

Olly, not a word I was familiar with either. Related to some meanings of patent: clear, plain, unobstructed.

I wonder what "patency" means?