First, so glad your Mom is doing better! I work at a hospital and hearing success stories is awesome! All too often, we only hear of the bad experiences. I hope your Mother continues to do well!
For a more lasting gift - how about a Keurig & assorted K-cups for the lounge. A gift that would last a long time, and I'm sure get a lot of use. When your K-cups are gone, they can always get more. Even if they already have one, having two would be great!
Very nice of you to make the gesture. I also agree with previous posters about sending a note to the nurse manager individually naming those who were particularly special to you and your Mom. Our hospital gives special recognition as well.