Irene, I too had concerns prior to my December cataract surgery. My doctor also told me all would be fine. She was correct. I am referring to MAC and not the hernia problem. I had absolutely no problem at all, not during or after. The surgery went well, I continue to use my vest and nebulize. I too have a lot of sputum but again no problem with my eyes while clearing and coughing. My surgery was in the morning and my last air ways clearing was the night before. I omitted the morning session and resumed that evening. I was able to cough some sputum out without the use of vest.
Good luck and by the way the only problem I actually had after surgery was seeing how dirty my house was along with all my new “face wrinkles “. 😂