I just thought it might be helpful to explain about airway hygiene for those who have Bronchiectasis. Everyone produces mucus secretions but normal lungs process it and you are not aware of it. My Pulmo explained that when you have Bronchiectasis your airway secretions do not work normally and so you have to do other things to compensate (nebulize saline, Aerobika, vests, positions, methods of breathing etc). But those things will still never be as effective. The lung hygiene helps to prevent mucus build up that breeds various bacterias. Since Bronchiectasis is not considered curable you will have to use these aids to airway clearance always. If you do not have Bronchiectasis but you do have MAC then some of this would not apply. Good questions for a Dr who specializes in MAC. No matter what, it must be good to get the mucus out and discourage the MAC with the saline. At least this is my understanding.