A person with bronchiectasis has damaged bronchioles, so the action of the bronchiole and the cilia inside are impaired, and normal breathing and coughing are not enough to expel mucus from the lungs. Accumulated mucus is the ideal dark, warm moist, nutrient-rich environment for the growth of bacteria, leading to opportunistic infections like pseudomonas and the dreaded MAC.

Acapella, and its companion Aerobika are vibratory devices, with a flutter valve, that are used to loosen mucus in the lungs so coughing can expel them. A particular cough, known as the "huff cough" is most effective. The device is often used after a session with a nebulizer, typically containing albuterol or saline to open bronchioles and thin the mucus. Or sometimes after using an inhaler. People with more severe bronchiectasis, or who are unable to bring up mucus are sometimes prescribed a percussion vest instead.

When you were diagnosed, did anyone show you how to use the Acapella, or suggest use of an inhaler or nebulizer? If not, here is an excellent explanation and demonstration: https://www.youtube.com/watch?v=sAVQ6CFuNUM
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