When the patient exhales into the device, a ball bearing creates vibrations that travel back into the lungs and loosen the mucus. This triggers the patient to cough, which helps to remove the mucus.
The small, portable device can help clear mucus in conditions such as cystic fibrosis, bronchiectasis and COPD. It is usually used for 5–15 minutes at a time.
Flutter must not be used in patients with right-sided heart failure, pneumothorax, TB or haemoptysis.