The Lung Flute - An Acoustic Device for Airway Clearance

Original Editor - Arnold Fredrick D'Souza Top Contributors - Arnold Fredrick D'Souza and Kim Jackson

Introduction[edit | edit source]

The Lung Flute is a handheld positive expiratory pressure therapy device that uses sound waves to mobilize and clear secretions. It is tubular with a plastic mouthpiece at one end which is attached to a Mylar reed that flutters during use.[1]

Mechanism of Action[edit | edit source]

The Mylar reed is flared on the other end to increase the air mass within the device. This provides acoustic impedance. When the device is being used, the Mylar reed will oscillate at a frequency that matches the resonance frequency of pulmonary secretions (16-25Hz). Thus, the viscosity of these secretions is reduced by mechanical vibrations resulting from the sound waves. Additionally, these vibrations will also facilitate the action of the mucociliary escalator system, which will mobilize the loose and thin mucus, to ensure optimal bronchial hygiene by easier and more effective expectoration.[1]

Method of Use[edit | edit source]

The following steps[2] will ensure the correct use of the device:

  • First, perform a deep inhalation. Then, place lips around the mouthpiece. Exhale forcefully through the Lung Flute® as if trying to blow out a candle. After that, remove the mouthpiece and quickly inhale again. Now, put the mouthpiece back in the mouth, and blow gently through the Lung Flute.
  • Remove the mouthpiece again and wait 5 seconds, taking several normal breaths.
  • For best results, blow into the Lung Flute® for up to 20 sets of two blows per set. (Begin slowly and build up the number of repetitions over time.)
  • Approximately 5 minutes after the session has ended, mucus will have collected at the back of the throat and vigorous coughing may occur. Thinned mucus may collect at the back of the throat for several hours after the session, which is normal. A drink of water will wash away the mucus and prevent minor throat irritation.


Indications[edit | edit source]

The Lung Flute® is indicated for the following conditions:

Evidence[edit | edit source]

Clinical trials have found the Lung Flute® to be a highly effective tool for bronchial toiletry.[8] It is equivalent to the Acapella in therapeutic efficacy.[4]

References[edit | edit source]

  1. 1.0 1.1 1.2 Fujita A, Murata K, Takamori M. Novel method for sputum induction using the Lung Flute in patients with suspected pulmonary tuberculosis. Respirology. 2009 Aug;14(6):899-902.
  2. Medical Acoustics. Product overview. Lung Flute® operation. [Accessed 29 March 2020]. Available from URL: http:// LungFluteOperation.
  3. The Lung Flute - Instructional Video. 929Media. Available from: [Accessed 28 April 2020]
  4. 4.0 4.1 4.2 Sethi S, Maloney J, Grove L, Anderson P. Comparison of the lung flute with the acapella in the treatment of COPD with chronic bronchitis. unpublished data. 2018.
  5. Parikh NU, Mammen MJ, Cumella JC, Rockoff JB, Schwartz SA. Impact of Lung Flute Therapy on Asthma: A Pilot Study. J Allergy Clin Immunol. 2017 Feb 1;139(2):AB97.
  6. Ashwini D, Medha D. Effectiveness of lung flute-an OPEP device for bronchial hygiene in a patient with cystic bronchiectasis: a case report. Int J Health Sci Res. 2015;5(5):570-5.
  7. Doumit M, Jaffé A. Use of the lung flute for sputum induction in children with cystic fibrosis: a pilot study. Pediatr Pulmonol. 2015; 50:340–343.
  8. Elhawary A, Ismail NA, Esawy MM, Shabana MA. Efficacy and safety of a new acoustic device, the lung flute, for sputum induction and lung physiotherapy. Egypt J Chest Dis Tuberc 2020;69:259-65