We at Hyfe, Inc., are a company devoted to working on tools to better understand the importance of cough. It is Hyfe’s intention in the future to seek regulatory approval for medical products that analyze cough in order that they may be used to diagnose, monitor, and facilitate better treatment of respiratory illnesses.
Everyone has experienced a cough at some point in their life. While it can be annoying, coughing is the body’s way of clearing obstructions such as mucus and foreign bodies from the airways. But what do you do if coughing is not enough to clear your airways? What if the mucus builds up a lot? How to get mucus out of lungs? Having too much mucus in your lungs not only makes you susceptible to infection but it can also worsen any underlying diseases you may have, like chronic obstructive pulmonary disease (COPD) or asthma. This is where airway clearance techniques (ACTs) come in.
Airway clearance techniques describe different strategies we can use to clear excess secretions in our airways1. ACTs aim to eliminate airway obstructions, leading to reduced infection, improved gas exchange, decreased inflammation, and, ultimately, healthier lungs.
While there are numerous techniques out there, we have curated a list of the most commonly used airway clearance techniques.
Coughing and huffing often effectively clear mucus buildup. While coughing is something that comes naturally to us, huffing may require a little explanation. It is similar to how you would breathe on your glasses to clean them2.
This technique begins with inhaling deeply through the nose. While holding in your abdomen, forcefully breath the air out in three equal breaths and make a “huffing” sound from your throat. Repeat this technique 2-3 times for adequate clearance.
This strategy uses an inflatable vest attached to a compressor that rapidly inflates and deflates the vest at a frequency of 5–25Hz. These vibrations travel through the chest wall and throughout the lungs, decreasing the viscosity (thickness) of secretions. HFCWO also improves the activity of the cilia, which are fine filaments lining the lungs that function to sweep debris and foreign bodies upward and out of the lungs3.
A temporary positive expiratory pressure (TPEP) device uses a mild pulsing airflow to reduce pressure in the airways by improving the elasticity of the lung walls, which reduces any excessive lung distension and relieves trapped air, as well as loosening mucus in the lungs4. This has been found to greatly benefit patients with emphysema (damaged air sacs in the lungs) or those on oxygen therapy.
This technique uses certain positions and gravity to drain secretions from the lungs. The type of postural drainage varies depending on where most of the mucus is located. You may have to sit at an angle, lay flat on your back or on your chest with a pillow under your knees, or lay on your side. Spending time in the correct position will allow gravity to move secretions to other locations in the lungs so they can be coughed out. Consulting a healthcare provider will provide better insight into the best positions for effective drainage of your lung secretions.
These techniques can’t be performed by the individual – it need to be performed by a respiratory therapist or a caregiver. In manual CPT, a trained individual rhythmically claps on the chest to loosen mucus and dislodge debris that may be clogging the airways5. There are two type of technique: percussion and vibration. Percussion or chest clapping involves the application of rapid. Light, rhythmic strokes with cupped hands to the chest area where most of the secretions are pooled, during both inhalation and exhalation6.
The strength of percussion depends on your comfort, so do not hesitate to inform your respiratory therapist or caregiver if you feel discomfort. Vibration involves the application of small, circular movements during exhalation, accompanied by sufficient compression of the chest wall increase the rate of exhalation7.
The active cycle of breathing technique (ACBT) uses different breathing patterns to clear mucus through three phases8. The first phase involves breathing control, wherein you slowly inhale through the nose and exhale through your mouth. This not only relaxes the airways, but also keeps them open longer. Do this for six breaths.
The second step is to perform chest expansion exercises. Inhale deeply, for around three seconds, then exhale gently while clapping or rubbing your chest to loosen secretions. Follow one of these with another cycle of breathing control for six breaths. The last step is huffing or coughing. After inhaling deeply, forcefully exhale three times while making a “huffing” sound to force the secretions out of the lungs. Repeat this huffing until all mucus is coughed or huffed out from the lungs. Each time, make your huff a different length from the previous set, as this will enable the air to access different parts of your lungs. ACBT requires some practice, but is an effective way to clear the airways.
This airway clearance technique does not require a specific device or equipment and is similar but more complex to ACBT. Autogenic drainage requires you to breathe in certain patterns9. These breathing patterns should not only reduce the adhesion of mucus to the airways, but also transport them away from the lungs. However, this technique is easier said than done, as it requires a certain level of skill to perform and may be difficult for some patients to follow. It is too complex to explain here, and should be only taught by trained medical professionals, so discuss with your PCP if you think autogenic drainage would be helpful for you.
This airway clearance strategy involves exhaling against air resistance to produce positive pressure in the airways. This happens through making it more difficult to exhale all the air breathed in, leading to a buildup of pressure behind any mucus secretions, leading to a pressure gradient that would then move the secretions toward the lungss exit10.
A variation of this is oscillatory positive expiratory pressure (OPEP)11. OPEP additionally applies oscillating, vibratory frequencies to PEP. The combination of pressure and vibration help loosen and clear secretions.
Overall, the use of airway clearance techniques depends on your condition, comfort, and preference. Research does not indicate that one technique is superior to another12, but it does say that you are more likely to adhere to treatment if the techniques are self-administered13.
Therefore, it is important to collaborate with your healthcare provider in order to choose the most appropriate airway clearance technique for you. This will not only improve your comfort in the long run but also the health of your lungs.
Mikaela is a dentistry clinician at the University of the Philippines.