As we continue our deep dive into airway clearance our second breathing technique for airway clearance is autogenic drainage (AD). This technique was developed in 1967 by Jean Chevaillier and was first limited to only asthma before later being applied or rather approved for use in other airway diseases associated with overproduction of mucus in the bronchial tree. Autogenic drainage uses controlled breathing to manipulate airflow ventilation throughout the airways to collect and move mucus within the airways. This recruitment of mucus using airflow requires a huge amount of patient cooperation, coordination, self evaluation or self awareness of mucus, and understanding of the technique for AD to be effective for the patient. This is why this technique is not recommended for patients under the age of eight years of age. It also reinforces the need for proper training by a licensed respiratory therapist and should not be undertaken by simply reading about the technique on the internet or being coached by a non-professional. Autogenic drainage in it’s basic form means self drainage. It’s aims are to recruit the movement of mucus from the lower airways to the upper airways using different breathing frequencies without causing airway collapse that can happen during forced expiratory pressures of other airway clearance techniques.

As we continue our deep dive into airway clearance our second, most basic, and next easiest airway clearance technique (ACT) is breathing. Breathing is another important part to all other airway clearance techniques. Breathing helps to get air in behind sections to help on the exhale to shear mucus with typical viscosity away from typical airway walls. The thicker the viscosity of the mucus the harder it is to shear the mucus away from typical airway walls with breathing and coughing alone. The same can be said for mucus that has less viscosity than typical mucus. Or rather if the mucus is too thin, thin mucus can prevent air from staying behind the mucus to allow for the exhale or expiratory forces of air to mobilize and move the mucus. In fact; if mucus is too thin, it can slip further into the alveoli area of the lungs where it gets stuck without more aggressive airway clearance measures. The condition of a patient’s airway walls also has some to do with cough and breathing to move mucus within the airways. But breathing for airway clearance is not your normal everyday breathing, it is breathing focused and directed with a purpose. It requires thought and concentration. This type of breathing for airway clearance is termed active cycle breathing or active cycle of breath in countries outside of the United States.