Dolby Vivisol - Expiratory Flow Accelerator - How Does It Work? 

The Expiratory Flow Accelerator (EFA) uses a patented technology capable to accelerate the expiratory flow.
The acceleration of the air during expiration facilitates the movement of the mucus and possible solid or liquid residues - enhancing the natural physiology of the body.
Secretions reach the upper respiratory tract safely allowing the patient to expel or swallow them.
No negative pressure is produced in the lungs, avoiding the risk of airway collapse.