FORCED OSCILLATION TECHNIQUE (FOT) – A NOVEL METHOD FOR THE DETECTION OF EARLY AIRWAY CHANGES

Abstract

According to the World Health Organization in 2019 chronic obstructive pulmonary disease (COPD) was the third leading cause of death worldwide, causing more than 3 million deaths whereas bronchial asthma affected more than 250 million people and caused 455 000 deaths. Both diseases are chronic obstructive conditions which need to be diagnosed early in order to prevent or slow down the complications. Consequently the world requires new effortless methods for diagnosis of airway obstructions, especially for small children and people who cannot perform the spirometry maneuver. The purpose of this report is to describe the objectives of the forced oscillation technique (FOT) and to establish its applications in the clinical practice. Studies and clinical cases regarding pulmonary function testing are summarized and analyzed. They are found in the following databases - PubMed, Google Scholar and Science Direct. Spirometry is the ‘gold standard’ for the diagnosis of airflow obstruction but it requires effort and can be difficult for patients to perform. Forced oscillation technique (FOT) on the other hand is a relatively new method that may hold the key to identifying smoking-related respiratory early alterations and childhood asthma. FOT requires tidal breathing while applying external, small amplitude oscillations in order to determine the response of the respiratory system. Therefore, it is easy for pre-school children to perform. The benefit of FOT should be taken into account for patients who cannot perform spirometry or other pulmonary function ttests. The minimal cooperation of the patient and the easy tidal breathing maneuvers make this method a great option for every pulmonologist. Compared to spirometry this technique may be more sensitive in the detection of disturbances of the peripheral airways and may be effective for the control of therapy at a long term. The Forced oscillation technique has been successfully applied in many pediatric respiratory disorders, such as asthma, cystic fibrosis, and chronic lung disease. Considering these qualities FOT may be used as an alternative of spirometry in heterogenous ventilatory disturbances of the small airways.