Modified forced expiration technique using expiratory resistance in adults with cystic fibrosis: A pilot study.

The design of this trial will be a randomised crossover trial. The study will consist of a morning and afternoon treatment (single day) consisting of 10 cycles of the participant’s usual airway clearance techniques (ACT). Each session will last approximately 30 minutes and the washout period will be at least 2 hours between sessions. Half (5) of the forced expiratory technique (FET) components will be performed with an expiratory resistance device (ERD), the other half will consist of the FET alone. The two FET methods will be alternated throughout each cycle in the session. There is no time period between airway clearance cycles, the patient will continue onto the next cycle as soon as they have caught their breath following the FET and cough. The expiratory resistance device will consist of a mask which provides positive expiratory pressure which aims to increase airway stability during a forced expiratory technique. The forced expiratory technique (otherwise termed a huff) is a form of airway clearance similar to a cough but requires less force, is less fatiguing and targets secretions from distal airways. Participants will be randomly allocated to perform the FET with the ERD or without the ERD and will alternate from the variable starting points. This will be repeated in the afternoon session, however the first cycle will start with the opposite FET method to the morning session. Ease of expectoration during the FET will be measured using a Visual Analogue Scale (VAS) following each cycle. The number of coughs will also be measured following each cycle. Sputum wet weight for each FET method and patient preference will be documented at the end of each session. Adherence to the intervention will be monitored by direct observation by study personnel.