Aerosol delivery aspects within a high-flow therapy system in COPD patients.

There is a lack of information about the influence of patient interfaces such as facemasks or mouthpieces on the effective dose of aerosolised drugs while using high-flow therapy in a clinical setting. These interfaces can improve pulmonary drug delivery over nasal cannulas but patient preference and comfort should also be considered. The present work was to determine the effect of three different interfaces (nasal cannula, valved face mask, and mouthpiece) when combined with titrated oxygen flow on aerosol delivery in patients with COPD hospitalised due to acute exacerbation. The variations between these interfaces were addressed in terms of change in lung function measurements pre-and post-inhalation, the delivered salbutamol dose, and patient tolerance to each interface. A high-flow nasal cannula was the most comfortable interface used. However, its pulmonary drug delivery was significantly lower than both the valved face mask and mouthpiece (p<0.05). Although drug delivery was different with the three tested interfaces, the lung function improvements were similar.