Aerosol delivery using pediatric valved holding chamber face masks under real-life application pressure

<bold>Introduction:</bold> Insufficient application pressure of pediatric valved holding chamber (VHC) face masks increases mask-to-face leakage. Regulatory standards recommend an application pressure of 16 Newtons (N) for in vitro testing. However, real-world data show that caregivers typically apply only around 4N, which is better tolerated by children. This study investigated how face mask leakage at low contact forces, such as 4N, affects the respirable dose of Budesonide. <bold>Methods:</bold> Two models from the Louis Infant Anatomical Face Model (LIAM) family - LIAM Baby (9 months) and LIAM Infant (2-3 years) - were used to evaluate five commercially available VHC face masks along with their respective chambers for babies and children. These models, based on 3D scans of children's faces, accurately replicate the facial geometry and varying tissue firmness of pediatric patients. Leakage and aerosol performance were measured using a validated test setup at 4N contact force. <bold>Results:</bold> Among baby masks, VORTEX demonstrates superior performance with minimal leakage and highest respirable dose. L‘Espace provides adequate sealing but does not deliver a high respirable dose. OptiChamber, RC Chamber and Aerochamber show higher leakage and lower respirable doses. Among child masks, VORTEX and RC Chamber exhibit the lowest leakage rates, ensuring high drug delivery. In contrast, L'Espace shows the highest leakage, correlating with the lowest respirable dose. OptiChamber and AeroChamber exhibit higher leakage rates but still deliver adequate respirable doses. <bold>Conclusion:</bold> Among all tested VHC masks, VORTEX had the lowest leakage and highest respirable dose, making it the most effective option for babies and children.