Abstract Rationale The efficacy of valved holding chambers (VHC) with masks critically depends on achieving an effective mask-to-face seal, which is influenced by mask design and the applied force. Insufficient pressure can increase leakage and reduce inhaled doses, potentially compromising therapeutic effectiveness. While regulatory standards specify an application pressure of 16N for in-vitro testing, real-world use typically involves ∼4N, which is more comfortable and better tolerated by children. This study evaluated leakage and aerosol performance under clinically realistic pressures alongside a caregiver questionnaire assessing mask comfort, usability, and acceptance of the new design. Methods Two pediatric face models from the Liam (Louis Infant Anatomical Model) family, Liam Baby (9 months) and Liam Infant (2-3 years) were used to evaluate three commercially available VHC face masks with their respective chambers. Models replicate pediatric facial geometry and soft-tissue compliance based on 3D scans of real children. Mask-face leakage and aerosol delivery of budesonide were measured at 4N contact force using a validated test setup. An electronic questionnaire was administered to caregivers of pediatric patients prescribed a VHC to assess mask usability, seal perception, comfort, and acceptance. Results Among baby-sized masks, Vortex’s minimal leakage (2.2%±0.17, mean±SD) from better seal integrity corresponded to the highest respirable dose of budesonide (34.36 ± 5.4), while OptiChamber Diamond and AeroChamber masks exhibited higher leakage (17.4%±4.1,35.9%±1.8) and lower respirable doses respectively (11.30 ± 1.5, 0.01 ± 0.01). For child-sized masks, Vortex showed the lowest leakage (1.3%±0.5) and consistent drug delivery (31.66 ± 3.5). Despite moderate leakage, OptiChamber and AeroChamber (8.4%±4.8,10.6%±1.7) delivered adequate doses of budesonide (27.45 ± 5.2, 22.97 ± 4.7). Preliminary analysis of the caregiver questionnaire (n = 30) indicates high satisfaction with the mask. Most reported it was comfortable, sealed effectively with minimal pressure, with 96% reporting overall acceptance by their child. Conclusions Facemask leakage can substantially reduce the effectiveness of drug delivery in pediatric patients using VHCs. Testing under clinically realistic 4N application forces showed that mask performance can differ markedly. The Vortex pediatric masks achieved effective sealing and drug delivery under representative use conditions. Preliminary caregiver feedback indicates 96% acceptance with favorable usability, underscoring the importance of evaluating both technical performance and real-world comfort in pediatric aerosol delivery systems. This abstract is funded by: PARI GmbH
Cambridge et al. (Fri,) studied this question.