Characterizing regional drug delivery within the nasal airways.

Introduction: The nose has been receiving increased attention as a route for drug delivery. As the site of deposition constitutes the first point of contact of the body with the drug, characterization of the regional deposition of intranasally delivered droplets or particles is paramount to formulation and device design of new products.

Areas Covered: This review article summarizes the recent literature on intranasal regional drug deposition evaluated in vivo, in vitro and in silico, with the aim of correlating parameters measured in vitro with formulation and device performance.

High-Flow and Low-Flow Oxygen Delivery by Nasal Cannula Evaluated in Infant and Adult Airway Replicas.

Background: The nasal cannula is widely regarded as a safe and effective means of administering low- and high-flow oxygen to patients irrespective of their age. However, variability in delivered oxygen concentration (F F ) via nasal cannula has the potential to pose health risks. The present study aimed to evaluate predictive equations for F over a large parameter space, including variation in breathing, oxygen flow, and upper-airway geometry representative of both young children and adults.

Size-specific filtration efficiency and pressure drop of school-aged children's woven and nonwoven masks at varying face velocities.

Background: Differences in physiology and breathing patterns between children and adults lead to disparate responses to aerosols of varying sizes. No standardized method exists for measuring the filtration efficiency (FE) of children's masks to reflect such differences.

Methods: Using an adult N95 mask as a control and two different face velocities (v) (9.