Incoming Flow Turbulence Reduction Increases the Efficiency of Aerosolized Medication Delivery to 3D Oral Mucosal Tissue Models.

Abstract

Background: Inhalable medication devices on the market deliver aerosolized drugs in a turbulent flow, which creates significant obstacles for reaching the lower lungs. The complexity of the interaction of external turbulent flow from an inhalation device with complex anatomy of the upper airways, including the oropharyngeal cavity, makes the fidelity of aerosolized medication delivery to the lungs extremely low. Unpredictable outcomes, waste, and side effects result from unintended upper airway drug deposition. Methods: Here we compared the efficiency of aerosolized medication (fluticasone) delivery via a novel Flow Modification Device (ModiFlow) to that of a Standard Spacer (SS) device. The ability of ModiFlow to minimize the turbulence in the flow was assessed preliminarily by measuring the length of the Laminar Outflow using video recording. Oral mucosal 3D tissue culture (SkinAxis) was used as a target for delivery, and was placed either “well within” the range of the length of the oro-pharyngeal cavity (5cm) or “well outside” of it (20cm) from exit points of each device. The efficiency of fluticasone delivery to the surface of tissue cultures was quantified by mass spectrometry. Results: The results of the study demonstrated a statistically significant advantage of ModiFlow over a Standard Spacer in delivering aerosolized fluticasone to target tissue at both distances. The difference in the efficiency of delivery between the two spacers was more pronounced at a longer distance.Conclusions: Lamination of the outflow using internal septi helps improve the delivery of aerosolized medication to target tissue despite an increased inner surface area of the spacer device, which also indicates lesser deposition of the medication on the walls of the test tube. This suggests that the use of ModiFlow will potentially result in the more efficient delivery of aerosolized medications to the lungs with lesser deposition in the oral cavity and fewer side effects.