Delivery of high solubility polyols by vibrating mesh nebulizer to enhance mucociliary clearance

Background: Inhaled dry powder mannitol has established in vivo therapeutic efficacy for enhancing mucociliary function. However, a single dose necessitates multiple inhalations of a sizeable powder mass. Nebulization of mannitol by vibrating mesh devices has recently been shown in vitro to impart similar dosing in a comparable or lesser treatment time. Nevertheless, the limited solubility of mannitol restricted fluid concentrations to 150 mg/mL. The present study examines the feasibility of higher solubility polyols that presumably possess similar therapeutic properties to mannitol but deliverable at higher concentrations to shorten treatment time. A secondary aim is to compare delivery by two commercially available mesh nebulizers—the Aeroneb® Go and PARI eFlow Rapid.

Methods: A series of formulations containing three polyols (mannitol, sorbitol, and xylitol) of increasing concentration in 1% w/v sodium chloride were nebulized. Aerosol characteristics and treatment times were determined primarily by laser diffraction.

Results: Results indicate viscosity is the primary determinant of vibrating mesh nebulizer performance. For both nebulizers, xylitol 334 mg/mL exhibits the greatest osmolar output—double that of 150 mg/mL mannitol.

Conclusions: A nebulized xylitol solution has potential clinical application for promoting rapid mucociliary clearance. Both vibrating mesh nebulizers facilitate quick treatment times. Future in vivo studies would compare the efficacy of nebulized xylitol to commercial hyperosmolar agents and establish any potential polyol-associated antibacterial activity.