Evaluation of a system for the delivery of inhaled beclomethasone dipropionate to intubated neonates

Abstract

Since systemic dexamethasone therapy for bronchopulmonary dysplasia is associated with numerous side effects, a simple system to deliver aerosolized beclomethasone dipropionate (BDP) directly to the lungs of intubated neonates was developed and evaluated in vitro. The system consists of a self-inflating bag, metered dose inhaler (MDI) adapter, Tygon spacer and endotracheal tube (ETT). A dose is delivered by discharging the MDI into the system and giving 3 'breaths' with the bag. Different sizes of ETT do not affect the drug output (1.17 +/- 0.29 vs. 1.32 +/- 0.34 micrograms of BDP per dose using a 3.0-mm or 3.5-mm ETT, respectively; means +/- SD). However, a shorter system spacer substantially reduces the drug output. The majority (54.0%) of the particles exiting the ETT and available to the patient are in the respirable range (0.5-5.5 microns). Based on adult doses and delivery of BDP and the relative sizes of the adult and neonatal lung, it is estimated that a neonate will require 1-6 doses/day. Replacing dexamethasone in the treatment of bronchopulmonary dysplasia with aerosol topical steroids delivered by this system may improve both the safety and efficacy.