The Science Journal of the American Association for Respiratory Care

2008 OPEN FORUM Abstracts

INFLUENCE OF NEBULIZER TYPE, POSITION AND BIAS FLOW ON AEROSOL DRUG DELIVERY IN A MODEL OF INFANT MECHANICAL VENTILATION.

Arzu Ari1, Orcin Telli2, James Fink3



Background: Background: Aerosol drug delivery during infant mechanical ventilation varies with aerosol generator type, position in the ventilator circuit and ventilator parameters. The purpose of this study was to determine the influence of position and bias flow with a jet (JN) and vibrating mesh (VM) nebulizer on albuterol sulfate delivery in a model of infant mechanical ventilation.

Methods: Albuterol sulfate (2.5 mg) was nebulized by JN (Misty Finity™, Cardinal) and VM (Aeroneb® Solo, Aerogen) nebulizers were operated at Position 1: JN and VM were placed 12 in from the "Y" adapter and Position 2: JN was placed prior to the heated humidifier using 6 inches large bore tubing. VM attached directly to the humidifier inlet. A ventilator (Galileo, Hamilton Medical) with a heated humidifier (F&P) and 10 mm ID heated wire ventilator circuit delivered infant settings (PIP 25 cmH2O, PEEP 5 cmH2O, RR 25/min, Tinsp 0.5 sec, Descending waveform) through a 3 mm ID ETT to an absolute filter attached to a test lung (Michigan Instruments) with bias flow of 2 and 5 lpm. Each experiment was repeated three times (n=3). Drug was eluted from the filter and analyzed by spectrophotometry (276 nm). A 3-way factorial ANOVA was used (p<0.05).

Results: The % inhaled dose (mean ± SD) presented in table. Placement prior to the humidifier increased drug delivery with both JN and VM. Increased bias flow reduced drug delivery. VM delivered more drug than JN (p<0.05).

Conclusion: During infant mechanical ventilation, VM was most efficient when placed at prior to the humidifier while aerosol delivery with JN was similar at both positions.