Vibrating Mesh Nebulizer Compared With Metered-Dose Inhaler in Mechanically Ventilated Subjects

BACKGROUND: The impact of various aerosol delivery devices on patient outcomes during mechanical ventilation is unknown. If one method of delivery results in a higher ventilator-associated pneumonia (VAP) rate than another, multiple patient outcomes may be affected. This study aimed to determine whether there was a difference in VAP occurrence and patient outcomes (days receiving ventilation and in-hospital mortality) between the vibrating mesh nebulizer (AeroNeb Solo) and the metered-dose inhaler (MDI). METHODS: This retrospective study reviewed medical records for all mechanically ventilated, adult patients with an order for aerosol treatment from August 2011 to August 2013. The hospital converted from MDI to vibrating mesh nebulizers in August 2012, and data were gathered 1 y before/after conversion. Excluded were patients with a tracheostomy, patients whO were mechanically ventilated for <24 h, patients who received a combination of nebulizer and MDI treatments, or patients who were re-intubated. RESULTS: Two hundred twenty-eight subjects were included. Forty-eight (21%) received treatment with an MDI, and 180 (79%) were treated with the vibrating mesh nebulizer. Descriptive data did not significantly differ for age or APACHE II (Acute Physiology and Chronic Health Evaluation H) scores between the groups but did for sex (P =.03). Difference in median days receiving ventilation for the MDI (5 d, interquartile range 3.0-8.5 d) and the vibrating mesh nebulizer (6 d, interquartile range 4.0-10.0 d) was not statistically significant. No correlation was found between the use of either device and the primary outcomes of VAP and in-hospital mortality. In multivariable logistic regression analysis, the number of days receiving ventilation increased the odds of VAP (odds ratio [OR] 13, 95% CI 1.14-1.49, P <.001) and mortality (OR 1.12, 95% CI 1.04-1.21, P =.002). Higher APACHE II scores increased the odds of mortality (OR 1.05, 95% CI 1.001-1.092, P =.044). CONCLUSION: We found no association between an MDI or vibrating mesh nebulizer and our primary outcomes, days receiving ventilation, in-hospital mortality, or VAP, in mechanically ventilated subjects.