Albuterol Delivery During Invasive Mechanical Ventilation via In-Line Intrapulmonary Percussive Ventilation in a Pediatric Lung Model

BACKGROUND: Patients receiving mechanical ventilation often require airway clearance and inhaled therapies. Intrapulmonary percussive ventilation (IPV) combines a high-frequency percussive ventilator with a jet nebulizer. Data on aerosol delivery efficiency of the device are scarce. We evaluated albuterol delivery efficiency while using an IPV in-line adapter under different conditions.

METHODS: A pediatric lung model of invasive mechanical ventilation was used. The following independent variables were evaluated: lung condition (normal vs ARDS), ventilator mode (adaptive pressure ventilation vs pressure control), percent opening of adapter (0% vs 25% vs 50%), IPV driving pressure (25 psi vs 40 psi), IPV percussion setting (easy vs hard), and endotracheal tube (ETT) size (3.5 mm vs 5.5 mm). Albuterol delivery efficiency (mass captured in the filter expressed as percentage of loading dose) was selected as the dependent variable. Albuterol was captured on a filter at the tip of the ETT and quantified via spectrophotometry (276 nm).

RESULTS: Albuterol delivery efficiency ranged from 0–2.89%. Median (interquartile range) and 95% CI around the median were 0.54% (0.37–1.00) and 0.50–0.63%, respectively. The coefficient of determination (R²) for the model including all variables was 0.363. The 2 main contributors were percent of adapter opening (R² 0.30) and IPV setting (R² 0.039).

CONCLUSIONS: Albuterol delivery during invasive mechanical ventilation via in-line IPV in a pediatric lung model was inefficient. Alternative methods of delivering bronchodilators and other inhaled medications should be considered when IPV is used.