Efficiency of a New Mesh-Type Nebulizer (NE-SM1 NEPLUS) for Intrapulmonary Delivery of Ipratropium Bromide in Surgical Patients

This study was aimed to evaluate the efficiency of a new mesh-type nebulizer for the intrapulmonary delivery of ipratropium bromide in surgical patients under mechanical ventilation. A total of 20 patients were randomly allocated to receive 0.5 mg ipratropium bromide using either a control (Pariboy SX, Pari, Co., Starnberg, Germany, n = 10) or test (NE-SM1 NEPLUS, KTMED INC., Seoul, Korea, n = 10) nebulizer during general anaesthesia. Ipratropium bromide was nebulized continuously for 20 min. in each group. Plasma concentrations of ipratropium bromide were obtained from blood samples at preset intervals. Non-compartmental analysis of ipratropium bromide was performed to compare the efficiency of pulmonary drug delivery in both nebulizers. Population pharmacokinetic analysis of ipratropium bromide was performed. Additionally, the noise level during the nebulizer operation and the aerosol particle size for each device were measured. The dose-normalized AUC_last was 0.10 min/L for both nebulizers. The pharmacokinetics of nebulized ipratropium bromide can be described best by a one-compartment model with first-order absorption. The apparent volume of distribution and metabolic clearance were 1340 L and 6.78 L/min, respectively. Type of nebulizer was a significant covariate for absorption rate constant. The equivalent sound level and median aerosol particle diameter were 35.0 dB and 4.52 μm for the test nebulizer, and 60.2 dB and 3.85 μm for the control nebulizer, respectively. From the standpoint of the dose-normalized AUC_last, a new vibrating mesh-type nebulizer shows similar performance in the intrapulmonary delivery of ipratropium bromide to that of a jet-type nebulizer in surgical patients.