A Comparison of Amount and Speed of Deposition Between the PARI LC STAR® Jet Nebulizer and an Investigational eFlow® Nebulizer

Background: The potency and physical properties of many of the drugs used in the treatment of cystic fibrosis necessitates the use of nebulization, a relatively time-consuming pulmonary delivery method. Newer, faster, and more efficient delivery systems are being proposed. The purposes of this study was to compare the length of time it took to deliver the equivalent of normal saline nebulized for 10 min in a PARI LC STAR (R) nebulizer to that of an investigational PARI eFlow (R). Methods: Six normal adults inhaled a 4-mL (36-mg) charge volume of saline from the LC STAR (R) or a 2.5-mL (22.5-mg) charge volume from the investigational eFlow (R). The saline was mixed with (99)m Tc-DTPA to allow two-dimensional imaging. The inhalation was preceded by a xenon equilibration scan to allow more accurate separation of deposition into central and peripheral lung regions. Results: The investigational eFlow (R) delivered 8.6 +/- 1.0 mg, approximately 90% of the lung dose compared to the LC STAR (R), 9.6 +/- 1.0 mg, but did in less than half the time (p < 0.02 for both). There were no differences in central versus peripheral distribution for either device. Conclusions: In conclusion the investigational eFlow (R) was both faster and more efficient than the LC STAR (R).