RT Journal Article SR Electronic T1 IN-VITRO EVALUATION OF POSITIVE EXPIRATORY PRESSURE DEVICES ATTACHED TO NEBULIZERS. JF Respiratory Care FD American Association for Respiratory Care SP respcare.02698 DO 10.4187/respcare.02698 A1 Ariel Berlinski YR 2013 UL http://rc.rcjournal.com/content/early/2013/08/06/respcare.02698.abstract AB Introduction Patients with Cystic fibrosis perform airway clearance techniques and receive nebulized medications on regular basis. Some positive expiratory pressure (PEP) devices allow concomitant administration of nebulized aerosols. We hypothesize that this practice may alter the aerosol characteristics and patient dose. We compared the aerosol characteristics and patient dose of nebulized albuterol generated by 2 different types of nebulizers alone and when connected to different PEP/vibratory PEP devices. Materials and Methods Three units of a continuously operated nebulizer (CON ) and 3 units of a breath enhanced nebulizer (BEN) were tested alone and connected to PEP devices (acapella® choice, acapella® duet, and EzPAP® for CON and PARI PEP™ at 2 different settings and PARI PEP™ S system for BEN). Aerosol characteristics were evaluated by cooled cascade impaction technique. Nebulizers were loaded with 2.5mg/3mL albuterol solution and operated for 4 minutes (6L/min, central air). Patient dose was evaluated with simulated breathing technique using child, small adult, and large adult breathing patterns. Albuterol was assayed via spectrophotometer (276 nm). Results Connecting the BEN to PEP devices did not change either aerosol characteristics or patient dose. Connecting the CON to PEP devices resulted in significant reduction of mass median aerodynamic diameter from 4.13 μ to 3.72 μ, 1.24 μ and 1.22 μ when connected to EzPAP® (p = 0.021), acapella® choice (p < 0.0001) and acapella® duet (p < 0.0001) respectively. Total amount of albuterol captured by the impactor decreased when connected to either acapella® choice (65%) or acapella® duet (69%) with 17%-25% retained in the PEP devices. Patient dose decreased by 76% to 84% when connected to acapella® choice and acapella® duet respectively. Conclusions Concomitant use of nebulizers and PEP/vibratory PEP devices that obstruct the aerosol pathway produce a significantly smaller particle size aerosol and a significant decrease of patient dose.