Comparison of Aerosol Delivery by Face Mask and Tracheostomy Collar.
BACKGROUND
The purpose of this study was to compare the performance of a tracheostomy collar, Wright mask, and aerosol mask attached to a jet nebulizer in facilitating aerosolized medication delivery to the lungs. We also compared albuterol delivery with open versus closed fenestration and determined the effect of inspiratory-expiratory ratio (I:E) on aerosol delivery.


METHODS
Albuterol (2.5 mg/3 mL) was administered to an in vitro model consisting of an adult teaching mannequin extrathoracic and upper airway with stoma intubated with an 8-mm fenestrated tracheostomy tube. The cuff was deflated. A collecting filter at the level of the bronchi was connected to a breathing simulator at a tidal volume of 400 mL, breathing frequency of 20 breaths/min, and I:E of 2:1 and 1:2. A jet nebulizer was operated with O2 at 8 L/min. Each interface was tested in triplicate. The flow was discontinued at the end of nebulization. For each test, the nebulizer was attached to a tracheostomy collar with the fenestration open or closed, a Wright mask, or an aerosol mask. Drug was analyzed by spectrophotometry (276 nm). A paired t test and analysis of variance were performed (P < .05).


RESULTS
The mean ± SD percent albuterol dose delivered distal to the bronchi was greater with the tracheostomy collar with a closed fenestration (9.4 ± 1.5%) compared with an open fenestration (7.0 ± 0.8%). The doses delivered with the Wright mask (4.1 ± 0.6%) and aerosol mask (3.5 ± 0.04%) were both less than with the tracheostomy collar under either condition (P < .05). Increasing the I:E from 1:2 to 2:1 increased aerosol delivery by 2.5-4%, with significance for the tracheostomy collar with an open fenestration (11.6 ± 1.4%), Wright mask (7.2 ± 0.6%), and aerosol mask (6.1 ± 0.5%).


CONCLUSIONS
In an adult tracheostomy model, the tracheostomy collar delivered more aerosol to the bronchi than the Wright or aerosol mask. An I:E of 2:1 caused greater aerosol deposition compared with an I:E of 1:2. During aerosol administration via a tracheostomy collar, closing the fenestration improved aerosol delivery.
Division of Respiratory Care, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia.
Alaa A
AA
Bugis
Division of Respiratory Therapy, Georgia State University, Atlanta, Georgia.
Meryl M
MM
Sheard
Division of Respiratory Therapy, Georgia State University, Atlanta, Georgia. James B Fink, LLC, San Mateo, California.
James B
JB
Fink
Division of Respiratory Therapy, Georgia State University, Atlanta, Georgia.
Robert J
RJ
Harwood
Division of Respiratory Therapy, Georgia State University, Atlanta, Georgia.
Arzu
A
Ari
D000280:Administration, Inhalation; D000336:Aerosols; D000420:Albuterol / Q000008:administration & dosage*; D001993:Bronchodilator Agents / Q000008:administration & dosage*; D016503:Drug Delivery Systems / Q000295:instrumentation*; D004867:Equipment Design; D006801:Humans; D008348:Manikins; D008397:Masks; D009330:Nebulizers and Vaporizers; D012119:Respiration; D013990:Tidal Volume; D014139:Tracheostomy / Q000295:instrumentation* / Q000379:methods
D000336:Aerosols; D001993:Bronchodilator Agents; D000420:Albuterol
I:E ratio; aerosols; fenestration; mask; nebulizers; respiratory drug administration; tracheostomy