Aerosol Guide - AARC.org

aerosol is created by a passive mesh, and aerosol is injected into the breath at the beginning
of inhalation (Figure 12). The dosage of the drug is controlled through specific metering
chambers. The metering chambers can deliver a pre-set volume ranging from 0.25 to 1.7
mL with a residual volume of about 0.1 mL. The I-neb ® model incorporates an AAD algorithm
that pulses medication delivery into 50–80% of each inspiration, based on a rolling
average of the last three breaths. Throughout the treatment, the I-neb ® provides continuous
feedback to the patient through a liquid crystal display; and upon successful delivery of the
treatment, the patient receives audible and tactile feedback.
Figure 12. Adaptive aerosol delivery as provided by the Philips Respironics I-neb ® .
As illustrated, aerosol is injected into the breath at the beginning of inhalation.
(With permission of Respironics)
Nebulizers for Specific Applications
Nebulizer for Ribavirin Administration
The small-particle aerosol generator (SPAG) is a large-volume nebulizer designed solely to
deliver aerosolized ribavirin (Virazole ® , Valeant Pharmaceuticals, Aliso Viejo, CA) for prolonged
periods of nebulization. It consists of a nebulizer and a drying chamber that reduces
the MMAD to about 1.3 µm. Because of teratogenic characteristics of ribavirin, a scavenging
system is strongly recommended for use during its administration.
Nebulizer for Aerosolized Pentamidine Administration
When administering aerosolized pentamidine, an SVN fitted with inspiratory and expiratory
one-way valves and with expiratory filter is used. These valves prevent exposure of secondhand
pentamidine aerosol and contamination of the ambient environment with exhaled
aerosol.
Continuous Aerosol Therapy
Continuous aerosol drug administration is a safe treatment modality and is used to treat
patients suffering acute asthma attack. Researchers reported that it may be as effective as
intermittent aerosol therapy or may, in fact, be superior to intermittent nebulization in
patients with severe pulmonary dysfunction. 39 Figure 13 illustrates a basic setup for continuous
aerosol therapy that includes an infusion pump, a one-way valved oxygen mask, and a
reservoir bag. Commercial nebulizers used in continuous nebulization commonly have luer
lock ports designed for use with infusion pumps. The nebulization is most commonly
administered using standard aerosol masks.
18 American Association for Respiratory Care A Guide to Aerosol Delivery Devices for Respiratory Therapists, 3rd Edition © 2013