CH. 3 Administration of Aerosolized Agents Flashcards
What is aerosol
is a suspension of solid or liquid particles within a gas
Aerosol Therapy
-humidification of dry-inspired gases
-improved mobilization and clearance of respiratory secretions
-delivery of aerosolized drugs to the respiratory tract
Disadvantages of Aerosol
-numerous variables affect the dose
-dose estimation and dose reproducibility are inconsistent
-difficulty in coordination of hand action and breathing
-Many different device types
Aerosol Stability
the tendency of an aerosol to remain in susoension
Aerosol Penetration
how far into the lungs the aerosol particles travel
Aerosol Deposition
the aerosol particles falling out of suspension and remaining in the lung
Aerosol Gravitational sedimentation
last five or six airway generation
Aerosol Inertial Impaction
the impacting of aerosol particles in airway walls because of inertial energy
Breathing Pattern
Only about 10-50% of drug gets into the lung
Fast Breathing
cause turbulence that favors inertial impaction and deposition
Slow Breathing
produces more laminar flow and results in deeper penetration of the aerosol particles
Small Volume Nebulizer (SVN)
-Administers liquid medication as aerosols
-powered by compressed gas or electrical
-lasts several minutes or can be continuous
Jet Nebulizers with Reservoir tube
-traditional, most common, least expensive
-Aerosol is dispensed during inhalation, breath hold, and exhalation
-Much aerosol is lost
-10-20% of drug is inhaled
Jet Nebulizers with Collection bag
-Produces aerosol by continuously filling a collection bag
-No aerosol is lost due to the one-way valve
Enhanced Jet Nebulizers
–More aerosol release during inspiration with decreased output during exhalation or breath-hold
– 2 one-way valves used to prevent the loss of aerosol to the environment
Actuated Jet Nebulizer
-Release aerosol only during inspiration
-Increase aerosol drug delivery to the patient
-Can be manual breath-actuated
-Mechanical breath actuated
Mesh Nebulizers
-Delivers up to 60% of dose to lungs
-low dead volume
-no diluent
-Short treatment time
Ultrasonic Nebulizer
-Capable of high output
-Not used much
Factors that Affect SVN
-Dead volume
-Filling volume and treatment time
-Effect of flow rate
-Type of power gas
-Device interface
Type of solution
Metered Dose Inhaler (MDI)
-Most common
-Small and portable
-Propellant inside a canister filled with medication
—CFCs- bad for the environment, no longer on the market
—HFA- safer for the ozone layer
-Used with a reservoir
-Sprayed at a high flow rate
Breath Actuated MDI
Respimat Soft Mist Inhaler- propellant-free, does not need to be shaken
Factors affecting MDI
Timing of actuation intervals
Loss of dose
shaking canister
open mouth versus closed mouth used
loss of prime
storage temperature
Dry Powder Inhaler (DPI)
-Deliver drug in powder form to the lungs
-No propellant, breath-actuated
-Small and portable
-Patient need high flow rate
Choosing an Appropriate device
Patient or clinical preference
Convenience of device
Practicality of device
durability of device
cost and reimursement
drug availability
Appropriate to use MDI
-with holding chamber
-patient must be able to follow instructions
Appropriate to use SVN
-a patient cannot follow directions
-respiratory pattern unstable
-unable to take a slow, deep breath with an inspiratory hold
