Aerosol Therapy Flashcards

Question

What is aerosol output?

Answer 1

The mass of fluid or drug contained in the aerosol product by a nebulizer. It is the mass of aerosol generated per unit of time.

Answer 2

The mass of drug leaving the mouthpiece of a nebulizer or inhaler as an aerosol.

Answer 3

It depends on their size, shape, and motion and on the physical characteristics of the airways. Key mechanisms causing aerosol deposition include inertial impaction, sedimentation, and Brownian diffusion.

Answer 4

The ability of aerosols to travel through the air, enter the airways, and deposit in the lung is largely based on particle size.

Answer 5

A suspension of liquid or solid particles in a gas.

Answer 6

Emitted Dose.

Answer 7

Deposition.

Answer 8

Mean mass aerodynamic diameter (MMAD).

Answer 9

When aerosol in motion collides with and are deposited onto a surface. The greater the mass and velocity of a moving droplet, the greater the inertia and tendency of that droplet to continue moving along its set path.

Answer 10

Pollens, Spores, Dust, Smoke, Fog, and Mist.

Answer 11

To deliver a therapeutic dose of the selected agent (drug) to the desired site of action.

Answer 12

Turbulent flow is a function of the ability of the patient to inhale the powder with a sufficiently high inspiratory flow rate.

Answer 13

It is the proportion of aerosolized drug of the proper particle size to reach the lower respiratory tract.

Answer 14

This is the primary mechanism for particles larger than 5 μm Occurs in the first 10 generations

Answer 15

Inertial impaction is a function of particle size (mass) and velocity There is a direct relationship with mass and velocity

Answer 16

The greater the mass and velocity of a particle the greater its inertia and tendency to move in a set path When a large particle is moving with a gas stream and the stream changes direction the particle tends to remain on the same path and collide with the airway surface A smaller particle on the other hand will tend to change direction along with the gas stream

Answer 17

Higher the flow of a gas stream the greater the tendency for particle to impact and be deposited in the airways Quicker particles can’t change direct easily. Turbulent flow, obstructed airways, and inspiratory flow greater than 30 L/min will increase inertial impaction Turbulent flow and convoluted passageways in the nose cause most particles larger than 10 μm to impact and become deposited.

Answer 18

Inertial impaction will filter out particles in order to help protect the lower airway from particulates such as dust and pollen Particles 6 to 10 μm tend to become deposited in the oropharynx and hypopharynx especially due to the turbulent air flow as it passes around the tongue and into the larynx

Answer 19

It depends on the substance being nebulized, the method used to generate the aerosol, and the environmental conditions surrounding the particle

Answer 20

Aerosols with particles of similar sizes.

Answer 21

The inspiratory flow rate, the flow pattern, respiratory Rate, inhaled volume, the I:E ratio, and breath-holding.

Answer 22

When aerosol particles settle out of suspension and are deposited due to the pull of gravity. Breath-holding after inhalation increases sedimentation and distribution in the lungs. The greater the mass of a particle, the faster it settles.

Answer 23

They are designed to collect aerosols of different size ranges on a series of stages or plates.

Answer 24

It occurs when aerosol particles settle out of suspension and are deposited owing to gravity. The greater mass of the particle, the faster it settles.

Answer 25

Cascade Impaction.

Answer 26

Inertial Impaction.

Answer 27

Variable or irregular passages and turbulent gas flow.

Answer 28

Size and time

Answer 29

There is increased settling for larger particles with slower velocities

Answer 30

particles 1 to 5 μm and will occurs mostly in the central airways

Answer 31

• As sedimentation  with time, an end- inspiratory breath hold maximizes sedimentation o e.g. a 10 sec breath-hold can  aerosol deposition by ~ 10% and increase the ratio of aerosol deposited in lung parenchyma to central airway by fourfold.

Answer 32

They are generated with devices that physically disperse matter into small particles and suspend them in gas.

Answer 33

The primary deposition mechanism for very SMALL particles and will deposit DEEP within the lungs.

Answer 34

It increases the residence time for the particles in the lung and enhances distribution across the lungs and sedimentation.

Answer 35

Brownian Diffusion is the primary mechanism for deposition of small particles (<3 μm) and will occur mainly in the region of the lung where bulk gas flow ceases and particles can reach the alveoli (particle inertia is low)

Answer 36

Small, low mass aerosol particles are easily bounced around by collisions with carrier gas molecules which will result in the deposition to surrounding surfaces

Answer 37

Particles 1 to 0.5 μm are stable and will remain in suspension and are cleared with the exhaled gas, whereas particles < 0.5 μm have greater retention rate in the lungs.

Answer 38

Aging: Process by which an aerosol suspension changes over time. Particles constantly growing, shrinking, coalescing or falling out of suspension

Answer 39

o Ambient conditions o Composition of aerosol o Initial size of particles o Time in suspension

Answer 40

hygroscopic tendancy or evaporation

Answer 41

inversly porportional to size Smaller particles grow faster than larger particles Small water based particles can also shrink when exposed to relatively dry gas Aerosols are generated in relatively dry ambient conditions and then taken into airway where both temperature and humidity increase

Answer 42

Optimal pattern of inhalation varies with type of aerosol generating device

Answer 43

The presence of airway obstruction is one of the greatest factors influencing aerosol deposition. Total pulmonary deposition is greater in smokers and patients with obstructive airway disease than in healthy persons

Answer 44

When inspiratory flow rates are constant, the deposition fraction of monodisperse aerosols increases with increased VT, length of inspiration, and particle size

Answer 45

Apporach to quantify aerosol deposition where a drug is tagged with a radioactive substance and then a scanner will be used to measure distribution

Answer 46

Adverse reaction to a drug

Answer 47

``` Infection Airway reactivity Systemic effects of bland aerosol Drug concentration Eye Irritation Secondhand Exposure ```

Answer 48

Cold air and high-density aerosols can cause reactive bronchospasm and increased airway resistance, especially in patients with pre-existing respiratory disease

Answer 49

acetylcysteine, antibiotics, steroids, ribavirin, and distilled water

Answer 50

Administration of bronchodilators before or with administration of these agents may reduce the risk or duration of increased airway resistance.

Answer 51

During nebulization, the evaporation, heating, baffling, and recycling of drug solutions undergoing jet or ultrasonic nebulization increase solute concentrations. This increase in concentration usually is time-dependent; the greatest effect occurs when nebulization of medications occurs over extended periods, as in continuous aerosol drug delivery.

Answer 52

Aerosol administration via a face mask may deposit drug in the eyes and cause eye irritation. In very rare cases, anticholinergic medications have been suspected to worsen pre-existing eye conditions, such as forms of glaucoma.

Answer 53

Repeated second-hand exposure to bronchodilators is associated with increased risk of occupational asthma. Unless filters are placed in the expiratory limb, 40% of aerosols produced during mechanical ventilation are exhausted to the air of the intensive care unit

Answer 54

``` Residual "Dead" Volume Ideal Filling Volume Tx Time Gas Source Flow Rate Gas Density ```

Answer 55

* Jet nebulizers do not aerosolize below minimum volume called ‘dead’ volume * Dead volume is amount of drug solution remaining in reservoir when device begins to ‘sputter’ and aerosolization ceases * ~ 0.5 to 1.0 ml but varies with different devices (always read the device manufacturers specifications)

Answer 56

At any given flow rate, Increase volume will increase time of effective nebulization A volume between 3- 5 ml (or as per manufacturers recommendation) of solution is recommended

Answer 57

incresed volume will decrease concentration of drug in residual volume and increase the drug dose to a patient increase volumes lenthen treatment time

Answer 58

Increased flow rate or gas pressure will decrease particle size and shift MMAD lower Increased flow rate or gas pressure will increase output and shorten treatment time

Answer 59

Affect aerosol production and depsoition decreased density (ex. heliox) will decrease aerosol impaction resulting in better deposition in the lungs When Heliox is used output is < than with air or O2 requiring increase in flow to produce comparable weight of aerosol per min Even though HEliox will incresae the amount of aerosol in lungs it will require high . flows

Answer 60

Viscosity and density of medication effects its output and particle size

Answer 61

Pentamidine Antibiotics that have different characteristics and viscosity Gentamicin requires 10- 12 lpm to produce adequately small aerosol particles

Answer 62

``` Rapid onset Smaller dose Less systemic side effects Painless Convenient ```

Answer 63

It incorporates air blowers to carry mist to the patient for delivery of bland aerosol therapy or sputum induction.

Answer 64

They use a piezoelectric crystal to produce aerosols. The crystal converts electrical energy into high frequency vibrations which will form oscillation waves and form droplets with break free as fine aerosol particles. Output is directly affected by amplitude setting.

Answer 65

Shake the device and release one or more sprays into the air when the MDI is new or hasn’t been used in a while.

Answer 66

They are categorized by the design of their dose containers.

Answer 67

Assess them every 30 minutes for the first 2 hours then hourly after that for adverse drug responses.

Answer 68

Low temperature decreases the output of the CFC MDI’s. Debris build up on nozzle or actuator orifice reduces the emitted dose.

Answer 69

They are portable, compact, short tx time, and easy to use.

Answer 70

Substance being nebulized Method of generating the aerosol Breathing pattern Inspiratory flow rate

Answer 71

The delivery of aerosolized medications (i.e. bronchodilators, antibiotics and anti-inflammatory agents).

Answer 72

Infection, airway reactivity, pulmonary and systemic effects of bland aerosols, drug concentration changes during nebulization, and eye irritation.

Answer 73

The composition of aerosol, the initial size of particles, the time in suspension, and the ambient condition.

Answer 74

The temperature of the solution increases.

Answer 75

It is a breath-actuated dosing system by which a patient creates the aerosol by drawing air through a dose of finely milled drug powder. The dispersion of powder into respirable particles depends on creation of turbulent flow in inhaler.

Answer 76

cascade impaction and laser diffraction.

Answer 77

designed to collect aerosols of different size ranges on a series of stages or plates. The mass of aerosol deposited on each plate is quantified by drug assay, and a distribution of drug mass across particle sizes is calculated.

Answer 78

a computer is used to estimate the range and frequency of droplet volumes crossing the laser beam.

Answer 79

Because medical aerosols contain particles of many different sizes (heterodisperse), the average particle size is expressed with a measure of central tendency, such as mass median aerodynamic diameter (MMAD) for cascade impaction or volume median diameter (VMD) for laser diffraction. o These measurement techniques of the same aerosol may report different sizes, so it is important to know which measurement is used. o The MMAD and VMD both describe the particle diameter in micrometers (μm).

Answer 80

o The average particle size which is expressed n terms of central tendency  Mass Median Particle Size (MMAD) o Variability of particle size in an aerosol  Geometric Standard Deviation (GSD)

Answer 81

• Mass median aerodynamic diameter (MMAD) is the size where 50% of the mass of particles will be above this size and 50% will be below this size • MMAD is important to determine which nebulizer to use to deliver medication to a target area o If you want deposition into small airways you need to use a nebulizer with a lower MMAD

Answer 82

• The geometric standard deviation (GSD) describes the variability of particle sizes in an aerosol distribution set at 1 standard deviation above or below the median (15.8% and 84.13%). • The greater the GSD, the wider the range of particle sizes produced by a device. • GSD < 1.22, aerosol considered monodispersed = single particle size o Nebulizers that produce monodisperse aerosols are used mainly in laboratory research and in nonmedical industries • GSD > 1.22, aerosol considered heterodispersed = range of particle sizes • Most aerosols used in respiratory care

Answer 83

o Tx nasopharyngeal or oropharyngeal regions e.g. nasal spray for rhinitis

Answer 84

o Deposition to more central airways with significant deposition in oropharyngeal region  Deposits into the large airways, first 6 generations

Answer 85

o Deposition in LRT (last 6 generations) | o More adrenergic receptors in bronchioles (compared to rest of airway) thus increased response with bronchodilators

Answer 86

increased delivery of aerosol to lung parenchyma (alveoli) o Used for anti-infective drugs such as pentamidine where intra-alveolar deposition needed with minimum deposition in airways due to irritation

Answer 87

• Nebulizers generate aerosols from solutions and suspensions.

Answer 88

(1) pneumatic jet nebulizers, (2) USNs, (3) vibrating mesh (VM) nebulizers.

Answer 89

o Small volume nebulizers (SVNs) most commonly used for medical aerosol therapy hold 5 to 20 ml of medication. o Large volume nebulizers, also known as jet nebulizers, hold up to 200 ml and may be used for either bland aerosol therapy or continuous drug administration.

Answer 90

Either pneumatic (gas powered) that utilize a jet-shearing principle for creation of an aerosol

Answer 91

Continuous nebulizer with simple reservoir Continuous nebulizer with collection reservoir bag, Breath-enhanced nebulizer Breath- actuated nebulizer

Answer 92

• The most commonly used SVN is the constant output design. o Aerosol is generated continuously, with 30% to 60% of the nominal dose being trapped as residual volume in the nebulizer, and more than 60% of the emitted dose is wasted to the atmosphere. o Continuous nebulization wastes medication because the aerosol is produced throughout the respiratory cycle and is largely lost to the atmosphere o Patients with an I:E ratio of40:60 (or1:1.5) lose 60% of the aerosol generated to the atmosphere. o If 50% of the total dose is emitted from the nebulizer, and 50% of that aerosol is in the respiratory range and 40% of that is inhaled by the patient, less than 10% deposition is commonly measured in adults receiving continuous nebulizer therapy.

Answer 93

• Aerosolized medication can also be conserved with reservoirs.39 o A reservoir on the expiratory limb of the nebulizer conserves drug aerosol.

Answer 94

o Dead Volume – minimum volume required in the reservoir to aerosolize the drug – 0.5 to 1.0 ml - only 35% to 60% of a drug solution is delivered from a SVN before sputter o Filling Volume and Treatment Time – ideal is 3 to 5 ml at 6 to 8 LPM flow-rate for a treatment time of 10 minutes

Answer 95

• Less technique and device dependent o Minimal coordination • Effective with low inspiratory flows and volumes which improve deposition • Useful in very young, very old, pts in severe distress, debilitated patients • No breath hold is required, although it can’t hurt • Patients in severe distress may have high inspiratory flows…we like the fact we can use a “hands free mask” & just continuously administer medication, eventually some medication reaches our intended target site

Answer 96

``` • Tx times can get lengthy • Contamination • Wet cold spray with mask delivery • External power source o Electrical power or compressed gas ```

Answer 97

• Emergency: o Unable to follow instructions / disoriented o Tachypneic (> 25 bpm) / unstable respiratory pattern o Poor inspiratory capacity o Incapable of breath hold • Patient preference/home use • Formulation of drug

Answer 98

* Many types of disposable SVNs are packaged with a 6-inch (15-cm) piece of aerosol tubing to be used as a reservoir * This may increase inhaled dose by 5% to 10% or increase the inhaled dose from 10% to approximately 11% with the reservoir tube.

Answer 99

* Bag reservoirs hold the aerosol generated during exhalation and allow the small particles to remain in suspension for inhalation with the next breath, while larger particles rain out. * These additions have been attributed with a 30% to 50% increase in inhaled dose. * A collection bag is attached on the expiratory side of the nebulizer “T,” which collects aerosol leaving the SVN when the patient is not actively inhaling. * Some of the aerosol in the bag is inhaled with the next inspiration, increasing total dose efficiency.

Answer 100

• Breath-enhanced nebulizers generate aerosol continuously, using a system of vents and one-way valves to minimize aerosol waste. an inspiratory vent allows the patient to draw in air through the nebulization chamber generating and containing aerosolized drug. • On exhalation, the inlet vent closes, and aerosol exits by a one-way valve near the mouth- piece; this process can increase inhaled mass by 50% over standard continuous nebulizers and reduces aerosol waste to the atmosphere.

Answer 101

• When there is a constant output the drug will be delivered continuously through inspiration and expiration, this means that when expiration is long than inspiration there will be significant losses in the drug amount

Answer 102

• With Dosimetric output the drug will only be delivered during inhalation o Used in PFT laboratories o Sense inspiration and pulse airflow to the jet orifice and transform a conventional nebulizer into a breath actuated system

Answer 103

* It can be difficult to determine when a nebulizer treatment is complete. * Aerosol delivery from a jet nebulizer ceased after the onset of inconsistent nebulization (sputtering) * Aerosol output declined by one-half within 20 seconds of the onset of sputtering. * The concentration of albuterol in the nebulizer cup increased significantly when the aerosol output declined, and further weight loss in the nebulizer was caused primarily by evaporation. Most consider aerosolization past the point of initial nebulizer sputter ineffective.

Answer 104

• Use of an SVN is less technique-dependent and device-dependent than use of a pMDI or DPI delivery system. • Slow inspiratory flow optimizes SVN aerosol deposition. However, deep breathing and breath holding during SVN therapy do little to enhance deposition over normal tidal breathing • Because the nose is an efficient filter of particles larger than 5 μm, many clinicians prefer not to use a mask for SVN therapy. o As long as the patient is mouth breathing, there is little difference in clinical response between therapy given by mouthpiece and therapy given by mask.

Answer 105

• Assess patient for clinical need • Select mask or mouthpiece • Use a conserving system o Thumb port o Breath actuator o Reservoir • Place drug in nebulizer and saline if needed • Set gas flow to 6 to 10 L/min • Coach patient to breath slowly through mouth at normal Vt • Continue treatment until nebulizer sputters • Rinse neb with sterile water • Monitor patient between treatments for adverse effects • Assess outcome

Answer 106

* The CDC recommends that nebulizers be cleaned and disinfected, rinsed with sterile water, or air dried between uses. * Jet SVNs have reservoirs that are open to and positioned below the mouthpiece or mask. This allows secretions from the patient to enter the medication cup, contaminating medication. * Multidose drug containers have been associated with contamination. * After 7 days of nebulizer use five of six multidose containers of medication solutions were found to be contaminated. * Refrigerating solutions and discarding syringes every 24 hours eliminated bacterial contamination. * Use of single dose ampoules have not been associated with contamination of medications. In addition, some recommend one nebulizer for one treatment. * The Cystic Fibrosis Foundation recommends that standard small volume nebulizers should be discarded after each treatment to prevent infection in cyctic fibrosis patients.

Answer 107

• High output with small particles sizes and high aerosol densities • Output is determined by the amplitude setting (some- times user-selected). o The greater the signal amplitude, the greater the nebulizer output.

Answer 108

• Particle size is inversely proportional to the frequency of vibrations. • Frequency is device- specific and is not user-adjustable. o For example, the DeVilbiss (Somerset, PA) Portasonic nebulizer operating at a frequency of 2.25 MHz produces particles with an MMAD of 2.5 μm, whereas the DeVilbiss Pulmosonic nebulizer operating at 1.25 MHz produces particles in the 4- to 6-μm range • Particle size and aerosol density also depend on the source and flow of gas conducting the aerosol to the patient.

Answer 109

Can be placed in line with a ventilator In contrast to SVNs, USNs do not add extra gas flow to the ventilator circuit during use. This feature reduces the need to change and reset ventilator and alarm settings during aerosol administration

Answer 110

* Small size * Rapid nebulization with shorter Tx time * Smaller filling volume * Portability (batteries)

Answer 111

* Expensive * Fragility – lack of durability * Infection control

Answer 112

* Large volume USNs (used mainly for bland aerosol therapy or sputum induction) incorporate air blowers to carry the mist to the patient * Low flow through the USN is associated with higher mist density. * In contrast to jet nebulizers, the temperature of the solution placed in a USN increases during use. * As the temperature increases, the drug concentration increases, and proteins can be denatured.

Answer 113

• In contrast to the larger units, some of these systems do not use a couplant compartment; the medication is placed directly into the manifold on top of the transducer. o The transducer is connected by a cable to a power source, often battery- powered to increase portability. • These devices have no blower; the patient’s inspiratory flow draws the aerosol from the nebulizer into the lung.

Answer 114

wide variety of formulations ranging from bronchodilators to anti-inflammatory agents and antibiotics.

Answer 115

Suspensions such as budesonide may not nebulize well with USNs, because large suspension aerosol particles that are larger than the aerosol particles remain in the medication cup.

Answer 116

• Use of a small volume USN may increase available respirable mass for designs with less residual drug volume than SVNs; this may reduce the need for a large quantity of diluent to ensure delivery of the drugs. o However, sometimes the theoretical advantages of the ultrasonic devices are outweighed by relatively high purchase costs and poor reliability. • Small volume USNs have been used to administer undiluted bronchodilators to patients with severe bronchospasm. Because the nebulizers have minimal residual drug volume, the treatment time is reduced with smaller volumes; however, it may be increased with standard dosing volumes.

Answer 117

Active and Passive

Answer 118

An active VM neb is a dome shaped aperture plate that is surronded with a piezoceramic element When electrical energy is applied it will move the aperture plate up and down creating an electronic pump whih breaks the liquid into fine droplets

Answer 119

The exit velocity of the aerosol is low (<4 m/sec), and the particle size can range from 3 to 4 μm (MMAD), varying with the exit diameter of the apertures

Answer 120

Passive VM nebulizers use a mesh separated from an ultrasonic horn by the liquid solution for nebulization. A piezoelectric transducer vibrates the ultrasonic horn, which pushes fluid through the mesh.

Answer 121

The residual drug volumes with either type of VM nebulizer range from 0.1 to 0.4 ml Because a greater percentage of standard unit doses is emitted as aerosol, care should be exercised when transitioning to these devices to ensure that the higher dose does not create adverse effects.

Answer 122

Low-velocity (soft mist) aerosol, smaller particle size distribution, and systems that minimize residual volume of medication left in the nebulizer substantially improve aerosol device efficiency.

Answer 123

The Respimat soft mist inhaler that uses mechanical energy to create an aerosol from liquid solutions to produce a low-velocity spray (10 mm/sec) that delivers a unit dose of drug in a single actuation. To operate the device, patients twist the body of the device to load an internal spring, place the mouthpiece of the Respimat between the lips, and press a button to release the drug through a uniblock to create the aerosol, which is released over 1.1 to 1.4 seconds, depending on the formulation configuration. The Respimat requires hand-breath coordination on the part of the patient, as does a pMDI, but because of the longer aerosolization time, it seems more likely that the patient will get a greater percent of emitted dose despite coordination issues. Because of the small particle size and low-velocity spray, pulmonary deposition of 40% is independent of inspiratory flows with oral deposition (40%) half the oral deposition with most pMDIs and DPIs (80%).

Answer 124

* A typical SVN is powered by a high-pressure stream of gas directed through a restricted orifice (the jet). * The gas stream leaving the jet passes by the opening of a capillary tube immersed in solution. * Because it produces low lateral pressure at the outlet, the high jet velocity draws the liquid up the capillary tube and into the gas stream, where it is sheared into filaments of liquid that break up into droplets.

Answer 125

Residual volume depends on the position of the SVN. Some SVNs stop producing aerosol when tilted 30 degrees from vertical.

Answer 126

Droplet size and nebulization time are inversely proportional to gas flow through the jet The higher the flow of gas to the nebulizer, the smaller the particle size generated, and the shorter is the time required for nebulization of the full dose. .

Answer 127

Nebulizers that produce smaller particle sizes by use of baffles, such as one-way valves, may reduce total drug output per minute compared with the same nebulizer without baffling and require more time or nominal dose to deliver a standard dose of medication to the lungs.

Answer 128

The higher the pressure or flow, the smaller the particle size, the greater the output, and the shorter the treatment time.

Answer 129

Too low a gas pressure or flow can result in negligible nebulizer output.

Answer 130

• Failure to clean the nebulizer properly caused degradation of performance because of clogging of the jet orifice, reducing the output flow, and buildup of electrostatic charge in the device

Answer 131

Gas density affects both aerosol generation and delivery to the lungs.

Answer 132

The lower the density of the carrier gas, the less aerosol impaction as gas passes through the airways, and the greater the deposition of aerosol in the lungs

Answer 133

When heliox is used to drive a jet nebulizer at standard flow rates, aerosol output is substantially less than with air or O2, and aerosol particles are considerably smaller. • When driving a nebulizer with heliox, twofold to threefold greater flow is required to produce a comparable aerosol output. • Heliox concentrations of 40% or greater have been shown to improve aerosol deposition.37

Answer 134

• Humidity and temperature can affect particle size and the concentration of drug remaining in the nebulizer.

Answer 135

Evaporation of water and adiabatic expansion of gas can reduce the temperature of the aerosol to 10° C less than ambient temperature This cooling may increase solution viscosity and reduce the nebulizer output, while decreasing particle MMAD.

Answer 136

Will increase in size • These particles also can coalesce (stick together), increasing the MMAD further and, in the case of a DPI, can severely compromise the output of respirable particles. • How much these particles enlarge depends primarily on the tonicity of the solution.

Answer 137

• Aerosols generated from isotonic solutions probably maintain their size as they enter the respiratory tract.

Answer 138

Hypertonic solutions tend to enlarge, whereas evaporation can cause hypotonic droplets to evaporate and shrink.

Answer 139

Some drugs, such as antibiotics, are so viscous that they cannot be used effectively for nebulization in some standard SVNs.

Answer 140

A baffle is a surface on which large particles impact and fall out of suspension, whereas smaller particles remain in suspension, reducing the size of particles remaining in the aerosol. droplets that impact baffles in the SVN return to the medication reservoir for nebulization again. Baffles are key elements in nebulizers; well-designed baffling systems decrease both the MMAD (size) and the GSD (range of sizes) of the generated aerosol. • Atomizers operate with the same basic principles as nebulizers without baffling and produce aerosols with larger MMAD and GSD.

Answer 141

Most modern jet nebulizers are powered by high-pressure air or oxygen (O2) provided by a portable compressor, compressed gas cylinder, or 50-psi wall outlet.

Answer 142

• Large volume jet nebulizers can deliver aerosolized drugs to the lung and are particularly useful when traditional dosing strategies are ineffective in the management of severe bronchospasm.

Answer 143

o These nebulizers have a reservoir greater than 200 ml that produces an aerosol with an MMAD of 2.2 to 3.5 μm. • Actual output and particle size vary with the pressure and flow at which the nebulizer operates.

Answer 144

* A concern with continuous bronchodilator therapy (CBT) is increased drug concentration. * Patients receiving CBT need close monitoring for signs of drug toxicity (e.g., tachycardia and tremor).

Answer 145

• A large reservoir nebulizer that is pneumatically powered | o Large amount of the solution and very small particle sizes

Answer 146

• Can hold 300 ml of a solution for long periods of nebulization o These solutions in the reservoir need to be replaced every 24 hours and residual solution should be discarded before adding a new solution

Answer 147

• Used for administering ribavirin (antiviral agent) in the treatment of RSV o There are other ways to treat RSV in infants that may be used. o Ribavarin with a type of interferon is also used to treat Hep C

Answer 148

* Operates on jet shearing principle with baffle, also has drying chamber to further reduce particle size to ~1.3 µm MMD * Nebulizer connected to hood or ventilator for administration to patient

Answer 149

* It incorporates a drying chamber with its own flow control to produce a stable aerosol. * The SPAG reduces medical gas source from the normal 50 pounds per square inch gauge (psig) line pressure to 26 psig with an adjustable regulator. * The regulator is connected to two flowmeters that separately control flow to the nebulizer and flow through the drying chamber. * The nebulizer is located within the glass medication reservoir, the fluid surface and wall of which serve as primary baffles. * As it leaves the medication reservoir, the aerosol enters a long, cylindrical drying chamber. * Here the second (separate) flow of dry gas is added, reducing particle size by evaporation, creating a monodisperse aerosol with an MMAD of 1.2 to 1.4 μm. * Nebulizer flow should be maintained at approximately 7 L/min with total flow from both flowmeters not less than 15 L/min. * The latest model operates consistently even with back pressure and can be used with masks, hoods, tents, or ventilator circuits.

Answer 150

* Two specific problems are associated with SPAG use to deliver ribavirin. * The first is caregiver exposure to the drug aerosol * The other problem occurs only when the SPAG is used to deliver ribavirin through a mechanical ventilator circuit. * Drug precipitation can jam breathing valves or occlude the ventilator circuit. This problem can be overcome by (1) placing a one-way valve between the SPAG and the circuit and (2) filtering out the excess aerosol particles before they reach the exhalation valve, and changing filters frequently to avoid increasing expiratory resistance.44

Answer 151

administer sympathomimetic, anticholinergic, antiinflammatory, and anesthetic aerosols to the upper airway, including nasal pas- sages, pharynx, and larynx • These agents are used to manage upper airway inflammation and rhinitis, to provide local anesthesia, and to achieve systemic effects.

Answer 152

Will generate relatively low pressure and does not have baffles, it produces an aerosol with large particle size (high MMAD and GSD), ideal for upper airway deposition. Deposition with the hand-bulb atomizer applied to the nose occurs mostly in the anterior nasal passages with clearance to the nasopharynx. The 100-mcl puffs appear to deposit more medication than 50-mcl puffs, and deposition to a greater surface area occurs with a 35-degree spray angle than with a 60-degree angle.

Answer 153

• MDI are the most common medication aerosol medication device as when they are properly used they are at least as effect as other drug nebulizers for drug delivery o For this reason, pMDIs often are the preferred method for delivering bronchodilators to spontaneously breathing patients and patients who are intubated and undergoing mechanical ventilation

Answer 154

A small pressurized canister that contains a prescription drug (a micronized powder or aqueous solution) in a volatile propellant combined with a surfactant and dispersing agent

Answer 155

2- 6 µm MMAD the initial velocity and dispersion of the aerosol plume generate larger particles that decrease in size as they leave the pMDI, resulting in approximately 80% of the dose leaving the actuator to impact and become deposited in the oropharynx.

Answer 156

It seems light-You can hold the canister next to your ear and shake it several times. If it has medicine, you'll hear and feel the liquid contents swishing back and forth. There is no movement of particles The counter is at 0

Answer 157

• Due to the initial velocity and dispersion of an aerosol 80% of a dose leaving the actuator will impact and deposition in the oropharynx o Pulmonary deposition ranges from 10-20%

Answer 158

Hydrofluoroalkane (HFA)-134a is a environment-friendly and clinically safe propellant In addition to the propellant, pMDIs use dispersal agents to improve drug delivery by keeping the drug in suspension. The most common dispersal agents are surfactants, such as soy lecithin, sorbitan trioleate, and oleic acid. These agents help keep the drug suspended in the propellant and lubricate the valve mechanism but may also cause adverse responses (coughing or wheezing) in some patients.

Answer 159

* When the canister is inverted (nozzle down) and placed in its actuator, or “boot,” the volatile suspension fills a metering chamber that controls the amount of drug delivered. * Pressing down on the canister aligns a hole in the metering valve with the metering chamber * The high propellant vapor pressure quickly forces the metered dose out through this hole and through the actuator nozzle. * As the liquid suspension is forced out of the pMDI, it forms a plume, within which the propellants vaporize. Initially, the velocity of this plume is high (approximately 15 m/sec). * The output volume of pMDIs ranges from 30 to 100 mcl.

Answer 160

* Every pMDI should be primed by shaking and actuating the device to atmosphere one to four times (see label for the specific device) before initial use and after storage. * Without priming, the initial dose actuated from a new pMDI canister contains less active substance than subsequent actuations.

Answer 161

* This “loss of dose” from a pMDI occurs when drug particles rise to the top of the canister over time (“cream”). * A reduction in emitted dose with the first actuation commonly occurs with a pMDI after storage, particularly with the valve pointed in the downward position. * Loss of prime is related to valve design and occurs when propellant leaks out of the metering chamber during periods of nonuse (e.g., 4 hours). * The result is reduced pressure and drug released with the next actuation.23 * Improved designs of metering valves developed for use with HFA propellants reduce these losses.

Answer 162

• Some patients exhibit a “cold Freon effect,” which occurs when the cold aerosol plume reaches the back of the mouth and the patient stops inhaling. All of these problems reduce aerosol delivery to the lung to the point that the patient does not benefit from the medication, but they can be corrected entirely or in part by use of the proper pMDI accessory device.

Answer 163

• Use of anticholinergic agents has been associated with increased ocular pressure, which could be dangerous for patients with glaucoma. For avoidance of ocular exposure, the drug manufacturer recommends patients use the closed-mouth technique with ipratropium.

Answer 164

1. Warm the pMDI to hand or body temperature and shake it vigorously 2. Before use of a new pMDI and when the pMDI has not been used for several days prime the pMDI by pointing it into the air (away from people) and actuating a couple of times 3. Assemble the apparatus and uncap the mouthpiece assuring there are no losse objects in the device 4. Open mouth technique. Open you mouth wide, keeping tongue down Hold the pMDI with the canister oriented donward and the outlet aimed at yout mouth. Position the pMDI ~4cm (2 finger breaths) away from your mouth 5. Closed mouth technique. Place mouthpiece between lips with tongue out of the path of the outlet 6. Breathe out normally 7. As you slowly begin to breath in (<0.5 L/sec) actuate the pMDI 8. Continue inspiration to total lung capacity 9. Hodl your breath for up to 10 seconds. Then relax, and breath normally 10. Wait 1 minute between puffs 11. Dissassemble the apparatus and recap the mouthpiece

Answer 165

``` o Drug o Propellant o Canister o Metering valve o Actuator with mouthpiece ```

Answer 166

• When inverted an placed in a actuator the suspension will fill the metering valve chamber • Then the canister is depressed into the actuator the drug/propellant mixture in the metering valve will be release under pressure • The liquid propellant is ejected from the pressurized valve and will rapidly expand and vaporizes (ambient pressure) o Shatters liquid stream into an aerosol o Pressure in canister is specific to medication formulation • Upon release, metering valve refills with drug- propellant mixture from canister and is ready for next discharge

Answer 167

* Low temperature (<10° C) decreases the output of CFC pMDIs. * Patients with cold air–induced bronchospasm who keep their pMDIs in outer coat pockets when outside in cold winter weather may receive only a small percentage of drug compared with that administered with the same pMDI at 25° C. * This problem has been less serious with the newer HFA pMDIs.

Answer 168

• Rapid actuations can lead to turbulence and coalescence of particles o Actuations – at least 30 seconds apart

Answer 169

Changes in drug concentration concentration in first discharge, if standing unused o Drug suspension can separate from propellant when stored unused (creaming)

Answer 170

o Little or no drug discharged on actuation o Can be felt and heard by user o Usually takes days and weeks to occur o Regular use of MDI prevents this!

Answer 171

The particle size of aerosolized drug released controlled by: Vapor pressure of propellant blend- Increased vapor pressure will decrease particle size Diameter of actuator opening-Decreased actuator opening will decrease particle size

Answer 172

* Aerosol drug delivery is influenced by nozzle size and cleanliness. * Nozzle size is pMDI- specific. * As debris builds up on the nozzle or actuator orifice, the emitted dose is reduced.24 * Manufacturer recommendations should be followed for cleaning. pMDI canisters should never be placed under water

Answer 173

* Priming is defined as shaking the device and releasing one or more sprays into the air when the pMDI is new or has not been used for awhile. * It is done to mix the drug and the propellant, which can separate in the canister over time. Priming is required to provide an adequate dose, according to the manufacturer’s guidelines.

Answer 174

hand- breathing coordination required (if no holding chamber used) • Canister depletion difficult to determine accurately • Possible reactions to propellant • High oropharyngeal impaction and loss if holding chamber not used • Foreign body aspiration of coins and debris from mouth piece o

Answer 175

• Simple extension devices that puts distance between MDI and patient’s mouth Were designed to simplify the complex coordination of aiming, actuation and breathing with an MDI. • MDI accessory devices designed to decrease initial velocity of particles released from MDI before reaching oropharynx decrease oropharyngeal deposition

Answer 176

o Which will reduce the initial forward velocity of the pMDI droplets, which occurs with partial evaporation of propellant in the time the aerosol traverses the length of the spacer.  The reduction in initial forward velocity decreases the number of nonrespirable particles reaching the airway.  The increase of space and time will also allow for a decrease in size through vaporization of the propellant and evaporation of the initial large particle sizes • The MMAD of the aerosol emitted from the pMDI exiting a spacer decreases approximately 25%, whereas the fraction containing particles less than 5 μm in diameter increases. o Will also simplify the coordination for the user

Answer 177

• Multiple actuations of one or more drugs into a spacer reduce both the total dose and the respirable dose of drug available for inhalation as respirable particles containing drugs will settle out and become deposited within the device cause a whitish buildup on the inner chamber walls. o The extent of these losses may vary for different drugs and spacer designs.23 o This residual drug poses no risk to the patient but should be be rinsed out periodically.

Answer 178

• Plastic spacers decrease drug output due to the presence of an electrostatic charge. With these devices, a buildup of material can be seen on the walls of the chamber. o As more material builds up on the wall of the chamber, the charge is dissipated, and more drug is inhaled by the patient. o Washing the chamber with water (without soap) causes the electrostatic charge to be reestablished, making the device less effective for the next few puffs, until the static charge in the chamber (which attracts small particles) is again reduced.32 o Use of conductive metal or nonelectrostatic plastic chambers or washing the plastic chamber periodically with deionizing detergent (liquid dishwashing soap) can overcome the loss of fine-particle mass owing to electrostatic charge and increase the inhaled mass from 20% to 50% of the emitted dose of the pMDI, even in children o The effect of washing the chamber with conventional dishwashing soap reduces this static charge for up to 30 days. o All manufacturers recommend that VHCs and spacers should be cleaned regularly, typically monthly using dilute liquid dishwashing soap, with or without rinsing, and allowing them to air dry.

Answer 179

• VHCs with masks are available for use in the care of infants, children, and adults. These units allow effective administration of aerosol from a pMDI to patients who are unable to use a mouthpiece device (because of their size, age, coordination, or mentation) o Exhalation valves in a face mask attached to a spacer device must also provide low resistance. Issues of spacer volume, VT, frequency of breathing, and mechanical dead space between the spacer and mouth are of particular concern when these devices are used by children.32

Answer 180

o Small volume adapters o Open tube designs o Bag reservoirs o Valved holding chambers

Answer 181

o Global term for spacers and holding chambers

Answer 182

o Simple valve-less extension device o Extend the distance from the aerosol spray away from mouth  This distance allows the aerosol plume to expand and the propellants to evaporate before the medication reaches the oropharynx.  The larger particles will impact on the walls of the spacer  This will reduce oropharyngeal impaction and increase pulmonary deposition o Proper use of a simple open-tube spacer still requires some hand-breath coordination because a momentary delay between triggering and inhaling the discharged spray results in a substantial loss of drug and reduced lung delivery. o Exhalation into a simple spacer after pMDI actuation clears the aerosol from the device and wastes most of the dose to the atmosphere. This reduction in dose also occurs with small volume reverse-flow design spacers if there is no provision for “holding” the aerosol in the device.29

Answer 183

o A spacer device with addition of one way valves • The one way valve must be able to withstand the initial pressure from the pMDI when the device is triggered to retain aerosol and have sufficiently low resistance to open readily when the user inhales, in particular, when the user is a child or an infant. o Contain and hold aerosol until inspiration occurs o This allows patients with a small VT to empty the aerosol from the chamber over two or more successive breaths. o Provides less oropharyngeal deposition, higher respirable drug dosages, and better protection from poor hand-breath coordination than simple spacers. o VHCs protect the patient from poor hand-breath coordination, with exhaled gas venting to the atmosphere, allowing aerosol to remain in the chamber available to be inhaled with the next breath. VHCs allow infants, small children, and adults who cannot control their breathing pattern to be treated effectively with pMDIs. o A simple tube spacer may reduce oral deposition by 90%, whereas a valved holding chamber can reduce oral deposition by 99%. o The placement of a valve between the pMDI, the chamber, and the mouthpiece works like a baffle reducing the size of particles inhaled.

Answer 184

1. Warm the pMDI to hand or body temperature and shake it vigorously 2. Before use of a new pMDI and when the pMDI has not been used for several days prime the pMDI by pointing it into the air (away from people) and actuating a couple of times 3. Assemble the apparatus and uncap the mouthpiece assuring there are no losse objects in the device 4. Place pMDI in holding chamberinlet, position the chamber outlet in the mouth or place the mask over the nose and mouth and encourage the patient to breath through their mouth while visually inspecting for valve function 5. With normal breathing actuate the pMDI once and have the patient breathe through the device for 3-7 breaths (3 breaths for adults and 7 for infants) 6. Allow 30-60 seconds between actutation *With a cooperative patient synchronizing actuation at the beginning of a larger breath with breath holding may be encouraged. However, the maneuter has not been shon to increase lcinical response to inhaled bronchodilators

Answer 185

After the number of label doses has been administered, the pMDI may seem to give another 20 to 60 doses, which may deliver little or no medications as the doses “tail-off.” The tail-off effect refers to variability in the amount of drug dispensed toward the end of the life of the canister. The result of tail-off is swings from normal to almost no dose emitted from one breath to the next with no reliable indicator to the user.

Answer 186

• These devices are breath-actuated (do not require a propellant), with turbulent air flow from the inspiratory effort of the user providing the power to create an aerosol of the fine particles of drug o Self-generated flows of between 30 – 90 lpm are needed for drug deposition • Flow from user creates an aerosol of microfine solid particles of drug as it is inhaled through mouth piece • Are as effective as MDIs for deposition & drug response.

Answer 187

Diskus Turbuhaler HandiHaler

Answer 188

Most passive DPIs require the use of a carrier substance (lactose or glucose) mixed into the drug to enable the drug powder to deaggregate more readily and flow out of the device Reactions to lactose or glucose are fewer than reactions to the surfactants and propellants in MDIs, but the amount of these substances is substantially greater than the amount of the drug The particle size of the dry powder particles of drug ranges from 1 to 3 μm. However, the size of the lactose or glucose particles can range from approximately 20 to 65 μm, so most of the carrier (≤80%) is deposited in the oropharynx.

Answer 189

Unit-dose DPI Multiple unit-dose DPI Multiple dose drug reservoir DPI.

Answer 190

* Optimal performance for each DPI design occurs at a specific inspiratory flow rate. * The higher the resistance or the greater the flow requirement of a DPI device, the more difficult it is for a compromised or young patient to generate inspiratory flow sufficient to obtain the maximum dose of drug from the device. If a patient does not inhale at the optimal inspiratory flow rate for a particular device, delivery to the lung decreases as the dose of drug dispensed decreases and the particle size of the powder aerosol increases

Answer 191

* The emitted dose of DPI decreases in a humid environment, likely because of powder clumping. * The longer the exposure and the greater the level of absolute humidity, the lower the dose emitted.

Answer 192

Passive, or patient-driven, DPIs rely on the patient’s inspiratory effort to dispense the dose. The result is differences in lung delivery and clinical response. Active or powered DPI devices, which deaggregate the powder before inhalation, are independent of patient effort. Active DPIs use an energy source to deaggregate the powder and suspend the powder into an aerosol, allowing the dose to be suspended independent of patient inspiratory flow rates.

Answer 193

Because infants, small children (<5 years old) and patients who are unable to follow instructions cannot develop inspiratory flows his high, these patients cannot use DPIs. Because patients with severe airway obstruction may be unable to achieve the required flow, they should not use DPIs during acute bronchospasm.

Answer 194

Exhalation into a DPI before inspiration can result in loss of drug delivery to the lung.

Answer 195

Although the DPI may require cleaning in accordance with the product label, the device should never be submerged in water. Moisture in the device dramatically reduces available dose.

Answer 196

• The most critical factor in using a passive DPI is the need for high inspiratory flow. o Patients must generate an inspiratory flow rate of at least 40 to 60 L/min to produce a respirable powder aerosol.

Answer 197

disposable multidose DPI in which the drug is stored in double-foil blister strips. • The device has a 3-step technique (open-inhale-close) and provides auditory feedback with the opening of the inhaler that results in loading the dose and an advancement in the dose counter. • When a patient does not inhale the dose from the Ellipta®, the drug is dumped internally to prevent overdosing.

Answer 198

Incruse Ellipta® delivers umeclidinium, a long-acting muscarinic antagonist that is used in the treatment of COPD o BreoTM Ellipta® has a combination of fluticasone furoate and vilanterol (long- acting β2-agonist) o AnoroTM Ellipta® includes a combination of umeclidinium and vilanterol.

Answer 199

* Pre- loaded doses * Each dose contained in foil blister which is advanced and opened as inhaler is used * The doses are contained in 60 sealed pockets alone the aluminum foil strip that is advanced along the lever * As the drug pocket reaches the mouthpiece the cover is peeled away making the drug available for inhalation * There is a dose counter indicating the number of doses remianing

Answer 200

``` • Powder preparation preloaded in device o Opened by rotating grip or thumb wheel • High number of doses o 60 to 200 • May have a counter incorporated or gives a warning indication when there are ~20 doses left • Effective at flow rates ~ 40 lpm 30-60 • Desiccating agent present ```

Answer 201

* Contains single- dose powder preparation of drug in gelatin capsule * Capsule inserted into device & punctured to release powder prior to inhalation * Carrier substance (glucose or lactose) improves flow properties of powder mixture and provides suitable volume to unit dose

Answer 202

* Small and portable * Short preparation and administration time * Less hand- breathing coordination * No propellants (thus environmentally friendly) * No ‘cold freon effect’ causing bronchoconstriction or inhibiting full inspiration * Count of remaining drug doses relatively easy * No extension device needed

Answer 203

* Patients not as aware of dose inhaled thus may distrust delivery * Possible reaction to glucose or lactose carrier substance * High inspiratory flow rates needed * Most of carrier impacts in oropharynx & can cause irritation

Answer 204

The dose by each delivery method that produces an equivalent degree of therapeutic effect

Answer 205

~ 1:2 2.5 mg SVN=5 puff MDI 250 mg SVN=4 puff MDI

Answer 206

* IV Indications – giving certain agents systemically vs inhaled or instilled for direct systemic effect, more immediate response (rapid tissue dispersal) * Systemic drug delivery is effective for agents being used for systemic effect: i.e.: using a vasopressor to increase blood pressure. * Agents that are to be used for lung effect are most often given via inhalation for efficiency without systemic side effects.

Answer 207

* Mechanical ventilation * Artificial airways * Reduced airway size (infants and children) * Severe airway obstruction * Poor patient compliance and Technique * Limitation of specific delivery device * Exhalation into device can result in loss of drug

Answer 208

* Able to follow instructions / demonstrate correct use * Adequate inspiratory capacity * Capable of breath hold * Stable respiratory pattern * Drug available in MDI form

Answer 209

• Drug available in DPI form • Poor MDI coordination • Sensitive to propellants • Capable of generating high inspiratory flow rates (> 30-60 lpm) depending on drug o High inspiratory flow is the most critical factor for DPI o Should not be used with patients unable to generate high flows such as small children and patients with acute bronchospasm • Need accurate dose count monitoring • Strive for consistency with devices. • High humidity can affect DPI drug availability o Hygroscopic particles will clump together when exposed to high humidity increasing particle size

Answer 210

Epoprostenol (Veletri®), epoprostenol sodium (Flolan®), iloprost (Ventavis®), and treprostinil (Tyvaso) are inhaled prostacyclins used for treatment of pulmonary arterial hypertension. Epoprostenol administration is associated with positive effects on symptoms, hemodynamics, exercise capacity, disease progression and survival,it has not been approved for inhalation, and due to its short half-life of 30 to 90 seconds, requires continuous nebulization. In contrast, iloprost and treprostinil are approved for inhalation with a half-life of 60 to 90 minutes, allowing more convenient dosing to ambulatory patients.

Answer 211

o SVN, USN, VM nebulizer, and pMDI with third-party adapter.

Answer 212

Will be similar to non-intubated patients

Answer 213

The process by which the aerosol suspension changes over time.

Answer 214

A pressurized canister containing the prescribed drug in a volatile propellant combined with surfactant and a dispersing agent.

Answer 215

An increase in peak flow of greater than 10% with a goal of at least 50%.

Answer 216

80% of the aerosol hits the back of the throat depositing the medication in the oropharynx.

Answer 217

Higher aerosols outputs and higher aerosol densities than conventional jet nebulizers.

Answer 218

An adverse reaction to the medication.

Answer 219

The greater the GSD, the wider the range of particle sizes and therefore a more dispersed aerosol.

Answer 220

A spacer is valve-less and just adds distance from the point of discharge to the mouth. A holding chamber has valves for holding the medication.

Answer 221

In the circuit close to the patient’s airway.

Answer 222

To mix the drug and propellant and to ensure that an adequate dose is provided.

Answer 223

For treatment of refractory bronchospasm. Nebulized albuterol is dosed at 5-20mg/hour.

Answer 224

(1) Unit-Dose DPI, (2) Multiple unit-dose DPI, and (3) Multiple Dose Drug Reservoir DPI.

Answer 225

Evaporation or hygroscopic water absorption

Answer 226

The process by which an aerosol suspension changes over time

Answer 227

The SPAG was manufactured by ICN Pharmaceuticals specifically for administration of ribavirin (Virazole) to infants with respiratory syncytial virus infection. It incorporates a drying chamber with its own flow control to produce a stable aerosol.

Answer 228

A surface on which large particles impact and fall out of suspension, whereas smaller particles remain in suspension, reducing the size of particles remaining in the aerosol.

Answer 229

They should be primed by shaking and actuating the device to atmosphere one to four times. Without the priming, the initial dose actuated from a new pMDI canister contains less active substance than subsequent actuations. You should waste a single does when it has not been used for 4-6 hours.

Answer 230

An aerosol device that is responsive to the patient’s inspiratory effort and reduces or eliminates aerosol generation during exhalation. They can generate aerosol only during inspiration. This eliminates the waste of aerosol during exhalation and increases the delivered dose threefold or more over continuous and breath-enhanced nebulizers.

Answer 231

A variation of a pMDI that incorporates a trigger that is activated during inhalation. This trigger reduces the need for the patient or caregiver to coordinate MDI actuation with inhalation.

Answer 232

They are nebulizers that entrain room air in direct relationship to the inspiratory flow of the patient. They generate aerosol continuously, using a system of vents and one-way valves to minimize aerosol waste.

Answer 233

They should be cleaned and disinfected, or rinsed with sterile water, and air-dried between uses.

Answer 234

They are gaseous chemical compounds that were originally used to power metered dose inhalers but have been phased out of use.

Answer 235

They should be cleaned regularly, typically monthly, as recommended by the manufacturer. Use of dilute liquid dishwashing soap, with or without rinsing, and allowing to air dry are recommended.

Answer 236

It varies according to both patient technique and device design. For these reasons, the best approach to aerosol drug therapy is to use an assessment-based protocol that emphasizes individually tailored therapy modified according to patient response.

Answer 237

Reactive bronchospasm and increased airway resistance.

Answer 238

Possible degradation of the performance of the plastic device over multiple uses

Answer 239

They should not be used for the management of acute bronchospasm.

Answer 240

The higher the flow of gas to the nebulizer, the smaller the particle size generated, and the shorter is the time required for nebulization of the full dose.

Answer 241

They can be inhaled by anyone in the vicinity of the treatment. The risk imposed by this environmental exposure is clear and is associated with a range of drugs and patients with infectious disease. Pentamidine and ribavirin were associated with health risks to health care providers even when used in conjunction with filters on exhalation ports of nebulizers, containment and scavenger systems, and high-efficiency particulate air (HEPA) filter hoods and ventilation systems.

Answer 242

Typically a breath-actuated dosing system. The patient creates the aerosol by drawing air though a dose of finely milled drug powder with sufficient force to disperse and suspend the powder in the air. The dispersion of the powder into respirable particles depends on the creation of turbulent flow in the inhaler.

Answer 243

It can result in the loss of drug delivery to the lungs.

Answer 244

An aerosol administered via face mask which causes the drug to be deposited in the eyes.

Answer 245

It is a pressurized canister that contains the prescribed drug in a volatile propellant combined with a surfactant and dispersing agent. It is used to administer bronchodilators, anticholinergics, and steroids. They are easy to use but are commonly misused.

Answer 246

An inadequate amount of drug reaches the airway. To determine the “best” dose for patients with moderate obstruction, the respiratory therapist should conduct a dose-response titration.

Answer 247

An increase in drug concentration can be adversely given. Patients receiving CBT needs close monitoring for signs of drug toxicity (e.g., tachycardia and tremor) The precise amount of drugs delivered to the patient’s airways

Answer 248

The patient’s clinical response to aerosol drug therapy including the desired therapeutic effects and any unwanted adverse effects.

Answer 249

Nebulizers should be sterilized between patients, nebulizers should frequently be replaced with disinfected or sterile units or rinsed with sterile water (not tap water) and air dried every 24 hours.

Answer 250

Also known as dead volume, it is the medication that remains in the SVN after the device stops generating aerosol and “runs dry.” The residual volume of a 3-ml dose can range from 0.5 to more than 2.2 ml, which can be more than two-thirds of the total dose. Residual volume also depends on the position of the SVN.

Answer 251

Severity of airway obstruction but must not be confused with bronchodilator overdose.

Answer 252

It involves giving an initial 4 puffs (90 mcg/puff) at 1-minute intervals through a pMDI with a holding chamber. After 5 minutes, if airway obstruction is not relieved, the respiratory therapist gives 1 puff per minute until symptoms are relieved, heart rate increases to more than 20 beats/min, tremors increase, or 12 puffs are delivered. The best dose is the dose that provides maximum relief of symptoms and the highest PEFR without side effects.

Answer 253

They are most commonly used for medical aerosol therapy and hold 5 to 20 ml of medication.

Answer 254

Bronchodilators to anti-inflammatory agents and antibiotics.

Answer 255

It is unwise because not all patients can perform these maneuvers. Other components of patient assessment useful in evaluating bronchodilator therapy include patient interviewing and observation, measurement of vital signs, auscultation, blood gas analysis, and oximetry.

Answer 256

A spacer is a simple valve-less extension device that adds distance between the MDI outlet and the patient’s mouth. This distance allows the aerosol plume to expand and the propellants to evaporate before the medication reaches the oropharynx.

Answer 257

They are MDI accessory devices designed to reduce both oropharyngeal deposition and the need for hand-breath coordination. All spacers add distance between the MDI and the mouth, reducing the initial forward velocity of the MDI droplets. It also helps to reduce foul taste of the medication.

Answer 258

It results in greater deposition of aerosol from an SVN than occurs with positive pressure breaths (e.g., intermittent positive pressure ventilation). This mode of ventilation reduces aerosol deposition more than 30% compared with the effect of spontaneously inhaled aerosols.

Answer 259

Slow inspiratory flow optimizes SVN aerosol deposition. Deep breathing and breath holding during SVN therapy do little to enhance deposition over normal tidal breathing. As long as the patient is mouth breathing, there is little difference in clinical response between therapy given by mouthpiece and therapy given by mask.

Answer 260

(1) Pneumatic jet nebulizers, (2) USNs, and (3) VM nebulizers.

Answer 261

Manufacturers recommended 30 seconds to 1 minute between actuations. Very rapid actuations of multiple puffs per breath reduces inhaled drug per puff.

Answer 262

They should rinse the mouth after steroid use.

Answer 263

(1) Caregiver exposure to the drug aerosol, and (2) Drug precipitation can jam breathing valves or occlude the ventilator circuit.

Answer 264

It is powered by a high-pressure stream of gas directed through a restricted orifice (the jet). The gas stream leaving the jet passes by the opening of a capillary tube immersed in solution. Because it produces low lateral pressure at the outlet, the high jet velocity draws the liquid up the capillary tube and into the gas stream, where it is sheared into filaments of liquid that break up into droplets.

Answer 265

They dispense individual doses of the drug from punctured gelatin capsules.

Answer 266

To generate an aerosol. The crystal transducer converts an electrical signal into high-frequency (1.2- to 2.4-MHz) acoustic vibrations. These vibrations are focused in the liquid above the transducer, where they disrupt the surface and create oscillation waves. If the frequency of the signal is high enough and its amplitude strong enough, the oscillation waves form a standing wave that generates a geyser of droplets that break free as fine aerosol particles.

Answer 267

They are used to protect the patient from poor hand-breath coordination, with exhaled gas venting to the atmosphere, allowing aerosol to remain in the chamber available to be inhaled with the next breath. They allow infants, small children, and adults who cannot control their breathing pattern to be treated effectively with MDIs.

Answer 268

The median diameter of an aerosol particle measured in units of volume.

Answer 269

They decrease both the MMAD (size) and the GSD (range of sizes) of the generated aerosol.

Answer 270

It is provided in a private room. The room should be equipped for negative pressure ventilation with adequate air exchanges (at least six per hour) to clear the room of residual aerosols before the next treatment. HEPA filters should be used to filter room or tent exhaust, or the aerosol should be scavenged to the outside.

Answer 271

To deliver greater than 10% of the dose to both infants and adults. A pMDI with an adapter placed immediately proximal to the endotracheal tube achieved similar results in adult patients ventilated via high-frequency oscillatory ventilation.

Answer 272

It is reduced as the flow increases, whereas placement of a VM nebulizer near the ventilator increases delivery.

Answer 273

To determine the remaining drug in a MDI other than manually keeping a log of every dose taken.

Answer 274

They are inexpensive, light, compact, resistant to moisture, They provide a quick delivery of drugs, as well as precise and consistent doses. They are available with most anti-asthmatic drugs.

Answer 275

Some patients have difficulty in the coordination of activation and inspiration. It can be time-consuming to teach. There is also the cold-freon effect, which is the inability to continue to breathe when the propellant is released into mouth.

Answer 276

Children under the age of 5 and patients unable to generate a high air flow. They also may not work as well in high humidity environments.

Answer 277

Coordinate firing the MDI with the beginning of the ventilator inspiration.

Answer 278

Atomizers don’t have baffles. They are usually powered by a hand-squeezed bulb. Because the particles are larger, the drug deposits in the upper airway. You might deliver a local anesthetic through an atomizer prior to bronchoscopy.

Answer 279

60 L/minute

Answer 280

No need to activate coordination with inspiration, Increases drug deposition in the lungs, Reduces drug deposition in the mouth, Can be used in children with a face mask, and Decreases the incidence of oral thrush.

Answer 281

Cools during operation, provides a small aerosol particle size, and is less expensive.

Answer 282

In the lower airways.

Answer 283

Give 2 to 5 times the normal dose.

Answer 284

6 to 8 L/minute.

Answer 285

Heats up during operation, Larger aerosol particles, More expensive, and Less noise.

Answer 286

Corticosteroids to reduce oropharyngeal deposition.

Answer 287

0.2 to 1.0 ml/minute

Answer 288

Bronchospasm, Over-hydration, Overheating of inspired gases, Delivery of contaminated aerosol, and Tubing condensation draining into the airway.

Answer 289

Atomizers and Nebulizers.

Answer 290

Upper airways.

Answer 291

Central airways.

Answer 292

Brownian diffusion.

Answer 293

Sterilize the nebulizers between patients, Frequently replace in-use units, and rinse nebulizers with sterile water.

Answer 294

Measure pre and post peak flow and/or %forced expiratory volume in 1 second, Auscultate for adventitious breath sounds, Observe patient’s response, and Communicate with the patient during therapy.

Answer 295

Propellant

Answer 296

The canister should be warmed to hand or body temperature and the canister should be vigorously shaken.

Answer 297

Patients that are in acute distress, infants and young children, and elderly persons.

Answer 298

The high flows necessary for actuation.

Answer 299

MDI and SVN.

Answer 300

A one-way inspiratory valve.

Answer 301

A patient that is likely to develop acute severe bronchospasm.

Answer 302

MDI, holding chamber, and mask.

Answer 303

Generate inspiratory flows of 60 L/min or higher.

Answer 304

Infants and children under 5, patient’s with an acute bronchospastic episode.

Answer 305

Dry powder inhaler.

Answer 306

Reposition the patient so that the SVN is more upright.

Answer 307

The treatment time becomes shorter, Particle size becomes smaller, Aerosol output becomes greater.

Answer 308

Rinse the SVN with sterile water; air dry.

Answer 309

SPAG – Small particle aerosol generator.

Answer 310

Caregiver exposure to drug aerosol, drug precipitation in ventilator circuits.

Answer 311

DPI, and MDI with holding chamber.

Answer 312

Increasing airway obstruction.

Answer 313

When the patient’s symptoms are relieved or when the PEFR/FEV1 in 1 second exceeds 70% of their personal best.

Answer 314

Good patient education.

Answer 315

Have the patient provide a repeat or return demonstration.

Answer 316

The beginning of inspiration.

Aerosol Therapy Flashcards

(349 cards)