1410 Aerosol Therapy and Medication Delivery

A comprehensive set of flashcards covering key concepts in aerosol therapy and medication delivery, including mechanisms, advantages, disadvantages, and assessment methods.

What is an aerosol

Liquid or solid particles suspended in a gas

What is aerosol stability?

Ability for particle to remain suspended

Factors determining aerosol particle size

Substance being nebulized, nebulizer characteristics and method used, and environmental conditions.

>5 microns - deposited before reaching the Carina

>1 micron - may reach alveoli and be exhaled out

10% aerosolized drug reaches alveoli 

Hazards of Aerosol Drug Therapy 

PRIMARY HAZARD: A reaction to the drug being aerosolized

Infection

Airway reactivity

Drug reconstitution

eye irritation

secondhand exposure

What is MDI and how does a MDI work?

“Metered Dose Inhaler” 

Pressurized canister with medication, propellant, dispersing agent.

Canister inverted down, placed in actuator, suspension fills chamber

When canister depressed mixture discharges and produces and aerosol

Propellent evaporates

Dispersal agents help keep drug suspended 

Advantages of MDI

No prep

Compact

Portable

Extra note: may be used with mechanical ventilator

Disadvantages of MDI

Requires coordination and frequent instruction

High oropharyngeal deposition

Risk of abuse (counters will be required by FDA)

Difficult to deliver high dose

Expensive 

Purpose of spacers/valved holding chambers

Design reduces oropharyngeal deposition/cold Freon effect/foul taste - can be used with mask or mouthpiece.

Advantages: Decreased need for coordination, Increases deposition of medication

Disadvantages: Less portable, extra money, more to clean 

DPI (Dry Powder Inhaler)

Breath-Actuated metered dose system that doesn’t require a propellent

The force of the patient’s inhalation draws air through the powder blend—usually a drug mixed with lactose or glucose—which breaks up the powder and turns it into a breathable aerosol.

Types: Unit dose DPI: Handihaler, Aerolizer

Multiple dose DPI - diskhaler, twisthaler, flexhaler, diskus

May have blister packs (capsules) tape systems, or reservoir powder system 

Inspiratory flow rate for optimal DPI performance

>60 L/min.

Advantages of DPIs

Accurate dose

Easy to use

Less coordination

Disadvantages of DPIs

Many types - cause confusion - Ellipta - easiest

Ambient humidity can affect delivery

Unable to use with trach/intubated patient

Patient can’t generate adequate inspiratory flow

Some are expensive

Power source for pneumatic nebulizers

High-pressure air or O2 at 50 psi, 6–8 LPM flow.

Indications for jet nebulizer use

Poor coordination, ineffective breathing, large doses, mechanical ventilation.

Advantages of jet nebulizers

Less coordination, high doses possible, inexpensive.

Disadvantages of jet nebulizers

Wasteful, contamination risk, long treatment time.

Purpose of SPAG

To deliver ribavirin (Virazole).

Ultrasonic nebulizers are known for

High output, little dead space, no need to dilute.

Examples of vibrating mesh/smart nebulizers

Aeroneb, Aerogen, AERx, Respimat, I-Neb, Respiraguard.

Racemic Epinephrine purpose (adrenergic bronchodilator)

used for vasoconstriction/upper airway inflammation or edema,; side effects: tachycardia, tremors, palpitations, hypertension, restlessness, fear and anxiety, tremor, dizziness, tolerance

Correct order for multiple meds administration

Bronchodilator → Corticosteroid → Others.

Pneumatic Jet Nebulizer (AKA) SVN, Unassisted bronchodilator therapy (UABD), Hand-Held Nebulizers (HHN), Med-Nebs, Updrafts (UD)

SVN - Most popular mode of treatment

Powered by high pressure air or O2 by 50psi wall outlet and flow meter, compressed gas cylinder or portable compressor

Stream of gas through a jet →draws liquid up into gas stream, broken into droplets → baffle knocks large particles out of suspension

6-8 LPM - not all meds nebulized, runs continuously during exhale, meds wasted 

Mask, mouthpiece, blowby

Can be used with Vent

Rinse with sterile water in between

Indications:

        Patient can’t coordinate MDI/DPI, can’t take deep breath

Advantages: Less coordination, high doses possible, inexpensive

Disadvantages: wasteful, drug prep required, contamination/infection, pressurized gas source required

long treatment time

Jet neb running continuously with a simple reservoir is most common.

Others: Continuous w/ collection reservoir -30-50% dose increase

Breath enhanced nebulizers (50% increase)

Breath actuated nebulizers -AeroEclipse

Other Delivery Systems

LVN - continuous delivery (HEART/HOPE Nebs)

Small particle Aerosol Generator (SPAG) ONLY for Ribavirin (Virazole) - antiviral for lower respiratory tract

Ultrasonic - high output, little deadspace, no dilution needed

Vibrating Mesh Neb - Used in ICU and children

ONE TYPE: Aerogen - REQUIRES ELECTRICITY, NOT GAS SOURCE

What are Adrenergic Bronchodilators(Beta Adrenergic Agents, Sympathomimetics)

The most widely prescribed bronchodilators

Relieve airflow obstruction in Asthma, bronchitis, emphysema, bronchiectasis and CF

Two categories (National Asthma Education and Prevention Program Guidelines):

Rescue Agents - short acting for acute obstruction

Controller Agents - long acting maintenance and relief of nocturnal symptoms

Racemic Epinephrine- Poor bronchodilator (used for alpha effects, vasoconstriction)

Side effects: Tachycardia, palpitations, hypertension, restlessness, fear and anxiety, tremors, dizziness, tolerance

Albuterol ; Levalbuterol Salmeterol ; Formoterol

Sympathomimetics are drugs that mimic the effects of the sympathetic nervous system, specifically epinephrine (adrenaline) and norepinephrine.
→ Their main action in respiratory care: relax bronchial smooth muscle to relieve bronchospasm.

Rescues/Controllers

Rescurers most given in hospital;

albuterol -B2, safe/effective

Xopanex - B2, expensive

Controllers - most for maintenance, MDI’s, DPI’s

Anticholinergic Bronchodilators

Maintenance of COPD, as effective as an adrenergic bronchodilator, less effective for asthma

Examples: 

Ipratropium Bromide (Atrovent)

tiotropium Bromide (Spiriva)

Also in combo with Albuterol (Duoneb (SVN)/Combivent (MDI)

Corticosteroids

Are all Controllers - RINSE MOUTH AFTER

Relieve airway inflammation, minimal side effects - full effect hours to days

Example: Fluticasone Propionate (Flovent), Budesonide (Pulmicort)

Mucoytics

For mucous plugging or retained secretions

Mucomyst( potential bronchospasm, give with or after bronchodilator

Hypertonic Saline, sputum induction, irritating to airway, may need bronchodilator

How to Decide?

Form of drug available

Does patient have acute airway obstruction(COPD/Asthma)? SVN is needed

Stable patients on maintenance drugs can do MDI/DPI (not available in nebulizer solution

Patient education is key

How to Assess patients receiving aerosolized medications

-Date and time

-Before, during and after HR, before and after RR and breath sounds

-Peak Flow

-Dose of med, amount of dilutent, mode of therapy, patient position during treatment

-Any adverse effects

-Cough and Sputum Production

-Did patient improve, stay the same, or get worse?

Any complaints regarding the therapy