Module 7: Airway Pharmacology Flashcards
Albuterol Sulfate
Proventil
Ventolin
ProAir
AccuNeb
Vospire
The course of drug action from dose to effect comprises three phrases:
Drug administration phase
Pharmacokinetic phase
Pharmacodynamic phase
Drug Administration Phase
Method by which drug is made available to body
Most common devices used to administer inhaled aerosols are:
Metered-Dose Inhaler (MDI)
Soft-Mist Inhaler (Respimat)
Small-Volume Nebulizer (SVN)
Dry-powder Inhaler (DPI)
Advantages of Inhaled Aerosols
Aerosol doses are usually smaller than doses for systemic administration
Onset of drug action is rapid (immediate onset)
Delivery is targeted to the organ requiring treatment
Systemic side effects are often fewer and less severe
Most drugs can be self-administered by the patient
Disadvantages of Inhaled Aerosols
The number of variables affecting the delivered dose
Lack of adequate knowledge of device performance
Use among patients and caregivers
Pharmacokinetic Phase
Describes time course and disposition of drug in body based on its absorption, distribution, metabolism, and elimination
Pharmacodynamic Phase
Describes the 3 mechanisms of drug action by which a drug molecule causes its effects in the body through drug receptor site interactions
Sympathetic (adrenergic) receptor stimulation
Uses norepinephrine as a neurotransmitter, similar to epinephrine
Stimulation causes bronchodilation in the lungs 🫁
Parasympathetic (cholinergic) receptor stimulation
Uses Acetylcholine as a neurotransmitter
Stimulation causes bronchoconstriction in the lungs
Agonists (stimulating agent)
EX: Benadryl (anti-histamine)
A chemical that binds to a receptor site (has affinity) and blocks another chemical from activation which causes no response (no efficacy)
Adrenergic
Drug that stimulates a receptor responding to norepinephrine or epinephrine
What causes bronchodilation of the smooth muscle of the lungs?
Stimulation of the beta-2 adrenergic receptor site causes bronchodilation of the smooth muscle of the lungs
Stimulation of the muscarinic-3 cholinergic receptor site causes?
Bronchoconstriction of the smooth muscle of the lungs
Anti-cholinergic
Drug that blocks a receptor for acetylcholine
Adrenergic Bronchodilators
This class of drug is compromised of the largest single group of drugs amount aerosolized agents used for inhalation
Indications for use
Short-acting beta-2 agonists (SABA)
Short-acting beta-2 agonists (SABA)
Treatment of acute reversible airflow obstruction
Improve flow rates for asthma, acute, and chronic bronchitis, emphysema, bronchiectasis, cystic fibrosis, and other obstructive airways states
The National Asthma Education and Prevention Programs considers SABAs as rescue bronchodilators
Long Acting Beta-2 Agonists (LABA)
For maintenance bronchodilation in patients with obstructive lung disease, commonly referred to as control drugs
Ultra Short Acting Agents
Ultra Short Acting Agents catecholamine (strong alpha 1) resulting in vasoconstriction of the bronchial blood vessels
To reduce airway swelling after extubation, during croup, or epiglottitis
To control airway bleeding during endoscopy
What are the mechanisms and effects of Adrenergic Bronchodilators?
Alpha-receptor stimulation: causes vasoconstriction and vasopressin effect
Beta-1 receptor stimulation: causes increased heart rate and heart contractility
Beta-2 receptor stimulation: relaxes bronchial smooth muscle, stimulates mucociliary activity, and has some inhibitory action on inflammatory mediator release
Most common adverse effects of adrenergic bronchodilators?
Tremors
Headache
Nervousness
Insomnia
Hypokalemia
What are the side effects seen with anticholinergic aerosol agents?
SVN, MDI, and DPI (COMMON)
-Cough, dry mouth
What is the assessment for anticholinergic bronchodilators?
Vital signs, breath sounds, and breathing pattern should be evaluated before and after treatment
Patient’s subjective response is important to evaluate
How is N-Acetyl-L-Cysteine (NAC) a.k.a (Mucomyst) delivered?
Given by aerosol or direct tracheal instillation
What are the indications for N-Acetyl-L-Cysteine (NAC) a.k.a Mucomyst?
Acute bronchitis, bronchiectasis, COPD, and also acetaminophen overdose