Transcript Respiratory Drugs Part 1

Bronchodilators
Lilley Pharmacology Text: Chapter 35
Original PPT modified by:
Anita A. Kovalsky, R.N., M.N.Ed.
Professor of Nursing
Original by: Professor Edwards,
Review of Glossary Terms:
Lilley pg. 542
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Alveoli:
Antigen:
Antibody:
Asthma Attack:
Bronchial Asthma:
Chronic Bronchitis:
Emphysema:
ADDITIONAL TERMS
• Acute:
• Exacerbation:
Diseases commonly treated with
Bronchodilators
• Asthma
http://www.whatsasthma.org
COPD
Chronic Bronchitis
Emphysema
BRONCHODILATOR
CLASSIFICATIONS
Bronchodilators:
1)
Xanthines Derivatives
2)
Beta-Agonists
Xanthine Derivatives
(Refer to Prototype List in syllabus, pg. 19)
• Prototype Drugs:
– Theophylline- Theo-dur
– Aminophylline
How Do These Drugs Work?
• Relieve Bronchoconstriction
• Cause bronchodilatation
Mechanism of Action
• Cause bronchodilation by:
– Increasing the levels of the energy
producing substance called cAMP
– Inhibiting PDE the enzyme that breaks
down *cAMP….
– Subsequently, this causes smooth muscle
relaxation and broncchodilation; also
inhibits release of chemical mediators
such as histamine, etc.
– *cAMP = cyclic adenosine monophosphate
Mechanism of Action contd.
• Slow onset of action, so used more as
preventative measure, however, also
used as a continuous IV infusion to
treat reversible bronchospasm in COPD
clients who have an exacerbation of
symptoms
Drug Effects
• Relieve bronchopasms
by causing airways to
dilate, thereby
improving air passage
into and out of lungs
• Stimulates CNS:
– Increases contractility of
heart (+ inotropic)
– Increases heart rate
(+chrontropic)
– Increases cardiac output,
thereby causing a….
– Diuretic effect…what
would cause
this???????
Therapeutic Uses
• Dilate airways in
asthma, chronic
bronchitis and
emphysema
• Adjunctive agent for
treatment of pulmonary
edema and dyspnea in
left-sided heart failure
by increasing cardiac
output and increasing
bloodflow to kidneys
diuresis
Lab Diagnostics
Cavanaugh Text: pg. 215
Aminophylline/Theophylline Levels:
–10-18ug/ml WNL (within normal limits)
–>20ug/ml TOXIC LEVEL
Side and Adverse Effects
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Nausea
Vomiting
Anorexia
Gastroesophageal reflux
CARDIAC!!!!!!!! HIGH ALERT!!!!
• Sinus Tachycardia
• Palpitations
• Ventricular Dysrhythmias
• Hyperglycemia (transient)
• Increased urinary output (transient)
Interactions
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Allopurinol
Cimetidine
Erythromycin
Flu Vaccine
Oral Contraceptives
• Need blood levels
monitored closely
Available Theophylline
Preparations
–Oral
–Parenteral
(aminophylline infusion)
–Rectal
Beta-Agonists or Sympathomimetic
Bronchodilators
(Refer to Prototype List in syllabus, pg. 19
Also listed in Lilley, pg. 548)
• Prototype Drugs: (Brand name
in parentheses)
- Albuterol (Proventil)
Beta2 Selective
OTHERS:
-Ephedrine
-Epinephrine (Adrenalin, Primatene, Bronkaid)
-Terbutaline (Brethine)
When are Beta-Agonists used?
• During acute phase of asthmatic attack
• To quickly reduce airway constriction and cause
bronchodilation
WHY ARE THEY CALLED AGONISTS????
• AGONISTS or stimulators of SNS receptors----->
SYMPATHOMIMETIC ACTION
WHAT IS THE PRIMARY MECHANISM OF ACTION??
• Imitate the effects of norepinephrine on receptors
• Stimulate beta2-adrenergic receptors in the
lungs causing dilation within the airways of
the lungs (Example: Albuterol/Proventil)
Specific Receptors
Refer to Lilley text, pg. 547
• Nonselective adrenergic: stimulate the alpha,
beta1 (cardiac), and beta2- (respiratory)
receptors (Example: epinephrine)
• Nonselective beta-adrenergic: stimulate both
beta1 and beta2 receptors (Example: Isuprel)
• Selective beta2: stimulate the beta2
receptors (Example: albuterol)
Drug Effects
**SELECTIVE BETA2
• Beta2 stimulation causes
bronchodilation; also a decreased
diastolic B/P, decreased K+ level
Mechanism of Action
• Begins with specific receptors
stimulated and ends with the dilation of
airways
• cAMP is activated when a beta2adrenergic receptor is stimulated
• Smooth muscles relax and airflow
increased
Therapeutic Uses of
Beta-Agonists
• Pulmonary
disorders for relief
of bronchospasm
• Nonselective: Used
for hypotension and
shock treatment and
to relieve nasal
congestion and
stuffiness
Bronchodilators: Beta-Agonists
Side Effects
Alpha-Beta
Beta1 and Beta2 Beta2
(epinephrine)
(isoproterenol)
Insomnia
restlessness
anorexia
cardiac stimulation
vascular headache
cardiac stimulation
tremor
anginal pain
vascular headache
(albuterol)
hypotension
vascular headache
tremor
Interactions
• Beta-agonist with
nonselective betaadrenergic blocker (betablocker) antagonizes the
bronchodilation effect!!!
• Avoid MAO inhibitors
Available Selected
Beta-Agonist Preparations
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PO
SC
Inhaler
Nebulizer
IM
Nursing Considerations for
Bronchodilators
• Does the client have cardiac disease??
• If so, which type of bronchodilator
should be the drug of choice??
• Does the client have diabetes??
• If the client is receiving a xanthine,
what blood levels should be
monitored???
A client is receiving IV aminophylline
for a severe exacerbation of COPD.
Which of the following would you
expect when evaluating for a
therapeutic response to the
medication?
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B.
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D.
Drowsiness
Increased heart rate
Dilatation of bronchioles
Increased respiratory rate
Which of the following side
effects is associated with the
use of xanthine derivatives?
A.
B.
C.
D.
Bradycardia
Palpitations
Increase in appetite
Constriction of bronchioles
Overview of Drugs Affecting
the Respiratory System
• Bronchodilators
– Xanthine derivatives
– Beta-agonists
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Anticholinergics
Antileukotriene agents
Corticosteroids
Mast cell stabilizers
THE END