chapter 16 bronchodilators and other respiratory agents

Chapter 16

Bronchodilators and Other Respiratory Agents

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.

16 - 2

Bronchodilators

Medications used to relax and open the airways

Open or maintain the bronchial airways Treat several disease syndromes

Chronic obstructive pulmonary disease Asthma


16 - 3

Classes of Bronchodilators

Sympathomimetic agents Xanthine bronchodilators Anticholinergics Leukotriene receptor antagonists 5-lipoxygenase inhibitors Mast cell stabilizers Corticosteroids


16 - 4

Sympathomimetics

Beta2-adrenergic receptors Used during the acute phase of asthmatic

attacks Quickly reduce airway constriction and

restore normal airflow


16 - 5

Uses for Sympathomimetics

Treat acute attacks as well as prevent attacks

Quickly reduce airway constriction and restore normal airflow

Relief of bronchospasm, bronchial asthma, bronchitis, and other pulmonary diseases

Treat hypotension and shock Produce uterine relaxation to prevent

premature labor


16 - 6

Sympathomimetic Agents

Nonselective adrenergics Stimulate alpha1, beta1 (cardiac), and

beta2 (respiratory) receptors

Example: epinephrine

(continues)


16 - 7


Nonselective beta-adrenergics Stimulate both beta1 and beta2 receptors

Example: isoproterenol (Isuprel)

Selective beta2 drugs Stimulate only beta2 receptors

Example: albuterol

(continues)

(continued)


16 - 8


Frequent use leads to beta1 receptors being stimulated

Albuterol loses its action General side effects

Nausea, increased anxiety, palpitations, tremors, and increased heart rate

(continued)


16 - 9

Xanthines

Chemical class of agents Contain caffeine

Oldest class of bronchodilators Used in ancient times


16 - 10

Xanthine Bronchodilators: Mechanism of Action

Increase levels of energy-producing cAMP

Inhibit phosphodiesterase Enzyme that breaks down cAMP

Result Smooth muscle relaxation Bronchodilation Increase airflow (oxygen/carbon dioxide) in

the lungs Cause cardiac life-threatening side effects


16 - 11

Xanthine Derivatives: Side Effects

Nausea, vomiting, anorexia Gastroesophageal reflux during sleep Sinus tachycardia, extrasystole,

palpitations, ventricular dysrhythmias Transient increased urination


16 - 12

Anticholinergics: Mechanism of Action

Acetylcholine (ACh) causes bronchial constriction.

Anticholinergics bind to the ACh receptors, preventing ACh from binding.

Result: bronchoconstriction is prevented, airways dilate


16 - 13

Anticholinergic Bronchodilators

Ipratropium bromide (Atrovent) Tiotropium bromide (Spiriva HandiHaler) Actions

Local effects Slow and prolonged action Used to prevent bronchoconstriction Not used for acute asthma exacerbations!


16 - 14

Anticholinergics: Side Effects

Usually not absorbed systemically If absorbed, have the potential to

produce: Dry mouth or dry throat Gastrointestinal distress Headache Coughing Anxiety


16 - 15

Leukotriene Receptor Antagonists

Directly prevent bronchoconstriction Developed to treat asthma Popular and effective Leukotrienes are inflammatory molecules

Released by mast cells Cause the bronchials to contract Development of edema in the lungs

(continues)


16 - 16


By blocking leukotrienes: Prevent smooth muscle contraction of the

bronchial airways Decrease mucus secretion Prevent vascular permeability Decrease neutrophil and leukocyte

infiltration to the lungs

(continues)

(continued)


16 - 17


Currently available agents: Montelukast (Singulair) Zafirlukast (Accolate)

(continued)


16 - 18

Leukotriene Receptor Antagonists: Side Effects

Headache Nausea Diarrhea Liver dysfunction


16 - 19

Leukotriene Receptor Antagonists: Client

Education Educate the client.

Use for chronic management of asthma, not acute asthma

Improvement should be seen in about 1 week


16 - 20

5-Lipoxygenase Inhibitors

New class of leukotriene receptor antagonists

Action Inhibit the formation of leukotrienes Used to inhibit some cancer growth

Outcome Prevent lung inflammation

Example One agent: Zileuton


16 - 21

Mast Cell Stabilizers

Used prophylactically No direct bronchodilator activity Indirect-acting Stabilize the cell membranes of the

inflammatory cells–mast cells, monocytes, macrophages

Prevent release of harmful cellular contents

(continues)


16 - 22

Mast Cell Stabilizers

Adjuncts to the overall management of clients with lung disease

Prevent bronchospasm when exposed to: Cold air Exercise Allergens Dry air

(continued)


16 - 23

Mast Cell Stabilizers: Examples

Cromolyn (Nasalcrom, Intal) Nedocromil (Tilade)


16 - 24

Mast Cell Stabilizers: Side Effects

Coughing Taste changes Sore throat Dizziness Rhinitis Headache Bronchospasm


16 - 25

Inhaled Corticosteroids

Anti-inflammatory Inhaled forms

Reduce systemic effects Used for chronic asthma

Does not relieve acute asthma

(continues)


16 - 26

Inhaled Corticosteroids

Stabilize membranes of cells that release harmful bronchoconstricting substances

Also increase responsiveness of bronchial smooth muscle to beta-adrenergic stimulation

(continued)


16 - 27

Inhaled Corticosteroids: Examples

Beclomethasone dipropionate (Beclovent, Vanceril)

Triamcinolone acetonide (Azmacort)

Flunisolide (AeroBid)


16 - 28

Inhaled Corticosteroids: Side Effects

Pharyngeal irritation Coughing Dry mouth Oral fungal infections Systemic effects are rare


16 - 29

Respiratory Agents

Combination product Fluticasone propionate and salmeterol

(Advair): a dry powder in a circular diskus Salmeterol: long-acting bronchodilator Corticosteroid: anti-inflammatory agent

Used daily


16 - 30

Respiratory Agents: Client Education

Instruct clients to: Receive flu and pneumonia vaccination Receive prompt treatment for any illness Check with health care provider before

taking other medications

chapter 16 bronchodilators and other respiratory agents

Documents

thomson delmar learning

division of thomson

effects slide

continued slide

normal airflow slide

premature labor slide

sympathomimetics beta

respiratory agents