bronchodilators

Copyright © 2002, 1998, Elsevier Science (USA). All rights reserved.

Bronchodilators and Other Bronchodilators and Other Respiratory AgentsRespiratory Agents


Drugs Affecting Drugs Affecting the Respiratory Systemthe Respiratory System

• BronchodilatorsBronchodilators

– Xanthine derivativesXanthine derivatives

– Beta-agonistsBeta-agonists

• AnticholinergicsAnticholinergics

• Antileukotriene agentsAntileukotriene agents

• CorticosteroidsCorticosteroids

• Mast cell stabilizersMast cell stabilizers


Instructors may want to use Instructors may want to use EIC Image #94: EIC Image #94:

Airway Restrictive FactorsAirway Restrictive Factors


Bronchodilators: Xanthine DerivativesBronchodilators: Xanthine Derivatives

• Plant alkaloids: caffeine, theobromine, and Plant alkaloids: caffeine, theobromine, and theophyllinetheophylline

• Only theophylline is used as a bronchodilatorOnly theophylline is used as a bronchodilator

Examples:Examples: aminophyllineaminophyllinedyphilline dyphilline oxtriphyllineoxtriphyllinetheophylline (Bronkodyl, Slo-theophylline (Bronkodyl, Slo-

bid,bid,Theo-Dur,Uniphyl)Theo-Dur,Uniphyl)


Bronchodilators: Xanthine Derivatives Bronchodilators: Xanthine Derivatives Mechanism of ActionMechanism of Action

• Increase levels of energy-producing cAMP*Increase levels of energy-producing cAMP*

• This is done competitively inhibiting This is done competitively inhibiting phosphodiesterase (PDE), the enzyme that phosphodiesterase (PDE), the enzyme that breaks down cAMPbreaks down cAMP

• Result: decreased cAMP levels, smooth Result: decreased cAMP levels, smooth muscle relaxation, bronchodilation, and muscle relaxation, bronchodilation, and increased airflowincreased airflow

*cAMP = cyclic adenosine monophosphate*cAMP = cyclic adenosine monophosphate


Bronchodilators: Xanthine Derivatives Bronchodilators: Xanthine Derivatives Drug EffectsDrug Effects

• Cause bronchodilation by relaxing smooth muscles Cause bronchodilation by relaxing smooth muscles of the airways.of the airways.

• Result: relief of bronchospasm and greater airflow Result: relief of bronchospasm and greater airflow into and out of the lungs.into and out of the lungs.

• Also causes CNS stimulation.Also causes CNS stimulation.

• Also causes cardiovascular stimulation: increased Also causes cardiovascular stimulation: increased force of contraction and increased HR, resulting in force of contraction and increased HR, resulting in increased cardiac output and increased blood flow to increased cardiac output and increased blood flow to the kidneys (diuretic effect).the kidneys (diuretic effect).


Bronchodilators: Xanthine Derivatives Bronchodilators: Xanthine Derivatives Therapeutic UsesTherapeutic Uses

• Dilation of airways in asthmas, chronic Dilation of airways in asthmas, chronic bronchitis, and emphysemabronchitis, and emphysema

• Mild to moderate cases of asthmaMild to moderate cases of asthma

• Adjunct agent in the management of COPDAdjunct agent in the management of COPD

• Adjunct therapy for the relief of pulmonary Adjunct therapy for the relief of pulmonary edema and paroxysmal nocturnal edema in edema and paroxysmal nocturnal edema in left-sided heart failureleft-sided heart failure


Bronchodilators: Xanthine Derivatives Bronchodilators: Xanthine Derivatives Side EffectsSide Effects

• Nausea, vomiting, anorexiaNausea, vomiting, anorexia

• Gastroesophageal reflux during sleepGastroesophageal reflux during sleep

• Sinus tachycardia, extrasystole, palpitations, Sinus tachycardia, extrasystole, palpitations, ventricular dysrhythmiasventricular dysrhythmias

• Transient increased urinationTransient increased urination


Bronchodilators: Beta-AgonistsBronchodilators: Beta-Agonists

• Large group, sympathomimeticsLarge group, sympathomimetics

• Used during acute phase of asthmatic Used during acute phase of asthmatic attacksattacks

• Quickly reduce airway constriction and Quickly reduce airway constriction and restore normal airflowrestore normal airflow

• Stimulate betaStimulate beta22 adrenergic receptors adrenergic receptors throughout the lungsthroughout the lungs


Bronchodilators: Beta-Agonists Bronchodilators: Beta-Agonists Three typesThree types

• Nonselective adrenergicsNonselective adrenergics

– Stimulate alphaStimulate alpha11, beta, beta11 (cardiac), and beta (cardiac), and beta22 (respiratory) (respiratory) receptors.receptors.

Example: epinephrineExample: epinephrine

• Nonselective beta-adrenergicsNonselective beta-adrenergics

– Stimulate both betaStimulate both beta11 and beta and beta22 receptors. receptors.

Example: isoproterenol (Isuprel)Example: isoproterenol (Isuprel)

• Selective betaSelective beta22 drugs drugs

– Stimulate only betaStimulate only beta22 receptors. receptors.

Example: albuterolExample: albuterol


Bronchodilators: Beta-Agonists Bronchodilators: Beta-Agonists Mechanism of ActionMechanism of Action

• Begins at the specific receptor stimulatedBegins at the specific receptor stimulated

• Ends with the dilation of the airwaysEnds with the dilation of the airways

Activation of betaActivation of beta22 receptors activate cAMP, which receptors activate cAMP, which relaxes smooth muscles of the airway and results relaxes smooth muscles of the airway and results in bronchial dilation and increased airflow.in bronchial dilation and increased airflow.


Bronchodilators: Beta-Agonists Bronchodilators: Beta-Agonists Therapeutic UsesTherapeutic Uses

• Relief of bronchospasm, bronchial asthma, Relief of bronchospasm, bronchial asthma, bronchitis, and other pulmonary disease.bronchitis, and other pulmonary disease.

• Useful in treatment of acute attacks as well Useful in treatment of acute attacks as well as prevention.as prevention.

• Used in hypotension and shock.Used in hypotension and shock.

• Used to produce uterine relaxation to prevent Used to produce uterine relaxation to prevent premature labor.premature labor.

• Hyperkalemia—stimulates potassium to shift Hyperkalemia—stimulates potassium to shift into the cell.into the cell.


Bronchodilators: Beta-Agonists Bronchodilators: Beta-Agonists Side EffectsSide Effects

Alpha-Beta Alpha-Beta BetaBeta11 and Beta and Beta22 BetaBeta22

(epinephrine)(epinephrine) (isoproterenol)(isoproterenol) (albuterol)(albuterol)

insomniainsomnia cardiac stimulationcardiac stimulation hypotensionhypotensionrestlessnessrestlessness tremortremor vascularvascular

headacheheadacheanorexiaanorexia anginal painanginal pain tremortremorcardiac stimulationcardiac stimulation vascular headachevascular headache tremortremorvascular headachevascular headache


Respiratory Agents: Respiratory Agents: General Nursing ImplicationsGeneral Nursing Implications

• Encourage patients to take measures that Encourage patients to take measures that promote a generally good state of health in promote a generally good state of health in order to prevent, relieve, or decrease order to prevent, relieve, or decrease symptoms of COPD.symptoms of COPD.

– Avoid exposure to conditions that precipitate Avoid exposure to conditions that precipitate bronchospasms (allergens, smoking, stress, air pollutants)bronchospasms (allergens, smoking, stress, air pollutants)

– Adequate fluid intakeAdequate fluid intake

– Compliance with medical treatmentCompliance with medical treatment

– Avoid excessive fatigue, heat, extremes in temperature, Avoid excessive fatigue, heat, extremes in temperature, caffeinecaffeine



• Encourage patients to get prompt treatment Encourage patients to get prompt treatment for flu or other illnesses, and to get for flu or other illnesses, and to get vaccinated against pneumonia or flu.vaccinated against pneumonia or flu.

• Encourage patients to always check with Encourage patients to always check with their physician before taking any other their physician before taking any other medication, including OTC.medication, including OTC.



• Perform a thorough assessment before Perform a thorough assessment before beginning therapy, including:beginning therapy, including:– Skin colorSkin color– Baseline vital signsBaseline vital signs– Respirations (should be <12 or >24 breaths/min)Respirations (should be <12 or >24 breaths/min)– Respiratory assessment, including PORespiratory assessment, including PO22

– Sputum productionSputum production– AllergiesAllergies– History of respiratory problemsHistory of respiratory problems– Other medications Other medications



• Teach patients to take bronchodilators Teach patients to take bronchodilators exactly as prescribed.exactly as prescribed.

• Ensure that patients know how to use Ensure that patients know how to use inhalers, MDIs, and have the patients inhalers, MDIs, and have the patients demonstrate use of devices.demonstrate use of devices.

• Monitor for side effects.Monitor for side effects.


Respiratory Agents: Respiratory Agents: Nursing ImplicationsNursing Implications

• Monitor for therapeutic effectsMonitor for therapeutic effects

– Decreased dyspneaDecreased dyspnea

– Decreased wheezing, restlessness, and anxietyDecreased wheezing, restlessness, and anxiety

– Improved respiratory patterns with return to Improved respiratory patterns with return to normal rate and qualitynormal rate and quality

– Improved activity toleranceImproved activity tolerance

• Decreased symptoms and increased Decreased symptoms and increased ease of breathingease of breathing


Bronchodilators: Nursing Implications Bronchodilators: Nursing Implications Xanthine DerivativesXanthine Derivatives

• Contraindications: history of PUD or Contraindications: history of PUD or GI disordersGI disorders

• Cautious use: cardiac diseaseCautious use: cardiac disease

• Timed-release preparations should not be Timed-release preparations should not be crushed or chewed (causes gastric irritation)crushed or chewed (causes gastric irritation)



• Report to physician:Report to physician:

PalpitationsPalpitations NauseaNausea VomitingVomiting

WeaknessWeakness DizzinessDizziness Chest painChest pain

ConvulsionsConvulsions



• Be aware of drug interactions with:Be aware of drug interactions with:cimetidine, oral contraceptives, allopurinolcimetidine, oral contraceptives, allopurinol

• Large amounts of caffeine can have Large amounts of caffeine can have deleterious effects.deleterious effects.


Bronchodilators: Nursing Implications Bronchodilators: Nursing Implications Beta-Agonist DerivativesBeta-Agonist Derivatives

• Albuterol, if used too frequently, loses its Albuterol, if used too frequently, loses its betabeta22-specific actions at larger doses.-specific actions at larger doses.

• As a result, betaAs a result, beta11 receptors are stimulated, receptors are stimulated, causing nausea, increased anxiety, causing nausea, increased anxiety, palpitations, tremors, and increased palpitations, tremors, and increased heart rate.heart rate.


Bronchodilators: Nursing ImplicationsBronchodilators: Nursing ImplicationsBeta-Agonist DerivativesBeta-Agonist Derivatives

• Patients should take medications exactly Patients should take medications exactly as prescribed, with no omissions or double as prescribed, with no omissions or double doses.doses.

• Patients should report insomnia, jitteriness, Patients should report insomnia, jitteriness, restlessness, palpitations, chest pain, or restlessness, palpitations, chest pain, or any change in symptoms.any change in symptoms.


Anticholinergics: Anticholinergics: Mechanism of ActionMechanism of Action

• Acetylcholine (ACh) causes bronchial Acetylcholine (ACh) causes bronchial constriction and narrowing of the airways.constriction and narrowing of the airways.

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

• Result: bronchoconstriction is prevented, Result: bronchoconstriction is prevented, airways dilate.airways dilate.


AnticholinergicsAnticholinergics

• Ipratropium bromide (Atrovent) is the only Ipratropium bromide (Atrovent) is the only anticholinergic used for respiratory disease.anticholinergic used for respiratory disease.

• Slow and prolonged actionSlow and prolonged action

• Used to Used to preventprevent bronchoconstriction bronchoconstriction

• NOT used for acute asthma exacerbations!NOT used for acute asthma exacerbations!


Anticholinergics: Side EffectsAnticholinergics: Side Effects

Dry mouth or throatDry mouth or throat Gastrointestinal Gastrointestinal distressdistress

HeadacheHeadache CoughingCoughing

AnxietyAnxiety

No known drug interactionsNo known drug interactions


AntileukotrienesAntileukotrienes

• Also called leukotriene receptor antagonists Also called leukotriene receptor antagonists (LRTAs)(LRTAs)

• New class of asthma medicationsNew class of asthma medications

• Three subcategories of agentsThree subcategories of agents


AntileukotrienesAntileukotrienes

Currently available agents:Currently available agents:

• montelukast (Singulair)montelukast (Singulair)

• zafirlukast (Accolate)zafirlukast (Accolate)

• zileuton (Zyflo)zileuton (Zyflo)


Antileukotrienes: Antileukotrienes: Mechanism of ActionMechanism of Action

• Leukotrienes are substances released when Leukotrienes are substances released when a trigger, such as cat hair or dust, starts a a trigger, such as cat hair or dust, starts a series of chemical reactions in the body.series of chemical reactions in the body.

• Leukotrienes cause inflammation, Leukotrienes cause inflammation, bronchoconstriction, and mucus production.bronchoconstriction, and mucus production.

• Result: coughing, wheezing, shortnessResult: coughing, wheezing, shortnessof breathof breath


Antileukotrienes: Antileukotrienes: Mechanism of ActionMechanism of Action

• Antileukotriene agents Antileukotriene agents preventprevent leukotrienes leukotrienes from attaching to receptors on cells in the from attaching to receptors on cells in the lungs and in circulation.lungs and in circulation.

• Inflammation in the lungs is Inflammation in the lungs is blockedblocked, and , and asthma symptoms are relieved.asthma symptoms are relieved.


Antileukotrienes: Drug EffectsAntileukotrienes: Drug Effects

By blocking leukotrienes:By blocking leukotrienes:

• Prevent smooth muscle contraction of the Prevent smooth muscle contraction of the bronchial airwaysbronchial airways

• Decrease mucus secretionDecrease mucus secretion

• Prevent vascular permeabilityPrevent vascular permeability

• Decrease neutrophil and leukocyte infiltration Decrease neutrophil and leukocyte infiltration to the lungs, preventing inflammationto the lungs, preventing inflammation


Antileukotrienes: Therapeutic UsesAntileukotrienes: Therapeutic Uses

• Prophylaxis and chronic treatment of asthma Prophylaxis and chronic treatment of asthma in adults and children over age 12in adults and children over age 12

• NOT meant for management of acute NOT meant for management of acute asthmatic attacksasthmatic attacks

• Montelukast is approved for use in children Montelukast is approved for use in children age 2 and olderage 2 and older


Antileukotrienes: Side EffectsAntileukotrienes: Side Effects

zileutonzileuton zafirlukastzafirlukast

HeadacheHeadache HeadacheHeadache

DyspepsiaDyspepsia NauseaNausea

NauseaNausea DiarrheaDiarrhea

DizzinessDizziness Liver dysfunctionLiver dysfunction

InsomniaInsomnia

Liver dysfunctionLiver dysfunction

montelukast has fewer side effects montelukast has fewer side effects


Antileukotrienes: Antileukotrienes: Nursing ImplicationsNursing Implications

• Ensure that the drug is being used for Ensure that the drug is being used for chronic management of asthma, not chronic management of asthma, not acute asthma.acute asthma.

• Teach the patient the purpose of the therapy.Teach the patient the purpose of the therapy.

• Improvement should be seen in about Improvement should be seen in about 1 week.1 week.


Antileukotrienes: Antileukotrienes: Nursing ImplicationsNursing Implications

• Check with physician before taking any Check with physician before taking any OTC or prescribed medications—many OTC or prescribed medications—many drug interactions.drug interactions.

• Assess liver function before beginning Assess liver function before beginning therapy.therapy.

• Medications should be taken every night on Medications should be taken every night on a continuous schedule, even if symptoms a continuous schedule, even if symptoms improve.improve.


CorticosteroidsCorticosteroids

• Anti-inflammatoryAnti-inflammatory

• Used for CHRONIC asthmaUsed for CHRONIC asthma

• Do not relieve symptoms of acute Do not relieve symptoms of acute asthmatic attacksasthmatic attacks

• Oral or inhaled formsOral or inhaled forms

• Inhaled forms reduce systemic effectsInhaled forms reduce systemic effects

• May take several weeks before full May take several weeks before full effects are seeneffects are seen


Corticosteroids: Corticosteroids: Mechanism of ActionMechanism of Action

• Stabilize membranes of cells that release Stabilize membranes of cells that release harmful bronchoconstricting substances.harmful bronchoconstricting substances.

• These cells are leukocytes, or white These cells are leukocytes, or white blood cells.blood cells.

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


Inhaled CorticosteroidsInhaled Corticosteroids

• beclomethasone dipropionate beclomethasone dipropionate (Beclovent, Vanceril)(Beclovent, Vanceril)

• triamcinolone acetonide triamcinolone acetonide (Azmacort)(Azmacort)

• dexamethasone sodium phosphate dexamethasone sodium phosphate (Decadron Phosphate Respihaler)(Decadron Phosphate Respihaler)

• flunisolide (AeroBid)flunisolide (AeroBid)


Inhaled Corticosteroids: Inhaled Corticosteroids: Therapeutic UsesTherapeutic Uses

• Treatment of bronchospastic disorders Treatment of bronchospastic disorders that are not controlled by conventional that are not controlled by conventional bronchodilators.bronchodilators.

• NOT considered first-line agents for NOT considered first-line agents for management of acute asthmatic attacks management of acute asthmatic attacks or status asthmaticus.or status asthmaticus.


Inhaled Corticosteroids: Inhaled Corticosteroids: Side EffectsSide Effects

• Pharyngeal irritationPharyngeal irritation

• CoughingCoughing

• Dry mouthDry mouth

• Oral fungal infectionsOral fungal infections

Systemic effects are rare because of the low Systemic effects are rare because of the low doses used for inhalation therapy.doses used for inhalation therapy.


Inhaled Corticosteroids: Inhaled Corticosteroids: Nursing ImplicationsNursing Implications

• Contraindicated in patients with psychosis, Contraindicated in patients with psychosis, fungal infections, AIDS, TB.fungal infections, AIDS, TB.

• Cautious use in patients with diabetes, Cautious use in patients with diabetes, glaucoma, osteoporosis, PUD, renal glaucoma, osteoporosis, PUD, renal disease, CHF, edema.disease, CHF, edema.

• Teach patients to gargle and rinse the mouth Teach patients to gargle and rinse the mouth with water afterward to prevent the with water afterward to prevent the development of oral fungal infections.development of oral fungal infections.


Inhaled Corticosteroids: Inhaled Corticosteroids: Nursing ImplicationsNursing Implications

• Abruptly discontinuing these medications Abruptly discontinuing these medications can lead to serious problems.can lead to serious problems.

• If discontinuing, should be weaned for a If discontinuing, should be weaned for a period of 1 to 2 weeks, and only if period of 1 to 2 weeks, and only if recommended by physician.recommended by physician.

• REPORT any weight gain of more than 5 REPORT any weight gain of more than 5 pounds a week or the occurrence of chest pounds a week or the occurrence of chest pain.pain.


Mast Cell StabilizersMast Cell Stabilizers

• cromolyn (Nasalcrom, Intal)cromolyn (Nasalcrom, Intal)

• nedocromil (Tilade)nedocromil (Tilade)


Mast Cell StabilizersMast Cell Stabilizers

• Indirect-acting agents that prevent the Indirect-acting agents that prevent the release of the various substances that release of the various substances that cause bronchospasmcause bronchospasm

• Stabilize the cell membranes of Stabilize the cell membranes of inflammatory cells (mast cells, monocytes, inflammatory cells (mast cells, monocytes, macrophages), thus preventing release of macrophages), thus preventing release of harmful cellular contentsharmful cellular contents

• No direct bronchodilator activityNo direct bronchodilator activity

• Used prophylacticallyUsed prophylactically


Mast Cell Stabilizers: Mast Cell Stabilizers: Therapeutic UsesTherapeutic Uses

• Adjuncts to the overall management Adjuncts to the overall management of COPDof COPD

• Used solely for prophylaxis, NOT for Used solely for prophylaxis, NOT for acute asthma attacksacute asthma attacks

• Used to prevent exercise-induced Used to prevent exercise-induced bronchospasmbronchospasm

• Used to prevent bronchospasm associated Used to prevent bronchospasm associated with exposure to known precipitating factors, with exposure to known precipitating factors, such as cold, dry air or allergenssuch as cold, dry air or allergens


Mast Cell Stabilizers: Side EffectsMast Cell Stabilizers: Side Effects

CoughingCoughing Taste changesTaste changes

Sore throatSore throat DizzinessDizziness

RhinitisRhinitis HeadacheHeadache

BronchospasmBronchospasm


Mast Cell Stabilizers: Mast Cell Stabilizers: Nursing ImplicationsNursing Implications

• For prophylactic use onlyFor prophylactic use only

• Contraindicated for acute exacerbationsContraindicated for acute exacerbations

• Not recommended for children under age 5Not recommended for children under age 5

• Therapeutic effects may not be seen for up Therapeutic effects may not be seen for up to 4 weeksto 4 weeks

• Teach patients to gargle and rinse the mouth Teach patients to gargle and rinse the mouth with water afterward to minimize irritation to with water afterward to minimize irritation to the throat and oral mucosathe throat and oral mucosa

bronchodilators

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