CHAPTER 37 Bronchodilators and Other Respiratory Drugs Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. Diseases of the Lower Respiratory Tract COPD Asthma Emphysema Chronic bronchitis Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 2 Bronchial Asthma Recurrent and reversible shortness of breath Occurs when the airways of the lungs become narrow as a result of: Bronchospasms Inflammation of the bronchial mucosa Edema of the bronchial mucosa Production of viscid mucus Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 3 Bronchial Asthma (cont’d) Alveolar ducts/alveoli remain open, but airflow to them is obstructed Symptoms Wheezing Difficulty breathing Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 4 Asthma Three categories Allergic Idiopathic Mixed allergic-idiopathic Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 5 Asthma (cont’d) Status asthmaticus Prolonged asthma attack that does not respond to typical drug therapy May last several minutes to hours Medical emergency Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 6 Chronic Bronchitis Continuous inflammation of the bronchi and bronchioles Often occurs as a result of prolonged exposure to bronchial irritants Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 7 Emphysema Air spaces enlarge as a result of the destruction of alveolar walls The surface area where gas exchange takes place is reduced Effective respiration is impaired Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 8 Drugs Used to Treat Asthma Long-term control Leukotriene receptor antagonists Inhaled steroids Long-acting beta2-agonists Quick relief Intravenous systemic corticosteroids Short-acting inhaled beta2-agonists Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 9 Bronchodilators and Respiratory Drugs Bronchodilators Beta-adrenergic agonists Xanthine derivatives Anticholinergics Leukotriene receptor antagonists Corticosteroids Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 10 Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 11 Bronchodilators: Beta-Agonists Large group, sympathomimetics Used during acute phase of asthmatic attacks Quickly reduce airway constriction and restore normal airflow Stimulate beta2-adrenergic receptors throughout the lungs Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 12 Bronchodilators: Beta-Agonists (cont’d) Three types Nonselective adrenergics Stimulate alpha, beta1 (cardiac), and beta2 (respiratory) receptors Example: epinephrine Nonselective beta-adrenergics Stimulate both beta1 and beta2 receptors Example: metaproterenol (Alupent) Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 13 Bronchodilators: Beta-Agonists (cont’d) Three types (cont’d) Selective beta2 drugs Stimulate only beta2 receptors Example: albuterol (Proventil, others) Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 14 Beta-Agonists: Mechanism of Action Begins at the specific receptor stimulated Ends with dilation of the airways Activation of beta2 receptors activates cyclic adenosine monophosphate (cAMP), which relaxes smooth muscle in the airway and results in bronchial dilation and increased airflow Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 15 Beta-Agonists: Indications Relief of bronchospasm related to asthma, bronchitis, and other pulmonary diseases Used in treatment and prevention of acute attacks Used in hypotension and shock Used to produce uterine relaxation to prevent premature labor Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 16 Beta-Agonists: Adverse Effects Alpha and beta (epinephrine) Insomnia Restlessness Anorexia Vascular headache Hyperglycemia Tremor Cardiac stimulation Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 17 Beta-Agonists: Adverse Effects (cont’d) Beta1 and beta2 (metaproterenol) Cardiac stimulation Tremor Anginal pain Vascular headache Hypotension Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 18 Beta-Agonists: Adverse Effects (cont’d) Beta2 (albuterol) Hypotension OR hypertension Vascular headache Tremor Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 19 Nursing Implications Encourage patients to take measures that promote a generally good state of health so as to prevent, relieve, or decrease symptoms of COPD Avoid exposure to conditions that precipitate bronchospasm (allergens, smoking, stress, air pollutants) Adequate fluid intake Compliance with medical treatment Avoid excessive fatigue, heat, extremes in temperature, caffeine Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 20 Nursing Implications (cont’d) Encourage patients to get prompt treatment for flu or other illnesses, and to get vaccinated against pneumonia or flu Encourage patients to always check with their physician before taking any other medication, including over-the-counter medications Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 21 Nursing Implications (cont’d) Perform a thorough assessment before beginning therapy, including: Skin color Baseline vital signs Respirations (should be between 12 and 24 breaths/min) Respiratory assessment, including pulse oximetry Sputum production Allergies History of respiratory problems Other medications Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 22 Nursing Implications (cont’d) Teach patients to take bronchodilators exactly as prescribed Ensure that patients know how to use inhalers and MDIs, and have patients demonstrate use of the devices Monitor for adverse effects Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 23 Nursing Implications (cont’d) Monitor for therapeutic effects Decreased dyspnea Decreased wheezing, restlessness, and anxiety Improved respiratory patterns with return to normal rate and quality Improved activity tolerance Decreased symptoms and increased ease of breathing Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 24 Nursing Implications (cont’d) Beta-agonist derivatives Albuterol, if used too frequently, loses its beta2-specific actions at larger doses As a result, beta1 receptors are stimulated, causing nausea, increased anxiety, palpitations, tremors, and increased heart rate Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 25 Nursing Implications (cont’d) Beta-agonist derivatives (cont’d) Ensure that patients take medications exactly as prescribed, with no omissions or double doses Inform patients to report insomnia, jitteriness, restlessness, palpitations, chest pain, or any change in symptoms Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 26 Inhalers: Patient Education For any inhaler prescribed, ensure that the patient is able to self-administer the medication Provide demonstration and return demonstration Ensure that the patient knows the correct time intervals for inhalers Provide a spacer if the patient has difficulty coordinating breathing with inhaler activation Ensure that the patient knows how to keep track of the number of doses in the inhaler device Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 27 Anticholinergics Ipratropium bromide (Atrovent) and tiotropium (Spiriva) Slow and prolonged action Used to prevent bronchoconstriction NOT used for acute asthma exacerbations! Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 28 Anticholinergics: Mechanism of Action Acetylcholine (ACh) causes bronchial constriction and narrowing of the airways Anticholinergics bind to the ACh receptors, preventing ACh from binding Result: bronchoconstriction is prevented, airways dilate Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 29 Anticholinergics: Adverse Effects Dry mouth or throat Nasal congestion Heart palpitations Gastrointestinal distress Headache Coughing Anxiety No known drug interactions Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 30 Bronchodilators: Xanthine Derivatives Plant alkaloids: caffeine, theobromine, and theophylline Only theophylline is used as a bronchodilator Synthetic xanthines: aminophylline and dyphilline Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 31 Xanthine Derivatives: Mechanism of Action Increase levels of energy-producing cAMP This is done competitively inhibiting phosphodiesterase (PDE), the enzyme that breaks down cAMP Result: decreased cAMP levels, smooth muscle relaxation, bronchodilation, and increased airflow Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 32 Xanthine Derivatives: Drug Effects Also cause cardiovascular stimulation: increased force of contraction and increased heart rate, resulting in increased cardiac output and increased blood flow to the kidneys (diuretic effect) Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 33 Xanthine Derivatives: Drug Effects (cont’d) Cause bronchodilation by relaxing smooth muscle in the airways Result: relief of bronchospasm and greater airflow into and out of the lungs Also cause CNS stimulation Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 34 Xanthine Derivatives: Indications Dilation of airways in asthmas, chronic bronchitis, and emphysema Mild to moderate cases of acute asthma Adjunct drug in the management of COPD Not used as frequently because of potential for drug interactions and variables related to drug levels in the blood Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 35 Xanthine Derivatives: Adverse Effects Nausea, vomiting, anorexia Gastroesophageal reflux during sleep Sinus tachycardia, extrasystole, palpitations, ventricular dysrhythmias Transient increased urination Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 36 Xanthine Derivatives: Nursing Implications Contraindications: history of PUD or GI disorders Cautious use: cardiac disease Timed-release preparations should not be crushed or chewed (cause gastric irritation) Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 37 Xanthine Derivatives: Nursing Implications (cont’d) Report to physician: Palpitations Weakness Convulsions Nausea Dizziness Vomiting Chest pain Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 38 Xanthine Derivatives: Nursing Implications (cont’d) Be aware of drug interactions with cimetidine, oral contraceptives, allopurinol, certain antibiotics, others Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 39 Leukotriene Receptor Antagonists (LTRAs) Newer class of asthma medications Currently available drugs montelukast (Singulair) zafirlukast (Accolate) zileuton (Zyflo) Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 40 LRTAs: Mechanism of Action Leukotrienes are substances released when a trigger, such as cat hair or dust, starts a series of chemical reactions in the body Leukotrienes cause inflammation, bronchoconstriction, and mucus production Result: coughing, wheezing, shortness of breath Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 41 LRTAs: Mechanism of Action (cont’d) LRTAs prevent leukotrienes from attaching to receptors on cells in the lungs and in circulation Inflammation in the lungs is blocked, and asthma symptoms are relieved Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 42 LRTAs: Drug Effects 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, preventing inflammation Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 43 LRTAs: Indications Prophylaxis and chronic treatment of asthma in adults and children older than age 12 NOT meant for management of acute asthmatic attacks Montelukast is approved for use in children ages 2 and older, and for treatment of allergic rhinitis Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 44 LRTAs: Adverse Effects Zileuton Zafirlukast Headache, dyspepsia, nausea, dizziness, insomnia, liver dysfunction Headache, nausea, diarrhea, liver dysfunction Montelukast has fewer adverse effects Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 45 LRTAs: Nursing Implications Ensure that the drug is being used for chronic management of asthma, not acute asthma Teach the patient the purpose of the therapy Improvement should be seen in about 1 week Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 46 LRTAs: Nursing Implications (cont’d) Advise patients to check with physician before taking over-the-counter or prescribed medications—there are many drug interactions Assess liver function before beginning therapy Teach patient to take medications every night on a continuous schedule, even if symptoms improve Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 47 Corticosteroids Antiinflammatory properties Used for chronic asthma Do not relieve symptoms of acute asthmatic attacks Oral or inhaled forms Inhaled forms reduce systemic effects May take several weeks before full effects are seen Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 48 Corticosteroids: Mechanism of Action Stabilize membranes of cells that release harmful bronchoconstricting substances These cells are called leukocytes, or white blood cells Increase responsiveness of bronchial smooth muscle to beta-adrenergic stimulation Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 49 Inhaled Corticosteroids beclomethasone dipropionate (Beclovent, Vanceril) triamcinolone acetonide (Azmacort) dexamethasone sodium phosphate (Decadron Phosphate Respihaler) fluticasone (Flovent, Flonase) Others Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 50 Inhaled Corticosteroids: Indications Treatment of bronchospastic disorders that are not controlled by conventional bronchodilators NOT considered first-line drugs for management of acute asthmatic attacks or status asthmaticus Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 51 Inhaled Corticosteroids: Adverse Effects Pharyngeal irritation Coughing Dry mouth Oral fungal infections Systemic effects are rare because low doses are used for inhalation therapy Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 52 Inhaled Corticosteroids: Nursing Implications Contraindicated in patients with psychosis, fungal infections, AIDS, TB Teach patients to gargle and rinse the mouth with lukewarm water afterward to prevent the development of oral fungal infections Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 53 Inhaled Corticosteroids: Nursing Implications (cont’d) If a beta-agonist bronchodilator and corticosteroid inhaler are both ordered, the bronchodilator should be used several minutes before the corticosteroid to provide bronchodilation before administration of the corticosteroid Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 54 Inhaled Corticosteroids: Nursing Implications (cont’d) Teach patients to monitor disease with a peak flow meter Encourage use of a spacer device to ensure successful inhalations Teach patient how to keep inhalers and nebulizer equipment clean after uses Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. 55