Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc. CHAPTER 37 CHAPTER 37 Bronchodilators and Other Respiratory Drugs 6/9/20151Fall 2012

Diseases of the Lower Respiratory Tract COPD Asthma Emphysema Chronic bronchitis 6/9/20152Fall 2012

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 mucus 6/9/20153Fall 2012

Bronchial Asthma (cont’d) Alveolar ducts/alveoli remain open, but airflow to them is obstructed Symptoms Wheezing Difficulty breathing 6/9/20154Fall 2012

Asthma Three categories Allergic Idiopathic Mixed allergic-idiopathic 6/9/20155Fall 2012

Asthma (cont’d) Status asthmaticus Prolonged asthma attack that does not respond to typical drug therapy May last several minutes to hours Medical emergency 6/9/20156Fall 2012

Chronic Bronchitis Continuous inflammation of the bronchi and bronchioles Often occurs as a result of prolonged exposure to bronchial irritants 6/9/20157Fall 2012

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 6/9/20158Fall 2012

Drugs Used to Treat Asthma Long-term control Leukotriene receptor antagonists Inhaled steroids Long-acting beta 2 -agonists Quick relief Intravenous systemic corticosteroids Short-acting inhaled beta 2 -agonists 6/9/20159Fall 2012

Bronchodilators and Respiratory Drugs Bronchodilators Beta-adrenergic agonists Xanthine derivatives Anticholinergics Leukotriene receptor antagonists Corticosteroids 6/9/201510Fall 2012

Bronchodilators: Beta- Agonists Large group, sympathomimetic (adrenergic) Used during acute phase of asthmatic attacks Quickly reduce airway constriction and restore normal airflow Stimulate beta 2 -adrenergic receptors throughout the lungs 6/9/201511Fall 2012

Bronchodilators: Beta- Agonists (cont’d) Three types Nonselective adrenergics Stimulate alpha, beta 1 (cardiac), and beta 2 (respiratory) receptors Example: epinephrine Nonselective beta-adrenergics Stimulate both beta 1 and beta 2 receptors Example: metaproterenol (Alupent) 6/9/201512Fall 2012

Bronchodilators: Beta-Agonists (cont’d) Three types (cont’d) Selective beta 2 drugs Stimulate only beta 2 receptors Example: ALBUTEROL (PROVENTIL, VENTOLIN) FAST ACTING – RESCUE INHALER 6/9/201513Fall 2012

Beta-Agonists: Mechanism of Action Begins at the specific receptor stimulated Ends with dilation of the airways Activation of beta 2 receptors activates cyclic adenosine monophosphate (cAMP), which relaxes smooth muscle in the airway and results in bronchial dilation and increased airflow 6/9/201514Fall 2012

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 6/9/201515Fall 2012

Beta-Agonists: Adverse Effects Alpha and beta 1, 2 (epinephrine) Insomnia Restlessness Anorexia Vascular headache Hyperglycemia Tremor Cardiac stimulation 6/9/201516Fall 2012

Beta-Agonists: Adverse Effects (cont’d) Beta 1 and beta 2 - metaproterenol (Alupent) Cardiac stimulation Tremor Anginal pain Vascular headache Hypotension 6/9/201517Fall 2012

Beta-Agonists: Adverse Effects (cont’d) Beta 2 (albuterol) Hypotension OR hypertension Vascular headache Tremor 6/9/201518Fall 2012

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 6/9/201519Fall 2012

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 6/9/201520Fall 2012

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 6/9/201521Fall 2012

Nursing Implications (cont’d) Beta-agonist derivatives Albuterol, if used too frequently, loses its beta 2 -specific actions at larger doses As a result, beta 1 receptors are stimulated, causing nausea, increased anxiety, palpitations, tremors, and increased heart rate 6/9/201522Fall 2012

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 6/9/201523Fall 2012

METERED DOSE INHALER

OPTI CHAMBER (SPACER)

NEBULIZER

NEBULIZED MEDICATION 6/9/2015Fall

DRY POWDER INHALER

Peak Flow Meter

Anticholinergics Ipratropium bromide (Atrovent) and tiotropium (Spiriva) Slow and prolonged action Used to prevent bronchoconstriction NOT used for acute asthma exacerbations! 6/9/201531Fall 2012

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 6/9/201532Fall 2012

Anticholinergics: Adverse Effects Dry mouth or throat Nasal congestion Heart palpitations Gastrointestinal distress Headache Coughing Anxiety No known drug interactions 6/9/201533Fall 2012

Bronchodilators: Xanthine Derivatives Plant alkaloids: caffeine, theobromine, and theophylline Only theophylline is used as a bronchodilator Synthetic xanthines: aminophylline and dyphilline 6/9/201534Fall 2012

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) 6/9/201535Fall 2012

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 6/9/201536Fall 2012

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 6/9/201537Fall 2012

Xanthine Derivatives: Adverse Effects Nausea, vomiting, anorexia Gastroesophageal reflux during sleep Sinus tachycardia, extrasystole, palpitations, ventricular dysrhythmias Transient increased urination 6/9/201538Fall 2012

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) 6/9/201539Fall 2012

Xanthine Derivatives: Nursing Implications (cont’d) Report to physician: Palpitations Weakness Convulsions Nausea Dizziness Vomiting Chest pain 6/9/201540Fall 2012

Xanthine Derivatives: Nursing Implications (cont’d) Be aware of drug interactions with cimetidine, oral contraceptives, allopurinol, certain antibiotics, others 6/9/201541Fall 2012

Leukotriene Receptor Antagonists (LTRAs) Newer class of asthma medications Currently available drugs montelukast (Singulair) zafirlukast (Accolate) zileuton (Zyflo) 6/9/201542Fall 2012

LTRAs: 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 6/9/201543Fall 2012

LTRAs: Mechanism of Action (cont’d) LTRAs 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 6/9/201544Fall 2012

LTRAs: 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 6/9/201545Fall 2012

LTRAs: 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 6/9/201546Fall 2012

LTRAs: Adverse Effects Zileuton Headache, dyspepsia, nausea, dizziness, insomnia, liver dysfunction Zafirlukast Headache, nausea, diarrhea, liver dysfunction Montelukast has fewer adverse effects 6/9/201547Fall 2012

LTRAs: 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 6/9/201548Fall 2012

LTRAs: 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 6/9/201549Fall 2012

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 6/9/201550Fall 2012

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 6/9/201551Fall 2012

Inhaled Corticosteroids beclomethasone dipropionate (Beclovent, Vanceril) triamcinolone acetonide (Azmacort) dexamethasone sodium phosphate (Decadron Phosphate Respihaler) fluticasone (Flovent, Flonase) Others 6/9/201552Fall 2012

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 6/9/201553Fall 2012

Inhaled Corticosteroids: Adverse Effects Pharyngeal irritation Coughing Dry mouth Oral fungal infections Systemic effects are rare because low doses are used for inhalation therapy 6/9/201554Fall 2012

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 6/9/201555Fall 2012

NURSING CONSIDERATIONS: ALL INHALED MEDICATIONS 5 MINUTES BETWEEN DRUGS BRONCHODILATORS FIRST RINSE MOUTH AFTER STEROIDS USE FAST ACTING INHALED MED FOR ACUTE EPISODES *ALBUTEROL – RESCUE INHALER

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 6/9/201557Fall 2012