Integrated Cardiopulmonary Pharmacology Third Edition

Transcription

1 Integrated Cardiopulmonary Pharmacology Third Edition Chapter 13 Pharmacologic Management of Asthma, Chronic Bronchitis, and Emphysema

2 Multimedia Directory Slide 7 Slide 12 Slide 60 COPD Video Passive Smoking and Asthma Video Smoking Cessation Video

3 Objectives Upon completion of this chapter, you will be able to Explain the pathophysiology of asthma and chronic obstructive pulmonary disease (COPD) Distinguish among the various forms of COPD

4 Objectives Recognize the importance of treatment guidelines in the management of asthma and COPD Develop a pharmacologic regimen for asthma, chronic bronchitis, and emphysema Develop a monitoring and educational plan for asthma, chronic bronchitis, and emphysema

5 COPD COPD represents progressive, irreversible conditions that include emphysema and chronic bronchitis. Asthma is an obstructive disease with reversibility. Often, these diseases coexist.

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7 COPD Video Click the screenshot to view a video on the topic of COPD. Back to Directory

8 Asthma Chronic inflammatory disease of the airways that affects 20 million people in the United States. Most common chronic disease of children and young adults.

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10 Asthma Symptoms Episodic wheezing Shortness of breath Cough Chest tightness

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12 Passive Smoking and Asthma Video Click the screenshot to view a video on the topic of passive smoking and asthma. Back to Directory

13 Asthma Treatment The National Asthma Education and Prevention Program (NAEPP) established the following goals Symptom prevention. Maintenance of normal or near-normal lung function. Maintenance of normal activity levels (including exercise and other physical activity).

14 Goals of Asthma Treatment Preventing exacerbations and minimizing need for emergency department visits or hospitalizations. Providing optimal pharmacotherapy with few or no adverse effects. Meeting patients and families expectations of satisfaction with asthma care.

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16 Asthma Medication The NAEPP report groups asthma into two categories: long-term control and quick relief. Quick-relief medications are used for rapid relief in an acute exacerbation. Long-term control medications are used to prevent symptoms and maintain control of persistent asthma.

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19 Table 13 6 Long Term Asthma Control Medications

20 Asthma Management A stepwise approach is recommended for the pharmacologic treatment of asthma. All patients should have quick-relief medications to treat acute attacks. Patient and family education is critical.

21 Insert Figure 13-1 Figure 13 1: Stepwise Approach to Asthma Management Based on Level of Asthma Severity (for adults and children > 5 years of age) Source: Modified from NAEPP 2007 update and GINA.

22 Figure 13 1 : Stepwise Approach to Asthma Management Based on Level of Asthma Severity (for adults and children > 5 years of age) Source: Modified from NAEPP 2007 update and GINA.

23 Management of Acute Asthma Exacerbations Patient must monitor and recognize when asthma is getting worse. Every patient should have a written plan of action.

24 Insert Figure 13-2 Figure 13 2: Sample Action Plan for Management of Asthma

25 Need for Hospitalization Quick-relief medications given either via MDI or SVN; SVN if pulmonary function less than 50% of predicted. Use supplemental oxygen if hypoxemic. If symptoms persist, use systemic steroids and anticholinergic agents.

26 Need for Hospitalization May also receive inhaled or IV magnesium sulfate and aggressive oxygen therapy In general, may be discharged when pulmonary functions return to 70% predicted range.

27 Insert Figure 13-3 Figure 13 3: Management of Acute Asthma Exacerbations Source: Modified from the NAEPP3.

28 Figure 13 3 : Management of Acute Asthma Exacerbations Source: Modified from the NAEPP3.

29 Patient Education Critical component that should include Avoidance of triggers. Understanding the difference between control medications and relief medications. Proper technique for the use of inhalers and related devices. How to monitor severity of asthma and recognize when it is becoming worse, what to do should this happen, and when to seek help.

30 Asthma Treatment Goals According to the NAEPP3, the goals are Prevent troublesome and chronic symptoms. Infrequent use of a (Short Acting Bronchodilator Agent (SABA) ( 2 days/week). Maintain near normal pulmonary function. Maintain normal activity levels. Meet patients and families expectations of satisfaction with asthma care.

31 Asthma Treatment Goals Reduce risk by Prevent exacerbations and the need for ED visits and/or hospitalizations. Prevent progressive loss of lung function; for children, reduced growth. Provide optimal pharmacotherapy with minimal or no adverse effects.

32 COPD According to 2001 estimates, 12.1 million people in the United States have COPD. COPD is a major disability with huge economic cost. Primary etiology is tobacco smoke. Air pollution, occupational exposure, asthma, and nonspecific airway hyperresponsiveness may all play a role in the development of COPD.

33 Emphysema In the past, it was customary to divide persons with COPD into two categories Those with emphysema ( pink puffers ) Those with chronic bronchitis ( blue bloaters ). However, most persons with COPD have features of both of these diseases.

34 Emphysema An estimated 2 million people in United States have emphysema, with approximately 100,000 cases caused by genetic deficiency of alpha1-antitrypsin (α 1 -AT).

35 Emphysema: Primary Clinical Features Dyspnea on exertion. Nonproductive cough. Pink puffer appearance due to breathing with all the accessory muscles. Weight loss.

36 Alpha1-Antitrypsin (α 1 -AT) Deficiency α 1 -AT is a glycoprotein found in extracellular and intracellular fluid. It is essential in protecting the lung against naturally occurring proteases that have the ability to break down the elastin and macromolecules in lung tissue.

37 Alpha1-Antitrypsin (α 1 -AT) Deficiency Patients with this deficiency tend to develop emphysema at a younger age (in their 40s or 50s) than do patients with emphysema due to other causes.

38 Alpha 1 -Antitrypsin (α 1 -AT) Deficiency Smoking further accelerates the process, by stimulating the release of neutrophil elastase. The syndrome of α 1 -AT deficiency is perceived by most clinicians as being rare, but the reality is that most patients with α 1 -AT deficiency go undiagnosed and are treated simply as people with emphysema.

39 Alpha1-Antitrypsin (α 1 -AT) Deficiency Manifestations of severe α 1 -AT deficiency involve the lungs, the liver, and the skin, and the major clinical feature is emphysema. The disorder is detected by a decreased level of α 1 -AT to below a so-called protective value of 80 mg/dl. This is in comparison to normal serum levels of 150 to 350 mg/dl.

40 Chronic Bronchitis Chronic bronchitis is more common than emphysema, with more than 9 million persons in the United States suffering from it. Cigarette smoking is the major causative factor in up to 90% of cases.

41 Chronic Bronchitis Patients with chronic bronchitis have an increase in size and number of the mucussecreting glands, narrowing and inflammation of the small airways, obstruction of airways caused by narrowing and mucus hypersecretion, and bacterial colonization of the airways. Acute episodes are usually brought on by respiratory tract infection.

42 Chronic Bronchitis The usual clinical presentation of chronic bronchitis begins with morning cough productive of sputum. Wheezes may be present, and an increase in the anteriorposterior diameter of the chest (the classic barrel chest ) may be present with both emphysema and chronic bronchitis.

43 Chronic Bronchitis Respiratory infections trigger acute exacerbations in COPD patients, especially in elderly patients with chronic bronchitis.

44 Chronic Bronchitis Patients present with hypersecretion of mucus and then, owing to their decreased removal of bronchial secretions by ciliary activity, are at increased likelihood of developing pneumonia and significant lung damage from the infection.

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46 Prevention: The Key to Treatment of COPD Smoking cessation is only method of preventing or slowing progression of COPD. Tobacco dependence is a powerful addiction.

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48 Measuring Level of Addiction It is important to somehow quantify the patient s addiction to nicotine. The Fagerstrom Test for Nicotine Dependence (FTND) is a good tool to help quantify this addiction.

49 Measuring Level of Addiction A score of 6 or higher on the FTND indicates a high level of nicotine dependence. Patients in this category will have difficulty overcoming the initial withdrawal symptoms of nicotine and will benefit the most from pharmacotherapy to aid cessation.

50 Measuring Level of Addiction Even a person with a lower score on the FTND may benefit from nicotine replacement therapy or use of bupropion (Zyban) to aid in cessation.

51 Insert Figure 13-4 Figure 13 4: The Fagerstrom Test for Nicotine Dependence

52 Smoking Cessation Therapies The patient s preference has a great deal to do with which drug therapy (if any) is chosen. The best pharmacotherapy will not be successful until the patient has truly decided to quit.

53 Smoking Cessation Therapies Pharmacotherapy alone is rarely a means to successful cessation in nicotineaddicted patients. Patients should be encouraged to seek educational and behavioral modification therapy for smoking cessation and to use pharmacotherapy as an aid to these programs.

54 Nicotine Replacement Therapy (NRT) NRT can be adjusted to substitute partially for the nicotine the patient inhales through smoking cigarettes. NRT delivers less nicotine than received through smoking but enough to decrease the intensity of nicotine withdrawal symptoms.

55 Nicotine Replacement Therapy (NRT) Even though nicotine is still being ingested, the carcinogens that would be delivered through smoking are not. Currently, there are four methods of NRT: the patch, nicotine gum/lozenge, nicotine nasal spray, and the nicotine oral inhaler.

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57 Table 13 9 Nicotine Replacement Therapies, Bupropion, Varenicline

58 Varenicline (Chantix ) This medication is a partial agonist of the nicotinic acetylcholine receptor and its efficacy may be related to two mechanisms. First, it binds to and stimulates the receptor thereby reducing the craving for nicotine.

59 Varenicline (Chantix ) Second, since it binds to the receptor with high affinity, it may block inhaled nicotine from working.

60 Smoking Cessation Video Click the screenshot to view a video on the topic of smoking cessation. Back to Directory

61 Vaccinations Influenza vaccination has been shown to decrease serious illness and mortality in COPD patients by about 50%. Although there is less evidence for its effectiveness, pneumococcal vaccine is also recommended for COPD patients.

62 Vaccinations The currently recommended vaccine (Pneumovax) incorporates the antigens of 23 strains of bacteria that are responsible for 90% of the pneumococcal pneumonia occurring in the United States. This vaccine is generally given as a one-time dose.

63 COPD Treatment Goals The "GOLD Guidelines, prepared by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) is a valuable resource.

64 COPD Treatment Goals According to the GOLD Guidelines, there are four components to patient management Assessing and monitoring the disease. Reducing risk factors. Managing stable disease. Managing exacerbations.

65 COPD Treatment Goals Goals of therapy are to prevent disease progression, relieve symptoms, improve exercise tolerance, improve overall health status, prevent and treat exacerbations and other complications, and reduce mortality.

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67 Drugs Used to Treat COPD β 2 -agonists and anticholinergics β 2 -agonists produce less bronchodilation in COPD than in asthma. Patients with COPD respond better to anticholinergic agents than do patients with asthma.

68 Drugs Used to Treat COPD Current thinking is that β 2 -agonists and anticholinergic agents are equally effective as bronchodilators in COPD, although a given patient may respond better to one than to another. The use of a combination product containing both albuterol and ipratropium (e.g., Combivent) in the same MDI may help the patient by simplifying therapy.

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70 Drugs Used to Treat COPD Theophylline at one time was probably the most common agent used in this patient population. However, its potent toxicities and the availability of newer agents have caused it to fall from favor.

71 Drugs Used to Treat COPD The agent is still of value for the management of both asthma and COPD in patients who are not capable of using an MDI effectively or who are inadequately controlled with their inhaled medications.

72 Drugs Used to Treat COPD Theophylline and other xanthine derivatives improve respiratory muscle function, stimulate the respiratory center, and enhance activities of daily living in patients.

73 Drugs Used to Treat COPD In sharp contrast to the therapy of asthma patients, anti-inflammatory drugs are of far less benefit in COPD patients. While inflammation plays a role in the development of COPD, it is not allergic in nature and responds to therapy differently than does asthma.

74 Drugs Used to Treat COPD Inhaled corticosteroids may be of benefit in patients with Stage III and IV COPD if they are having repeated exacerbations. Oral corticosteroids are recommended only for short-term use in patients with moderate to severe exacerbations.

75 Drugs Used to Treat COPD Mucokinetic agents (organic iodide, guaifenesin, acetylcysteine, etc.) have had little objective information published supporting their value in the treatment of COPD. Oxygen therapy is often needed to maintain normal PaO 2 levels and to decrease the work of breathing associated with COPD.

76 Drugs Used to Treat COPD Infection is a common cause of exacerbation in patients with COPD. Therefore, antibiotics are recommended for patients who are showing signs of exacerbation and having an increase in sputum purulence.

77 Drugs Used to Treat COPD The organisms most frequently responsible for infection are Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis.

78 Drugs Used to Treat COPD In the past, prophylactic antibiotics were prescribed for some patients to prevent exacerbations; however, this practice is now discouraged in an attempt to prevent the development of resistant organisms.

79 Drugs Used to Treat COPD α 1 -antitrypsin (α 1 -AT) augmentation therapy is accomplished by administering α 1 proteinase-inhibitor (e.g., Prolastin, Aralast, Zemaira). This therapy is appropriate in nonsmoking, younger patients with severe α 1 -AT deficiency and associated emphysema.

80 Drugs Used to Treat COPD These products must be given by intravenous infusion on a weekly basis and are very costly.

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