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Home Healthcare Nurse:
doi: 10.1097/NHH.0b013e3182705c20
Feature: CE Connection

Chronic Obstructive Pulmonary Disease and Asthma

Hall, Mellisa DNP, ANP/FNP/GNP-BC

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Author Information

Mellisa Hall, DNP, ANP/FNP/GNP-BC, is an Assistant Professor of Nursing, College of Nursing and Health Professions, University of Southern Indiana, Evansville, Indiana.

The author and planners have disclosed that they have no financial relationships related to this article.

Address for correspondence: Mellisa Hall, DNP, ANP/FNP/GNP-BC, University of Southern Indiana, HP 2133, Evansville, IN 47712 (mhall@usi.edu).

For 33 additional continuing nursing education articles on respiratory topics, go to nursingcenter.com/ce.

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Abstract

Obstructive lung disorders are responsible for functional limitations and the deaths of millions of Americans. Chronic obstructive pulmonary disease (COPD) is in the top 5 leading causes of death and the incidence is climbing. Home healthcare and hospice nurses should be aware of current management strategies, including nonpharmacologic therapies. A case-study format is used to introduce the subject, a brief review of pathophysiology of COPD and asthma is discussed, and evidence-based treatment strategies are reviewed, including nursing management to improve patient function.

Ruthie had always considered herself a fun-loving kind of girl. She loved people and had worked as a beautician for more than 40 years. Ruthie had married her high school sweetheart, Paul, in 1958. As a young high school graduate, Paul had joined the Navy and they had lived happily in seven different port cities during his 27-year career.

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Beginning in mid-high school, Ruthie and Paul believed they should “Be Happy, Go Lucky” and started smoking menthol cigarettes. Both of their parents smoked, along with most of their aunts, uncles, cousins, and older siblings. The Surgeon General's report published in 1964, detailing the warnings of tobacco use (U.S. Department of Health, Education, and Welfare, 1964), had not concerned Ruthie or Paul in the least, until Paul's diagnosis of laryngeal cancer in 1998. After 3 years of aggressive treatments with radiation, chemotherapy, and surgery, Paul lost his battle to cancer leaving Ruthie alone after 41 years of marriage.

Ruthie gave up smoking immediately after Paul's cancer diagnosis. After having stopped smoking 15 years earlier, Ruthie could not understand how she could now be diagnosed with emphysema. Her emphysema seemed to control her entire world quickly, including the need for supplemental oxygen. Frustrated with her disability and perceived isolation due to oxygen use, Ruthie gave up her driver's license and moved into a small apartment close to the grocery store and beauty shop where she had worked. None of her family had ever had a lung disorder except for her two grandchildren, who are 2 and 5 years old, respectively.

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Chronic Obstructive Pulmonary Disease

Definitions and Epidemiology

Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death in the United States, responsible for 120,000 deaths annually (Centers for Disease Control, [CDC], 2011a). Only a fraction of smokers (15%-20%) are diagnosed with COPD, but smoking is the primary cause of the disorder. COPD may present as either chronic bronchitis or emphysema. Chronic bronchitis is characterized by recurrent bouts of coughing with mucous production. In comparison, emphysema slowly changes alveolar structure, leading to reduced gas exchange (Niewoehner, 2012). It is possible for both forms of COPD to exist in the same patient. Death rates from COPD have remained stable over the last 10 years (CDC, 2011a). Lower socioeconomic status is the highest risk factor for poor health outcomes with COPD (Eisner et al., 2011). Twenty-four million Americans are estimated to have COPD (Hersh, 2010) and 10 million Americans are actually diagnosed with COPD with confirmation of pulmonary function studies, but according to Hersh this percentage is thought to be grossly underestimated. COPD commonly manifests when patients reach their 60s with their lifetime exposures making them more susceptible (Rennard, 2012). The most common risk factors for COPD are presented in Table 1.

Table 1
Table 1
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Pathophysiology of Obstructive Lung Disorders

Both asthma and COPD share the similarity of obstructive-type lung disorders. COPD causes irreversible structural damage to alveoli while asthma is the result of reversible changes in airway hyperresponsive and inflammation (Niewoehner, 2012). Both COPD and asthma obstruct airflow into and out of the lungs. Table 2 presents a comparison of the pathophysiologic changes in COPD versus asthma. Figures 1 and 2 provide a visual representation of the pathologic changes of COPD and asthma.

Figure 1
Figure 1
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Figure 2
Figure 2
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Table 2
Table 2
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In COPD, destruction of the alveoli occurs due to an imbalance between elastase and anti-elastase. The imbalance causes the alveolar walls to lose elasticity, becoming permanently scarred. Tobacco smoke is a primary cause of the alveolar destruction. Deficiencies of alpha-antitrypsin, a protein usually secreted by the liver to protect lung tissue, is a genetic disorder responsible for 1% to 2% of COPD cases. Patients with alpha-antitrypsin deficiency are more susceptible to early onset of COPD than those with adequate amounts of alpha-antitrypsin (Niewoehner, 2012).

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Treatment Goals

Treatment goals for COPD include disease prevention, early diagnosis, help with ongoing symptoms, avoidance of exacerbations, and prevention of functional disability (Global Initiative for Chronic Obstructive Lung Disease [GOLD], 2011). Exacerbations should be controlled to promote functional independence. Exacerbations are correlated with poorer outcomes, and frequent severe exacerbations are correlated with higher mortality rates (Welte, 2009). Timely diagnosis of COPD is essential. Between 20% and 30% of patients go undiagnosed and do not receive adequate interventions (Lindberg et al., 2006).

Smoking is the primary cause of COPD. Smoking cessation reduces COPD exacerbations and leads to improved lung performance within 12 months (Au et al., 2009). Patients should be supported in cessation efforts, including behavioral modifications.

The level of physical activity in most COPD patients is minimal, but activity is important to improve circulation, maintain muscle tone, lower insulin resistance, and improve lipid profiles. Exercise also reduces the COPD patient's risk of blood clots, improves cardiac function, reduces dyspnea, and improves FEV1 (Hartman et al., 2010). Although there are no guidelines for physical activity in patients with COPD, based on the patient's tolerance, the usual 30 minutes per day, 5 days per week should be a goal (Agency for Healthcare Research and Quality [AHRQ], 2008).

According to Schneider et al. (2010), depression is common in patients with COPD, especially those with end-stage COPD. There are questions about the relationship between depression and smoking. Depression is linked to smoking initiation (Schneider et al., 2010). Depression may also be linked with the reduced ability to stop smoking. This makes it difficult to determine if depression was present before the actual diagnosis of COPD (Schneider et al., 2010). Either way, and whatever the cause, recognizing depression to provide appropriate assistance is important to maintaining optimal functional status.

COPD places older adults at higher risk for dizziness, poor nutritional status, low body mass index, and falling. This may be because of the expected age-related changes of the lung, including reduced inspiratory reserve, shallow inspirations, and weakening respiratory musculature. Patients 65 years and older are at a higher risk for impaired gas exchange due to COPD (Jarvis, 2012). Additional age-related changes of the lungs are listed in Table 3. Treatment goals for COPD should focus on maintaining functional status through muscle strengthening and physical activity.

Table 3
Table 3
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Medication Management

The pharmacologic treatment of COPD is currently built on four families of medications: inhaled anticholinergics, inhaled beta-2 agonists, corticosteroids, and xanthines. The combined use of these medications is based on the severity of the COPD (Table 4). Because bronchospasm in COPD is mediated by cholinergic stimuli, inhaled anticholinergics are the foundation of pharmacologic treatment for COPD. Inhaled anticholinergics do not cause the tremor compared to short-acting beta-2 agonist, making them better tolerated by all age groups, especially the elderly (Epocrates, 2012). Tiotropium is superior in efficacy compared to other scheduled anticholinergics (AHRQ, 2011). Inhaled beta-2 agonists are recommended for mild COPD only. The addition of corticosteroids and xanthines are based on the patient's stage of disease or symptomology. A newer category of medications to treat COPD are the phosphodiesterase-4 (PDE-4) inhibitors. Their mechanism of action is reduction of airway inflammation. PDE-4 inhibitors are used primarily to prevent COPD exacerbations associated with chronic bronchitis (Ferguson & Make, 2012). Examples of medications in each of these main categories are listed in Table 4.

Table 4
Table 4
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It is important for home healthcare nurses to reinforce correct inhaler technique to assure patients are benefiting from full dosages. Inhalers should be primed according to manufacturer's instructions. Because many inhalers have slightly different delivery modes, home care nurses should become familiar with the specific types of devices their patients are using. Many inhalers become compromised when exposed to moisture or light. Expiration dates should be respected. If a patient is on multiple inhalers, the inhaler that opens the airways should be used initially. For example, a short-acting inhaled beta-2 agonist should be used before an inhaled corticosteroid to receive the full benefit of both medications (Prescriber's Letter, 2009).

The majority of inhalers now use hydrofluoroalkane (HFA) as their propellant into the lower airways. An HFA propellant uses finer particles than previously used propellants. This may cause patients to perceive they are receiving less medication than they did while using their “old” inhaler. Patient education is necessary to explain why they may perceive less drug delivery.

Spacer devices are recommended to assure inhaled medication are deposited into the lower levels of the respiratory track to be effective. Without spacers, inhaled particles are often trapped in the oral cavity or the “dead space” of the respiratory track (AHRQ, 2011). If the patient cannot afford a spacer device, correct use of the inhaler device becomes even more vital.

Dry powder inhalers eliminate the need for synchronization of the inhaler device's hand-held activation with breathing. Dry powder devices depend only on the patient's inhalation effort for appropriate drug delivery. Dry powdered inhaled medications do not need additional chemicals used in propellant devices, reducing patients' risk for adverse side effects (AHRQ, 2011).

Use of nebulizers is recommended only if a patient is unable to understand or physically use a metered dose inhaler (MDI). Delivery of inhaled medications by a nebulizer device is not superior to MDI (AHRQ, 2011). Older patients or patients with end-stage COPD with vital capacities less than one and a half times their predicted tidal volume would also benefit from nebulized medications.

Oxygen is recommended for COPD treatment during severe exacerbations associated with hypoxemia or for patients with end-stage COPD. According to Medicare, patients qualify for oxygen therapy once oxygen levels reach 88% on room air; however, there is not a great deal of literature to support patients have improved outcomes with oxygen therapy unless the hypoxemia is severe (PaO2 < 55 mmHg) (Corrado et al., 2010).

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Asthma

Definitions and Epidemiology

Asthma, an obstructive lung disease similar to COPD, is characterized by hyperresponsiveness and inflammation of the bronchi (Kaufman, 2011). In the last 10 years the incidence of asthma has risen across all demographic groups. Over 24.6 million people are diagnosed with asthma, with Black men, Black children, and White women having the greatest upward incidence (Zahran et al., 2011). By age 20, asthma is more common in females, with women having over 10.5% of a greater likelihood of developing asthma compared to men (Kynyk et al., 2011). Ethnicity studies show that Puerto Rican children have the highest incidence of asthma, whereas Black children have the highest mortality rates (Forno & Celedon, 2009). It is anticipated that the rates of asthma in people over the age of 65 will double in the next 20 years due to aging of the population (Mathur, 2010).

Children have the greatest percentage of asthma compared to other age groups (Zahran et al., 2011). Asthma is more prevalent in lower socioeconomic groups, women, and non-Hispanic blacks (Zahran et al., 2011). Asthma is responsible for approximately 3,500 deaths annually in the United States compared with COPD's 125,000 (CDC, 2008). Treatment goals for asthma focus on patient education, including correct medication use and avoidance of environmental and emotional triggers (Shen et al., 2011).

Having an understanding of what triggers airway inflammation is a vital goal of asthma education. Additional treatment goals include teaching patients how to assess their worsening condition, how to adjust medications based on symptomology, and when to seek emergency care. In one study, dire economic limitations were evident when caring for patients in their homes. In that study, over 40% of patients report not being able to purchase their medications for asthma treatment due to lack of health insurance (one-half million patients) (Zahran et al., 2011). Instead of treating exacerbations at home, patients without appropriate medications may seek care from emergency departments.

Upper respiratory infections are another trigger for asthma exacerbations. Teaching patients to avoid crowds at time of community viral illnesses is important in preventing asthma flares. Respiratory syncytial virus (RSV) and influenza are two of the most prevalent community viruses causing asthma exacerbations (Guilbert & Denlinger, 2010). Chronic lower respiratory tract infections are associated with the developments of asthma due to persistent inflammation of airways. Some of the pathogens associated with chronic respiratory infections are listed in Table 5.

Table 5
Table 5
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The prevalence of asthma in the United States is increasing and it is expected to double in the elderly over the next 20 years (Mathur, 2010). Aging is associated with bronchial hyperresponsiveness, making elderly more susceptible to asthma development and asthma triggers. Although it is sometimes difficult to distinguish asthma from COPD, elderly asthma patients have higher levels of eosinophils in the blood and sputum, and a more pronounced improvement to bronchodilators on FEV1. It is possible to have both COPD and asthma as comorbidities. A history of tobacco exposure or other chemical toxins helps support the suspicion of COPD along with asthma. Due to the reduced ability in recognizing when symptoms are worsening, management of exacerbations are often delayed, and asthma outcomes in elderly are poorer (Mathur, 2010).

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Pathophysiology of Obstructive Lung Disorders

Asthma is considered a chronic illness that is characterized by inflammation and hyper-responsiveness of the bronchi and bronchioles. The primary pathogenic mechanism of asthma is inflammation of bronchial smooth muscle due to release of mast cells, eosinophils, lymphocytes, neutrophils, and macrophages. These inflammatory mediators infiltrate smooth muscles to cause sudden constriction. Many triggers can stimulate the release of inflammatory mediators including stress, infection, allergies, chemicals, and genetic factors (Winland-Brown & Porter, 2011). Asthma is not always reversible, and when the airflow reduction is not completely reversible, asthma patients are considered to have COPD (Rennard, 2012).

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Medication Management

The pharmacologic treatment of asthma includes three main categories: inhaled beta-2 agonists, inhaled corticosteroids, and leukotriene antagonists. Although not effective for rescue therapy, daily use of a long-acting beta-2 agonist limits asthma exacerbations, making them the most effective medications for asthma treatment (Montuschi et al., 2009). Long-acting beta-2 agonists are recommended in patients whose asthma symptoms require short-acting (rescue) beta-2 agonists dosed more than twice weekly (GOLD, 2011).

Use of spacer devices should be encouraged to receive the highest amount of the medication to the correct site within the lungs. Without correct use of the delivery device, up to 90% of the dosage will remain in the oropharynx and end up in the systemically absorbed through the gastrointestinal tract. Correct spacer use can limit this concern. Patients should be instructed to rinse their mouths out after inhaled steroid use to reduce the risk of candidiasis (Montuschi et al., 2009).

Leukotriene antagonists work by reducing the amount of available chemicals that cause airway hyperresponsiveness. These chemicals include leukotrienes C4, D4, and E4. By reducing these chemicals bronchoconstriction, hypersecretion of mucus, and eosinophil production in the lungs are reduced (Montuschi et al., 2009).

Inhaled chromones are another potential source of pharmacotherapy for asthma. Chromones prevent mast cell degranulation (reducing mucous production), and also have an anti-inflammatory effect on airways (Kelly, 2007). Inhaled chromones have been found to be less effective than inhaled corticosteroids.

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Implications for Home Care and Hospice Clinicians

It is important to address the patient's verbalized primary concerns. Home care nurses should acknowledge that asthma is a serious and sometimes life-threatening condition and well-deserving of respect. Patients should have reassurance that asthma is not associated with high mortality rates in the United States only because of access to medications. Ruthie should also be assured that when asthma develops in early childhood (less than 10 years old), more than 63% of asthma patients will have complete remission (Guilbert & Denlinger, 2010).

For Ruthie and other COPD patients, home care nurses should keep in mind that shortness of breath is most common in the morning, when many patients perform daily hygiene activities (Welte, 2009). Scheduling hygiene activities to later in the day should be considered when caring for patients with moderate to severe COPD.

Prevention remains the gold standard for COPD, specifically smoking avoidance. Once the patient has developed COPD other considerations for care include recommending annual flu vaccination, 30 minutes of aerobic activity a day, muscular strengthening exercises at least twice weekly, pulmonary rehabilitation, treating associated depression, and avoidance of further exposure to occupational and environmental lung hazards (GOLD, 2011). Avoidance of triggers and respiratory infection is the foundation for asthma control. Influenza vaccine is also recommended for anyone above 6 months of age (CDC, 2012).

Advance directives give the COPD patient an opportunity to determine how they would prefer to be treated at the end of life. As COPD, hypoxemia, and acidosis worsen in end-stage COPD, ventilator support including intubation or positive pressure oxygen delivery is needed to avoid death. All patients should be aware of the expected course of end-stage COPD and be presented with choices for care management such as hospice care opportunities compared to inpatient management. Patients' wishes should be documented by not only formal Advance Directive documents, but also their professional home care team. Family members should also be made aware of the patient's decisions. The goal in awareness is to provide continuity of care and to reduce as much emotional stress on the patient and family members as possible.

The prevalence of both COPD and asthma is on the rise (CDC, 2011b). Although asthma affects up to 7 million in the United States, COPD affects an estimated 24 million with mortality rates projected to increase by 30% over the next 10 years (Yawn, 2011; Zahran et al., 2011). It is vital that home healthcare and hospice nurse have an understanding of obstructive lung disorders to anticipate patients like Ruthie's needs and provide accurate teaching regarding current therapies.

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