ASTHMA
Mirabelle Kwek
United States University
FNP 592 Common Illnesses Across the Lifespan
Dr. Jane Egbufoama
January 20, 2022
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Overview of Asthma
Common and chronic respiratory disease affecting 26 million people in the U.S. /300 million people globally
Most common chronic childhood disease
Prevalence is higher in African American than Caucasians
More predominant in males than females before puberty
Most of adult-onset cases diagnosed over age 40 are females
About 50% of children will have a reduced or resolved symptoms by early adulthood
Source: Morris, 2020
What is known about asthma? Asthma is a common and chronic respiratory disease affecting 26 million people in the United States and 300 million people globally. It is also the most common chronic disease in children. Its prevalence is higher among the African-American people compared to Caucasians. Moreover, it affects more males than females before puberty. However, after puberty, the prevalence of asthma is equal in both males and females. Among children diagnosed with asthma, about half of them will have a reduction or resolution of symptoms by early adulthood. Lastly, adults who were diagnosed with asthma after age 40 are mostly female.
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Symptoms of Asthma
Symptoms
Shortness of breath
Wheezing
Chest tightening
Cough
Limitation of expiratory flow of air
Symptoms and intensity vary over time
Source: GINA, 2021
Symptoms of asthma include shortness of breath or dyspnea; wheezing; tightness of the chest; cough; and limitation of expiratory flow of air. Symptoms vary over time and their intensity changes depending on triggering factors.
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Causes of Asthma
Genetics: some people are more susceptible to asthma than others
Allergens: pet dander, fungi, dust mites
Pollution/Irritants: cigarette smoke, fumes, plastic, wood dust
Chronic sinusitis or rhinitis
GERD
Aspirin
Exercise
Obesity
Source: Morris, 2020
What are the causes of asthma or triggering factors? One is genetics. Some people are more susceptible to asthma than others. Moreover, it tends to run in families. Thus, it is important to ask patients their family history of asthma. Another trigger is exposure to allergens such as pet dander, fungi or dust mites. Pollution and irritants can also cause asthma. Some examples of pollutants or irritants are cigarette smoke, chemical fumes, plastic and wood dust. Carpenters, painters, farmers and other workers who are constantly exposed to these irritants can develop work-related asthma. Having chronic sinusitis or rhinitis, as well as GERD can trigger asthma. Those with aspirin-sensitivity can develop asthma. Exercise is also known to induce asthma. Obesity is also associated with asthma. Those with high BMIs tend to have poorly controlled asthma, while weight loss aids in better asthma control.
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Review of Anatomy and Physiology
ANATOMY
Lung: lobes and segments
Major Areas of the Respiratory System
Conducting: nose to bronchioles
Respiratory: alveolar duct to alveoli
Bronchial Tree: distributes air until it reaches the sacs
Bronchi: smooth muscle/elastic fibers preserve wall integrity
Wall integrity changes: contraction/relaxation of smooth muscles
PHYSIOLOGY
Lung compliance: ability of the lungs to expand
Elastance: capability of lungs to return to rest
Source: Sinyor & Concepcion Perez, 2021
The respiratory system is composed of the lungs which are made up of lobes and segments. It is also composed of two major areas or zones. The first is the conducting area which encompasses the nose down to the bronchioles. The second is the respiratory zone which includes the alveolar duct up to the alveoli, where gas exchange happens. The bronchial tree then dispenses air throughout the lungs until it reaches the alveolar sacs. At the end of the trachea are the bronchi which divide into the left and right bronchi. Each bronchus then further divides. The bronchi is made up of smooth muscles and elastic fibers to preserve wall integrity. However, wall integrity changes due to the contraction and relaxation of smooth fibers caused by inflammatory mediators, bronchoconstrictors or bronchodilators. In the physiology of respiration, lung compliance is defined as the ability of the lungs to expand, while elastance is the capability of the lungs to return to its resting position. In asthma, normal mechanisms are altered due to inflammation which causes narrowing of the airway. Thus, the lungs do not expand to its maximum capacity leading to increased effort of breathing.
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Pathophysiology
Chronic Airway Inflammation
Bronchial Hyperresponsiveness
Bronchospasms
Shortness of breath Coughing Wheezing
Source: Morris, 2020
Chronic airway inflammation leads to an increase in bronchial hyperresponsiveness which then leads to bronchospasms. Then, when patients are exposed to pollutants, irritants, low temperatures, or activity, typical symptoms of asthma, such as shortness of breath, coughing, and wheezing, are activated.
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Categories of Asthma Severity
Intermittent
Symptoms during the day occur max of 2 days/week
Awaking at night: max of 2 days/month
SABA usage: max of 2 days/week
No activity interference between exacerbations
FEV1; FEV1/FVC ratio normal between exacerbations
Max of 1 exacerbation needing oral glucocorticoids/year
Mild persistent
Minimum of 2 asthma symptoms/week (but not every day)
Awakening at night: 3-4x/month due to asthma (not everyday)
SABA usage: min of 2 days/week (not everyday)
Some activity interference
FEV1 normal
Source: Fanta, 2021
The categories of asthma severity are: intermittent, mild persistent, moderate persistent, and severe persistent. It is important to categorize asthma severity because treatment will depend on this. Moreover, a patient in a category now may be placed in another category in the future. A patient is in the intermittent category when symptoms during the day occur for a maximum of 2 days in a week; the patient awakes at night twice per month due to asthma; the patient uses short acting beta-agonist or rescue inhaler for a maximum of 2 days in a week; the patient can do full activities in between exacerbations; FEV1 measurement and ratio of FEV1 to FVC is normal. On the other hand, mild persistent asthma is when the patient experiences a minimum of 2 asthma symptoms per week. However, symptoms should not be everyday to be placed in the mild persistent category. Other cues are that the patient wakes up at night 3-4 times per month due to asthma; the patient uses rescue inhaler at least 2 days in a week, but not everyday; there is some activity interference, and the FEV1 is normal.
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Categories of Asthma Severity (cont’d)
Moderate Persistent
Asthma symptoms, every day
Awakening at night: once/week
SABA usage: everyday for symptom relief
FEV1, >60 & <80% of predicted; FEC1/FVC below normal
Severe Persistent
Asthma symptoms, throughout the day
Awakening at night: every day
SABA usage: several times during the day
Limited activities
Source: Fanta, 2021
In moderate persistent asthma, the patient experiences asthma symptoms everyday and awakens at night once a week; uses rescue inhaler everyday for symptom relief; and the FEV1 is more than 60% but less than 80% of the predicted, and the ratio of FEV1 to FVC is below normal. In severe persistent asthma, asthma symptoms last throughout the day; the patient awakens every night due to asthma symptoms; and because asthma symptoms are throughout the day, the patient needs his rescue inhaler several times during the day. Also, the patient can do limited activities.
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Goals of Treatment
Control of asthma symptoms
Reduce intensity & frequency of symptoms
Maintain normal activity levels
Future risk reduction
Less asthma exacerbations
Less hospitalization/emergency care
Minimal or no adverse pharmacological effects
Source: Fanta, 2021
The goals of asthma treatment are control of symptoms and future risk reduction. Control of asthma symptoms means that there will be reduced intensity and frequency of symptoms such as cough, wheezing, shortness of breath, and tightness in the chest. When symptoms are reduced, patients can participate in their normal activities like going to school or work. Another goal is future risk reduction. Effective treatment means less asthma exacerbations; less need for hospitalizations or emergency care; and minimal to no adverse reactions from medications.
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Pharmacologic Treatment
Choosing a treatment for asthma
Age, symptom, lung function, risk for exacerbations, patient preference, practicality
Initiating therapy for patients diagnosed with asthma
SABA inhaler, albuterol OR
Low-dose glucocorticoid-formoterol inhaler
1-2 inhalations as needed
Stepwise approach to treatment
Source: Fanta, 2020
When choosing an asthma treatment for a patient, the following considerations must be made: the age of the patient, the symptoms presented; the patient’s lung function; the patient’s preference; and practicality, such as access to the medication, or the patient’s ability to use the device.
When initiating therapy for patients diagnosed with asthma, the patient should have immediate access to a SABA such as albuterol, or an alternative would be a low-dose glucocorticoid-formoterol inhaler, taking 1-2 inhalations as needed. Moreover, treatment of asthma uses a stepwise approach.
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Pharmacologic Treatment
Intermittent (Step 1)
Low-dose ICS-formoterol PRN OR
Take ICS when SABA is taken
Mild Persistent (Step 2)
Low-dose ICS-formoterol PRN OR
Low-dose ICS daily plus SABA PRN
Moderate Persistent (Step 3)
Low-dose ICS-formoterol daily plus low-dose ICS-formoterol PRN OR
Low dose ICS-LABA daily plus SABA PRN
Severe Persistent (Step 4)
Medium-dose ICS-formoterol daily plus low-dose ICS-formoterol PRN OR
Medium/high dose ICS-LABA daily plus SABA PRN
Source: GINA (2021)
Here, you can see the pharmacologic treatment of asthma based on a stepwise approach. If you noticed, there are 2 choices or tracks per step. Track 1 involves the use of a low-dose ICS-formoterol as a symptom reliever starting at Step 1, with the addition of ICS-formoterol to be taken daily for Step 3 and beyond. According to the Global Initiative for Asthma or GINA, the use of the combination of ICS-formoterol as reliever can reduce the risk of exacerbations as opposed to using a SABA reliever. On the other hand, you will notice that Track 2 uses SABA on as-needed basis on all steps with an addition of ICS to be used daily starting at Step 2. Before considering track 2, the provider needs to consult the patient on whether he or she can adhere to having a daily controller therapy. Otherwise, Track 1 should be chosen for the patient.
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Patient Education
Successful asthma management depends on patient-provider collaboration
Provide one-on-one patient education
Medication
How asthma develops
Concerns regarding prevention/treatment of symptoms
Enjoin family or the patient’s caregiver
Provide a personalized action plan that the patient can follow.
Avoidance of triggers
Treatment of other conditions
Source: Fanta, 2021
Successful asthma management depends on the collaboration of patient and provider. One-on-one patient education can elicit cooperation from the patient. For patient education, the topics to be included are the types of medication and how each medication is used, including a demonstration or a video presentation so that the patient can be guided accordingly. Another topic would be the pathophysiology of asthma so that the patient will have a clear understanding of the condition. The last topic would be concerns of the patient regarding prevention and treatment of asthma. Other topics can be included as well. During education, it is best that family members or the patient’s caregivers are present to support the patient. It is also important to provide the patient a personalized action plan with instructions that the patient can follow. Sample asthma action plans are available from various sources such as the National Asthma Education and Prevention Program and the Global Initiative for Asthma. It is also important to identify the patient’s triggers so that they can be avoided. Lastly, treatment of underlying conditions such as chronic sinusitis or rhinitis can help control asthma.
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References
Fanta, C. H. (2021). An overview of asthma management. UpToDate.
Retrieved January 20, 2022 from https://www.uptodate.com/contents/an-overview-of-
asthma-management
Global Initiative for Asthma (2021). 2021 GINA report. GINA. Retrieved January 18, 2022
Morris, M. J. (2020). Asthma. Medscape. Retrieved January 18, 2022 from
https://emedicine.medscape.com/article/296301-overview#a4
References
Sinyor, B., & Concepcion Perez, L. (2021). Pathophysiology of asthma.
StatPearls. StatPearls Publishing. Retrieved January 20, 2022 from
https://www.ncbi.nlm.nih.gov/books/NBK551579