Asthma: Aetiologies, Symptoms, Aids to Diagnosis and Management Flashcards
1
Q
What is obstructive airways disease?
A
Obstructive airways disease refers to conditions that cause narrowing of the large, medium-sized, and small airways (bronchi), leading to difficulties in breathing. Examples of obstructive airways diseases include asthma, COPD (chronic obstructive pulmonary disease), and bronchiectasis.
2
Q
What are the consequences of obstructive airways disease?
A
Obstructive airways diseases result in air trapping and hyperinflation, making it harder for air to flow out of the lungs during expiration.
3
Q
What is spirometry?
A
Spirometry is a common diagnostic test used to assess lung function. It measures the amount and speed of air that can be inhaled and exhaled.
4
Q
How is obstructive airways disease diagnosed using spirometry?
A
In obstructive airways disease, spirometry typically shows a decreased forced expiratory volume in 1 second (FEV1), with a relatively preserved forced vital capacity (FVC). This leads to a decreased FEV1/FVC ratio, which is commonly defined as less than 70%.
FEV1 = Forced Expiratory Volume in 1 second.
FVC = Forced Vital Capacity.
5
Q
How is asthma defined?
A
Asthma is a reversible, obstructive airways disease characterized by inflammation, hyper-responsiveness, and narrowing of the bronchial tree. It occurs in susceptible individuals due to various triggers.
6
Q
What are the main characteristics of asthma?
A
Asthma is characterized by recurrent attacks of breathlessness and wheezing. The severity and frequency of these attacks can vary from person to person.
7
Q
How is asthma diagnosed?
A
There are no consistent diagnostic criteria for asthma. Diagnosis is typically based on the presence of symptoms such as wheezing, breathlessness, chest tightness, and cough. Additionally, there is usually evidence of variable airflow obstruction.
8
Q
What is the epidemiology of asthma?
A
In the UK, the mortality rate for asthma is around 4 per 100,000 individuals.
9
Q
What is the etiology of asthma?
A
Asthma has a multifactorial etiology. It occurs when a genetically susceptible individual with atopy (a tendency to produce high amounts of Immunoglobulin E, IgE) is exposed to certain environmental factors. Atopy is often associated with a high prevalence of asthma, allergic rhinitis, urticaria, and eczema.
10
Q
What is atopy?
A
Atopy refers to the tendency of individuals to produce high levels of IgE antibodies when exposed to small amounts of an antigen. Atopic individuals often demonstrate positive reactions to antigens on skin prick testing, indicating their sensitivity or allergy to specific allergens.
11
Q
How can atopy be measured or demonstrated?
A
Atopy can be measured by detecting specific IgE antibodies to allergens in the serum. This can be done through blood tests. Additionally, skin prick testing can be used to demonstrate allergies to specific allergens by observing positive reactions on the skin.
12
Q
What is the process of airway inflammation in asthma?
A
Airway inflammation in asthma involves the sensitization of atopic individuals followed by inhalation of allergens. It results in a two-phase response: an early reaction occurring within 20 minutes and a late reaction occurring 6-12 hours later. T-helper lymphocytes, particularly Th2 cells, regulate the inflammatory response by secreting pro-inflammatory interleukins and stimulating the release of IgE antibodies by plasma cells.
13
Q
How do IgE antibodies contribute to the pathophysiology of asthma?
A
IgE antibodies bind to receptors on mast cells and eosinophils, triggering the release of histamine, prostaglandins, and cysteinyl leukotrienes. These mediators cause bronchoconstriction of the airways, which occurs within minutes of exposure to allergens. The targets of these mediators serve as therapeutic targets in asthma management.
14
Q
What are the characteristics of the late phase response in asthma?
A
The late phase response in asthma involves the infiltration of the smooth muscle layer by various immune cells, desquamation of epithelial cells, mucus gland hyperplasia, hypertrophy and hyperplasia of airway smooth muscle, increased permeability of blood vessels, increased mucus production, mucus plugging, and acute inflammation resulting in edema. These processes contribute to airway narrowing and obstruction.
15
Q
What are the consequences of chronic and severe asthma?
A
In chronic and severe asthma, there is remodeling of the airways with collagen deposition and fibrosis of the airway wall, leading to fixed narrowing. Eosinophils are associated with acute asthma, while neutrophils are associated with persistent airway inflammation and “steroid-dependent” asthma.
16
Q
What are some environmental triggers for acute asthma?
A
Environmental triggers for acute asthma include animal dander, house dust mites (HDM), grass and tree pollen, mold, viral and bacterial infections, atmospheric pollution (such as ozone, sulfur dioxide, nitrogen oxide, fumes), thunderstorms, perfumes, hair sprays, plug-ins, cigarette smoking (active and passive), indoor fires, chlorine (from swimming pools or cleaning products), paints, and exposure to cold air or sudden changes in temperature.
17
Q
Which drugs can trigger acute asthma?
A
Certain drugs can trigger acute asthma, including aspirin, non-steroidal anti-inflammatory drugs (NSAIDs), and beta-blockers. These medications may cause bronchoconstriction and worsen asthma symptoms in susceptible individuals.
18
Q
What are some physiological triggers for acute asthma?
A
Physiological triggers for acute asthma include pregnancy, the premenstrual period, and exercise. These factors can lead to increased airway responsiveness and exacerbate asthma symptoms in susceptible individuals.
19
Q
What is occupational asthma?
A
Occupational asthma refers to asthma that is triggered or worsened by exposure to specific substances or conditions in the workplace. Various occupational agents such as chemicals, dust, fumes, and allergens can induce or exacerbate asthma symptoms in susceptible individuals.
20
Q
What are the symptoms of acute asthma during exacerbations?
A
During exacerbations of acute asthma, individuals may experience breathlessness, chest tightness, wheezing (a high-pitched whistling sound during breathing), and coughing. These symptoms can be distressing and indicate a worsening of asthma.
21
Q
What are the symptoms of acute asthma between exacerbations?
A
Between exacerbations, individuals with asthma may experience periods of being completely well. They may also have mild chest tightness, occasional wheezing, or a dry cough. Some individuals may have cough-variant asthma, where cough is the predominant symptom.
22
Q
Is there a diurnal variability of symptoms in acute asthma?
A
Yes, there is diurnal variability in asthma symptoms. Asthma symptoms tend to be worse at night and in the early morning. This pattern is linked to the body’s circadian rhythm, and individuals may experience increased bronchial constriction and inflammation during these times.
23
Q
What signs may be present during an acute asthma exacerbation?
A
During an acute asthma exacerbation, clinical examination may reveal signs such as tachypnea (rapid breathing) and tachycardia (elevated heart rate). These signs indicate increased effort in breathing and the body’s response to reduced airway function.
24
Q
What are the characteristic respiratory sounds in acute asthma exacerbation?
A
Acute asthma exacerbation is often accompanied by polyphonic wheezing, which is the presence of wheezing sounds during both inspiration and expiration. These wheezes are caused by the narrowing of the airways and the turbulent airflow passing through them.
25
What signs suggest hyperinflation in acute asthma?
In severe cases of acute asthma, signs of hyperinflation may be observed. These can include cyanosis (bluish discoloration of the skin and mucous membranes due to inadequate oxygenation), a silent chest (reduced breath sounds), and bradycardia (a slow heart rate). These signs indicate severe airway obstruction and compromised respiratory function.
26
What blood tests are commonly used in the investigation of suspected asthma?
In the investigation of suspected asthma, blood tests such as a full blood count may be performed. A raised eosinophil count is often observed in asthma, indicating the presence of eosinophilic inflammation. Additionally, tests measuring IgE levels, such as the radioallergosorbent test (RAST), may be conducted if a specific allergy is suspected.
27
What diagnostic tests can be used to assess lung function in asthma?
Several diagnostic tests are used to assess lung function in asthma. These include spirometry, which measures the volume and flow of air during forced breathing maneuvers. A full lung function test with reversibility to bronchodilator, such as salbutamol, can also be performed to determine the degree of airflow obstruction and assess the response to bronchodilator therapy. Methacholine or histamine provocation tests may be used to assess airway hyperresponsiveness, which is a characteristic feature of asthma.
28
What imaging tests may be conducted in the investigation of suspected asthma?
Imaging tests such as a chest X-ray (CXR) and high-resolution computed tomography (HRCT) may be conducted in the investigation of suspected asthma. CXR can help identify other respiratory conditions that may mimic asthma, while HRCT is useful for evaluating lung structure and assessing the presence of conditions like emphysema or bronchiectasis, which can coexist with asthma.
29
What other tests can be performed in the investigation of suspected asthma?
Other tests that can be performed in the investigation of suspected asthma include sputum analysis, which involves examining the sputum for microbiological factors and conducting a differential cell count. This helps identify any underlying infections or inflammation. Peak flow measurements and PEF (peak expiratory flow) homework, where the patient records their PEF measurements in the morning and evening for several weeks, can provide valuable information about diurnal variation and variability, which are characteristic features of asthma.
30
What spirometry results indicate airflow obstruction in asthma?
Spirometry is a commonly used test to assess lung function in asthma. The spirometry results that indicate airflow obstruction include reduced forced expiratory volume in 1 second (FEV1) and a decreased ratio of FEV1 to forced vital capacity (FVC), with an FEV1/FVC ratio less than 70%. These findings suggest the presence of airflow limitation and obstruction in the large and small airways.
31
How is reversibility to bronchodilator assessed in spirometry?
Reversibility to bronchodilator is assessed in spirometry by measuring the change in lung function after administering a bronchodilator medication, such as inhaled salbutamol. The criteria for reversibility include an increase in FEV1 by at least 15% of the baseline value or by more than 200 ml, measured 20 minutes after the administration of 200 mcg of inhaled salbutamol. Patients with asthma typically show significant reversibility, whereas patients with chronic obstructive pulmonary disease (COPD) show little to no reversibility.
32
What are the lung function test findings in asthma?
In asthma, lung function tests may reveal an increase in total lung capacity (TLC) and residual volume (RV) due to air trapping caused by the narrowing of the airways. However, the transfer factor or diffusing capacity (TLCO/DLCO) is usually normal in asthma, indicating that the ability of the lungs to transfer oxygen from inhaled air into the bloodstream is not significantly affected.
33
What is Fractional Exhaled Nitric Oxide (FeNO)?
Fractional Exhaled Nitric Oxide (FeNO) is a measure of airway eosinophilic inflammation, which is commonly associated with asthma. It is a non-invasive test that measures the level of nitric oxide in the breath. Elevated FeNO levels (> 40 ppb) are suggestive of airway inflammation and support the diagnosis of asthma. FeNO testing can be performed in both general practitioner (GP) offices and hospital clinics. It can also be used to monitor treatment response and assess compliance in asthma management.
34
What are the imaging options for asthma?
When imaging is required for asthma evaluation, two common options are available: chest X-ray (CXR) and high-resolution computed tomography (HRCT).
Chest X-ray (CXR):
CXR findings may be normal in mild asthma.
In more severe cases, CXR may show hyperinflation with increased lung volumes and flattened diaphragms.
Other CXR features may include the visualization of 6 anterior ribs or 10 posterior ribs in the mid-clavicular line and a more vertical and narrow heart.
High-resolution computed tomography (HRCT):
HRCT is more sensitive than CXR in detecting abnormalities in asthma.
It can show air trapping, which is a characteristic feature of asthma due to narrowed airways.
HRCT may also provide additional information about bronchial wall thickening, mucus plugging, and other structural changes in the airways.
35
What are some key strategies for managing asthma?
Avoiding allergens if possible, utilizing inhaled therapy, and considering oral therapy.
36
What are the aims of pharmacological management in asthma?
Achieving symptom control: minimal symptoms during day and night, minimal need for a reliever, and no limitation of physical activity.
Attaining the best possible pulmonary function: FEV1 or PEF > 80% predicted or best.
Preventing exacerbations.
Reducing morbidity and mortality.
Minimizing side effects.
37
How does the British Thoracic Society (BTS) provide guidelines for asthma management?
The BTS provides comprehensive guidelines that outline evidence-based recommendations for the management of asthma.
38
What does the management of acute exacerbation of asthma involve?
The management of acute exacerbation of asthma includes prompt assessment, administration of appropriate bronchodilators and corticosteroids, oxygen therapy if needed, and monitoring of respiratory function.
39
Which receptors are present in the bronchial mucosa?
β2-adrenoceptors are found in the smooth muscle of the airways from the trachea to the terminal bronchioles. Muscarinic cholinergic receptors also receive parasympathetic nerve supply
40
What are the routes of medication administration for the lungs?
Inhaled: Medications can be delivered through inhalers or nebulizers, allowing direct deposition into the lungs. The technique of inhalation is important for effective drug delivery.
Oral: Medications taken orally are absorbed in the gut. This route is not technique-dependent.
Intravenous: Medications administered intravenously have systemic effects throughout the body. This route is not technique-dependent but may have more side effects.
Intramuscular: Medications injected into the muscle tissue.
Subcutaneous: Medications injected beneath the skin.
41
How do inhalers and nebulizers contribute to drug deposition in the lungs?
Inhalers and nebulizers directly deposit the drug into the lungs, allowing for rapid absorption of the medication.
42
What is an aerosol in the context of drug deposition in the lungs?
An aerosol is a suspension of fine particles of varying sizes. When inhaled, a small dose of the medication is dispersed widely over the airways and alveolar surfaces.
43
How do the systemic side effects of inhaled therapy compare to oral or intravenous treatment?
Inhaled therapy generally has fewer systemic side effects compared to oral or intravenous treatment. The medication acts primarily in the lungs, reducing the risk of systemic effects.
44
What is the efficiency of drug deposition in the lungs through inhaler systems?
Inhaler systems, regardless of inhaler technique, are relatively inefficient. Only 8-15% of the drug reaches the lung, regardless of the proficiency of inhalati
45
How can particle distribution within the lungs be measured?
Particle distribution within the lungs can be measured by radio-labeling the drug and using a gamma camera to quantify deposition.
46
What are the factors that determine drug deposition in the lungs?
The factors that determine particle deposition in the lungs include the size of the particle, inspiratory flow rate, and the distance the particle needs to travel, which is determined by the method of inhalation.
47
What factors favor distal particle sedimentation in the lungs?
Distal particle sedimentation is favored by small particle size and a slow flow rate.
48
What do the abbreviations SABA, LABA, SAMA, LAMA, and ICS stand for in the context of inhaled therapy?
SABA: Short-acting β-2 agonist
LABA: Long-acting β-2 agonist
SAMA: Short-acting muscarinic antagonist
LAMA: Long-acting muscarinic antagonist
ICS: Inhaled corticosteroid
49
How do β-2 agonists work in the treatment of asthma and COPD?
β-2 agonists act on the β-2 receptors in the smooth muscle of the bronchial mucosa. They activate adenylate cyclase, leading to an increase in cyclic adenosine monophosphate (cAMP) levels. This activates protein kinase A, phosphorylating several target proteins within the cell. Ultimately, this decreases intracellular calcium concentration by actively removing calcium from the cell into intracellular stores, leading to bronchodilation.
Gs pathway
50
What are some examples of short-acting β-2 agonists (SABA) used in the treatment of asthma and COPD?
Examples of short-acting β-2 agonists (SABA) include salbutamol (Ventolin) and terbutaline (Bricanyl).
51
What are some examples of long-acting β-2 agonists (LABA) used in the treatment of asthma and COPD?
Examples of long-acting β-2 agonists (LABA) include salmeterol and formoterol.
52
What are the core drugs commonly used in the treatment of asthma and COPD?
The core drugs commonly used in the treatment of asthma and COPD include salbutamol (SABA) and salmeterol (LABA).
53
What are the effects of stimulating the β2 adrenoreceptor?
Relaxation of smooth muscle: Stimulation of the β2 adrenoreceptor activates adenylate cyclase, leading to an increase in cyclic adenosine monophosphate (cAMP), resulting in bronchodilation.
Stabilization of mast cells and inhibition of inflammatory mediator release.
Enhanced mucociliary clearance and reduced vascular permeability.
54
What is the role of cAMP as a second messenger in β2 adrenoreceptor signaling?
Binding of the ligand to the β2 adrenoreceptor alters the receptor's conformation, exposing the binding site for the Gs protein. This leads to the activation of adenylyl cyclase, which produces many molecules of cAMP. cAMP serves as a second messenger that triggers downstream cellular responses.
55
Can you describe the process of β2 adrenoreceptor signaling?
Ligand binding changes the conformation of the receptor, allowing it to associate with the Gs protein.
The Gs protein, upon binding, releases GDP and binds to GTP, causing the α subunit to dissociate from the Gs complex.
The α subunit activates adenylyl cyclase, leading to the production of cAMP.
The ligand dissociates, returning the receptor to its original conformation.
Hydrolysis of GTP by the α subunit leads to its inactivation and dissociation from adenylyl cyclase, which becomes inactive as well. The α subunit then reassociates with the βγ complex to reform Gs.
56
What is Salbutamol?
albutamol is a short-acting bronchodilator and belongs to the class of short-acting β2 agonists (SABA).
57
How is Salbutamol administered for asthma and COPD symptom control?
Salbutamol is commonly administered via inhaler for symptom control in asthma and COPD. It helps alleviate breathlessness, chest tightness, and wheezing.
58
In what situations is Salbutamol given via a nebulizer?
Salbutamol is given via a nebulizer for the management of exacerbations of asthma and COPD.
59
What is the onset of action and duration of effect of Salbutamol?
Salbutamol typically has a rapid onset of action, usually within 10 minutes. The effects are short-acting, lasting for about 3-5 hours.
60
What are some side effects of Salbutamol?
Tachycardia (due to β receptors in the heart)
Tremor (due to β receptors in skeletal muscle)
Agitation
The side effects are dose-dependent, meaning they may occur more frequently with higher doses.
The intravenous route of Salbutamol administration is associated with more side effects compared to other routes.
61
What is a long-acting β-adrenoceptor agonist (LABA)?
A long-acting β-adrenoceptor agonist (LABA) is a type of medication used for the treatment of asthma and COPD. It provides long-lasting bronchodilation by stimulating the β2-adrenoceptors in the bronchial smooth muscle.
62
What is an example of a LABA?
Salmeterol is an example of a long-acting β-adrenoceptor agonist (LABA).
63
What is the onset and duration of action for salmeterol?
Salmeterol has an onset of action of approximately 30 minutes and a duration of action of 10-12 hours. It is administered via inhalation.
64
How is a LABA typically used in the treatment of asthma and COPD?
LABAs are typically used in combination with inhaled corticosteroids (ICS) and/or long-acting muscarinic antagonists (LAMA) for optimal control of airways in asthma and COPD. This combination approach helps suppress chronic inflammation, reduce airway hyperresponsiveness, and provide better symptom control.
65
What is the benefit of combining ICS and LAMA with a LABA?
Combining ICS and LAMA with a LABA provides complementary effects and optimal control of the airways. The combination helps in suppressing chronic inflammation, reducing airway hyperresponsiveness, and achieving better management of symptoms in asthma and COPD.
66
What is a short-acting muscarinic antagonist (SAMA)?
A short-acting muscarinic antagonist (SAMA) is a type of medication that blocks muscarinic receptors, inhibiting cholinergic nerve-induced bronchoconstriction and promoting bronchodilation.
67
How do SAMA drugs work in the airways?
In normal airways, there is a resting vagal bronchomotor tone caused by tonic cholinergic nerve impulses, which release acetylcholine (ACh) near the airway smooth muscle. SAMA drugs block muscarinic receptors and inhibit the cholinergic reflex bronchoconstriction, leading to bronchodilation.
68
When are SAMA drugs typically used?
SAMA drugs are primarily used in the management of acute exacerbations of asthma. They help alleviate bronchoconstriction and improve airflow during acute episodes.
69
What may trigger cholinergic reflex bronchoconstriction?
Cholinergic reflex bronchoconstriction can be initiated by irritants such as cold air and stress, leading to the constriction of the airways.
70
What are corticosteroids commonly used for in the treatment of lung disease?
Corticosteroids are the most commonly used drugs for the treatment of lung diseases, apart from antibiotics. They are potent anti-inflammatory drugs and have various systemic effects.
71
Where are glucocorticosteroid (GCS) receptors found in the body?
GCS receptors are found in most cells in the body.
72
How do corticosteroids exert their anti-inflammatory effects?
Corticosteroids are taken into cells and form a complex with GCS receptors. This complex binds to target genes and influences the transcription of inflammatory and anti-inflammatory components, thereby exerting their anti-inflammatory effects.
73
What are the different routes of administration for corticosteroids?
Oral: Prednisolone is a commonly used corticosteroid administered orally.
Inhaled corticosteroids: Beclomethasone is an example of an inhaled corticosteroid, which is delivered directly to the lungs.
Intravenous: Corticosteroids can be administered intravenously for certain indications.
Intranasal: Corticosteroids are also available in intranasal formulations for the treatment of nasal inflammation.
74
What are some short-term side effects of oral steroids?
Short-term side effects of oral steroids include indigestion, skin bruising, insomnia, and psychosis.
75
What are some medium-term side effects of oral steroids?
Medium-term side effects of oral steroids include gastric ulcers, skin bruising, insomnia, psychosis, and weight gain.
76
What are some long-term side effects of oral steroids?
Osteoporosis: Oral steroids can lead to thinning of the bones due to decreased calcium absorption and increased bone turnover.
Growth retardation in children: Prolonged use of oral steroids can impair normal growth in children.
Weight gain: Steroids can increase appetite, leading to weight gain.
Cushingoid appearance: Prolonged use of steroids can cause a moon face and central obesity due to excessive steroid effects.
Adrenal suppression: Long-term use of steroids can suppress the normal production of steroids by the adrenal glands.
Hypertension: Steroids can stimulate mineralocorticoid receptors, leading to sodium retention and increased blood volume, resulting in hypertension.
Diabetes: Steroids can make the liver less sensitive to insulin, leading to increased blood glucose levels.
77
What are the advantages of using systemic routes (IV or oral) for steroids?
The advantages of using systemic routes (IV or oral) for steroids include stronger effects due to higher doses being available, the action being unaffected by inspiratory effort or inhaler technique, and being a better route in cases of illness or emergencies.
78
What are the disadvantages of using systemic routes (IV or oral) for steroids?
The disadvantages of using systemic routes (IV or oral) for steroids include a higher risk of side effects, especially with long-term therapy. The systemic distribution of the drug can lead to more widespread effects throughout the body.
79
What are the advantages of using inhaled steroids?
The advantages of using inhaled steroids include localized action directly in the airways, resulting in targeted treatment for lung diseases. Inhaled steroids have fewer systemic side effects compared to systemic routes, although some absorption can still occur.
80
What are the disadvantages of using inhaled steroids?
One potential disadvantage of using inhaled steroids is that in certain lung diseases, the disease itself may prevent the penetration of the drug to the affected areas. Additionally, some individuals may experience local side effects such as throat irritation or oral fungal infections when using inhaled steroids.
81
What are the most effective preventer drugs for asthma in both adults and children?
Inhaled corticosteroids (ICS) are the most effective preventer drugs for asthma in both adults and children.
82
How often should ICS be prescribed for asthma?
ICS should be prescribed twice a day for optimal effectiveness in controlling asthma symptoms and reducing inflammation.
83
Which specific ICS is mentioned as a core drug?
Beclomethasone dipropionate (BDP) is mentioned as a core drug for asthma treatment.
84
What are some side effects of ICS?
Side effects of ICS include a reduced ability of the body to fight infections, which can lead to an increased risk of fungal infections such as oral candidiasis. Additionally, dysphonia (voice changes) may occur as a side effect of ICS use.
85
What advice should be given to individuals using ICS?
It is advised to gargle after using ICS to help minimize the risk of developing oral candidiasis. Using an ICS with a spacer for a pressurized metered-dose inhaler (pMDI) or a dry powder inhaler (DPI) is recommended for optimal delivery of the medication to the lungs.
86
What are the types of inhalers commonly used?
Pressurised metered dose inhalers (pMDI) used with a spacer/volumatic device. The drug is dissolved in a propellant hydrofluorocarbon (HFCs) under pressure, and a valve system releases a metered dose.
Dry powder inhalers (DPI) are activated by the patient's inspiration. The powdered drug is dispersed into particles during inhalation.
Soft mist inhalers (SMI) are another type of inhaler, although no additional information was provided about them.
87
What is the purpose of combination therapy in asthma and COPD?
Combination therapy, which involves using different drugs together, can increase efficacy as the drugs act synergistically. Combinations maximize bronchodilation, improve symptoms and quality of life, and reduce exacerbations in asthma and COPD. Adding a drug to an existing therapy, rather than increasing the dose of an existing therapy, may also help reduce the risk of adverse events.
88
What are some advantages of combination therapy?
Combinations of drugs in inhalers offer several advantages, including increased convenience, improved compliance (adherence to treatment), and cost-effectiveness.
89
What is the purpose of using a spacer device with aerosol inhalers?
A spacer device improves drug delivery and is recommended for use with all aerosol inhalers, including pressurised metered dose inhalers (pMDI). It increases the distance from the inhaler's actuator to the mouth, allowing particles to slow down and evaporate before inhalation. This results in a larger proportion of particles being deposited in the lungs and reduces drug deposition in the oropharynx, decreasing the incidence of oropharyngeal candidiasis.
90
What is a volumatic device and how does it work?
A volumatic device is a large spacer with a one-way valve. It further increases the distance from the inhaler's actuator to the mouth, allowing particles more time to evaporate and slow down before inhalation. This enhances drug deposition in the lungs and minimizes drug deposition in the oropharynx.
91
What is a nebuliser and how is it used?
A nebuliser is a device that turns a solution containing a drug into an aerosol for inhalation. It delivers a higher dose of the drug to the airways compared to an inhaler. Nebulised short-acting β-2 agonists (SABA) and anticholinergic medications are commonly used to treat patients with exacerbation of asthma or chronic obstructive pulmonary disease (COPD). Nebulised SABA can also be used to assess airway reversibility in patients with asthma and COPD.
92
What is the mechanism of action of theophylline?
Theophylline is a non-selective phosphodiesterase inhibitor. It has minimal effect on bronchomotor tone in normal airways but can reverse bronchoconstriction in asthmatic patients. It increases intracellular cAMP concentration and blocks adenosine receptors, leading to a decrease in bronchoconstriction. Theophylline is used in the treatment of asthma and chronic obstructive pulmonary disease (COPD).
93
What are some key management strategies for asthma?
The management of asthma includes several strategies:
Avoiding allergens that can trigger asthma symptoms.
Smoking cessation, as smoking worsens asthma symptoms.
Utilizing inhaled therapy, such as bronchodilators and corticosteroids.
Following a self-management plan that includes monitoring symptoms and using rescue medications as needed.
Regularly reviewing asthma treatment with a trained healthcare professional to assess compliance, inhaler technique, and prescription accuracy.
Following a stepwise approach, which involves adjusting asthma treatment up or down the treatment ladder based on the severity of symptoms.
94
What is the role of preventer inhalers in asthma management?
Preventer inhalers are used to reduce inflammation in the bronchi by blocking the inflammatory pathway. Inhaled corticosteroids (ICS) are the first-line treatment for asthma and are commonly used as preventers to control and prevent asthma symptoms.
95
How are preventers and relievers used in asthma treatment?
Preventer inhalers, such as inhaled corticosteroids (ICS), are used regularly to control asthma symptoms and reduce inflammation. They are taken every day to maintain long-term asthma control. On the other hand, reliever inhalers provide quick relief by causing bronchodilation of the airways for a few hours and improving symptoms. Short-acting β-2 agonists (SABA) are commonly used as relievers in asthma treatment.
96
What should be included in a self-management plan for asthma?
Daily medication: List the specific medications to take every day, such as inhaled corticosteroids (ICS), and explain their purpose in controlling asthma symptoms and reducing inflammation.
Asthma triggers to avoid: Identify common triggers, such as allergens or irritants, and emphasize the importance of avoiding them. Highlight the significance of a smoke-free environment.
Monitoring signs of deterioration: Explain the signs and symptoms of worsening asthma, such as increased breathlessness or wheezing, and provide the recommended peak expiratory flow rate (PEFR) values to monitor lung function.
97
How can a personalized asthma action plan be helpful?
A personalized asthma action plan (PAAP) provides clear instructions and guidance on managing asthma effectively. It typically uses a traffic light color-coding system:
Green: Indicates good control, where daily medication is taken as prescribed, triggers are avoided, and symptoms are minimal.
Yellow: Indicates caution, where symptoms may be worsening or PEFR values are decreasing. It advises stepping up medication or taking specific medications for worsening asthma.
Red: Indicates a medical emergency, where immediate medical attention is needed. It outlines the signs of severe asthma exacerbation and advises seeking urgent medical help.
98
What other aspects of asthma management should be considered?
Annual asthma review: Emphasize the importance of regular check-ups with a healthcare professional, typically in a GP surgery, to assess asthma control, review medication, and make any necessary adjustments.
Referral to secondary care: For poorly controlled patients, highlight the need for referral to a specialist or secondary care for further assessment and management.
99
What are some reasons for deaths related to asthma exacerbation?
Patient factors: Poor compliance with medication, failure to recognize severe symptoms, not seeking urgent medical help when needed.
Health professional factors: Lack of understanding of asthma, providing inappropriate advice, failure to recognize severe asthma symptoms.
Health system factors: Lack of resources, inadequate training in asthma management.
100
What are some key interventions in the management of acute asthma?
xygen administration (ABC approach): Ensuring adequate oxygenation.
High-dose nebulized β-2 agonist (e.g., salbutamol): Providing bronchodilation to relieve airway constriction.
Nebulized ipratropium bromide (Atrovent): Combined with β-2 agonist to enhance bronchodilation.
Systemic steroids: Administering corticosteroids (e.g., prednisolone or hydrocortisone) to reduce inflammation and mortality.
IV magnesium sulfate: Used as an adjunct treatment for severe asthma exacerbations.
Antibiotics: Prescribing antibiotics for bacterial chest infections, if present.
Aminophylline: Methylxanthine medication that can be administered intravenously to relax bronchial smooth muscle.
IV fluids: Maintaining hydration and supporting overall management.
ICU management: In severe cases, intubation and ventilation in an intensive care unit (ICU) may be necessary.
101
How can the risk of death from asthma exacerbation be minimized?
Minimizing the risk of death from asthma exacerbation involves a comprehensive approach:
Patient education and self-management: Ensuring patients understand their condition, recognize worsening symptoms, and know when to seek urgent help.
Healthcare professional training: Improving knowledge and understanding of asthma management among healthcare professionals.
Adequate resources: Ensuring healthcare facilities have the necessary resources and equipment for asthma management.
Access to appropriate care: Timely access to healthcare services and appropriate treatment options.
Regular review and follow-up: Regular check-ups to assess asthma control, adjust medications, and address any concerns.
102
What criteria should be met for the discharge of asthma patients after admission?
The following criteria should be met for the discharge of asthma patients after admission:
The patient should have stopped nebulized therapy and been on discharge medication for at least 24 hours prior to discharge.
Peak Expiratory Flow Rate (PEFR) should be greater than 75% of the best or predicted value.
PEFR diurnal variability should be less than 25%.
Inhaler technique should be checked and confirmed to be correct.
A Personalized Asthma Action Plan (PAAP) should be created and thoroughly understood by the patient.
Discussion about smoking cessation should take place, including the prescription of Nicotine Replacement Therapy (NRT) and referral to a Smoking Cessation clinic if necessary.
The dose of oral steroids should be gradually reduced, if applicable.
A follow-up review should be scheduled within 2 weeks, either with a nurse or doctor, to monitor the patient's progress and make any necessary adjustments to the treatment plan.
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What is the importance of checking inhaler technique before discharge?
Proper inhaler technique ensures that the patient receives the correct dose of medication.
Inadequate inhaler technique can lead to poor medication delivery to the lungs, resulting in suboptimal asthma control.
By confirming correct inhaler technique, healthcare professionals can ensure that patients are using their inhalers effectively and maximizing the benefits of their prescribed medications.
104
Why is it important to schedule a follow-up review within 2 weeks after discharge?
Scheduling a follow-up review within 2 weeks after discharge is important because:
It allows healthcare professionals to monitor the patient's progress and assess the effectiveness of the treatment plan.
Any necessary adjustments to medication dosages or treatment strategies can be made based on the patient's response and symptom control.
It provides an opportunity to address any questions or concerns the patient may have and reinforce asthma management strategies.
Regular follow-up helps ensure ongoing support for the patient, promotes adherence to the treatment plan, and reduces the risk of asthma exacerbations or readmissions.
