Asthma Flashcards
1
Q
What is wheezing?
A
A musical, high-pitched, largely expiratory sound made through partially obstructed larger airways.
Most commonly caused by asthma in school-age children, but can also result from narrowing in the distal trachea and glottic closure.
2
Q
What characterizes asthma?
A
Variable, reversible obstruction of air flow that may improve spontaneously or with specific therapy.
It is associated with airway hyperreactivity and chronic airway inflammation.
3
Q
Define airway hyperreactivity.
A
The inherent tendency of the trachea and bronchi to narrow in response to various stimuli.
Stimuli can include allergens, nonspecific irritants, or infections.
4
Q
What are common features of asthma pathology?
A
Marked hyperinflation, smooth muscle hyperplasia, thickened basement membrane, and mucosal edema.
Eosinophilia and mucous plugs containing shed epithelial cells and inflammatory cells are also common.
5
Q
What causes airflow limitation in asthma?
A
A combination of obstructive processes: mucosal edema, bronchospasm, loss of alveolar tethering, and mucous plugging.
6
Q
What are common symptoms of asthma?
A
Intermittent wheezing, coughing, shortness of breath, and a feeling of chest tightness.
Symptoms often worsen at night or early morning and improve throughout the day.
7
Q
What is a significant predictor of asthma in adulthood?
A
Presence of allergic sensitization, female sex, and severe or persistent asthma in early childhood.
8
Q
What is a key indicator of airway obstruction in children with asthma?
A
Reduction of the FEV1/FVC ratio.
9
Q
True or False: Wheezing can only be elicited during acute asthma symptoms.
A
False.
Wheezing can sometimes be elicited with a forced expiratory maneuver even in stable conditions.
10
Q
What is the role of Th2 cytokines in asthma?
A
They recruit other leukocytes and perpetuate inflammation in the airways.
11
Q
What is the significance of mast cells in asthma?
A
Increased mast cell degranulation is often associated with more severe asthma.
12
Q
Fill in the blank: The thickened basement membrane in asthma is due to submucosal deposition of _______.
A
type IV collagen.
13
Q
What are common causes of asthma mortality?
A
Inadequate treatment, poor access to healthcare, and overreliance on β-adrenergic agonists.
14
Q
What tests are used to diagnose asthma?
A
Detailed medical history, physical examination, spirometry, and ancillary tests such as allergy skin tests and inhalation challenges.
15
Q
What is the role of β-adrenergic agonists in asthma treatment?
A
They help relieve bronchospasm but may contribute to lactic acidosis if overused.
16
Q
What is the relationship between asthma and respiratory infections?
A
Respiratory infections are a significant risk factor for asthma exacerbations.
17
Q
What is a common feature of hyperventilation syndrome?
A
Marked dyspnea despite normal air exchange on auscultation and absence of wheezing.
18
Q
What is the significance of digital clubbing in a child with suspected asthma?
A
Its presence suggests other conditions such as cystic fibrosis, not asthma.
19
Q
What is the typical respiratory examination finding in children with severe asthma?
A
Auscultation may reveal coarse crackles or unequal breath sounds.
20
Q
What is a possible differential diagnosis for asthma in adolescents?
A
Vocal cord dysfunction (VCD) or exercise-induced laryngomalacia.
21
Q
What is clinically significant congenital laryngomalacia?
A
A diagnosis related to airway obstruction in infancy
It is characterized by abnormal flaccidity of the laryngeal structures.
22
Q
What is a common pulmonary function test finding in patients with vocal cord dysfunction (VCD)?
A
Pronounced flattening of the inspiratory loop
This may indicate extrathoracic obstruction.
23
Q
What is the mid-vital capacity expiratory/inspiratory flow ratio indicative of extrathoracic obstruction in VCD?
A
Greater than 2
Normal value is about 0.9.
24
Q
How is the diagnosis of vocal cord dysfunction confirmed?
A
By direct observation of paradoxical vocal cord movement via flexible laryngoscopy during an acute episode.
25
What should be considered in patients with atypical reports of wheeze or stridor?
Upper and lower airway examination with a flexible bronchoscope
## Footnote
This helps identify anatomic lesions.
26
What are common allergens that can induce asthma symptoms?
* Animal allergens
* Mold spores
* Pollens
* Insects (e.g., cockroach)
* Infectious agents (e.g., Mycoplasma)
* Drugs and foods
27
What are early antigen responses in asthma?
Bronchoconstrictor responses to allergens that occur within minutes of exposure.
28
What is the late asthmatic response?
Occurs 4–24 hours after antigen contact, resulting in more severe and protracted symptoms.
29
What inflammatory mediators are involved in the late asthmatic response?
* IL-4
* IL-5
* IL-13
30
What are some irritants that can trigger asthma?
* Paint odors
* Hairsprays
* Perfumes
* Chemicals
* Air pollutants
* Tobacco smoke
* Cold air
* Cold water
31
How can weather changes affect asthma?
They can increase asthmatic activity due to alterations in allergen or irritant content.
32
What viral respiratory pathogen is most commonly associated with asthma exacerbations?
Rhinovirus
## Footnote
Up to 85% of asthma exacerbations in school-aged children are due to viral infections.
33
What is exercise-induced bronchospasm (EIB)?
Bronchial obstruction triggered by strenuous exercise in individuals with persistent asthma.
34
What is the typical onset time for symptoms of exercise-induced asthma?
Symptoms typically begin after 5–10 minutes of vigorous activity.
35
What emotional factors can trigger asthma?
Emotional upsets and psychosocial stressors
## Footnote
They can modulate immune responses or decrease steroid responsiveness.
36
What is the relationship between gastroesophageal reflux (GER) and asthma?
GER can aggravate asthma, especially nocturnal asthma, even when typical symptoms are absent.
37
What role does allergic rhinitis and sinusitis play in asthma?
They can aggravate asthma and lead to less responsiveness to bronchodilator therapy.
38
What substances can exacerbate asthma in sensitive individuals?
* Aspirin
* Nonsteroidal anti-inflammatory drugs (NSAIDs)
* Metabisulfite
39
What endocrine factors can affect asthma in women?
Menstrual cycle fluctuations may aggravate asthma symptoms.
40
What is the significance of vitamin D in asthma management?
Lower vitamin D levels are associated with increased asthma morbidity and lower lung function.
41
What is nocturnal asthma?
A condition where asthma symptoms worsen at night, often linked to circadian variations.
42
What is the primary measure used to assess response in bronchial challenge tests?
FEV1 (forced expiratory volume in one second).
43
What is a positive test result in a methacholine challenge test?
A PC20 of ≤ 4 mg/mL indicates airway hyperreactivity.
44
What is the recommended procedure if baseline FEV1 is low before a bronchoprovocation test?
The test should not be performed.
45
What are potential mild adverse effects of bronchoprovocation tests?
* Cough
* Wheezing
* Chest tightness
* Dizziness
46
What factors must be interpreted when assessing asthma?
Degree of baseline obstruction, pretest probability of asthma, presence of current symptoms, degree of recovery in postchallenge FEV1
## Footnote
These factors are crucial for evaluating asthma severity and response to treatments.
47
What are mild transient adverse effects of bronchoprovocation tests?
Cough, wheezing, chest tightness, dizziness
## Footnote
These effects are uncommon and typically resolve quickly.
48
When should methacholine bronchoprovocation tests be avoided?
If the baseline FEV1 is low (generally less than 60% predicted)
## Footnote
This is to prevent severe reactions in individuals with significant airway obstruction.
49
What do indirect bronchoprovocation agents do?
Induce release of inflammatory mediators in the airway, causing bronchoconstriction
## Footnote
Examples include hypertonic saline, adenosine monophosphate (AMP), and mannitol.
50
What is the significance of a 15% decrease in FEV1 from baseline?
It had a specificity of 98% but a sensitivity of only 58%
## Footnote
This indicates a strong ability to identify asthma but a weaker ability to detect all cases.
51
What is the purpose of an exercise challenge test in asthmatics?
To provide useful information about the presence of exercise-induced bronchoconstriction (EIB) or exercise-induced asthma (EIA)
## Footnote
This test is particularly useful for children with histories suggestive of EIB.
52
How long should pulmonary function be measured after exercise in an exercise challenge test?
For at least 20 minutes (at 5, 10, and 20 minutes postexercise)
## Footnote
This helps determine the presence and severity of EIA.
53
What does a decrease in FEV1 of more than 10% indicate?
It is diagnostic of exercise-induced bronchoconstriction
## Footnote
Some sources suggest a threshold of 15% decrease.
54
What role does eosinophilia play in asthma?
It most commonly suggests asthma, allergy, or both
## Footnote
Elevated blood eosinophil counts are associated with atopic asthma.
55
What is the significance of induced sputum analysis in asthma?
Helps identify active inflammation in the airways
## Footnote
The presence and number of eosinophils and other inflammatory cells provide useful information about disease phenotype and response to therapy.
56
What is fractional exhaled nitric oxide (FeNO) used for?
A biomarker useful in asthma diagnosis, monitoring control, adjusting treatment, and predicting exacerbations
## Footnote
FeNO is correlated with eosinophilic airway inflammation.
57
What are the strengths and weaknesses of FeNO monitoring?
Strengths: correlates with eosinophilic inflammation. Weaknesses: poor ability to identify noneosinophilic inflammation and lack of specificity
## Footnote
Elevated FeNO can also occur in other conditions like allergic rhinitis and COPD.
58
What is the purpose of a serum test in asthma diagnosis?
To rule out immunodeficiency syndromes in children with recurrent or chronic infection
## Footnote
Total serum IgE is often elevated in children with asthma.
59
What is the sweat test used for?
To rule out cystic fibrosis in children with chronic respiratory symptoms
## Footnote
Symptoms prompting the test include poor weight gain, nasal polyps, and digital clubbing.
60
Why should children with suspected asthma have a chest radiograph?
To rule out parenchymal disease, congenital anomalies, and evidence of foreign bodies
## Footnote
A normal chest radiograph does not rule out other diagnoses.
61
What factors affect skin test results in allergy testing?
Age, drug therapy, inherent skin factors
## Footnote
H1 antihistamines can inhibit skin reactions for up to 72 hours.
62
What does asthma severity refer to?
The intrinsic intensity of the disease and the level of treatment necessary to achieve control
## Footnote
It is typically assigned prior to treatment and reassessed periodically.
63
What is the difference between asthma impairment and risk domains?
Impairment: daytime/nighttime symptoms, activity limitations, need for rescue medication. Risk: preventing severe exacerbations and adverse effects from medications
## Footnote
Both domains are essential for assessing asthma control.
64
What are short-acting β agonists (SABAs) used for?
Relief of bronchospasm and symptoms of asthma
## Footnote
They are potent bronchodilators with rapid onset of action.
65
What are the typical adverse effects of SABAs?
Muscular tremor, tachycardia, irritability
## Footnote
High doses can lead to hypokalemia and hypertension.
66
What is the role of ipratropium bromide in asthma treatment?
An anticholinergic agent that produces bronchodilatation by antagonizing acetylcholine receptors
## Footnote
It works particularly well when combined with β-adrenergic agonists.
67
Why are inhaled corticosteroids considered the most effective controller medication for asthma?
They have high topical potency and low systemic effects
## Footnote
They are absorbed through the respiratory epithelium with minimal systemic absorption.
68
What properties should an inhaled corticosteroid have?
* High affinity for glucocorticoid receptor
* Prolonged retention in the lung
* High serum protein binding
* Minimal oral bioavailability
* Rapid systemic inactivation
## Footnote
These properties increase therapeutic efficacy and reduce systemic side effects.
69
What are the key properties that confer a higher therapeutic index for certain corticosteroids?
The key properties include:
* Prolonged retention in the lung
* High level of serum protein binding
* High volume of distribution
* Minimal or no oral bioavailability
* Rapid, complete systemic inactivation
## Footnote
These properties lead to prolonged antiinflammatory activity in the lung with relatively few systemic adverse effects.
70
What is fluticasone propionate (FP) and its characteristics?
Fluticasone propionate is a potent, poorly orally absorbed corticosteroid that:
* Is extensively metabolized in the liver
* Has a high affinity for lung glucocorticoid receptors
* Shows negligible oral bioavailability
* Has a favorable topical-to-systemic activity ratio
## Footnote
FP is more likely to cause sore throat and hoarseness compared to other inhaled corticosteroids (ICSs).
71
What is the recommended maximum daily dose of fluticasone propionate for children younger than 12 years?
The maximum recommended dose is 400 μg/day.
## Footnote
Reports of adrenal suppression in this age group are inconsistent.
72
How does fluticasone furoate differ from fluticasone propionate?
Fluticasone furoate has:
* An extended half-life
* Once daily dosing
* Available in doses of 100 μg or 200 μg
## Footnote
It is approved for children and adolescents aged 12 years and older.
73
What are the key characteristics of budesonide (BUD)?
Budesonide has:
* Moderate potency in vitro and in vivo
* A free C21 hydroxy group that forms esters with long-chain fatty acids
* An inactive depot within airway epithelial cells
## Footnote
BUD is approved for use in children 1 year of age and older.
74
What is beclomethasone and how does it compare to fluticasone propionate and budesonide?
Beclomethasone is:
* Less potent than fluticasone propionate and slightly less so than budesonide
* Readily absorbed from the gastrointestinal tract
* Metabolized to a more potent monopropionate
## Footnote
Beclomethasone has a less favorable topical-to-systemic potency ratio.
75
What are the characteristics of mometasone?
Mometasone is:
* A potent, highly topically active steroid
* Effective in improving lung function in children with asthma
* Similar to fluticasone propionate in receptor affinity and half-life
## Footnote
It is approved for use in children 4 years of age and older.
76
What is ciclesonide and how does it function?
Ciclesonide is a prodrug that:
* Must be metabolized to its active form in the lung
* Has low oral bioavailability
* Is converted into its active metabolite, des-ciclesonide, in airway epithelial cells
## Footnote
Ciclesonide is approved for use in children 12 years of age and older.
77
What is the mechanism of action of corticosteroids?
Corticosteroids act by:
* Diffusing across the cell membrane
* Binding to glucocorticoid receptors
* Translocating to the nucleus to bind to glucocorticoid response elements
## Footnote
This process leads to suppression of inflammation and modulation of gene transcription.
78
What are the common local adverse effects of inhaled corticosteroids?
Common local adverse effects include:
* Oral candidiasis
* Dysphonia
## Footnote
These effects are dose-related and occur in a small minority of patients.
79
What are the potential serious systemic adverse effects of inhaled corticosteroids in children?
Serious systemic adverse effects include:
* Adrenal suppression
* Depression of linear growth
## Footnote
Most growth velocity decreases occur within the first few months of treatment.
80
What are the characteristics of long-acting β agonists (LABAs)?
LABAs have:
* Prolonged duration of action (8–24 hours)
* Available options include salmeterol and formoterol
* Differences in structure, potency, and efficacy
## Footnote
Salmeterol is approved for patients 4 years and older, while formoterol is approved for patients 12 years and older.
81
What is the role of LABAs in asthma treatment?
LABAs:
* Are not considered anti-inflammatory agents
* Should not be used as monotherapy for chronic asthma
* Can enhance the actions of inhaled corticosteroids
## Footnote
The FDA recommends LABAs be used in combination with other controller medications.
82
What can lead to reduced effectiveness of LABAs over time?
Reduced effectiveness may occur due to:
* Downregulation of beta-receptor number
* Lack of receptor sensitivity
## Footnote
This tolerance can affect the bronchoprotective effect.
83
What is the recommended approach for using LABAs with inhaled corticosteroids?
The recommended approach is:
* LABAs should be combined with inhaled corticosteroids
* LABAs should not replace inhaled corticosteroids
* LABAs should be discontinued once asthma control is achieved
## Footnote
This strategy helps improve asthma control without increasing steroid doses.
84
What is the effect of adding a LABA to ICS in pediatric patients?
It allowed a 37%–60% reduction in inhaled steroid dose without loss of asthma control
## Footnote
Higher doses of ICS may cause growth suppression.
85
What improvement was observed in children using the salmeterol plus fluticasone combination?
Significantly greater improvement in morning PEFR and a longer duration of asthma control (~1 week longer)
## Footnote
This improvement favors the combination therapy.
86
What did recent meta-analyses show about the safety of ICS and LABA combinations?
There is no increased risk for adverse asthma-related events compared to inhaled steroid alone.
87
What is salmeterol's role as a β receptor agonist?
It is a partial agonist, resulting in a flatter dose response curve and weaker protective effect against airway reactivity.
88
What was the effect of the maintenance plus reliever group on oral corticosteroids?
Significantly reduced overall exposure to oral corticosteroids and exacerbations requiring medical attention.
89
What are leukotrienes?
Lipid mediators produced by the metabolism of arachidonic acid via a cascade including phospholipase A2.
90
What role do cysteinyl leukotrienes (cysLTs) play in asthma?
They induce smooth muscle constriction, vascular permeability, mucus hypersecretion, edema formation, and inflammatory cell recruitment.
91
What are the two strategies targeting cysLTs?
* Inhibition of 5-lipoxygenase * Leukotriene receptor antagonism
92
What is the mechanism of zileuton?
It blocks the bronchoconstriction response to inhaled allergen, cold air challenge, exercise, and aspirin ingestion.
93
What is a significant side effect of zileuton?
It can cause hepatic injury, requiring regular liver enzyme monitoring.
94
What is Montelukast?
A LTD4 receptor antagonist administered once daily.
95
What are the clinical effects of Montelukast?
* Improvement in FEV1 * Protection from EIB and allergen-induced bronchospasm
96
How does Montelukast compare to ICS in terms of asthma control?
The effect on asthma control is not as great as that from an ICS.
97
What are common adverse effects of Montelukast?
* Headache * Abdominal pain * Vivid dreams * Sleep disruption
98
What is tiotropium?
A long-acting muscarinic receptor antagonist approved for severe persistent asthma.
99
What is the duration of action for tiotropium?
24 hours.
100
What is the effect of tiotropium when added to ICS or ICS and LABA?
It improves lung function and maintains improvement even after ICS dose reduction.
101
What is theophylline classified as?
A second- or third-line medication for asthma management.
102
What is the therapeutic effect of low-dose theophylline?
May help in chronic management of asthma.
103
What is a potential benefit of adding theophylline to ICS?
May have a steroid-sparing effect.
104
What are the risks associated with theophylline?
* Narrow therapeutic index * Significant adverse effects
105
What is omalizumab?
A humanized monoclonal anti-IgE antibody used in select asthma patients.
106
What is mepolizumab?
A monoclonal antibody to IL-5 for severe eosinophilic asthma.
107
What are the main goals of chronic asthma management?
* Identification and elimination of exacerbating factors * Pharmacologic therapy * Education of the patient and family
108
What does asthma control focus on?
Minimizing impairment and avoiding serious exacerbations.
109
What is the significance of annual lung function monitoring in children with asthma?
Recommended for all levels of asthma severity.
110
What is the purpose of holding chambers and spacer devices in asthma treatment?
To ensure maximum medication delivery to the lungs.
111
What are the three zones defined for PEFR monitoring?
* Green: 80%–100% predicted * Yellow: 50%–80% predicted * Red: <50% predicted
112
What are nonpharmacologic measures in asthma management?
* Frequent monitoring of symptoms * Trigger avoidance * Environmental control
113
What is the recommended treatment for mild acute asthma?
Inhaled SABA, most commonly albuterol.
114
What is the recommended dose of albuterol for acute asthma management?
2–6 puffs (90 μg/puff) every 20 minutes for 1 hour
## Footnote
Use a VHC if necessary
115
What indicates that symptoms have resolved after albuterol administration?
PEFR improves and the patient remains well for 3–4 hours
116
Is doubling the dose of inhaled steroids recommended at the onset of an exacerbation?
No, it is no longer recommended due to lack of clear benefit
117
What is appropriate for a steroid-naïve patient during an acute episode?
Initiating ICSs as a chronic treatment
118
What should be done if symptoms persist after albuterol administration?
Repeat albuterol dose and administer oral steroid (1–2 mg/kg, max 60 mg prednisone)
119
In what situation should a physician be contacted during asthma management?
If symptoms persist and PEFR improves little after albuterol
120
What is recommended for patients with progressive symptoms despite treatment?
Seek care in a medical facility
121
What is the dosing of nebulized albuterol in the emergency department?
2.5–5.0 mg or 4–6 puffs every 20 minutes for another hour
122
What is the benefit of IV steroids in acute asthma management?
There is no benefit unless the patient cannot tolerate oral form
123
What additional medication should be given every 20–30 minutes to patients with severe exacerbations?
Ipratropium (250 or 500 μg) by nebulizer
124
What is heliox and its role in asthma management?
A mixture of helium (80%) and oxygen (20%) that decreases airway resistance
125
What is the recommended dose of magnesium sulfate for severe asthma?
40–75 mg/kg (max 2 g) over a 20-minute period
126
What are the adverse events associated with magnesium sulfate?
Flushing, headache, decreased blood pressure, and weakness
127
What does montelukast not improve during status asthmaticus?
Symptoms, pulmonary function, or need for hospital admission
128
What is the threshold for oxygen saturation indicating hospital admission?
Persistent hypoxemia (O2 saturation < 92% while breathing room air)
129
What is the initial treatment for status asthmaticus in the hospital?
Humidified oxygen to maintain SaO2 > 93%
130
What should be monitored for patients in intensive care with severe asthma?
Development of respiratory failure
131
What should be considered if a patient does not improve after 12 hours of treatment?
Search for complicating factors and impending respiratory failure
132
What is the starting dose of terbutaline for IV administration?
5 μg/kg, followed by a continuous infusion of 0.4 μg/kg per minute
133
What should be monitored during mechanical ventilation of asthmatic patients?
Cardiac isoenzymes and continuous ECG
134
What are the indications for intubation in asthmatic patients?
Apnea, unstable vital signs, impaired consciousness, severe acidosis, extreme fatigue
135
What is the recommended ventilator strategy for asthmatic patients?
Volume ventilation with low tidal volumes and prolonged expiratory time
136
What pH level can be tolerated in asthmatic patients during ventilation?
As low as 7.2 if metabolic acidosis is not present
137
What should be done for aerosolized bronchodilators during mechanical ventilation?
Continue delivery through the endotracheal tube using an MDI and spacer
138
What is the maximum dose of methylprednisolone for asthmatic patients?
1–2 mg/kg (maximum 125 mg) every 24 hours
139
What adjunct treatment can be considered for the intubated asthmatic patient?
Ketamine infusions for sedation and bronchodilation
140
What is a potential adverse effect of ketamine in older children?
Psychoactive effects
