Chapt. 7: Asthma Flashcards
Common but complex clinical syndrome affecting people of all ages, characterized by variable airflow obstruction, bronchial hyperresponsiveness and airway inflammation, and manifesting as differing phenotypes.
Asthma
Burden of disease of asthma?
Affects 300million individuals of all ages worldwide, comprising 1-18% of the population in different countries
Are fundamental to the definition of asthma, but are rarely measured in primary care?
Airway inflammation and Bronchial Hyperresponsiveness
Used to demonstrate the presence and reversibility of airflow obstruction, and patient-held peak expiratory flow (PEF) meters can be used to show variable airflow obstruction over a period of time (eg. 2-4 weeks)
Spirometry
The principal mechanism of asthma and the main treatment target.
Airway inflammation
Typical features of airway inflammation in asthma?
Increased eosinophils, mast cells, and lymphocytes and predominance of type 2 helper T lymphocytes (Th2 cells).
What is produced by Th2 cells?
IL-3, IL-4, IL-5, IL-13 and GM-CSF
What phenotype of asthma exhibits only few inflammatory cells?
pauci-granulocytic phenotype
What characterizes asthma?
Structural changes in the airway that may precede the development of asthma, including epithelial damage, subepithelial fibrosis, increased airway vasculature, and increased smooth muscle mass.
Mucous hypersecretion is associated with what?
With an increase in the number of secretory glands and goblet cells
What is the prevalence of asthma?
3-5% in developing countries to >20% in developed countries, affecting people of all ages
Allergic type asthma is frequently accompanied by what other manifestations of allergy?
Allergic rhinitis and atopic dermatitis
Of asthma sufferers, what percentage of patients have their first episode of wheezing before 6 years of age?
95%
Adult onset asthma, which is more common in women, is associated with what? (3)
More persistent airflow obstruction, a lack of association with atopy, a worse prognosis.
Asthma common male or female?
Asthma is more common in boys than girls, but more common in women than men, the gender switch occurring in adolescence.
How many people die from asthma each year?
250000 deaths each year, accounting for 1 in every 250 deaths worldwide
What is the incidence of adult onset asthma?
4.6 cases per 1000 person-years in females and 3.6 in males
What is often used to define asthma?
Wheezing at any time in the previous 12 months
Chronic inflammation in asthma is accompanied by structural changes referred to as what?
Remodeling
At least what proportion of patients with asthma have features of allergy, consituting allergic or extrinsic asthma, usually accompanied by elevated levels of circulating IgE, and usually beginning in childhood?
Two thirds
What is the dominant abnormality in asthma?
Airway inflammation, occuring even in the earliest stages
What are the airway inflammatory cells?
Lymphocytes, plasma cells, mast cells and macrophages, typically associated with eosinophils.
What other cells are seen in asthmatic patients who are also smokers?
Neutrophils
What is exhibited by the cells in allergic asthma?
Th2 profile of cytoking secretion, characterized by production if IL-4, IL-5, IL-9, GM-CSF and IL-1
Structural alterations in the lungs are termed?
Airway remodeling. Characteristically involves airway wall thickening in large and small airways, involving all airway wall components. The epithelium is hyperplastic and injured.
Describe the basement membrane in asthmatic patients.
It is thickened by subepithelial fibrosis, with hyperplasia and hypertrophy of mucus-secreting cells. The airway walls have increased vascularity and smooth muscle hypertrophy or hyperplasia. Stiffness and loss of elasticity of the parenchyma occurs, contributing to air trapping and hyperinflation.
Identified as an asthma-susceptibility gene, with a polymorphism associated with early-life measures of lung function.
ADAM33
Refers to the relationship between genetic variation and drug response, with research focused on the B2-adrenoreceptor encoded by the gene ADRB2.
Pharmacogenetics
These processes result from modifications of DNA structure without a change in the sequence in response to environmental exposures, and may be passed between generations.
Epigenetic processes
Refers to the observable characteristics of an individual or group resulting from interaction of its genotype with its environment.
Phenotype
What defines the different phenotypes in asthma?
Clinical features
Pattern of inflammation
Pulmonary function
Triggers or on comorbidity
A subtype defined by distinct functional or pathophysiologic mechanisms, and addresses etiology and pathophysiology?
Endotype
What are some associated comorbidities with asthma?
Rhinitis, sinusitis, GERD, obstructive sleep apnea, hormonal disorders, and psychological disturbances.
Phenotypes of Asthma based on Airway inflammation (3)?
Eosinophilic
Neutrophilic
Pauci-granulocytic
What are the phenotypes of asthma based on clinical features? (5)
Mild, moderate, or severe asthma Exacerbation-prone Treatment-resistant Early-onset or late-onset asthma Asthma in the elderly
What are the phenotypes of asthma based on pulmonary function? (3)
With a component of fixed airway obstruction
With marked/rapid fluctuations of airway caliber
With marked hyperinflation
What are the phenotypes of asthma based on triggers? (7)
Allergic or non-allergic asthma Aspirin or NSAIDs Occupational allergens or irritants Hormones: premenstrual and menopausal asthma Exercise or cold air-induced asthma Asthma in high level athlete Asthma in the smoker
What are the phenotypes of asthma based on comorbid conditions? (5)
Rhinitis/rhinosinusitis, nasal polyps, and aspirin intolerance
Psychological disturbances (eg. depression, anxiety disorders)
With dysfunctional breathing (hyperventilation syndrome, vocal cord dysfunction)
With associated COPD
Asthma in the obese
What are the 4 wheezing phenotypes? (According to the Tucson Children’s Respiratory Study)
- Never (51%)
- Transient early (20%), with onset of wheezing before age 3 years and wheezing resolved by age 6
- Persistent (14%), with onset of wheezing before age 3 years with continued wheezing at age 6
- Late onset (15%), with onset of wheezing between 3 and 6 years of age.
Most prevalent type of wheezing?
Early transient wheezing
Of children who wheeze in the first 3 years, _____ have resolution of their symptoms by 6 years of age.
60%
Is transient wheezing associated with maternal smoking during pregnancy?
Yes.
What proportion of adolescents who are transient wheezers continue to wheeze?
Less than one quarter
What type of wheezing is associated with the first episode of wheezing occurring before the age of 1 year?
Non-atopic persistent wheezing, representing 20% of wheezy children under 3 years of age.
What are the pulmonary changes seen in children with non-atopic persistent wheezing?
Lower level of prebronchodilator lung function and enhanced airway reactivity.
In 20% of children who wheeze during the first 3 years, what are the findings?
IgE-associated atopic persistent wheezing.
What are the risk factors for wheezing?
Male gender, parental asthma, atopic dermatitis, eosinophilia at 9 months, and history of wheezing with infections.
What is the pattern of lung function in children with wheezing?
normal lung function in infancy but reduced lung function at age 6 years
What are the potential risk factors for the development of asthma?
Personal or family history of asthma and allergy
Exposure to airborne allergens
Tobacco smoke or other polluntants
Past respiratory infections
What are the PE findings in asthmatic patients during an exacerbation?
Wheezes heard with auscultation, with prolonged expiratory time.
Preferred method to measure airway obstruction in asthma.
Spirometry
Definition of airway obstruction during spirometry
A ratio of forced expiratory volume in 1 second (FEV1) to forced vital capacity (FVC) of <0.7
An absolute measure of the volume of air exhaled in the first second of forced expiration
FEV1
Indicates presence of airway obstruction.
Reduced percent predicted FEV1 with a low FEV1/FVC ratio
Definition of reversibility in asthma
An increase in FEV1 of 12% or more with at least a 200ml change after a bronchodilator or following 4 weeks of anti-inflammatory treatment with ICS
What is the lower limit of normal in spirometry?
5th percentile. because these values are not always proportional to the percent of predicted value.
What are most commonly used to predict normal values of spirometry?
Fixed-ratio lower limit of normal for FEV1/FVC (70%) and percent of predicted FEV1
How to diagnose asthma in adults?
Symptoms of episodic breathlessness, wheezing, cough, chest tightness, phlegm production (one or more)
PLUS
Increase in FEV1 after a bronchodilator or after a course of controlled therapy >=12% (and a minimum of >=200ml)
OR
Increase in PEF after a bronchodilator or after a course of controller therapy of 60L/min (minimum >=20%, based on multiple daily readings)
OR
Metacholine PC20 <4 mg/mL (4-16 mg/mL is borderline)
OR
Decrease in FEV1 after excercise challenge >=10-15%
FEV1: forced expiratory volume in 1 second; FVC forced vital capacity; PC20: provocative concentration that induces a 20% fall in FEV1; PEF: peak expiratory flow
What test can be used to demonstrate peak flow variability over a period of time (e.g. 2 weeks) to support the diagnosis of asthma?
Domiciliary morning and night monitoring
What is the classic monitoring pattern seen in untreated asthmatic patients?
“saw-tooth” pattern with significant diurnal variability (lower values on morning readings)
How to calculate for diurnal variability for asthmatic patients? (lower values on morning readings)
Highest PEF of the day minus the lowest PEF reading divided by the mean of the day’s highest and lowest readings, and averaged over a 1 to 2 week period.
What is the average diurnal variability?
> 10%, and the greater the variation, the greater the support for diagnosis
Provides an objective test of the constriction thresholds or ‘twitchiness’ of the airways.
Bronchial provocation test
How to perform bronchial provocation test?
Patients inhale (usually via a nebulizer) increasing concentrations or cumulative doses of a bronchoconstrictor, and spirometry is repeated until a 20% reduction in baseline FEV1 is observed. The lower the concentration or dose required, the more hyperreactive the airways. These are highly sensitive.
What is the most common bronchial challenge test?
Metacholine inhalational test. Measures the provocative concentration of metacholine inducing a 20% fall i FEV1 (PC20). Test is sensitive but not specific.
In what other conditions may metacholine inhalational test be positive?
Rhinitis
COPD
In what conditions may have a false-negative metacholine inhalational test?
Regular use of ICS
Although total IgE levels suggest an atopic status, they do not help to establish a diagnosis of asthma and are of limited clinical value. True or false?
True.
What are other non-invasive assessments of airway inflammation that are helpful in cases of diagnostic difficulty?
Induced sputum analysis
Measurement of fractional nitric oxide concentration in exhaled breath (FeNO).
What is upregulated in asthmatic inflammation?
Production of NO by airway epithelial cells which is driven by inducible NO synthase, and is upregulated in asthmatic inflammation, while production of iNOS is decreased by corticosteroid therapy.
What test may help to detect eosinophilic inflammation assess the likelihood of steroid responsiveness, contribute to the monitoring of corticosteroid needs, and detect non-adherence?
FeNO
Role of imaging studies in the diagnosis or follow-up of asthma?
Can be used to investigate diagnostic difficulties when they arise such as allergic bronchopulmonary aspergillosis, COPD (emphysema), and interstitial diseases.
Findings on HRCT in severe asthma patients
Lung hyperinflation
Mosaic perfusion pattern at full inspiration (reflecting ventilation-perfusion inequalities)
Increased airway wall thickness
What is work-related asthma?
Broad term indicating asthma worsened by the workplace. It encompasses “occupational asthma” anmd “work-exacerbated asthma”.
What is occupational asthma?
Asthma caused by a specific workplace agent
What is work-exacerbated asthma?
Asthma is worsened by stimuli at the workplace
Common citation of the definition of occupational asthma?
Characterized by airway inflammation, variable airflow limitation, and airway hyperresponsiveness due to causes and conditions attributable to a particular occupational environment and not to stimuli encountered outside the workplace.
What percentage of all cases of adult-onset asthma are attributable to workplace exposures?
17.6%
What are the common causes of adult-onset asthma?
Laboratory animals
Wheat flour
Dental health apprentices exposed to latex gloves
What is the pathophysiology in the majority of adult onset asthma?
IgE-dependent mechanism
What are some HMW agents which can cause adult-onset asthma?
Cereals (flour): wheat, rye, barley, buckwheat
Latex: gloves
Animals: mice, rats, cows, seafood
Enzymes: alpha-amylase, maxatase, alcalase, papain, bromelain, pancreatin
What are some LMW agents which can cause adult-onset asthma?
Isocyanates Metals Biocides Persulfate salts Acid anhydrides Reactive dyes Acrylates Wood dusts
Treatment of occupational asthma?
Early removal of sensitizing factor may allow full resolution.
How to confirm diagnosis of occupational asthma?
serial measures of airway responsiveness and PEF, or specific bronchoprovocation tests performed
What is the presentation of asthma in elderly patients?
May show mostly a combined neutrophilic and eosinophilic inflammatory pattern with more severe airway obstruction and physiologic features related to aging of the lung.
What are some conditions which may mimic asthma?
Vocal cord dysfunction Hyperventilation syndrome Upper airways diseases Deconditioning Obesity-related symptoms Pulmonary embolism OSA Airway neoplasms
Particularly in elderly patients, what conditions may manifest with asthma-like symptoms?
Smoking-induced COPD
Cardiac insufficiency
What are less common masqueraders of asthma?
Bronchiectasis
Vasculitis (Churg-Strauss syndrome)
Cystic fibrosis
Mastocytosis
What are the key symptom indicators for considering a diagnosis of asthma?
- Wheezing - high pitched wheezing sounds when breathing out (normal chest exam without wheezing does not exclude asthma)
- History of any of the following: cough (worse particularly at night), recurrent wheeze, recurrent difficulty breathing, recurrent chest tightness
- Symptoms occur or worsen in the presence of: exercise, viral infection, inhalant allergens, irritants, changes in weather, strong emotional expression, stress, menses
- Symptoms occur or worsen at night, waking the patient
What are the risk factors to the development of asthma?
Personal or family history of atopic disease.
What else should you document in an asthmatic patient?
Age of onset
Timing and pattern of qheezing
Relationship of episodes to viral illness and feeding
Comorbidities
Response to previous treatments
Socioenvironmental factors contributing to morbidity
What are alternative features suggesting an alternative diagnosis?
Symptoms starting at birth Continuous wheezing Failure to thrive Failure to respond to medications No association with typical triggers such as viral upper respiratory infections or exposure to allergens after sensitization.
What are some physical examinations that increase the probability of asthma?
(May be normal) Chest hyperinflation Use of accessory muscles Hunched shoulders Barrel chest Wheezing during normal breathing or forced expiration Rhinitis Dermatitis (Unilateral wheeze may indicate foreign body aspiration)
What age are pulmonary function tests possible?
Children over 6 years old
Is FEV1 normal in children with asthma?
Yes, it is normal, but FEV1/FVC decreases as asthma severity increases
Allows the measurement of lung volumes and airway mechanics (resistance, conductance, specific conductance)
Plethysmography
Are based on respiratory system resistance and reactance produced by a loudspeaker on the child’s respiratory system during quiet tidal breathing?
Impulse oscillometry (IOS) measurements
What is the percentage of children at high risk for the development of asthma who were sensitized to aeroallergen and/or food allergen by ages 2 and 3 years?
60%
How to determine the presence of allergen-specific IgE?
RAST or skin-prick testing
According to GINA, what is the definition of controlled asthma?
If there are no daytime symptoms, no limitations of activities, no nocturnal symptoms or awakenings, no need for reliever medication, normal or near-normal pulmonary function, and no exacerbations
What is the goal of therapy in asthma?
Maintain control with the least amount of medication
What are the assessments of control in asthma?
Well-controlled
Not well-controlled
Very poorly controlled
What are the parameters to assess the current clinical control (preferable over 4 weeks) of asthma?
Daytime symptoms Limitation of activities Nocturnal symptoms/awakening Need for reliever/rescue treatment Lung function (PEF or FEV1)
What are the features that are associated with increased risk of adverse events in the future?
Poor clinical control Frequent exacerbations in the past year Ever admission to critical care for asthma Low FEV1 Exposure to cigarette smoke High-dose medications
How to monitor disease activity in asthma
Monitor inflammatory biomarkers such as sputum eosinophils and FeNO.
What characterizes mild or intermittent asthma?
Minimal symptoms and near-optimal pulmonary function, usually requiring no more than infrequent use of a SABA.
What is the definition of mild persistent asthma? moderate? severe?
Requiring a low dose of ICS to achieve control.
Requiring a higher dose of ICS of additional medication
Requiring high ICS plus add-on medication with or without corticosteroids.
What are the two major domains within the scope of asthma?
Impairment and risk
What refers to the frequency and intensity of current symptoms?
Impairment, based on five factors: daytime symptoms, nighttime awakenings, SABA use for symptom control, interference with activity, and lung function
What encompasses the risk?
three elements: exacerbations, progressive loss of lung function, and side effects from medications
What is the definition of exacerbations?
The need for short courses of oral corticosteroids and/or emergency care.
What is a strong predictor for future exacerbations?
Exacerbation occurring in the recent past
What are potentially reversible risk factors increasing exacerbation risk?
Poor adherence with ICS medication
Overuse of SABA medication
At-risk behaviors such as smoking
Poor inhaler technique
What is a patient-centered dimension of asthma that may not correlate well with current control, pulmonary function or biomarkers, but reflects how the patient experiences asthma in their life?
Quality of life
What validated QoL questionnaire is ‘generic’ (ie measures the overall health status)?
SF36
EQ5D
What validated QoL questionnaire measures the specific impact of asthma?
Asthma QoL Questionnaire, which may help predict healthcare use and future exacerbations and to characterize the impact of disease on the individual
What measures of lung function should be used for monitoring control?
PEF
What should the PEF be compared to?
With the patient’s best value, and can be used for domiciliary monitoring.
Where are measurements of PEF most useful?
In labile, severe asthma pr when patients have difficulties in interpreting their respiratory symptoms
When may spirometry be repeated to demonstrate the development of fixed or deteriorating lung function, which may indicate an asthma-COPD overlap syndrome (ACOS)?
On an annual basis. This is especially useful in smokers or the development of airway remodeling and the possible need for more intensive treatment.
What is indicative of suboptimal control and the need for a review of maintenance therapy?
Requirement for rescue medication use on more than 2 days a week
Overuse of SABA is associated with increased risk of exacerbation, hospitalization, and mortality, true or false?
True
What are the 2 broad categories of non-adherence reasons?
Non-intentional
Intentional
What is a key factor in successful asthma care?
Effective self-management. All patients should have asthma education and the provision of a written personal asthma action plan. This should be reviews and reinforced annually and after every episode of loss of control.
What is another key factor in establishing a successful partnership between patient and clinician?
Involves education in self-management
What is involved in education in self-management?
Identification of the characteristics of the patient’s asthma
Education of what constitutes control
Review of medications, including their actions and use
Development of an action plan
What modifiable factor increases asthma severity and reduces response to ICS?
Active and passive cigarette smoke
What other co morbid conditions should be addressed in the treatment of asthma?
CRS
GERD
Obesity
Psychosocial issues
Is an increase in BMI associated with greater asthma morbidity and the need for multiple medications?
Yes
What is the likelihood for psychological problems in asthmatic patients?
Six times more common, and the outcomes of all varieties are associated with poor asthma control.
What are the 2 main categories of asthma treatment medications?
Quick relief
Long term control
What are the quick relief medications in asthma treatment?
Short acting B2 agonists
Anticholinergics
Systemic corticosteroids
What are the long-term medications in asthma treatment?
Corticosteroids-inhaled and systemic Long acting B2-agonists Leukotriene receptor antagonists Methylxanthine Cromolyn/nedocromil Anticholinergics Omalizumab
What are the agents of choice for acute relief of asthma symptoms?
The SABAs, albuterol (salbutamol), levalbuterol, and pirbuterol.
What is Ipratropium bromide?
Is a muscarinic cholinergic antagonist and is used asthma, primarily in patients who either intolerant of B2-agonists or are experiencing limited benefit from SABA use.
What is Tiotropium?
Is a long-acting anticholinergic agent used in COPD
Describe the anti-inflammatory actions of corticosteroids?
Broad-based and affect lymphocyte function, principally Th2 generation, and inflammatory cell migration and activation
What are the side effects of ICS?
Minimal long-term side effects in low to moderate doses
What is the MOA of LRTA? Some examples of these?
Monteleukast, Zafirlukast, Zileuton, inhibits 5-lipoxygenase pathway.
What are long-acting B2-agonists?
Salmeterol and formoteral. These improve airflow at least least 12 hours.
What is the only approved immunomodulator (anti-IgE) and is given as an injectable monoclonal antibody to bind IgE?
Omalizumab. This is recommended for px with severe asthma, in those with poor control, raised IgE, and evidence of allergen-specific IgE. It improves control and reduces asthma exacerbations.
Has modest bronchodilator activity, and its use in asthma is limited by toxicity and modest efficacy and the need for monitoring of serum theophylline levels?
The methylxanthine theophylline
What agents interfere with mast cell activation mechanisms to reduce inflammatory mediator release?
Cromolyn sodium and nedocromil sodium
What characterizes intermittent asthma?
Symptoms on less than 3 days per weeks; nighttime awakenings less than twice per month; use of SABA no more than 2 days per week; normal activity; normal lung function; exacerbation frequency of 0 to 1 per year
Are short-acting anticholinergic agents recommended in relieving symptoms?
Generally NOT recommended owing to a slower onset of action and less bronchodilation.
What is the frequency SABAs can be used?
Every 4 to 6 hours for 24 hours if needed (e.g. during a viral infection). If regular use more than 24 hours is needed, a short course of oral corticosteroids may be needed. If episodes requiring more frequent SABAs occur more often than every 6 weeks, consideration given to step-up treatment.
What characterizes mild persistent asthma?
Symptoms less than 3 days per week; nighttime awakenings 3 to 4 times per month; use of SABA on less than 3 days per week; no activity limitation; normal lung function between exacerbations (FEV1 of 80%; 0 to 1 exacerbation the preceding year)
What is the preferred treatment for mild persistent asthma?
Low dose daily ICS. Results in fewer symtpoms, decreased exacerbation risk, and improved lung function.
Has limited anti-inflammatory effects and a narrow therapeutic profile.
Theophylline
What characterizes moderate persistent asthma?
Daily symptoms; nighttime awakening more than once per week; need for daily SABA use; limitation in daily activity; and compromises in lung function (FEV1 >60% but <80%); an average of two exacerbations in the previous year
What are two recommendations for moderate persistent asthma?
Medium dose of ICS or combination therapy with low-dose ICS and a LABA. In GINA: low-dose ICS plus LABA
What is the SMART regimen recommended by GINA?
SMART stands for Single Maintenance and Reliever Therapy. Combination therapy of budesonide and formoterol can be used for both maintenance and rescue treatment. Not approved by the USFDA, but is used in other parts of the world.
What characterizes severe persistent asthma (Steps 4 to 6)?
Their impairment includes symptoms throughout the day; sleep disturbance; need for frequent daily SABA; activity limitations; and compromise in lung function (FEV1 <60% predicted). These patients also have frequent exacerbations.
What is the treatment for severe persistent asthma?
Medium-dose ICS in combination with LABA, especially in those with exacerbations, ED visits, or hospitalizations.
What are some side effects of high ICS doses?
Adrenal function may be suppressed and cataracts or osteoporosis may develop in some patients, although risks are far less than associated with systemic corticosteroids
What are the Steps 5 and 6 in severe persistent asthma?
Recommended to advance the ICS dose to higher doses. Addition of Omalizumab can be considered.
What are some of the effects of Omalizumab?
Decreases in exacerbations, hospitalizations, reduction in inhaled and oral corticosteroids without loss of control, and patients’ significant improvement in quality of life, although not lung function.
What else should be considered in Step 6 of asthma management?
OCS (oral corticosteroids) at lowest possible dose, with monitoring for adverse effects, while attempting to reduce dose once control is achieved.
What is the schedule for follow-up evaluation in asthma after initation or adjustment of treatment?
Every 2 to 6 weeks.
How long should asthma be controlled for step-down therapy to be considered?
3 months
The US EPR-3 guideline recommends consideration of allergen-specific immunotherapy for what groups of patients?
Patients at step 2 to 4. Immunotherapy may have a disease-modifuing effect through the enhancement of regulatory T cell activity, the production of blocking antibodies, or upregulation of regulatory T cells.
What are the vaccines recommended for asthmatic patients?
People with moderate or severe asthma should receive an annual influenze vaccine. Inactivated influenza vaccines are associated with fewer side effects and are safer to administer to adults and to children over the age of 3 years, including those with ‘difficult to control’ asthma
What food additives and preservatives may occasionally cause worsening of asthma?
Sulfites, tartrazine, and MSG. Confirmation requires referral and blinded oral challenges
A potentially life-threatening condition that can both mimic and complicate severe asthma?
Anaphylaxis
What is prompt treatment for anyphylaxis?
Epinephrine followed by systemic corticosteroids, with bronchodilators and circulatory support if required.
What are the 4 components in attaining and sustaining asthma control in children and infants?
- Assessment and monitoring
- Education
- Control of triggers (environmental and comorbid conditions)
- Pharmacologic therapy
What are the 4 categories of asthma in infants and children?
- Intermittent
- Mild persistent
- Moderate persistent
- Severe persistent
What are the control level categories?
Well-controlled
Not well-controlled
Poorly controlled
How are severity and control evaluated?
As impairment (current asthma symptoms and pulmonary function) and risk (exacerbations and side effects)
Is stress and depression associated with poorly-controlled asthma?
Yes
Is parental mental status a predictor of asthma morbidity, hospitalization, and poor adherence to therapy?
Yes
What is the first line prophylactic therapy in all pediatric age groups?
ICS. ICS decrease BHR, inflammation, attenuate late phase allergen reaction, lessen symptoms, and exacerbation risk, but are not disease modifying.
Is there a potential to decrease growth rates in using ICS in children?
Yes. It is a small risk of side effect which must be balanced against the ability of ICSs to improve impairment and risk with long-term use.
What are the LABAs approved for use in children?
Salmeterol delivered by MDI in children aged 12 years and older (dry powder inhalation, DPI) for those 4 years and older, Formoterol for children 5 years and older.
What are the properties of Salmeterol and its comparison with Albuterol?
Salmeterol delayed (10-15 minutes) onset of action but the duration of 12-18 hours vs 3-6 hours for albuterol.
Is the use of LABA as monotherapy contraindicated?
Yes
What combination therapy may permit reductions in ICS without worsening of control?
ICS-LABA combination in patients 12 years and older
What 2 LRTAs have been approved for use in children younger than 12 years of age in the USA?
Monteleukast (in those at least 1 year of age) and Zafirlukast (at 7 years of age and older)
What age may be given Cromolyn sodium in nebulized form?
Children older than 2 years of age
Effective as monotherapy for persistent asthma and has a steroid-sparing effect in children with moderate to severe persistent asthma?
Theophylline
What is the target level of theophylline monitoring when prescribing this drug?
5-15 ug/mL
What are the EPR-3 recommendations for Omalizumab?
Considered for adjunctive therapy in persons 12 years of age and older who have severe asthma (not FDA-approved for use in children younger than 12 years of age)
The only childhood treatment shown to potentially modify allergic sensitization and reduce allergic asthma in regard to specific exposures
SCIT
Recommendations for SCIT?
In patients with STABLE asthma sensitized to that particular allergen if clear association between symptoms and allergen exposure can be established
Highest prevalence of asthma attack is in what age range?
Children 5-17 years old
What are common precipitators of asthma ED visits?
URTI and environmental allergies
What are the risk factors for death from asthma?
Asthma History:
- Previous severe exacerbations (e.g. intubation or ICU admission for asthma)
- 2 or more hospitalizations for asthma in the past year
- 3 or more ED visits for asthma in the past year
- Hospitalization or ED visit for asthma in the past month
- Using more than 2 canisters of SABA a month
- Difficulty perceiving asthma symptoms or severity of exacerbations
- Other risk factors: lack of a written asthma action plan, sensitivity to Alternaria
Social History
- Low socioeconomic status or inner-city residence
- Illicit drug use
- Major psychosocial problems
Comorbid conditions
- Cardiovascular disease
- Other chronic lung disease
- Other psychiatric disease
What are the key elements in the history which need to be reviewed?
Details of the current exacerbation (e.g. time of onset, potential causes)
Severity of symptoms
Response to treatment
Current medications
Asthma history (number of previous unscheduled office visits, ED visits, and hospitalizations)
Other comorbid conditions (e.g. other pulmonary or cardiac diseases)
What are key elements of the inital PE?
Overall status
V/s including pulse oximetry
Chest findings
How to measure pulmonary function in asthmatic patients?
FEV1 is preferred, although serial PEF measurements can provide an estimate of severity and can be used to guide emergency management.
What is the percentage of predicted FEV1 or PEF cut-offs for asthma exacerbation severity?
40% for severe and 70% for mild episodes
What is the home management of asthma exacerbation?
Initial treatment begins with an increase in frequency of SABA use, usually 2 to 6 puffs, 20 minutes apart. Response to initial treatment is graded as good, incomplete, or poor, based on a reassessment of symptoms and airflow obstruction. Up to 2 treatments 20 minutes apart. With a good response, SABA can be used frequently over the next 24 to 48 hours, along with a short course of prednisone if appropriate.
What is the common suggested regimen for systemic corticosteroids?
0.5 to 1mg of prednisone/kg of body weight for 3 to 7 days
In home treatment for asthma, what constitutes “good response”?
- No wheezing or dyspnea (assess tachypnea in young children)
- PEF =>80% predicted or personal best
- Contact clinician for follow-up instructions and further management
- May continue inhaled SABA every 3-4 hours for 24-48 hours
- Consider short course of oral systemic corticosteroids
In home treatment for asthma, what constitutes “incomplete response”?
- Persistent wheezing and dyspnea (tachypnea)
- PEF 50-79%% predicted or personal best
- Add oral systemic CS
- Continue inhaled SABA
- Contact clinician urgently (this day) for further instruction
In home treatment for asthma, what constitutes “poor response”?
- Marked wheezing and dyspnea
- PEF 50-79%% predicted or personal best
- Add oral systemic CS
- Continue inhaled SABA
- If distress is severe and non-responsive to initial treatment, call your doctor and proceed to RD, consider ambulance transport
What is the goal of emergency care in asthma?
- Ensure adequate oxygenation
- Reverse the obstruction
- Initiate anti-inflammatory therapy
What is used for detection of actual or impending respiratory failure and to detect conditions complicating emergency management?
ABG testing.
Can use ECG to rule out cardiac ischemia, chest radiograph to rule out pneumonia
What is recommended for initial ED or inpatient treatment?
Supplemental oxygen, administered by nasal cannula or mask, to maintain an SaO2 of >=90% or >=95% in pregnant women and those with cardiac disease.
What is the role of inhaled anticholinergic agents Ipratropium bromide?
May add this to B2-agonist therapy in severe asthma exacerbations. Multiple doses of ipratropium bromide results in a clinically significant improvement in FEV1 and reduced the risk of hospitalization by 25%
What is the role of systemic corticosteroids in asthma exacerbations?
Early use (within 1 hour of the presentation) delivered by oral or IV routes continues to be the principal treatment choice.
What is the role of IV corticosteroids in asthma exacerbations?
Reserved for those who are too breathless to swallow, obtunded or intubated, or unable to tolerate oral medications
What is used in unresponsive acute asthma, with immediate bronchodilator and mild anti-inflammatory effects?
MgSO4
How to administer leukotriene modifiers in asthmatic exacerbations?
Intravenous monteleukast may be beneficial in cases of moderate to severe exacerbations, with significant improvement in FEV1 within 10mins of administration.
When does the oral formulation of monteleukast provide benefit?
90 mins after administration
What is the percentage of ED patients treated for acute asthma who will relapse within 2 weeks of discharge?
10-20%
What is the duration of oral corticosteroids appropriate for patients after discharge from an acute asthma episode?
Short period (5-7days)
Children younger than 5 years old require what route of nebulization?
Use of a mask with nebulizer treatment or with an MDI and valved spacer system for effective delivery of medication into the airways.
_________ but not doubling the dose of ICS at the first sign of worsening symptoms in patients already receiving ICS may prevent exacerbations requiring oral corticosteroids.
Quadrupling.
The INCREASED SABA use during an exacerbation should continue until what point?
Until the level of asthma symptom control and PEF values return to the patient’s baseline.
What is the office or ED management in children?
In mild to moderate exacerbation (FEV1 or PEF >=40%), initial therapy includes oxygen to keep oxygen saturations higher than 90% and up to three doses in the first hour of inhaled SABA delivered by either nebulization or MDI.
In severe exacerbations (FEV1 or PEF <40%), what is the therapy for office of ED management?
Prompt administration of oxygen, high-dosed inhaled SABA plus ipratropium every 20mins or continuously for the first hour, and oral corticosteroids.
When should hospitalization be considered in children with asthma exacerbation?
An incomplete response in symptoms or lung function (FEV1 or PEF of 40-69%) despite aggressive treatment. Also for infants with oxygen saturation <92% on room air.
In addition to acute management, what is another important aspect of management of asthmatic patients?
Preventing recurrence
The most common reason for suboptimal outcomes in asthma?
Poor adherence and poor inhaler technique
