Category II - Bronchial Asthma Flashcards
True or false
Some cases of asthma may have an element of IRREVERSIBLE airflow obstruction.
TRUE.
Asthma is characterized by mostly reversible narrowing, however, chronic asthma may have an element of IRREVERSIBLE airflow obstruction.
It is the major risk factor for asthma
ATOPY
Due to a genetically determined production of specific IgE ab thus strong family history of allergic diseases is a risk factor
It is an INDEPENDENT risk factor for asthma, especially in women, but mechanisms are unknown
OBESITY (especially with BMI >30 kg/m2)
Consumption of this medication has an association with development of asthma, although mechanism remains unexplained
Acetaminophen (Paracetamol)
Most common allergen in asthma
House dust mites (Dermatophagoides sp)
Others: Cat and dog fur Cockroaches Grass and tree pollens Rodents
TRUE OR FALSE
All beta blockers have to be avoided including selective beta 1 blockers and topical eye drops
TRUE
Mechanism that would explain premenstrual worsening of asthma that can be severe in some women
Fall in progesterone levels
Choose:
In allergic type of asthma, there are high levels of IgE in airways.
FALSE
Allergic asthma:
(+) personal/FHx, atopic asthma, high levels of IgE in the SERUM
Idiosyncratic/Intrinsic asthma:
Adult asthma, (-) personal.FHx, non-atopic,
Normal IgE levels in serum, high IgE in AIRWAYS
What is the physiologic abnormality in asthma?
Airway hyperresponsiveness
TRUE or FALSE
Pathology of asthma is UNIFORM regardless of type (atopic, nonatopic, occupational, aspirin sensitive, pediatric)
True
TRUE or FALSE
In asthma, inflammation of the respiratory mucosa extends from the trachea to the lung parenchyma.
FALSE
In asthma, inflammation of the respiratory mucosa extends from the trachea to the terminal bronchioles.
Predominance of inflammation is at the BRONCHI (cartilaginous airways).
It is a characteristic feature of asthmatic airways
Eosinophilic infiltration
Eosinophils may be more important in release of growth factors involved in airway remodeling and in exacerbations BUT NOT in airway hyperresponsiveness.
These cells are increased in number in severe asthma/exacerbations BUT unknown role in asthma resistant to corticosteroids.
Neutrophils
These cells coordinate inflammatory response in asthma through the release of specific patterns of cytokines that recruit and maintain eosinophils and mast cell population in the airways.
T lymphocytes
Asthmatics have predominance of ______ phenotype.
TH1 or TH2?
TH2. TH2 cells or cytokines (IL-4, IL-5, IL-13) mediate allergic inflammation
In Normal airways, TH1 cells predominate
The cells are probably the major target cells for Inhaled corticosteroids in asthma.
Epithelial cells.
Epithelial cells translate inhaled environmental signals into an airway inflammatory response.
Production of _______ by inactivated inflammatory cells, related to disease severity, may amplify inflammatory response, reducing responsiveness of asthmatics to corticosteroids.
Reactive oxygen species (Oxidative stress)
What are the structural changes in the airways of asthmatics that may lead to IRREVERSIBLE narrowing?
Increased airway smooth muscle
Fibrosis
Angiogenesis
Mucus hyperplasia
V/Q mismatch in severe asthma? High or low?
LOW
More severe asthma: Decreased ventilation + increased pulmonary blood flow = V/Q mismatch and bronchial hyperemia
This confirms airflow limitation with decreased FEV1/FVC ratio and PEF in asthma
Spirometry
How do you define reversibility of airflow obstruction in spirometry?
Reversibility: >12% or 200ml increase in FEV1 15 min after an inhaled SABA or, in some, by a 2-4 week trial of oral glucocorticoids.
Usual Chest Xray finding among asthmatic patients.
NORMAL.
But may show hyperinflated lungs in more severe patients.
Aim/s of asthma therapy.
A. Minimal (ideally no) chronic symptoms, including nocturnal
B. Minimal (infrequent) exacerbations
C. Peak expiratory flow circadian variation <20%
D. No limitations on activities, including exercise
E. All of the above
E.
PLUS
No emergency visits
Minimal (ideally no) use of a required B agonist
(Near) normal peak expiratory flow
Minimal (or no) adverse effects from medicine
Drugs in asthma to induce rapid relief of symptoms mainly through relaxation of airway smooth muscle.
Bronchodilators (relievers)
- Beta agonists
- Anti-cholinergics
- Theophylline
Drugs in asthma that inhibit the underlying inflammatory process to reduce frequency, severity of subsequent exacerbations
Controllers.
- ICS
- Systemic CS
- Antileukotrienes
- Cromones
- Immunomodulators
- Anti-IgE (Omalizumab)
The most effective bronchodilators in asthma
Beta agonists
Increase intracellular cAMP –> smooth ms relaxation + inhibition of mast cells
SABA - duration 3-6 hours
LABA - duration 12 hours, may replace use of SABAs but NEVER given in the absence of ICS therapy as they do not control the underlying inflammation
LABA+ICS - improve asthma control and reduce exacerbations
Less effective bronchodilators and are used only as add on treatment in pxs with asthma that is not controlled by LABA+ICS
Anticholinergics (Ipratropium bromide, Tiotropium)
This medication for asthma inhibit phosphodiesterase, may have anti-inflammatory effect at lower doses, and may reduce corticosteroid insensitivity in severe asthma.
Theophylline
The most effective CONTROLLERS and anti-inflammatory agents for asthma
Inhaled corticosteroids
They are also the first line therapy for pxs with PERSISTENT asthma
What drugs for asthma block cys-LT1 receptors and provide modest clinical benefit in asthma
Antileukotrienes (Montelukast, Zafirlukast)
Medication for asthma that inhibit mast cell and sensory nerve activation thus effective in blocking trigger-induced asthma, such as exercise induced asthma.
Cromones (Cromolyn sodium, Nedocromil sodium)
What is the level of asthma control of a patient with 1 daytime symptom per week and nocturnal symptoms?
Partly controlled asthma (any measure presented)
- Daytime sx
Controlled (None or <=2 per week)
Partly controlled (>2/week) - Limitation of activities.
Controlled: None, Partly controlled: Any - Nocturnal sx/awakening
Controlled: None, Partly controlled: Any - Need for reliever/rescue inhaler
Controlled (None or <=2 per week)
Partly controlled (>2/week) - Lung function (PEF or FEV1)
Controlled: Normal
Partly controlled: <80% predicted or personal best
UNCONTROLLED: >=3 features of partly controlled
This diagnostic/laboratory finding may indicate impending respiratory failure among patients with acute severe asthma
Normal or rising PaCO2 levels
The most common reason for refractory asthma
Noncompliance to medication (particularly with ICS therapy)
Type of asthma where there are chaotic variations in lung function despite taking appropriate therapy
Brittle asthma
Most effective tx: SC epinephrine
Drugs in asthma therapy that are proven safe in pregnancy and without teratogenic potential (3)
- SABA
- ICS
- Theophylline
Breastfeeding not contraindicated when px is using these drugs.
Among pregnant pxs with asthma needing oral cortocosteroids, it is better to use _______ as it cannot be converted to its active metabolite by the fetal liver, thus protecting the fetus from systemic effects of the CS.
Prednisone
Among pregnant pxs with asthma needing oral cortocosteroids, it is better to use PREDNISONE rather than Prednisolone as it cannot be converted to its active metabolite by the fetal liver, thus protecting the fetus from systemic effects of the CS.
