Flashcards in Asthma Deck (67)
A chronic inflammatory disorder of the airways. Variable and recurring symptoms. Airflow obstruction. Bronchial hyperresponsiveness. Underlying inflammation
Pathophysiology of air flow obstruction
airway narrowing increases resistance. loss of elastic recoil of the lung decreases driving pressure. Inflammation of the airways due to mucosal edema
and increased mucous production
What happens as a result of persistent inflammation?
Goblet cell hypertrophy .Mucus hypersecretion. Loss of ciliated epithelium. Squamous metaplasia
Destruction of alveolar walls. Peribronchiolar fibrosis
What are causes of airflow limitations?
Bronchoconstriction. Bronchial smooth muscle contraction in response to exposure to a variety of stimuli
What causes airway hyperresponsiveness?
Exaggerated bronchoconstrictor response to stimuli
What causes airway edema?
Edema, mucous hypersecretion, formation of thickened mucous plugs
Cough.Wheezing (end expiratory). Shortness of breath. (symptoms may have a seasonal and/or diurnal variations)
Inflammatory response involves which cells
mast cells, t-lymphocytes, macrophages, eosinophils and epithelial cells.
What is the role of eosinophils in astha?
release granular protein that damages bronchial epithelium and promotes airway hyper-responsiveness.
What is the role of lymphocytes in asthma?
produce Cytokines, Leukotriene B-4 and C-4, prostaglandin and histamine.
What is the role of Mast Cells in asthma?
initiate arousal condition in IgE receptors
What do Leukotrienes (Potent Inflammatory Mediators) do?
Increase vascular permeability/edema.Increase mucus production.Decrease mucociliary transport.
Inflammatory cell recruitment
Asthma Classic triad
Chronic episodic dyspnea
Asthma Associated Symptoms (during attack)
Tachypnea, tachycardia, and systolic hypertension
Audible harsh respirations, prolonged expiration, wheezing
Chest pain or tightness
Diminished breath sounds during acute exacerbations
When can symptoms be worse
Diagnosis of Asthma
Signs and symptoms suggestive of asthma
Confirmation of variable expiratory airflow limitation, preferably by spirometry
Exclusion of alternative diagnoses
When should you use spirometry?
Order before and after bronchodilators. Or can have pt monitor peak flows at home for a month and keep diary of symptoms.
How would you work up asthma in clinic visit?
Can do a quick challenge in the office with a peak flow meter before and after a bronchodilator.
Chest xray only if you need to exclude other causes or if you are suspecting new onset asthma in a middle aged adult
Foreign body ingestion
Congestive heart failure
Panic disorder, hyperventilation syndrome
Vocal Cord Dysfunction
Cough secondary to drugs (ACE inhibitors)
Describe Atopic Extrinsic Asthma
Most common. Onset is usually the first two decades of life. Associated with other allergic manifestations and Family history. Serum IgE and eosinophil count are usually elevated
How is asthma managed?
Routine monitoring. Patient education.Control of triggers and comorbid conditions. Pharmacologic therapy
used to measure how well air moves out of the lungs. Measures how fast air comes out of the lungs with forceful exhalation after inhaling fully.
Benefits of Peak Flow measurments
Learn what triggers their asthma
Decide if the asthma action plan is working
Decide when to add or adjust asthma medications
Know when to seek emergency care
can help providers and their patients monitor their asthma.
Can help the patient when their asthma is getting worse
Peak flow may show changes before the patient feels them.
80 to 100 percent of the patients usual or "normal" peak flow rate signals all clear
A reading in this zone means that your asthma is under reasonably good control. It would be advisable to continue your prescribed program of management.
50 to 80 percent of the patients usual or "normal" peak flow rate signals caution. It is a time for decisions.
Your airways are narrowing and may require extra treatment. Your symptoms can get better or worse depending on what you do, or how and when you use your prescribed medication. You and your provider should have a plan for yellow zone readings.
Less than 50 percent of the usual or "normal" peak flow rate. Severe airway narrowing may be occurring. Take your rescue medications right away. Contact your provider now and follow the plan he/she has given you for red zone readings.
Contributing factors to Asthma
Inhaled allergens (medical rx and avoidance)
Food allergies? Tobacco smoke (first and second hand). Rhinitis/sinusitis.GERD.Occupational exposures. Viral respiratory infections
What does leukotriene 4 (LTD4) do?
profound bronchoconstriction, about 1000 x more potent than histamine
What is the “bronchoprovocation test”?
inhalation of irritating agent such as metacholine used if spirometry was normal, but asthma is still suspected diagnosis