Asthma Flashcards
What is the pathophysiology of asthma?
Airway inflammation mediated by the immune system
Widespread narrowing or airways and increased airway reactivity
What are the 3 main risk factors for asthma?
Genetics
Occupation
Smoking
How does genetics lead to asthma?
Atopy
Inherited tendency to IgE response to allergens
Personal/familial (esp maternal) strongest tendency
What % of adult onset asthma cases are occupation related?
10-15%
What are the strongest risk factors for asthma re smoking?
Maternal and grandmother smoking during pregnancy
What are some environmental allergens that may trigger asthma?
House dust mite
Cat
Grass pollen
What are the symptoms of asthma?
Wheeze SOB Tight chest Cough Sputum
What are some triggers for asthma?
Exercise Cold air Smoking Perfume Pets
When is asthma typically at its worst?
Nocturnal and early morning
How does occupational asthma vary weekly?
Better at weekends and holidays
How does asthma vary annually?
Due to environmental antigens
What are the symptoms of moderate acute asthma?
Able to speak and complete sentences HR <110 Resp rate <25 Peak flow 50-75% SpO2 >92%
What are the symptoms of severe acute asthma?
Unable to speak and complete sentences HR >110 Resp rate >25 Peak flow 33-50% SpO2 >92%
What are the symptoms of life threatening acute asthma?
Grunting HR >130 or bradycardic Hypoventilating Altered concious level Exhaustion Arrythmia Hypotension Cyanosis Silent chest Poor resp effort PEF <33% predicted SpO2 <92% PaO2 <8kPa
What are the primary differences between asthma in children and adults?
In children, more common in boys. In adults, more common in women
Children often have more intermittent symptoms
How is asthma controlled in an acute situation?
Oxygen Salbutamol (nebuliser) Prednisilone 40mg/hydrocortisone 100mg Ipratripium (nebuliser) Magnesium sulphate (IV) if no improvement
What is the 1st step in asthma management?
Short acting B2 agonist
Salbutamol/terbutaline
What is the 2nd step in asthma management?
Inhaled corticosteroids
Beclomethasone
When is a patient upped from the 1st to 2nd step?
When using rescue medicine 3x weekly, symptomatic 3x weekly, or waking 1 night a week due to asthma
What is the 3rd step in asthma management?
Long acting B2 agonist and inhaled corticosteroid
Fostair
What is the 4th step in asthma management?
Inhaled long acting muscarinic antagonist
Leukotrine receptor antagonists
What is the 5th step in asthma management?
Long term oral steroids
40-50mg prednisilone
What are some of the side effects of long acting muscarinic antagonists?
GI upset
Dry mouth
headaches
What are some of the side effects of inhaled corticosteroids?
Can cause oral candidiasis
What is the multiunit theory of asthma?
Requires multiple hits and culminate in asthma Genes Inherently abnormal lungs early onset atrophy Later exposure
How is childhood asthma diagnosed?
All in the history Peak flow done but unhelpful (variable) Wheeze SOB at rest Responds to treatment
