Asthma Flashcards
What 3 things can cause asthma?
- Chronic airway inflammation
- Airway hyper-responsiveness
- Increased mucus production
What are some examples of environmental & immunological factors that can cause asthma?
Environment: allergy, IgE mediated inflammation from mast cells
Immunology: exposure to allergens, pollution.
What are some examples of asthma presentations?
- Hyperinflation of lungs
- Could be asymptomatic
- Silent chest (life threatening)
What are the types of tests you can do to diagnose asthma?
- Bloods: increased eosinophil count
- CXR: chest x-ray for hyperinflation
- Peak flow diary
- FeNO test: measuring NO breath levels, a sign of inflammation
- Spirometry
What does spirometry measure and what is the expected result of an asthmatic?
It measures the vol. of air inhaled & exhaled.
FEV1/FVC <70% = asthmatic
This ratio can be measured before & after a bronchodilator is given to see if it helps.
What is the skin prick test & what is measured from it?
Allergen is injected into the skin.
Mast cell degranulation present = histamine release = wheal & flare reaction on skin.
If wheal & flare is >3mm = significant reaction
What are the steps taken if someones asthma is getting progressively worse, from a pharmacological point of view?
SABA –> low dose ICS –> +LABA –> increase ICS dose OR + LTRA (montelukast) –> REFER
SABA should be used throughout the whole treatment
What does an asthma action plan contain?
- What to do in poor control/emergency
- Allows self adjustment in deteriorating events
- Personalise a plan to take medication
What can occur during an asthma review?
- Review peak flow diary
- Check spirometry
- Review inhaler technique
- Increase therapy if control is poor
- Aim to decrease ICS dose if asthma is stable to avoid side effects
What are the 3 severities of asthma?
- Moderate
- Peak expiratory flow (PEF) 0.5-0.7 - Severe
- Tachycardia
- Increased HR/RR
- PEF 0.3-0.5 - Life threatening
- Cyanosis
- pO2 <92%
- PEF <0.3
- Silent chest
What are possible managements of asthma, excluding bronchodilators?
- O2 face masks
- Steroids - prednisolone 40mg, or IV hydrocortisone 200mg
- Mg sulphate
- IV aminophylline
When should you refer an asthmatic patient?
- If their CO2 levels are increasing
- If their PEF is decreasing even after treatment
- Increased hypoxia & pH