Long term CCs part I Flashcards
Define Asthma
Episodes of reversible airway obstruction characterised by wheeze, cough, sputum and SOB
What percentage of the population does asthma affect and in what proportion?
5-8% of the population
Children: boys >girls
Adults: Girls > boys
What are the 3 factors which contribute to bronchial airway narrowing?
- Bronchial muscle contraction triggered by stimuli
- Mucosal swelling/ inflammation caused by masts cell and basophil degranulation= release of inflammatory mediators
- Increased mucus production
Risk factors for asthma?
Cold air Exercise Emotion Allergens e.g. dust mite/ pollen fur Infection/ URTI esp in children Smoking Pollution FamHx of atopy Social deprivation
Key features of an asthma history?
Any questionnaires that can be used?
Ask about other atopic disease e.g. eczema, hayfever, allergy or FamHx
Ask about house setting, pets, carpet, feather pillows or duvet
Ask about occupation: if symptoms remit at the weekend work may provide trigger
Quantify exercise tolerance and effect on ADLs
Quantify nights of disturbed sleep
Asthma control questionnaire can be used (ACQ)
Clinical signs of Asthma
Clinical signs of life threatening asthma?
Tachypnoea Hyperinflated chest Hyper-resonant percussion note Decreased air entry Audible wheeze
Confusion: due to cerebral hypoperfusion
Exhaustion
Silent chest
Cyanosis= (PaO2 <8kPa but PaCO2 4.6-6.0, SPO2<92%)
Bradycardia: heart is fatigued
Define FEV1 and FVC and explain their ratios
FEV1: The volume of air that an individual can forcefully exhale in 1 second: time dependent: reflects airway caliber
FVC: Forced vital capacity: The amount of air that can be forcibly exhaled from the lungs after taking the deepest breath possible- volume dependent: reflects lung volume not caliber
FEV1/FVC Ratio: This is used to distinguish between obstructive and restrictive conditions
- Ratio <0.7= obstructive: due to narrowing of airways
- Ratio >0.7= restrictive: due to reduced total lung capacity
What’s the NICE diagnostic algorithm for children <5
To treat symptoms based on observation- review the child regularly
Use skin prick test to aeroallergens or specific IgE tests to identify triggers after formal diagnosis made
What’s the NICE diagnostic algorithm for children ages 5-17?
What are the positive thresholds?
- Perform Spirometry in children and young people with asthma symptoms
- If they can’t do 1. Treat based on observation/ clinical judgement and try doing the tests again every 6-12 months
- If still unsure after spirometry and Bronchodilator reversibility, consider FENO
- If still unsure after 1-3, monitor peak flow variability for 2-4 weeks
Positive thresholds
- Obstructive spirometry: FEV1/FVC<0.7/ 70% or below the lower limit of their normal
- FENO 35ppb or more
- BDR: Improvement in FEV1 of 12% or more
- Peak flow variability: Over 20%
What’s the NICE algorithm for adults?
What are the positive thresholds?
Confirm occupational asthma first- then refer to specialist if positive. Otherwise…
- Measure FENO first then Spirometry with symptomatic adults
- If unsure after FENO, spirometry and BDR- monitor peak flow variability for 2-4 weeks
- If still unsure after peak flow variability, refer for a histamine or methacholine direct bronchial challenge test
- If Meta or bronc.chall. test is unavailable- suspect asthma and review diagnosis after treatment OR refer to a center with access to histamine or methacholine challenge
Thresholds
- Obstructive spirometry: FEV1/FVC<0.7/ 70% or below the lower limit of their normal
- FENO 40ppb or more
- BDR: Improvement in FEV1 of 12% or more and increase in volume of 200m or more
- Peak flow variability: Over 20%
- Direct bronchial challenge test with histamine or methacholine: PC20 of 9mg/ml or less
Explain to your patient how to perform a peak flow test
o Standing or sitting up – preferably standing
o Ensure pointer at zero and fingers not obstructing
o Full breath in, rapid forced expiratory puff through meter, tight seal around mouthpiece
o Best of 3 readings recorded
What mnemonics would you use to explain a diagnosis of asthma (or any disease tbh)
BUCES, Brief history, understanding, concerns, explanations, summarise
NWCPM, Normal anatomy/ physiology, what the disease is, cause, problems/ complication and management
see osce notes for more info
What are the 2 main self management methods in asthma?
Patient education: Should include discussion of issues such as trigger avoidance and occupational exposure to support people and their families living with asthma. Encourage a smoke free environment
PAAP: : Asthma.org.uk contains good examples: There’ll be specific advice about recognising loss of asthma control, assessed by symptoms or peak flows or both
Differentiate between primary, secondary and tertiary management
Primary: Stop yourself from getting it. Secondary, detect disease early and prevent it from getting worse
Tertiary- trying to improve your quality of life and reduce symptoms of a disease you already have
What are the methods of non-pharmacological management
Avoidance of aeroallergens
Reduce pet contact
Food allergen avoidance- esp eggs. This should not be offered as primary prevention advice, just be aware of it
Breastfeeding: has potential protective effect in relation to early asthma
Weight reduction is recommended in obese patients
Warn patients and families about the dangers of smoking and second-hand tobacco smoking exposure
What is a phased approach in asthma management
Aims to abolish symptoms asap and optimise peak flow by starting treatment at the level most likely to achieve this.
Aim for early control and step up or down as required
Before starting something new, practitioners should check adherence with existing therapies, check inhaler technique and eliminate trigger factors