Clinical features of asthma in Adulthood Flashcards
What is asthma?
Increased responsiveness of the airways, airflow or airway obstruction, and symptom variability.
Derived from the Greek term (aazein), meaning “to pant heavily” or “gasp for breath”
Complex disease or syndrome for which there is no universally accepted definition
A disease characterised by an increased responsiveness of the trachea and bronchi to various stimuli and manifested by a widespread narrowing of airways that changes in severity either spontaneously or as a result of therapy
When are asthma symptoms most marked?
Often at the beginning or end of the day
What are the symptoms of asthma?
Wheezing Shortness of Breath Difficulty expiration Chest tightness Coughing
True or False:
Every day 3 people die from an asthma attack, 2/3 of deaths being preventable
Every 10 seconds someone is having a potentially life threatening asthma attack in the UK
True
What is the annual NHS cost of asthma?
£889million
What are the 3 proven risk factors for asthma?
Hereditary
Smoking
Occupation
What is Atopy?
Body’s predisposition to develop an IgE antibody (immunoglobulin E) in response to exposure to environmental allergens - inheritable trait.
Associated with allergic rhinitis, asthma, hay fever, and eczema
Risk of asthma increased if first degree family member has asthma or another atopic disease.
Is a paternal or maternal atopy more influencial?
Maternal atopy most influential (3x father).
What % of adult onset asthma can com from Occupation?
What type of work and how?
Underestimated (10-15% of adult onset asthma)
Isocyanates twin pack paints Colophony welding solder flux Laboratory animals rodent urinary proteins Grains wheat proteins, grain mites Enzymes subtilisin, amylase Drugs antibiotics, salbutamol Crustaceans prawns, crabs
What are the possible risk factors for asthma (not for exams) but could explain increase in prevelance?
Obesity
Increased body mass index associated with asthma
Obesity pro- inflammatory
Diet Associations with: Vitamin E,C and D Selenium Polyunsaturated fatty acids Oily fish, Mediterranean diet, margarine
The “hygiene hypothesis”
Reduced exposure to microbes/ microbial products
Children born on farms less likely to develop asthma
Microbial diversity appears to be important in reducing the risk of asthma
What tests are done for airway obstruction?
Spirometry and bronchodilator reversibility
What other options are there for investigations?
Tetsing for variability:
reversibility
PEF charting
Challenge tests
Testing fro eosinophillic inflammartion or atopy:
FeNO
Blood eosinophils
Skin prick test, IgE
What do you look for in a clinical examination of someone with asthma?
- recurrent episodes of symptoms
- symptom variability
- absence of symptoms of alternative diagnosis
- recorded history of wheeze
- personal history of atopy
- historical record of variable PEF/FEV1
Symptoms of asthma
Wheeze Shortness of breath (dyspnoea), severity Chest tightness Cough, paroxysmal, usually dry Sputum (occasional)
Give 3 examples of variation which might be shown
Daily variation (nocturnal/ early morning) Weekly variation (occupation, better at weekends & holidays) Annual variation (environmental allergens)
What could be possible triggers for asthma?
Different for each individual.
Exercise Cold air Cigarette smoke Perfumes/ strong scents URTI’s Pets Tree or grass pollen Food Drugs (aspirin/ NSAIDS)
What would you ask about in past medical history?
Childhood asthma, bronchitis, wheeze in infancy
Eczma
Hayfever
What would you ask about in terms of drugs?
Current inhalers (check technique!), other asthma therapies, compliance
Beta-blockers, aspirin, NSAIDS
Effects of previous drugs/inhalers
What would you try to specifically ask about for family history?
Asthma and other atopic disease
hat would you try to specifically ask about for in social history?
Tobacco, recreational drugs, vaping
Pets
Occupation (past and present)
Psychological aspects
What may you find on clinical examination?
Usually unhelpful but may find:
Breathless on exertion
Hyperinflated chest
Wheeze
What other diseases can cause wheeze, cough and dyspnoea?
Generalised airflow obstruction:
COPD (irreversible AFO)
Bronchiectasis
Cystic Fibrosis
Localised airway obstruction (inspiratory stridor= large airways):
Tumour
Foreign body
Cardiac
Can FEV1/FVC ratio be normal in asthma?
Yes, it can be.
What do you do on result of an obstructed spirometry assessment and why?
What counts as “obstructed”?
Obstructed = FEV1/FVC<70% , FEV1<80% predicted.
You do further examinations: full pulmonary function testing - to remove COPD/emphysema.
What objective points do you look at when evaluating acute asthma ?
think O SHIT Oxygen satration/arterial blood gas Speak ability Heart rate In - respIration rate Test -PEF
Defferentiate Moderate and severe asthma: Oxygen sats Speak Ability Heart Rate respIratory rate Test - PEF SaO2 PaO2
Moderate: vs (Severe (any one of))
Essentially increasing symptoms,
no features of acute severe
Able to speak, complete sentences (inability to complete sentances in one breath)
HR < 110 (110+)
RR < 25 (25+)
PEF 50 - 75% predicted or best (33-50% predicted or best)
SaO2 ≥ 92% - no need for ABG
PaO2 ≥ 8kPa
What are the signs of a life threatening asthma attack?
GAS 33 CCE
Grunting
Arrythmia/hypotention/bradycardia
Silent chest
PEF=33% predicted or best
Confusion/exhaustion/impaired consciousness
Cyanosis
Effort = poor for respiratory
What would the stats be in a life threatening asthma attack?
SaO2 less than 92% (Needs blood gas!) PaO2 = less than 8kPa PaCO2 cormal (4.6-6.0kPa)
Mternal smoking has what affect on the new born?
reduction in FEV1
What are the particular jobs which are high risk of developing asthma?
Bakers, Painters and shellfishworkers
If asthmatics sputum is yellow or green , then does that mean they have a bacterial or viral infection?
No, not necessarily! Could just be the colour of the inflammatoty cells
Can stress make asthma worse
Yes, likewise asthma can make stress worse
If there is finger clubbing, cervical lymphadenopathy, stridor, assymetric expansion, dull percussion note, crepitations, is it probably asthma?
No
Is the wheeze always there in adult asthma?
No
What would stridor (inspiratory wheeze) point towards?
obstruction of large airway, eg tumour/foreign body obstruction of airways.
What do we look at in spirometry?
FEV1 or FEV1/FVC
What would indicate airflow obstruction in a spirometry reading?
less that 70% (FEV1/FVC)
Will asthmatics have normal spirometry?
It may be normal if they don’t have any symptoms at the time or it may be reduced
What do you consider if a suspect asthmatic has an obstructed spirometry result?
Full pulmonary function test and/or reversibility testing
What does a Full Pulmonary function test do?
gas transfer test, gas ytransfer of CO to haemoglobin. In asthma, gas transfer is preserved or even can be increased, whereas COPD is reduced (alveolar reduction and destruction caused by smoking)
What is a reversibility test?
FEV1 before and 15 mins after either inhaled or nebulised dose of Salbutamol (bronchodilator), and check to see if there is an improvement (which would be consistant with asthma)
What level counts as “reversibility”?
Change in FEV1 greater than 200ml and 12% of baseline
What is an alternative method for testing for reversibility?
A course of corticosteroids (anti-inflammatory) eg Prednisolone) for 14 days and keep a peak flow chart and meter. Also compare baseline and x2 week spirometry.
Significant and consistant improvement in peak flow over 2 weeks would suggest asthma (as shows responsiveness and reversibility)
What is the course of action if patient presents with asthma but has a normal spirometry result
Asked to record peak flow over 2 weeks (at least twice daily.
Look for variability of greater that 20% over the recordings/trends/patterns
In specialist investigations for asthma, what chemicals can be used and what are you looking for?
Chemicals used:
Methacholine
Histamine
Mannitol
Asthmatic patients FEV1 will drop off
Why may these aditional investigations be useful: Chest X-ray Skin Pick Testing Total and specfic IgE Full Blood Count
Chest X-ray: Hyperinflated, hyperlucent (no effusion, collapse, opacities, interstitial changes)
Basically trying to rule out if there is any lung consolidations that would fit with pneumonia, pleural effusions, lung cancers, interstitial lung disease
Skin prick testing (atopic status)
Total and specific IgE (atopic status)
Full blood count
Eosinophilia (atopy)
