Asthma Flashcards
What did the British Thoracic Society/SIGN 2019 state about how is asthma diagnosed?
No consistent gold standard diagnostic criteria
Central to diagnosis is presence of symptoms
–More than one of wheeze, breathlessness, chest tightness, cough
–Variable airflow obstruction
What is the definition of asthma?
Heterogeneous disease characterised by chronic airways inflammation
What is the WHO definition of asthma?
Is a disease characterized by recurrent attacks of breathlessness and wheezing, which vary in severity and frequency from person to person. In an individual, they may occur from hour to hour and day to day.
On average, _____ people die from an asthma attack in the UK every day
Does the UK or EU have higher asthma death rates?
3
UK
When does asthma most commonly first present?
Asthma most commonly presents in childhood or in middle age
At what age will the majority of children be asthma-free?
Age 21
Which patients with asthma are more likely to have persistant asthma?
Adult-onset asthma is more likely to be persistent
70% of children with more persistent asthma will continue to have symptoms in adult life
What causes the airflow obstruction?
- Bronchoconstriction - contraction of the smooth muscle in the bronchial wall
- Bronchial secretions and plugs of mucus - due to inflammation of the bronchial wall
- Oedema of the bronchial wall - due to inflammation the lining mucosa of the bronchial wall
What is atopy?
- Asthma in young people usually linked to atopy
- Tendency to form IgE antibodies to allergens (such as pollen, house dust mites or animals).
- Often associated hay fever or eczema in the personal or family history
Complete the diagram on asthma pathophysiology
What are the symptoms of asthma?
- Cough
- Wheeze
- Breathlessness
- Chest tightness
When do asthma symptoms occur?
Occurs in episodes with periods of no (or minimal symptoms)
Diurnal variability-so worse at night or early morning
Which medications are triggers for asthma?
–Aspirin
–Ibuprofen
–Beta blockers
List the triggering factors for asthma
How is a diagnosis of asthma made?
- History is crucial-need more than one symptom
- Symptom free periods
- Past medical history (previous wheezing illness, hay fever, eczema), family history (of any atopic disease), and social history (occupation, pets) can provide clues
- Physical examination may be normal except during an attack
What are the investigations for asthma?
•Tests done by GP-
Peak flow monitoring-twice day for 2 weeks
Spirometry may show airflow obstruction, but may be normal between attacks
•Tests done by GP/Hospital
Chest X-ray often normal, but may show hyperinflation
Increased eosinophil count in the blood
Fraction exhaled nitric oxide (FeNO)
•Tests done by hospital
Skin prick or blood tests may confirm allergies
What tests of lung function are done for asthma?
•Is there airflow obstruction?
–FEV1/FVC ratio <70
•Does it vary over time?
–peak expiratory flow rate (PEFR) monitoring-20% diurnal variation worse at night/early morning
•Is it reversible?
–with bronchodilators (so after treatment with salbutamol) 15% and 200mls improvement in FEV1 from baseline
What does this peak flow show?
Nocturnal variation
What is FeNO-Fraction of exhaled nitric oxide?
- Measure of airways eosinophilic inflammation
- Performed on patients not on any treatment, a positive test (> 40ppb) supports diagnosis of asthma
- Can be done in GP and hospital clinics
- Can be used to monitor treatment/look at compliance
What are the non-pharamcological management of asthma?
–Smoking cessation
–Weight reduction
–Pollution-may provoke acute asthma or aggravate existing asthma but effects from allergens, smoking and infection more significant
What preventers can be used in asthma?
–Inhaled corticosteroids (ICS)
- Key part of first line treatment in patients with asthma
- Beclometasone, fluticasone, budesonide, ciclesonide
–Inhaled Long acting beta 2 agonists (LABA)
- Formoterol, salmeterol
- In combination with ICS as add on treatment if still symptomatic
- Never a single agent treatment alone: associated with increased deaths
What are the long term oral treatments for asthma?
–Oral leukotriene antagonist-montelukast
–Oral theophyllines
–In patients with chronically poorly controlled asthma: low dose longterm oral steroids (prednisolone). Hospital directed treatment
What are the relievers for asthma?
Short/immediate relief of symptoms (relievers)
•Short acting beta agonists (SABA)
–Salbutamol
–Terbutaline
–As inhaler (salbutamol 100mcg) or nebuliser (high dose salbutamol 2.5mg, driven by oxygen)
What is maintenance and reliever therapy (MART) for asthma?
- LABA formoterol has short onset of action
- Equivalent of salbutamol (SABA)
- So certain specific ICS/LABA combinations can be used as relievers as well as preventers
- So patients can take additional doses (4/day) for short period (2-3 days) to rapidly treat any worsening asthma symptoms
- Aim to address and treat the inflammatory aspect of disease by having both ICS and LABA
Complete the diagram on the guidelines for treating asthma
What are the 2 different inhaler devices?
Dry power inhalers
Pressurised metered dose inhalers
How do dry power inhalers work?
•Activated by inspiration by the patient
•Powdered drug is dispersed into particles
by the inspiration
How do pressurised metered dose inhalers work?
Drug dissolved in a propellant hydrofluorocarbons (HFCs) under pressure Valve system releases a metered dose
Which inhaler device is associated with better technique?
DPIs
Which inhaler device is this?
What should GP/practice nurse/ hospital doctor consider before prescribing an inhaler?
- Where are they in treatment (so stepping up going from ICS to ICS/LABA
- What device can they use
- Dexterity
- Inspiratory flow
- Side effects-oral candidiasis/thrush (ICS), tremor + tachycardia (SABA/LABA)
- What device do they want to use (HFCs) - carbon footprint
- Counter so know how many doses left
Cost
What are the 3 key questions to ask asthma patients?
- Have you had difficulty sleeping because of your asthma symptoms (including cough)?
- Have you had your usual asthma symptoms during the day (cough, wheeze, chest tightness or breathlessness)?
- Has your asthma interfered with your usual activities (eg housework, work, school)?
Name 2 very specialised treatments for small numbers of patients with difficult asthma?
•Monoclonal antibody
–anti-IgE injections (omalizumab)
–anti IL-5 treatment (mepolizumab)
•Bronchial thermoplasty
What factors may effect patient adherence or compliance with treatment?
•Unintentional
Misunderstanding
Poor inhaler technique
Language
Forgetfulness
Stress
Intentional
Concern about side-effects
Denial
Cost
What does a personal asthma action plan (PAAP) do?
–Improves asthma control
–Reduces emergency contacts with GP
–Reduces hospital admissions
When is asthma a medical emergency?
Acute Severe asthma
What are the features of acute severe asthma?
–Peak expiratory flow rate (PEFR) 33-50% of best (use % predicted if recent best unknown)
–Can’t complete sentences in one breath
–Respirations ≥25 breaths/min
–Pulse ≥110 beats/min
When does acute severe asthma become life threatening?
–PEFR <33% of best or predicted
–SpO2 <92% (regardless of air or oxygen)
–Silent chest, cyanosis, or feeble respiratory effort
–Arrhythmia or hypotension
–Exhaustion, altered consciousness
How is acute severe asthma managed?
- Oxygen- how? What target saturations?
- Corticosteroids - prednisolone 40-60 mgs orally (intravenous hydrocortisone if unable to take orally)
- Nebulised bronchodilators – salbutamol + ipratropium bromide
- If poor response, intravenous MgSO4, or intravenous aminophylline
- Exceptionally, intubation and ventilation is required
When are patients with acute severe asthma discharged from hospital?
- Been on discharge medication for 24 hours
- Inhaler technique checked and recorded
- Increase in PEFR >75% of best or predicted and PEFR diurnal variability<25%
What is an acute severe asthma patient discharged with?
- Treatment with oral and inhaled steroids in addition to bronchodilators
- Own PEFR meter and written PAAP
- GP/Nurse follow up arranged within 2 working days
- Follow up appointment in respiratory clinic within 4 weeks
