Respiratory - Asthma Flashcards
What is the natural history of asthma?
more common in children with a personal or family history of atopy polyphonic wheeze is noted from airways
What are the key features of history of asthma?
symptoms worse at night and early in the morning
symptoms that have non-viral triggers
interval symptoms - between acute exacerbations
personal or family history of an atopic disease
positive response to asthma therapy
What are the key features of asthma on examination?
polyphonic wheeze with prolonged expiratory phase
may be hyperinflation of the chest in long-standing asthma
evidence of eczema should be sought as should examination of nasal mucosa for allergic rhinitis
presence of wet cough or sputum production suggests cystic fibrosis and bronchiectasis
atypical features: sputum, finger clubbing, growth failure - seek another diagnosis
What common clinical conditions that mimic asthma?
gastrooesophageal reflux cystic fibrosis viral induced wheezing bronchiolitis croup
How is asthma investigated?
usually diagnosed from history and examination
skin prick test can be used for common allergen
peak expiratory flow
spirometry
Describe moderate acute asthma?
- able to talk
- oxygen saturation >92%
- peak flow - respiratory rate (<40 breaths/min for 2-5 years<30 breaths/min for 5-12 years<25 breaths/min for 12-18 years)
- heart rate (<140 b/m for 2-5 year <125 b/m for 5-12 year<110 b/m for 12-18 year)
What is severe acute asthma?
- to breathless to talk oxygen sats <92% for <12 year olds- Peak flow 33-50% (best)
- Respiratory rate (>40 breaths/min for 2-5 years>30 breaths/min for 5-12 years>25 breaths/min for 12-18 years)
- Heart rate (>140 b/m for 2-5 year >125 b/m for 5-12 year>110 b/m for 12-18 year)
What are the signs of life-threatening asthma?
silent chest cyanosis poor respiratory effort exhaustion arrythmia hypotension altered consciousness agitation, confusion peak flow <33% oxygen saturation <92%
How do you manage moderate asthma?
- Reassure
- Short acting B2 agonist via spacer (face mask for under 3)2-4 puffs increasing by 2 puffs every 2 min
- oral prednisolone 1-2mg/kg, max 40mg
- monitor for 15-30 min
How do you manage severe asthma?
- High flow oxygen
- Short acting B2 agonist via spacer, 10 puffs or nebulised (2.5 mg <8 years, 5mg >8years) assess response and repeat
- Oral prednisolone or IV hydrocortisone Consider:- inhaled ipratropium
- IV B2 agonist
How should life threatening asthma be managed?
- Short acting B2 agonist nebulized
- asses response continuously and repeat as required
- oral prednisolone or IV hydrocortisone
- nebulized iprtropium Consider:
- IV B2 agonist or aminophylline or magnesium
Discuss with PICU
What should be done after an acute asthma attack?
Continue bronchodilators 1-4prn
Discharge when stable on 4 hr treatment
Continue oral prednisolone for 3-7 days
Review meds/technique at discharge, asthma plan, arrange follow up
What should happen if not responding to asthma treatment?
Transfer HDU/PICU Ensure senior medical review Consider IV therapies Consider CXR (pneumothorax or infection?) and blood gases Consider need for mechanical ventilation
What drugs are given as bronchodilators?
Inhaled B2 agonists are the most commonly used an most effective bronchodilators
What are SABAs?
Salbutamol or terbutaline Have a rapid onset of action (maximum effect in 10-15 mins) are are effective for 2-4 hours
What are LABAs?
Salmeterol or formoterol Effective for 12 hours
Not used in acute asthma
Should be used without an inhaled corticosteroid LABAs are used in exercise induced asthma
What is Ipratropium bromide?
An anticholinergic bronchodilator
Sometimes used in young infants when other bronchodilators are found to be ineffective or in treatment of severe asthma
What type of drugs are used in preventer therapy?
Inhaled steroids Long acting B2 agonists (LABA) Methylxanthines Leukotriene receptor antagonists (LTRAs) Oral steroids Anti-IgE monoclonal antibodies
What is the most effective prophylactic therapy for asthma?
Inhaled corticosteroids
What are examples of inhaled corticosteroids?
Budenoside
Beclomethasone
Fluticasone
Mometasone
What are inhaled corticosteroids used for?
only effective if taken regularly
decrease airway inflammation
decrease symptoms, exacerbations,
bronchial hyperactivity often used in conjunction with a LABA/leukotriene receptor antagonists
given at lowest dose possible to reduce side effects
What other add on therapy can be given in asthma?
Children under 5: leukotriene receptor antagonist - e.g. montelukast
Children over 5: LABA
What other therapies can be added in more severe asthma?
Oral Prednisolone (usually given on alternative days) Anti IgE therapy (used in severe atopic asthma) Antihistamines and nasal steroids (used in allergic rhinitis)
What is the FIRST STEP of the 5 steps of SIGN/NTS guidelines for management of asthma?
Preventer therapy:
very low dose ICS (or LTRA <5 years) AND short acting bronchodilator PRN
What is the SECOND STEP of the 5 steps of SIGN/NTS guidelines for management of asthma?
Initial add on therapy: very low dose ICS PLUS >5 years add LABA <5 years add LTRA AND short acting bronchodilator PRN
What is the THIRD STEP of the 5 steps of SIGN/NTS guidelines for management of asthma?
Additional add on therapy:
If no response to LABA: stop and increase ICS to low dose
If benefit from LABA but control still inadequate: continue LABA and increase ICS to low dose or consider trial of LTRA
What is the FOURTH STEP of the 5 steps of SIGN/NTS guidelines for management of asthma?
High dose therapies: Consider trials of:- increasing ICS to medium dose- addition of fourth drug (SR theophylline) refer patient to specialist care
What is the FIFTH STEP of the 5 steps of SIGN/NTS guidelines for management of asthma?
Continuous or frequent use of oral steroids:
- use daily steroid tablet in lowest possible does for control
- maintain medium dose ICS
- consider other treatments to minimise use of steroid tablets
What are good questions to assess childhood asthma?
how frequent are the symptoms? what are the triggers the symptoms? Sport? General activities affected? How often is sleep disturbed? How severe are symptoms between exacerbations? How much school has been missed?
How should you counsel the parent and child about how to look after asthma?
What drugs should be used and when What each drug does How to use the drug How often and how much can be used What to do if asthma worsens (written action plan should be compiled)
