Asthma Flashcards
1
Q
List 4 characteristic clinical features of asthma
A
- cough
- Dyspnoea
- Wheeze
- Chest tightness
2
Q
List the features that characterise a moderate asthma attack
A
- Worsening symptoms
- No features of acute severe asthma
- PEFR >50% of best/predicted
3
Q
List the features that characterise an acute severe asthma attack
A
- Inability to complete sentences in a single breath
- PEFR <50% of best/predicted
- RR ≥ 25
- HR ≥ 110
4
Q
List the features that characterise a life-threatening asthma attack
A
- Poor respiratory effort
- Cyanosis
- Silent chest
- Hypotension
- Arrhythmia
- Exhaustion
- Reduced conscious level
- PEFR < 33% of best/predicted
- SpO2 < 8KPa
- Normal PaCO2 = 4.6 - 6.0 kPa
5
Q
What is the initial treatment for acute asthma?
A
- Sit upright
* Salbutamol 5mg and ipratropium bromide 0.5 mg via oxygen-driven nebuliser
6
Q
Should patients display an inadequate response to initial therapy, what further treatments can be given?
A
- Repeat salbutamol 5mg via oxygen-driven nebuliser if inadequate response and give prednisolone 40mg orally (PO) or hydrocortisone 100mg IV if unable to swallow.
- Consider “back-to-back” salbutamol nebulisers or continuous salbutamol nebuliser 5-10 mg/h if inadequate response.
- Consider magnesium sulphate 1.2-2.0g IV over 20 minutes in life threatening or near-fatal asthma or in acute severe asthma with an inadequate response to initial therapy
- consider aminophylline 5 mg.kg IV loading dose over 20 minutes followed by 0.5 mg/kg/h IV maintenance dose in life-threatening or near-fatal asthma with an inadequate response to initial therapy.
7
Q
What features would concern you on an ABG in acute asthma?
A
- Low pH
- PaCO2 >4.6kPa
- PaO2 < 8kPa
8
Q
What are the indications for requesting a CXR in acute asthma?
A
- suspected pneumothorax or consolidation
- life threatening asthma
- Failure to respond to initial therapy
- Requirement for ventilation
9
Q
What criteria would mandate admission for acute asthma?
A
- Life-threatening asthma
- Near-fatal asthma
- Acute severe asthma persisting despite initial therapy
10
Q
What criteria must be achieved to consider discharge following acute asthma?
A
- PEFR > 75% of best/predicted 1 hour after initial therapy
11
Q
What would you check before discharge?
A
- Give prednisolone 40 mg once daily for 5 days
- Check inhaler technique and ensure sufficient, in-date inhaled bronchodilator
- Arrange follow up with GP in two days
12
Q
What is the definition of asthma and what are the 3 main components?
A
- Chronic inflammatory disease of the airways.
- 3 components:
1. Reversible and variable airflow obstruction
2. Airway hyper-responsiveness to stimuli
3. inflammation of the bronchi
13
Q
What is the Epidemiology of Asthma?
A
- Increasing prevalence - estimates of prevalence range from 3-5.4 million
- Approximately 235 million people worldwide affected
- Approximately 250,000 people die per year form the disease
14
Q
What is the aetiology of asthma?
A
- Atopy and allergy - pets, pollen
- cold air
- Exercise
- Pollution
- Occupational
- e.g. isocyanates (paint sprayers), latex, flour, and grain dust
- Viral infections
- Drugs
- E.g. NSAIDs, Beta Blockers
- Emotion
15
Q
What are the main presentations of asthma?
A
- Cough
- Wheeze
- Breathlessness
- Chest tightness
16
Q
Which features increase the probability of asthma?
A
- Diurnal variation (worse at night and early morning)
- Triggered by or made worse by aetiologies e.g. cold air
- Recurrent and frequent symptoms
- Family history of atopy or asthma
17
Q
What are the differential diagnosis of asthma
A
- Respiratory
- Churg-Strauss: Look for high eosinophils
- Allergic bronchopulmonary aspergillosis: Allergy testing for common moulds
- COPD (exacerbation)
- Chronic cough syndromes
- Rhinitis
- Bronchiectasis
- Sarcoidosis
- Lung cancer - In children
- Croup and epiglottitis
- Obliterative bronchitis
- Cystic fibrosis/Ciliary dyskinesia - GORD
- Heart failure
- Tracheomalacia: Narrow trachea on bronchoscopy, obstructive picture on spirometry
- Vocal cord dysfunction
18
Q
What is used to investigate Asthma?
A
- Peak flow charts
- Lung function tests
- FEV1/FVC < 0.7
- Reversibility/ improvement after trial treatment
- CXR
- In patients presenting atypically or with additional symptoms or signs
- Tests of atopy
- Skin prick testing
- Blood eosinophilia
- Raised specific IgE
19
Q
What further investigations for asthma can be carried out?
A
- Methacoline PC20 - the provocative concentration of methacholine required tor cause a 20% fall in FEV1…
- FEno - Exhaled NO concentration
- Indirect challenges - e.g. exercise challenge
- Sputum eosinophil count
20
Q
What investigations are carried out in acute asthma?
A
- CXR
- Recommended in the presence of suspected pneumothorax, consolidation, life threatening asthma, requirement for ventilation, failure to respond to treatment - Pulse oximetry
- ABG.
21
Q
What are the different stages of acute asthma?
A
- Moderate asthma
- Acute severe asthma
- Life-threatening asthma
- Near-fatal asthma
22
Q
What are the features of moderate asthma?
A
- Increasing symptoms
- PEF > 50-75% best or predicted
- No features of acute severe asthma
23
Q
What are the features of acute severe asthma?
A
Any one of:
- PEF 33-50% best or predicted
- Respiratory rate ≥ 25/min
- Heart rate >110 min
- Inability to complete sentences in one breath
24
Q
What are the features of life threatening asthma?
A
Any one of the following in a patient with severe asthma:
- Clinical signs:
- Altered conscious level
- Exhaustion
- Arrhythmia
- Hypotension
- Cyanosis
- Silent chest
- Poor respiratory effort - Measurements
- PEF < 33% best or predicted
- SpO2 < 92%
- PaO2 < 8 kPa
- “normal” PaCO2 (4.6-6.0 kPa)
25
What is the main feature of near-fatal asthma?
Raised PaCO2 and/or requiring mechanical ventilation with raised inflation pressures.
26
What is the initial management of acute asthma?
1. Oxygen: aim sats 94-98%
2. Inhaled/Nebulised high dose beta 2 agonists - e.g. 2.5-5mg nebulised salbutamol at 15-30min intervals
3. steroid therapy
- 40mg prednisolone po daily for 5 days. if oral route not possible - IV hydrocortisone 400mg daily or IM methylprednisolone 160mg daily
O - SHIT.
27
What is the management for patients who are failing to respond to initial treatment or with acute severe or life threatening asthma?
* Nebulised ipratropium bromide - 0.5mg 4-6 hourly
* Magnesium sulphate - 1.2-2g IV infusion over 20 minutes
* IV aminophylline - 5mg/kg loading dose IV over 20 minutes (unless already on oral therapy), then infusion of 0.5-0.7mg/kg/hr - if on oral maintenance therapy, check level on admission. - monitor levels whilst on infusion (aim 10-20mg/l)
* Early referral to ITU indications include:
- Deteriorating PEF
- Persisting or worsening hypoxia
- Hypercapnia
- Fall in pH in ABG
- Exhaustion
- Reduced GCS
28
How is chronic asthma managed non-pharmacologically?
* Self-management plan
* Allergen avoidance
* Smoking cessation
* Immunisations
* Immunotherapy
29
How is chronic asthma managed pharmacologically?
Using a step wise approach, which you can move up or down..
30
What are the steps involved in the pharmacological management of chronic asthma?
```
Step 1: Reliever therapy
Step 2: Regular preventer therapy
Step 3: Add- on therapy
Step 4: Addition of a 4th drug
Step 5: Oral steroids
```
31
What is step 1 of chronic asthma management?
Step 1: Reliever therapy
- Short acting beta-2 agonist as required: Salbutamol 100-200mcg
32
What is step 2 of chronic asthma management?
Step 2: Regular preventer therapy
- Introduce inhaled steroid if: exacerbations in last 2 years; using salbutamol 3x/wk; symptomatic 3x/week; waking one night/wk
- Usual starting dose 200mcg bd (Budesonide – alternatives include beclomethasone and fluticasone)
33
What is step 3 of chronic asthma management?
Step 3: Add-on therapy
- Trial long acting beta 2 agonist (LABA): Salmeterol 50mcg/12h
- If no response to LABA: stop LABA and increase inhaled steroid dose to 800mcg/day
- If some, but inadequate, response to LABA: increase inhaled steroid dose to 800mcg/day. And if still inadequate response consider alternative add-on therapy:
1. Leukotriene receptor antagonist (first choice add-on therapy in children)
2. Theophyllines
3. Slow release beta 2 agonist tablets
34
What is step 4 of chronic asthma management?
Step 4: Additon of a 4th drug
- If control remains inadequate, consider the following interventions:
- Increasing inhaled steroids to 2000 micrograms/day
- Adding 4th drug e.g. leukotriene receptor antagonist; theophylline; slow release β2 agonist tablets (caution in patients already on long-acting β2 agonists
35
What is step 5 of chronic asthma management?
Step 5: Oral steroids
* Add regular oral prednisolone (at lowest dose for symptom control)
- Monitor for systemic side effects: BP, blood glucose, bone mineral density, cholesterol
* Continue high dose inhaled steroid
* Refer to specialist asthma clinic
36
What can good asthma control be defined as:
1. No daytime symptoms
2. No night-time awakening due to asthma
3. No need for rescue medication
4. No exacerbations
5. No limitations on activity including exercise
6. Normal lung function (in practical terms FEV1 and/or PEF > 80% predicted or best)
7. Minimal side effects from medication
37
What are the complications of asthma?
1. Pneumonia
2. Lobar collapse
3. Pneumothorax
4. Respiratory failure
5. Side effects from treatment - Hypokalaemia, arrhythmias
6. Fatigue
7. Psychosocial problems: depression, difficulties at work
38
What are markers of poorer prognosis in asthma?
1. Poor adherence
2. Previous acute admissions and/or intubation
3. 3+ different classes of asthma medication
4. psychosocial dysfunction
5. Inadequately treated disease
6. Smoking
39
What are the NICE guidelines for the management of asthma?
1. Add short-acting beta 2 agonist inhaler (e.g. salbutamol) as required for infrequent wheezy episodes.
2. Add a regular low dose inhaled corticosteroid.
3. Add an oral leukotriene receptor antagonist (i.e. montelukast).
4. Add LABA inhaler (e.g. salmeterol). Continue the LABA only if the patient has a good response.
5. . Consider changing to a maintenance and reliever therapy (MART) regime.
6. Increase the inhaled corticosteroid to a “moderate dose”.
7. Consider increasing the inhaled corticosteroid dose to “high dose” or oral theophylline or an inhaled LAMA (e.g. tiotropium).
8. Refer to a specialist.
40
What are the BTS/SIGN guidelines for the management of asthma?
1. Add short-acting beta 2 agonist inhaler (e.g. salbutamol) as required for infrequent wheezy episodes.
2. Add a regular low dose corticosteroid inhaler.
3. Add LABA inhaler (e.g. salmeterol). Continue the LABA only if the patient has a good response.
4. Consider a trial of an oral leukotriene receptor antagonist (i.e. montelukast), oral beta 2 agonist (i.e. oral salbutamol), oral theophylline or an inhaled LAMA (i.e. tiotropium).
5. Titrate inhaled corticosteroid up to “high dose”. Combine additional treatments from step 4. Refer to specialist.
6. Add oral steroids at the lowest dose possible to achieve good control.
