What is an acute asthma exacerbation?
- Worsening of asthma symptoms
What are the symptoms of an acute asthma exacerbation?
- Cough
- Wheezing
- Dyspnoea
- Chest tightness
- Sleep disturbance
- Accessory muscle use
- Tachypnoea
- Tachycardia
- Inability to speak
- Cyanosis
What assessments would you do in a primary care setting for someone showing an acute asthma exacerbation?
- HR
- Respiratory rate
- Oxygen saturation
What investigations would you order in an acute asthma exacerbation?
- PEFR
- Oxygen saturation
- ABG
- CXR
What would a PEFR result show in an acute asthma attack?
Measure as a percentage of their best predicted
- 50-33% = acute asthma attack
- <33% = life-threatening
What would an oxygen saturation result possibly show in an acute asthma attack?
<92% = life-threatening
What should you aim for regarding oxygen saturation?
94-98%
When would you order an ABG test?
When oxygen saturation is <92%
What would an ABG result possibly show in an acute asthma attack?
- Initially respiratory alkalosis
Tachypnoea causes a decrease in CO2 - Normal CO2 or hypoxia
Concerning as indicates patient is tiring and life-threatening asthma - Respiratory acidosis
Increase in CO2
What would an CXR result possibly show in an acute asthma attack?
Hyperinflation
What is a CXR useful for?
Identification of co-existing conditions and to rule out others
- Congestive HF
- Foreign body aspiration
- Pneumothorax
What does moderate acute asthma look like?
- Increasing symptoms
- PEF >50-75% best or predicted
- No features of acute severe asthma
What does acute severe asthma look like?
- PEF 33-50% best or predicted
- Respiratory rate ≥ 25/min
- HR ≥ 110/min
- Inability to complete sentences in one breath
What does life-threatening asthma look like?
- PEF <33% best or predicted
- SpO2 <92%
- ABG:
PaO2 <8kPa
‘Normal’ PaCO2 (4.6-6.0kPa) - Altered conscious level
- Exhaustion
- Arrhythmia
- Hypotension
- Cyanosis
- Silent chest
- Poor respiratory effort
What does near-fatal asthma look like?
- Raised PaCO2 and/or requiring mechanical ventilation with raised inflation pressures
What are the aims of treatment of an acute severe asthma attack?
- Relieve airflow obstruction
- Prevent further relapses
What could a patient do in a non-medical setting to treat an acute severe asthma attack?
4 puffs of salbutamol initially, then 2 puffs every 2 minutes of salbutamol through spacer
What would you give a patient in a primary care setting to treat an acute severe asthma attack?
- Inhaled SABA and O2 with nebuliser or spacer
- Steroids
IV Hydrocortisone 100mg or Oral (PO) prednisolone 40-50mg - Insert IV cannula
For useful drugs if needed - Give inhaled ipratropium bromide combined with the
SABA if asthma life-threatening, severe or poor response to initial SABA - Sit them upright
- Document all treatments
Times, routes and doses
What is the criteria for admission to hospital with asthma?
- Life-threatening or near-fatal asthma attack
- Severe asthma attack persisting after treatment
What additional medications might you give a patient in hospital to treat an acute severe asthma attack?
- IV magnesium sulphate
If not had a good initial response to therapy - IV aminophylline
Consultation with senior medical staff
What is the criteria for non-invasive ventilation and admission to ICU?
Hypercapnic respiratory failure
What must you continue to measure during an acute severe asthma attack?
- PEFR
15-30 mins after starting treatment
- O2 saturation
- Repeat ABG
- HR
- Respiratory rateWhat must you measure during an acute severe asthma attack if there are no signs of improvement?
- Serum potassium
Salbutamol can cause potassium absorption into cells - Blood glucose
- Serum theophylline
Only if aminophylline is continued >24hrs
After an acute severe asthma attack, what medication should be continued until recovery?
Prednisolone (40-50mg) daily for minimum 5 days
