Asthma, Acute
Standard Treatment Guidelines and Essential Medicines List for South Africa, Hospital Level, Adults 2019 Edition
J45.0-1/J45.8-9
DESCRIPTION
- This is an emergency recognised by various combinations of:
- wheeze
- tightness of the chest
- chest indrawing
- breathlessness
- respiratory distress
- cough
- In adults, bronchospasm is usually associated with asthma (where the bronchospasm is usually completely reversible) or chronic obstructive pulmonary disease (COPD; where the bronchospasm is partially reversible).
|
The clinical picture of pulmonary oedema due to left ventricular heart failure may be similar to that of asthma. If patients >50 years of age present with asthma for the first time, consider pulmonary oedema due to left ventricular heart failure. All PHC facilities must have peak expiratory flow rate (PEFR) meters as asthma cannot be correctly managed without measuring PEFR. |
Recognition and assessment of severity of asthma attacks in adults
| Mild-Moderate | Severe | Life threatening | |
| Oxygen saturation | >90% | <90% | <90% |
| Talks in | phrases | words | Unable to speak |
| Alertness | normal | Usually agitated | agitated, drowsy or confused |
| Respiratory rate | 20–30 breaths/minute | often >30 breaths/minute | often >30 breaths/minute OR feeble effort |
| Wheeze | present | present | absent |
| Heart rate | 100–120 beats/minute | >120 beats/minute | bradycardia |
| PEFR | >60% of predicted | <60% of predicted | <33% of expected or unable to blow |
Note:
PEFR is expressed as a percentage of the predicted normal value for the individual, or of the patient's personal best value obtained previously when on optimal treatment. See PEF charts in Appendix V: Asthma monitoring).
GENERAL MEASURES
- Patients with moderate-severe or life threatening asthma should ideally be closely monitored in a High Care- or Intensive Care Unit.
MEDICINE TREATMENT
- See Appendix VI: Devices for Respiratory Conditions for guidance on inhaler, spacer and nebuliser device techniques.
Mild to moderate attacks
- Salbutamol 100 mcg metered-dose inhaler (MDI),
- Salbutamol inhaler 400–1000 mcg (4-10 puffs) using a spacer if required and available.
LoE:IVbi - Shake the inhaler between each puff.
- If no relief, repeat every 20–30 minutes in the first hour.
- Thereafter, repeat every 2–4 hours if needed.
- Salbutamol inhaler 400–1000 mcg (4-10 puffs) using a spacer if required and available.
Note:
Administering salbutamol via a spacer is as effective as, and cheaper than, using a nebuliser.
OR
- Salbutamol 0.5% (5 mg/mL), solution,
- 1 mL (5 mg) salbutamol 0.5% solution made up to 4 mL with sodium chloride 0.9%, preferably delivered at a flow rate of 8 L/min with oxygen.
- If no relief, repeat every 20–30 minutes in the first hour.
- Thereafter, repeat every 2–4 hours if needed.
LoE:IVbii
PLUS
- Corticosteroids (intermediate-acting) e.g.:
- Prednisone, oral, 40 mg immediately if patient known to have asthma/COPD.
- Follow with prednisone, oral, 40 mg daily for 7 days.
LoE:IVbiii
Severe attacks
- Oxygen to keep oxygen saturation 93-95%.
AND
- Salbutamol 0.5% (5 mg/mL) nebuliser solution,
- 1 mL (5 mg) salbutamol 0.5% solution, made up to 4 mL with sodium chloride 0.9%, preferably delivered at a flow rate of 8 L/min with oxygen.
- If no relief, repeat every 20–30 minutes until PEF > 60% of predicted.
- Once PEF > 60% of predicted, repeat every 2–4 hours if needed.
LoE:IVbiv
OR
- Salbutamol, inhalation using a MDI,
- Salbutamol 400–1000 mcg (4–10 puffs), up to 20 puffs, using a spacer.
LoE:IVbv - Inhale 1 puff at a time. Allow for 6 breaths through the spacer between puffs.
- If no relief, repeat every 20–30 minutes until PEF > 60% of predicted.
- Once PEF > 60% of predicted, repeat every 2–4 hours if needed.
- Salbutamol 400–1000 mcg (4–10 puffs), up to 20 puffs, using a spacer.
Note
Administering salbutamol via a spacer is as effective as, and cheaper than, using a nebuliser.
LoE:IVbvi
If response is poor after first salbutamol nebulisation/inhalation:
ADD
- Ipratropium bromide 0.5 mg/2ml; nebuliser solution.
LoE:IIbvii - Ipratropium bromide, 2 mL (0.5 mg) added to salbutamol 1 mL (5 mg) solution and made up to 4 mL with sodium chloride 0.9%.
- Administer every 20–30 minutes for 3 doses depending on clinical response.
OR
- Ipratropium bromide, MDI, 80–160 mcg (2–4 puffs), using a spacer every 20-30 minutes as needed for up to 3 hours.
LoE:IIbviii
AND
- Corticosteroids (intermediate-acting) e.g.:
LoE:IVbix - Prednisone, oral, 40 mg immediately.
- Follow with prednisone, oral, 40 mg daily for 7 days.
OR
In patients who cannot use oral therapy, are vomiting, or are suspected to have gastric atony from a severe asthma exacerbation:
LoE:IVbx
- Hydrocortisone IM/slow IV, 100 mg 6 hourly.
Once oral medication can be taken, switch to:
- Corticosteroids (intermediate-acting) e.g.:
- Prednisone, oral, 40 mg daily for 7 days.
CAUTION
Avoid sedation of any kind.
Note:
If poor response to treatment, consider alternate diagnosis and refer urgently.
Life- threatening attacks
- Oxygen, to keep oxygen saturation 93-95%.
AND
- Salbutamol 0.5% (5 mg/mL) with ipratropium bromide 0.5 mg/2mL nebuliser solution:
- Salbutamol 0.5%, 2 mL (10 mg) plus ipratropium bromide, 2 mL (0.5 mg) every 20–30 minutes depending on clinical response for 4 doses over 2 hours.
- Delivered at a flow rate of 8 L/min with oxygen.
- If no relief, repeat every 20–30 minutes until asthma severity category moves from life-threatening to severe.
AND
- Parenteral corticosteroids (intermediate-acting), e.g.:
- Hydrocortisone IM/slow IV, 100 mg 6 hourly.
LoE:IVbxi
Once oral medication can be taken, switch to:
- Corticosteroids (intermediate-acting) e.g.:
- Prednisone, oral, 40 mg daily for 7 days.
CAUTION
Avoid sedation of any kind.
Note:
As clinical condition responds to treatment and severity improves to becomes severe but not life threatening, treat as per severe asthma exacerbation above.
Assessment of response in adults
| Response | No response | |
| PEFR (if possible) | improvement by >20% | improvement by <20% |
| Respiratory rate | <20 breaths/ minute | >20 breaths/ minute |
| Speech | normal | impaired |
Monitor response with PEF and clinical signs. Patients who fail to respond within 1 hour (symptomatic improvement and PEF >60% of predicted/personal best):
- Exclude upper airway obstruction/stridor, pneumothorax, and anaphylaxis.
- Discuss management with a specialist.
- Intubation and ventilator support may be required.
- If referral to another facility is required, the patient needs to be stabilised prior to transfer and transported by the appropriate level of transport discuss with the referral centre.
In patients with a poor response:
ADD
- Magnesium sulphate, IV, (50 mg/kg, maximum dose 2 g) in 100 mL sodium chloride 0.9%, as a single dose, administered over 20 minutes.
- Intravenous magnesium, single dose, has been shown to reduce the rate of hospitalisation.
LoE: Ixii
There is good evidence to recommend against the use of intravenous aminophylline in acute asthma as its use, together with high-dose nebulised ß2-agonists, does not result in significant additional bronchodilation, and leads to a significant increase in toxicity (vomiting and dysrhythmias).
LoE: Ixiii
Intercurrent bacterial respiratory infections
Bacterial infections are seldom present in acute exacerbations of asthma and yellow sputum production is usually related to presence of eosinophils. Antibiotics do not play a role in the management of asthma unless there is air space consolidation on CXR. See Section 16.6: Pneumonia, community acquired.
Standard Treatment Guidelines and Essential Medicines List for South Africa, Adult Hospital Level, 2020-2024_Version 1.1_16 September 2024
Chapter 16: Respiratory Disorders _16.1 Asthma, Acute