Management of acute asthma in adults in general practice

This content is from the BTS/SIGN British guideline on the management of asthma (SIGN 158), 2019.

Preventing poor outcomes

Many deaths from asthma are preventable. Delay can be fatal. Factors leading to poor outcome include:

Clinical staff failing to assess severity by objective measurement
Patients or relatives failing to appreciate severity
Under use of corticosteroids.

Regard each emergency asthma consultation as for acute severe asthma until shown otherwise.

Assess and record:

Peak expiratory flow (PEF)
Symptoms and response to self treatment
Heart and respiratory rates
Oxygen saturation (by pulse oximetry).

Caution: Patients with severe or life-threatening attacks may not be distressed and may not have all the abnormalities listed below. The presence of any should alert the doctor.

Moderate asthma

Initial assessment

PEF>50–75% best or predicted.

Further assessment

SpO₂ ≥92%
Speech normal
Respiration <25 breaths/min
Pulse <110 beats/min.

Management

Treat at home or in surgery and assess response to treatment.

Treatment

β₂ bronchodilator:
- via spacer*
- If no improvement:
  - via nebuliser (preferably oxygen-driven), salbutamol 5 mg
Give prednisolone 40–50 mg
Continue or increase usual treatment.

If good response to first treatment (symptoms improved, respiration and pulse settling and PEF >50%) continue or increase usual treatment and continue prednisolone.

Admit to hospital if any:

Life-threatening features
Features of acute severe asthma present after initial treatment
Previous near-fatal asthma.

Lower threshold for admission if afternoon or evening attack, recent nocturnal symptoms or hospital admission, previous severe attacks, patient unable to assess own condition, or concern over social circumstances.

* β₂ bronchodilator via spacer given one puff at a time, inhaled separately using tidal breathing; according to response, give another puff every 60 seconds up to a maximum of 10 puffs

Acute severe asthma

Initial assessment

PEF 33–50% best or predicted.

Further assessment

SpO₂ ≥92%
Can’t complete sentences
Respiration ≥25 breaths/min
Pulse ≥110 beats/min.

Management

Consider admission

Treatment

Oxygen to maintain SpO₂ 94–98% if available
β₂ bronchodilator:
- via nebuliser (preferably oxygen-driven), salbutamol 5 mg
- or if nebuliser not available, via spacer*
Prednisolone 40–50 mg or IV hydrocortisone 100 mg
If no response in acute severe asthma: admit.

* β₂ bronchodilator via spacer given one puff at a time, inhaled separately using tidal breathing; according to response, give another puff every 60 seconds up to a maximum of 10 puffs

Life-threatening asthma

Initial assessment

PEF<33% best or predicted

Further assessment

SpO₂ <92%
Silent chest, cyanosis or poor respiratory effort
Arrhythmia or hypotension
Exhaustion, altered consciousness.

Management

Arrange immediate admission.

Treatment

Oxygen to maintain SpO₂ 94–98%
β₂ bronchodilator with ipratropium:
- via nebuliser (preferably oxygen-driven), salbutamol 5 mg and ipratropium 0.5mg
- or if nebuliser and ipratropium not available, β₂ bronchodilator via spacer*
- Prednisolone 40–50 mg or IV hydrocortisone 100 mg immediately.

Admit to hospital.

* β₂ bronchodilator via spacer given one puff at a time, inhaled separately using tidal breathing; according to response, give another puff every 60 seconds up to a maximum of 10 puffs

If admitting the patient to hospital

Stay with patient until ambulance arrives
Send written assessment and referral details to hospital
β₂ bronchodilator via oxygen-driven nebuliser in ambulance.

Follow up after treatment or discharge from hospital

Continue prednisolone until recovery (minimum 5 days)
GP review within 2 working days
Monitor symptoms and PEF
Check inhaler technique
Written asthma action plan
Modify treatment according to guidelines for chronic persistent asthma
Address potentially preventable contributors to admission.