Acute Asthmatic Attack (acute Exacerbation)

Clinical Description

Can be mild, moderate, severe or life threatening

Treatment Objective

• Relieve symptoms of bronchoconstriction with bronchodilators.
• Control airway inflammation with inhaled steroid (very important).
• Prevent further acute attacks and complications.
• Educate patients to avoid triggers where possible.
• Educate patient- good inhaler or spacer use technique and assess at every clinic visit.
• Monitor asthma treatment side effects and address appropriately.
• Assess and address patient fears/myths.
• Assess asthma control at each visit and adjust treatment accordingly

Assess adult patient

Signs of respiratory distress

RR, HR, O2 saturations, PEFR

Mild

Undistressed

RR < 25 / min, HR < 110 / min

O2 sats > 97%

PEFR > 75% predicted

Moderate distressed but no signs of severe asthma can complete a sentence

PEFR 50-75%

Severe distressed with signs of severe asthma cannot complete a sentence

RR > 25 / min, HR > 110 / min

SpO2 sats < 97%

PEFR 33-50%

Life-threatening exhausted, drowsy, confused silent chest, cyanotic

O2 sats < 92%

PEFR 33%

Treatment

5 mg salbutamol nebulizer or salbutamol 4 -10 puffs pMDI or spacer (repeat every 20 min) and reassess in 1h discharge if stable

Treatment

salbutamol 4 - 10 puffs pMDI or spacer (repeat every 20 min for 1 hr) or 5mg salbutamol nebulizer repeat after 15 -20 mins prednisolone 40 mg

PO od observe overnight

Treatment

5 mg salbutamol nebulizer every and repeat every 10 - 20 mins for 1hr then reassess oxygen supplement (aim 93-95%) prednisolone 40 mg

PO od magnesium sulphate 2 g slow IV (over 20 mins) stat (dose 40 mg /kg max 2 g) ± aminophylline IV (250 mg slow over 20 mins)

Treatment

5 mg salbutamol nebulizer and repeat every 10 - 20 mins for reassess oxygen supplement prednisolone 40 mg

PO od or IV hydrocortisone 200 mg 6 - 8 hrly magnesium sulphate 2 g slow IV +/- aminophylline IV

ICU review for elective intubation and mechanical ventilation

Discharge on prednisolone 40 mg PO od for 5 -7 days (prednisolone 1mg / kg max 50 mg od) salbutamol inhaler beclomethasone inhaler 2 puffs bd see in clinic in 4-6 weeks

Ongoing care regular medical review (involve seniors) if no improvement, needs ITU review consider pneumothorax, chest infection, other respiratory pathology ensure adequate hydration (including IV fluids)

Note: during asthmatic attack

• Can use plastic bottle as a spacer for inhalers
• Systemic steroids (oral prednisone or IV hydrocortisone) are VERY important:

exacerbation= inflammation. Give within 1hour of patient arrival to hospital as it takes about 4 hours for the steroids to start working

• Magnesium sulphate IV 1.2 -2 g stat (40 mg / kg, max 2 g) (dilute in saline and infusion over 20 minutes): mode of action: bronchodilator and anti-inflammatory.

Side effects: hypotension and respiratory depression (rare). Contra-indicated in severe renal failure (creatinine clearance < 30 ml / min), AV block, myocardial disease, myasthenia gravis.

• Give IV aminophylline slowly and watch for toxicity (arrhythmias and seizures).

Dosage: IV Aminophylline 250 IV slow push over 20minutes or 250 - 500mg as IV infusion in 1L of 5% Dextrose or 0.9% Sodium Chloride over 12 hours. Where possible IV aminophylline should be given when patient has not responded to salbutamol nebulization and magnesium sulphate

• If no response to above medication can give Adrenaline 0.5-1.0ml of 1:1000 slowly nebulized or IM
• When patient is already on maintenance oral Aminophylline avoid giving loading dose of IV Aminophylline
• Antibiotic only indicated if patient has signs of pneumonia
• Salbutamol tablets not ideal for asthmatic attack/asthma maintenance therapy (poor bioavailability and high risk of side effects e.g., heart palpitation/tremor).

Salbutamol inhaler preferred.

• If patient asthmatic attack not improving consider escalating treatment facility level, exclude pneumothorax, mimics of asthmatic attack (e.g., Pulmonary embolism, pulmonary edema)

MAINTENANCE AND PREVENTIVE TREATMENT OF ASTHMA - THE STEPWISE

APPROACH

• An environment free from cigarette and wood smoke can reduce attacks
• Check compliance and inhaler technique at
• each step before progressing
• Step up where required due to frequency of
• exacerbations
• Step down where possible:
• STEP 1: if symptoms less than twice a week Initial treatment should be with Salbutamol inhaled via a spacer device (see above) as required
• STEP 2: If symptoms more than twice a week add preventive therapy- inhaled steroid e.g. Beclomethasone 2 puffs (200mcg) 12 hourly via a spacer. Increasing to 4 puffs twice a day as required
• STEP 3: Refer for specialist care if no control with steps 1 & 2

Alternatively (to be used only if the above are NOT available)

• Give Aminophylline 100mg 12 hourly or 8 hourly.