ICU · Respiratory / ventilation

Severe & Near-Fatal Asthma in the ICU

Also known as Severe asthma · Near-fatal asthma · Status asthmaticus · Acute severe asthma · Life-threatening asthma · Critical asthma syndrome · Magnesium sulphate in asthma · Ketamine for asthma · Permissive hypercapnia in asthma · Volatile anaesthetics in asthma · Heliox · VV-ECMO for asthma

Severe or near-fatal asthma (status asthmaticus) is graded by the British Thoracic Society as acute severe, life-threatening, or near-fatal. The escalation ladder is oxygen (SpO2 94-98 per cent), repeated or continuous nebulised salbutamol with ipratropium 0.5 mg, an early systemic corticosteroid (oral prednisolone, or intravenous hydrocortisone when the oral route is unsuitable), intravenous magnesium sulphate 2 g over 20 minutes for severe disease not responding to initial treatment, and second-line aminophylline or IV salbutamol. If the patient tires or the PaCO2 rises, intubate with a bronchodilating induction agent such as ketamine and ventilate for permissive hypercapnia (low tidal volume, low rate, long expiration, plateau pressure kept below about 30 cmH2O). Refractory bronchospasm is treated with inhalational volatile anaesthetics (sevoflurane), Heliox, or VV-ECMO. Watch for the auto-PEEP arrest, tension pneumothorax, lactic acidosis, and hypokalaemia.