Management of severe viral bronchiolitis and severe acute asthma.

Severe viral bronchiolitis and severe acute asthma are common causes of acute respiratory insufficiency in infants and children beyond the neonatal period. Both are associated with considerable morbidity and can be fatal if management is inadequate. However, it is possible to reduce mortality to a minimum with appropriate therapy. The term 'status asthmaticus' is not used in this review because of uncertainty about precise definition. By 'severe acute asthma' is meant an acute episode of respiratory distress and wheezing not responding to conventional oral and/or inhalational bronchodilator therapy and which if continued unchecked would become lifethreatening. The approach to management outlined here has been used by the authors for the past 7 years. During each 12 months they see about 30 babies with severe acute bronchiolitis and about 40 children who between them have approximately 60 episodes of severe acute asthma. No patient with uncomplicated severe acute asthma under the authors' care has died in hospital during this period, though an 8-year-old child with very severe asthma who developed a tracheobronchitis caused by influenza A2 virus died in acute respiratory failure. Causes of death in the 4 fatal cases of viral bronchiolitis are outlined in Table I.