Respiratory viruses in the intensive care unit

Respiratory viruses cause a number of clinical 'syndromes' in the intensive care unit with different viruses being able to produce similar clinical pictures. Our main presenting problems are upper airway (e.g. croup and tracheitis), lower airway with intrapulmonary shunt (e.g. bronchitis and pneumonia), lower airway with dynamic hyperinflation (e.g. bronchiolitis and wheeze) and control of breathing (e.g. apnoea). This pragmatic classification is used because it enables focus on the physiological abnormality needing treatment, and how best to deliver appropriate and adequate ventilator support. This review provides an overview of these syndromes and a more detailed account of respiratory syncytial virus, our most commonly diagnosed winter illness.