ABSTRACT
Critical care is a service for patients with potentially recoverable conditions who can benefit from more detailed observation and invasive treatment than can safely be provided in general wards. Identification of the patients who are most likely to benefit from admission to a critical care unit can be very difficult. These resources are scarce and expensive. Patients who are not ill enough to require critical care and those unlikely to benefit because they are too ill must be excluded. In 1996, the United Kingdom Department of Health’s publication ‘Guidelines on admission to and discharge from Intensive Care and High Dependency Units’ provided useful advice. Since then, the concept of extending care to ill patients outside the walls of the critical care unit (Outreach Services) has led to a new classification of critically ill patients, which describes the level of care required (Level 0-4) instead of the location. A recent publication by the Intensive Care Society defines the criteria for these levels of care.
