Table 1

Proposed classification of critical illness11

Level 0Patients whose needs can be met through normal ward care in an acute hospital
Level 1Patients at risk of their condition deteriorating, or those recently relocated from higher levels of care, whose needs can be met on an acute ward with additional advice and support from the critical care team
Level 2Patients requiring more detailed observations or intervention including support for a single failing organ system or postoperative care and those “stepping down” from higher levels of care
Level 3Patients requiring advanced respiratory support alone or basic respiratory support together with support of at least two organ systems. This level includes all complex patients requiring support for multiorgan failure