The aim of this chapter is to explore the subject of Critical Care Outreach services and the use of physiological track and trigger systems to detect developing critical illness. Outreach is part of an innovative approach to critical care, which is based

on a patient’s needs, rather than their location in the hospital. In recent years Critical Care Outreach services have become a popular choice for NHS Acute hospitals in helping manage acutely ill patients outside the traditional boundaries of intensive care units (ICU).