Significant improvements have been made with regard to mortality in patients with sepsis and critical illness over the last decade. However, this success is mitigated by the fact that 60-80 % of critically ill patients will become delirious during their hospital stay1, 50-70% will suffer cognitive impairment after discharge,2 and 60-80% will have physical disability due to ICU acquired weakness3. Furthermore, survivors of critical illness are five times more likely to develop depression4 after discharge and up to 25% will experience symptoms of post-traumatic stress disorder (PTSD)5.

Immobility in the intensive care unit (ICU) is associated with neuromuscular weakness, post–intensive care syndrome, functional limitations, and high costs. Early mobility–based rehabilitation in the ICU is feasible and safe. Mobility-based rehabilitation varied widely across 5 ICUs in 1 health care system, suggesting a need for continuous training and evaluation to maintain a strong mobility-based rehabilitation program. Early mobility–based rehabilitation shortens ICU and hospital stays, reduces delirium, and increases muscle strength and the ability to ambulate. Long-term effects include increased ability for self-care, faster return to independent functioning, improved physical function, and reduced hospital readmission and death. Factors that influence early mobility–based rehabilitation include having an interdisciplinary team; strong unit leadership; access to physical, occupational, and respiratory therapists; a culture focused on patient safety and quality improvement; a champion of early mobility; and a focus on measuring performance and outcomes.

The aim in this literature review is to describe the definitions, denominations, clinical signs and symptoms, explanations, causative factors and interrelationships of the intensive care syndrome discussed since 1950. It was found that there is no agreement about which symptoms should be included in the syndrome, when the syndrome may appear and how many patients may be affected. Furthermore, it is unclear what causes the development of the syndrome; most authors conclude that there are many reasons for it. The syndrome has generally been examined by using a medical or psychological approach, but during the last few years it has also been described and analysed from a nursing care perspective.