Challenge in modern intensive care: chronic critical illness-pathophysiology and therapeutic options

The recent developments in intensive care have resulted in improved survival rates of patients treated with acute or-gan deficiency. As a consequence, the rate of those who survive the acute phase and subsequently require protracted organ support due to persisting organ dysfunction has been growing. Several survivors display chronic health status deterioration leading to prolonged rehabilitation or nursing, and repeated hospitalizations. The condition developed following the survival of the acute phase and requiring long-lasting intensive care is frequently termed as chronic critical illness (CCI). Several definitions exist, most of these are based on the number of ventilator days, or days of stay at the intensive care unit. Nevertheless, in spite of the initially heterogenous etiology of the acute illness, the complications associated with CCI, as well as the pathophysiological processes underlying these, are relatively uniform. This causes CCI to be a unique clinical syndrome characterized by the development of secondary infections, myopathy, central and peripheral neuropathy, and typical alterations of the hormonal and immune system functions. The outcome is heavily influenced by the frailty and comorbidities of the patient, in addition to the severity of the acute illness. The treatment of CCI patients presents a complicated task requiring multidisciplinary view and indi-vidualized therapeutic measures. Since the aging of the population and the continuously improving success rates in overcoming acute conditions also facilitate the development of CCI, the systematic overview of the underlying pathophysiological processes is pivotal for the optimization of the medical, nursing, social and economical burden presented by this syndrome.