Chronic Critical Illness: Current Aspects of the Problem (Review)

Chronic resuscitation patients who have survived the acute phase of a disease represent a fast-growing cohort of patients requiring specialized medical assistant in intensive care and resuscitation units (ICRU) for several months or years. The term "chronic critical illness" (CCI) was proposed for such patients in the mid-80s of the last century. Patients with CCI make up from 5 to 20% of ICRU. Over time, they develop homeostasis disorders resulting in multiple organ failure and death. Mortality in CCI exceeds that of the majority of malignant neoplasms and functional dependence remains in most of survivors. In the present review, the attempt is made to show the main links of CCI pathogenesis which, if acted upon, can prevent unfavorable outcome. The publications describing epidemiology of CCI, its outcomes, and clinical phenotype have been analyzed. Several researchers consider CCI as a result of persistent inflammation, immunosuppression, and catabolism syndrome. Some works show the importance of nutrition for ICRU patients. The role of gastrointestinal tract in CCI formation has been noted. The effect of intensive therapy on microbiota of the ICRU patients has been demonstrated. Microbiome disturbances in dysbiosis and sepsis have been considered, as well as the effect of intestinal microbiome on the distant organs. Post-intensive care syndrome is a significant constituent of CCI. The main sequelae of the syndrome, as well as the general questions of its prevention and treatment, have been denoted.