Comorbidity Development in Patients with Severe Brain Injury Resulting in Chronic Critical Condition (Review)

Advances in intensive care have enabled patients to survive an acute critical condition, producing a growing population of patients in a chronic critical condition with long-term dependence on intensive care. These patients make up 5–10% of all patients with acute respiratory failure and require a disproportionate share of resources in the intensive care units, with an overall yearly survival rate of 40–50%.
The aim of review is to identify the impact of comorbid complications on the course and outcome of patients with severe brain injury.
Ninety-six sources were selected according to the data characterizing the clinical (syndromic) model of the patient with consciousness disorders after coma of different etiologies. This model takes into account the stages and phases of the syndrome as well as a number of comorbid conditions that determine the course and outcome of the disease.
The list of sources includes papers addressing the issues of comorbidity in patients with brain injury and conditions such as strokes, consequences of severe brain injury and brain surgery.
The sources reflecting the most significant mechanisms of consistent development of comorbidities were examined. These include metabolic disorders with subsequent protein and energy deficiency and comorbidities of the gastrointestinal tract. The role of microbiome in the development of comorbidity in patients in chronic critical condition was also identified.
Conclusion. The comorbidity development starts from the moment of brain injury and extends until sustained stabilization or multi-organ failure and death. Timely detection and correction of comorbidities allows optimizing treatment and increasing efficiency of rehabilitation in patients with severe brain injury.

comorbidity, chronic critical condition, hypermetabolism, hypercatabolism, microbiome

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