The biological cost of the depression of consciousness

Abstract

The care of the brain and protection of cognitive function are critical aspects of our management of patients that are admitted to the intensive care unit or undergo general anesthesia and surgery. The depth of consciousness is frequently altered in an effort to make the patient comfortable during an unpleasant episode or procedure. This alteration in consciousness is often not controlled and patients maybe taken to very deep levels of unconsciousness or even coma and when returned to the conscious state are found to have acute brain dysfunction as exhibited by delirium and cognitive impairment. This may be compounded by the effects of sepsis and the inflammation of surgery and trauma causing endothelial dysfunction in the cerebral microcirculation. To prevent these deleterious effects on cognition, some of which maybe permanent, lighter controlled sedation with good analgesia is now being recommended in the intensive care unit. The concept of the “animated ICU“ is being put forward, where the patient maintains cognitive function and is mobilized when feasible. When deeper levels of sedation or anesthesia are required brain function monitors that display the electroencephalogram pattern may control the depth of unconsciousness. Innovative new therapies are being investigated to protect the brain from inflammation and the developing brain from potentially neurotoxic anesthetic agents. The cognitive mind is the most vital asset that we have and must be closely protected from impairment. Anestezjologia i Ratownictwo 2013; 7: 312-317.