Neurologic Complications in Critically Ill Patients

Neurologic complications of sepsis are primarily mediated through inflammatory mediators that gain access to both the central and peripheral nervous systems. These mediators have significant effects on oxygen delivery and utilization at the level of the microvasculature endothelium and mitochondria. The resultant inhibition can lead to neurologic dysfunction and death through a variety of mechanisms including cellular, ischemia, hypoxia, and decreased axonal transport of nutrients. The encephalopathy associated with sepsis occurs in many critically ill patients. While a diagnosis of exclusion, its presence can be detected on examination and EEG monitoring, and portends worse outcome. Critical illness neuropathy and myopathy represent a spectrum of diseases that share in common the effects of inflammatory mediators and/or treatments initiated in the management of critically ill patients. The degree of neuromuscular dysfunction generally correlates with the duration and severity of the underlying illness. Both the central and peripheral manifestations of inflammatory mediators and related injury have a profound effect on long-term cognition and potential for rehabilitation.