Potential mechanisms and markers of critical illness-associated cognitive dysfunction.
OBJECTIVE
To review the current understanding of the potential mechanisms of critical illness-associated cognitive dysfunction and to provide insight into markers that could be used to evaluate the influence of specific mechanisms in individual patients.


RESULTS
Cognitive dysfunction is common in critically ill patients, not only during the acute illness but also long after its resolution. Several pathophysiologic mechanisms are thought to underlie critical illness-associated cognitive dysfunction, including neurotransmitter abnormalities and occult diffuse brain injury. Markers that could be used to evaluate the influence of specific mechanisms in individual patients include serum anticholinergic activity, certain brain proteins, and tissue sodium concentration determination by way of high-resolution three-dimensional magnetic resonance imaging.


CONCLUSIONS
Although recent advances in this area are exciting, they are still too immature to influence patient care. Additional research is needed to provide a better understanding of the relative contribution of specific mechanisms to the development of critical illness-associated cognitive dysfunction and to determine whether these mechanisms might be amenable to treatment or prevention.
Milbrandt
Eric B
EB
The CRISMA Laboratory (Clinical Research, Investigation, and Systems Modeling of Acute Illness), Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA. milbeb@ccm.upmc.edu
Angus
Derek C
DC
D015415:Biomarkers / Q000378:metabolism; D001930:Brain Injuries / Q000175:diagnosis / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology; D003072:Cognition Disorders / Q000175:diagnosis* / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology; D003422:Critical Care / Q000379:methods; D016638:Critical Illness / Q000628:therapy*; D006801:Humans; D018377:Neurotransmitter Agents / Q000378:metabolism
D015415:Biomarkers; D018377:Neurotransmitter Agents