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Semin Respir Crit Care Med 2006; 27(3): 210-220
DOI: 10.1055/s-2006-945532
Copyright © 2006 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA.

Delirium and Cognitive Dysfunction in the Intensive Care Unit

Russell R. Miller1  III , E. Wesley Ely1 , 2 , 3
  • 1Division of Allergy, Pulmonary, and Critical Care Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee
  • 2Department of Medicine, Center for Health Services Research, Nashville, Tennessee
  • 3Veterans Affairs Tennessee Valley Geriatric Research, Education, and Clinical Center (GRECC), Nashville, Tennessee
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Publication History

Publication Date:
21 June 2006 (online)

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ABSTRACT

Delirium remains an underrecognized, but highly prevalent, form of organ dysfunction in the intensive care unit (ICU). Intensivists have begun to benefit from elucidation of risk factors for delirium in the ICU, some of which are modifiable, whereas others are not. In the last 5 years, a new tool for use in detecting delirium among critically ill patients has been adapted, validated, and found objectively reliable for use at the bedside by nonpsychiatrists. Moreover, that tool-the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU)-has enabled determination of the serious sequelae of delirium, including increased mortality, higher cost, longer length of hospital stay, failure of extubation, and burdensome long-term cognitive impairment. Although prevention and treatment options exist, little data guide current pharmacological approaches to delirium, and nonpharmacological approaches have yet to be fully adopted by ICUs. Ongoing trials will address some of these limitations, but large cohort studies within the ICU are needed to further clarify risk factors and to identify targets to modify the occurrence and course of delirium. Furthermore, consideration of a continuum may better elucidate the true magnitude of acute brain dysfunction in the ICU.

KEYWORDS

Delirium - aged - lorazepam - cognitive impairment - mechanical ventilation - sedatives - analgesics - critical care

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Russell R Miller IIIM.D. M.P.H. 

Division of Allergy, Pulmonary, and Critical Care Medicine, Center for Health Services Research

6th Fl. Medical Center East 6100, Vanderbilt University Medical Center, Nashville, TN 37232-8300

Email: russell.miller@vanderbilt.edu

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