Abstract
Severe brain injury is associated with a period of impaired level of consciousness
that can last from days to months and results in chronic impairment. Systematic assessment
of level of function in patients with disorders of consciousness (DoC) is critical
for diagnosis, prognostication, and evaluation of treatment efficacy. Approximately
40% of patients who are thought to be unconscious based on clinical bedside behavioral
assessment demonstrate some signs of consciousness on standardized behavioral assessment.
This finding, in addition to a growing body of literature demonstrating the advantages
of standardized behavioral assessment of DoC, has led multiple professional societies
and clinical guidelines to recommend standardized assessment over routine clinical
evaluation of consciousness. Nevertheless, even standardized assessment is susceptible
to biases and misdiagnosis, and examiners should consider factors, such as fluctuating
arousal and aphasia, that may confound evaluation. We review approaches to behavioral
assessment of consciousness, recent clinical guideline recommendations for use of
specific measures to evaluate patients with DoC, and strategies for mitigating common
biases that may confound the examination.
Keywords
brain injury - coma - consciousness - assessment
